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Practice Guidelines for Obstetric Anesthesia
An Updated Report by the American Society of Anesthesiologists Task Force onObstetric Anesthesia* PRACTICE guidelines are systematically developed rec- tivities performed during labor and vaginal delivery, ce- ommendations that assist the practitioner and patient in sarean delivery, removal of retained placenta, and making decisions about health care. These recommen- dations may be adopted, modified, or rejected accordingto clinical needs and constraints and are not intended to replace local institutional policies. In addition, practice The purposes of these Guidelines are to enhance the guidelines are not intended as standards or absolute quality of anesthetic care for obstetric patients, improve requirements, and their use cannot guarantee any spe- patient safety by reducing the incidence and severity of cific outcome. Practice guidelines are subject to revision anesthesia-related complications, and increase patient as warranted by the evolution of medical knowledge, technology, and practice. They provide basic recommen-dations that are supported by a synthesis and analysis of the current literature, expert opinion, open forum com- These Guidelines focus on the anesthetic management mentary, and clinical feasibility data.
of pregnant patients during labor, nonoperative delivery, This update includes data published since the “Prac- operative delivery, and selected aspects of postpartum tice Guidelines for Obstetrical Anesthesia” were adopted care and analgesia (i.e., neuraxial opioids for postpartum by the American Society of Anesthesiologists in 1998; it analgesia after neuraxial anesthesia for cesarean deliv- also includes data and recommendations for a wider ery). The intended patient population includes, but is range of techniques than was previously addressed.
not limited to, intrapartum and postpartum patients withuncomplicated pregnancies or with common obstetricproblems. The Guidelines do not apply to patients un- Methodology
dergoing surgery during pregnancy, gynecologic pa- A. Definition of Perioperative Obstetric Anesthesia tients, or parturients with chronic medical disease (e.g., For the purposes of these Guidelines, obstetric anes- severe cardiac, renal, or neurologic disease). In addition, thesia refers to peripartum anesthetic and analgesic ac- these Guidelines do not address (1) postpartum analge-sia for vaginal delivery, (2) analgesia after tubal ligation,or (3) postoperative analgesia after general anesthesia This article is featured in “This Month in Anesthesiology.” Please see this issue of ANESTHESIOLOGY, page 5A.
Additional material related to this article can be found on theANESTHESIOLOGY Web site. Go to http://www.anesthesiology.
These Guidelines are intended for use by anesthesiol- org, click on Enhancements Index, and then scroll down to ogists. They also may serve as a resource for other find the appropriate article and link. Supplementary material anesthesia providers and healthcare professionals who can also be accessed on the Web by clicking on the “Arti- advise or care for patients who will receive anesthetic clePlus” link either in the Table of Contents or at the top of care during labor, delivery, and the immediate postpar- * Developed by the American Society of Anesthesiologists Task Force on E. Task Force Members and Consultants Obstetric Anesthesia: Joy L. Hawkins, M.D. (Chair), Denver, Colorado; James F.
The American Society of Anesthesiologists (ASA) ap- Arens, M.D., Houston, Texas; Brenda A Bucklin, M.D., Denver, Colorado; RichardT. Connis, Ph.D., Woodinville, Washington; Patricia A. Dailey, M.D., Hillsbor- pointed a Task Force of 11 members to (1) review the ough, California; David R. Gambling, M.B.B.S., San Diego, California; David G.
published evidence, (2) obtain the opinion of a panel of Nickinovich, Ph.D., Bellevue, Washington; Linda S. Polley, M.D., Ann Arbor,Michigan; Lawrence C. Tsen, M.D., Boston, Massachusetts; David J. Wlody, M.D., consultants including anesthesiologists and nonanesthe- Brooklyn, New York; and Kathryn J. Zuspan, M.D., Stillwater, Minnesota.
siologist physicians concerned with obstetric anesthesia Submitted for publication October 31, 2006. Accepted for publication Octo- and analgesia, and (3) obtain opinions from practitioners ber 31, 2006. Supported by the American Society of Anesthesiologists under thedirection of James F. Arens, M.D., Chair, Committee on Standards and Practice likely to be affected by the Guidelines. The Task Force Parameters. Approved by the House of Delegates on October 18, 2006. A list of included anesthesiologists in both private and academic the references used to develop these Guidelines is available by writing to theAmerican Society of Anesthesiologists.
practices from various geographic areas of the United Address reprint requests to the American Society of Anesthesiologists: 520 States and two consulting methodologists from the ASA North Northwest Highway, Park Ridge, Illinois 60068-2573. This Practice Guide- Committee on Standards and Practice Parameters.
line, as well as all published ASA Practice Parameters, may be obtained at no costthrough the Journal Web site, www.anesthesiology.org.
The Task Force developed the Guidelines by means of a seven-step process. First, they reached consensus on vestigate a relationship between an intervention and the criteria for evidence. Second, original published re- search studies from peer-reviewed journals relevant to Inadequate: The available studies cannot be used to obstetric anesthesia were reviewed. Third, the panel of assess the relationship between an intervention and an expert consultants was asked to (1) participate in opin- outcome. These studies either do not meet the criteria ion surveys on the effectiveness of various peripartum for content as defined in the Focus section of these management strategies and (2) review and comment on Guidelines, or do not permit a clear causal interpreta- a draft of the Guidelines developed by the Task Force.
tion of findings due to methodologic concerns.
Fourth, opinions about the Guideline recommendations Formal survey information is collected from consult- were solicited from active members of the ASA who ants and members of the ASA. The following terms provide obstetric anesthesia. Fifth, the Task Force held describe survey responses for any specified issue. Re- open forums at two major national meetings† to solicit sponses are solicited on a five-point scale ranging from 1 input on its draft recommendations. Sixth, the consult- (strongly disagree) to 5 (strongly agree), with a score of ants were surveyed to assess their opinions on the fea- 3 being equivocal. Survey responses are summarized sibility of implementing the Guidelines. Seventh, all available information was used to build consensuswithin the Task Force to finalize the Guidelines (appen- Strongly Agree: Median score of 5 (at least 50% of the Agree: Median score of 4 (at least 50% of the responses F. Availability and Strength of Evidence Preparation of these Guidelines followed a rigorous Equivocal: Median score of 3 (at least 50% of the re- methodologic process (appendix 2). To convey the find- sponses are 3, or no other response category or com- ings in a concise and easy-to-understand fashion, these bination of similar categories contain at least 50% of Guidelines use several descriptive terms. When suffi- cient numbers of studies are available for evaluation, the Disagree: Median score of 2 (at least 50% of the re- following terms describe the strength of the findings.
Strongly Disagree: Median score of 1 (at least 50% of the Support: Meta-analysis of a sufficient number of random- ized controlled trials‡ indicates a statistically signifi-cant relationship (P Ͻ 0.01) between a clinical inter- Guidelines
Suggest: Information from case reports and observational studies permits inference of a relationship between an History and Physical Examination. Although com-
intervention and an outcome. A meta-analytic assess- parative studies are insufficient to evaluate the peripar- ment of this type of qualitative or descriptive informa- tum impact of conducting a focused history (e.g., review- ing medical records) or a physical examination, the Equivocal: Either a meta-analysis has not found signifi- literature reports certain patient or clinical characteris- cant differences among groups or conditions, or there tics that may be associated with obstetric complications.
is insufficient quantitative information to conduct a These characteristics include, but are not limited to, meta-analysis and information collected from case re- preeclampsia, pregnancy-related hypertensive disorders, ports and observational studies does not permit infer- HELLP syndrome, obesity, and diabetes.
ence of a relationship between an intervention and an The consultants and ASA members both strongly agree that a directed history and physical examination, as wellas communication between anesthetic and obstetric pro- The lack of scientific evidence in the literature is viders, reduces maternal, fetal, and neonatal complica- Silent: No identified studies address the specified rela- Recommendations. The anesthesiologist should con- tionship between an intervention and outcome.
duct a focused history and physical examination be- Insufficient: There are too few published studies to in- fore providing anesthesia care. This should include,but is not limited to, a maternal health and anesthetichistory, a relevant obstetric history, a baseline blood † International Anesthesia Research Society, 80th Clinical and Scientific Con- gress, San Francisco, California, March 25, 2006; and Society of Obstetric Anes- pressure measurement, and an airway, heart, and lung thesia and Perinatology 38th Annual Meeting, Hollywood, Florida, April 29, 2006.
examination, consistent with the ASA “Practice Advi- ‡ A prospective nonrandomized controlled trial may be included in a meta- sory for Preanesthesia Evaluation.”§ When a neuraxial analysis under certain circumstances if specific statistical criteria are met.
anesthetic is planned or placed, the patient’s back § American Society of Anesthesiologists Task Force on Preanesthesia Evaluation: Practice advisory for preanesthesia evaluation. ANESTHESIOLOGY 2002; 96:485–96.
Recognition of significant anesthetic or obstetric risk bers agree, however, that perianesthetic recording of the factors should encourage consultation between the ob- fetal heart rate reduces fetal and neonatal complications.
stetrician and the anesthesiologist. A communication Recommendations. The fetal heart rate should be system should be in place to encourage early and ongo- monitored by a qualified individual before and after ad- ing contact between obstetric providers, anesthesiolo- ministration of neuraxial analgesia for labor. The Task gists, and other members of the multidisciplinary team.
Force recognizes that continuous electronic recording Intrapartum Platelet Count. The literature is insuf-
of the fetal heart rate may not be necessary in every ficient to assess whether a routine platelet count can clinical setting and may not be possible during initiation predict anesthesia-related complications in uncompli- cated parturients. The literature suggests that a plateletcount is clinically useful for parturients with suspected pregnancy-related hypertensive disorders, such as pre- Clear Liquids. There is insufficient published evi-
eclampsia or HELLP syndrome, and for other disorders dence to draw conclusions about the relationship be- tween fasting times for clear liquids and the risk of The ASA members are equivocal, but the consultants emesis/reflux or pulmonary aspiration during labor. The agree that obtaining a routine intrapartum platelet count consultants and ASA members both agree that oral intake does not reduce maternal anesthetic complications.
of clear liquids during labor improves maternal comfort Both the consultants and ASA members agree that, for and satisfaction. Although the ASA members are equiv- patients with suspected preeclampsia, a platelet count ocal, the consultants agree that oral intake of clear liq- reduces maternal anesthetic complications. The consult- uids during labor does not increase maternal complica- ants strongly agree and the ASA members agree that a platelet count reduces maternal anesthetic complica- tions for patients with suspected coagulopathy.
amounts of clear liquids may be allowed for uncompli- Recommendations. A specific platelet count predic- cated laboring patients. The uncomplicated patient un- tive of neuraxial anesthetic complications has not been dergoing elective cesarean delivery may have modest determined. The anesthesiologist’s decision to order or amounts of clear liquids up to 2 h before induction of require a platelet count should be individualized and anesthesia. Examples of clear liquids include, but are not based on a patient’s history, physical examination, and limited to, water, fruit juices without pulp, carbonated clinical signs. A routine platelet count is not necessary in beverages, clear tea, black coffee, and sports drinks.࿣ The volume of liquid ingested is less important than the Blood Type and Screen. The literature is insufficient
presence of particulate matter in the liquid ingested.
to determine whether obtaining a blood type and screen However, patients with additional risk factors for aspira- is associated with fewer maternal anesthetic complica- tion (e.g., morbid obesity, diabetes, difficult airway) or tions. In addition, the literature is insufficient to deter- patients at increased risk for operative delivery (e.g., mine whether a blood cross-match is necessary for nonreassuring fetal heart rate pattern) may have further healthy and uncomplicated parturients. The consultants restrictions of oral intake, determined on a case-by-case and ASA members agree that an intrapartum blood sam- ple should be sent to the blood bank for all parturients.
Solids. A specific fasting time for solids that is predic-
Recommendations. A routine blood cross-match is not tive of maternal anesthetic complications has not been necessary for healthy and uncomplicated parturients for determined. There is insufficient published evidence to vaginal or operative delivery. The decision whether to address the safety of any particular fasting period forsolids in obstetric patients. The consultants and ASA order or require a blood type and screen, or cross-match, members both agree that the oral intake of solids during should be based on maternal history, anticipated hemor- labor increases maternal complications. They both rhagic complications (e.g., placenta accreta in a patient strongly agree that patients undergoing either elective with placenta previa and previous uterine surgery), and cesarean delivery or postpartum tubal ligation should undergo a fasting period of 6 – 8 h depending on the type Perianesthetic Recording of the Fetal Heart Rate.
of food ingested (e.g., fat content).࿣ The Task Force The literature suggests that anesthetic and analgesic recognizes that in laboring patients the timing of deliv- agents may influence the fetal heart rate pattern. There is ery is uncertain; therefore, compliance with a predeter- insufficient literature to demonstrate that perianesthetic mined fasting period before nonelective surgical proce- recording of the fetal heart rate prevents fetal or neona- tal complications. Both the consultants and ASA mem- Recommendations. Solid foods should be avoided in laboring patients. The patient undergoing elective sur- ࿣ American Society of Anesthesiologists Task Force on Preoperative Fasting: gery (e.g., scheduled cesarean delivery or postpartum Practice guidelines for preoperative fasting and the use of pharmacologic agentsto reduce the risk of pulmonary aspiration. ANESTHESIOLOGY 1999; 90:896 –905.
tubal ligation) should undergo a fasting period for solids of 6 – 8 h depending on the type of food ingested (e.g., fat or anesthesia and maintained throughout the duration of the neuraxial analgesic or anesthetic. However, admin- Antacids, H Receptor Antagonists, and Metoclo-
istration of a fixed volume of intravenous fluid is not pramide. The literature does not sufficiently examine
required before neuraxial analgesia is initiated.
the relationship between reduced gastric acidity and the Timing of Neuraxial Analgesia and Outcome of
frequency of emesis, pulmonary aspiration, morbidity, or Labor. Meta-analysis of the literature determined that
mortality in obstetric patients who have aspirated gastric the timing of neuraxial analgesia does not affect the contents. Published evidence supports the efficacy of frequency of cesarean delivery. The literature also sug- preoperative nonparticulate antacids (e.g., sodium ci- gests that other delivery outcomes (i.e., spontaneous or trate, sodium bicarbonate) in decreasing gastric acidity instrumented) are also unaffected. The consultants during the peripartum period. However, the literature is strongly agree and the ASA members agree that early insufficient to examine the impact of nonparticulate initiation of epidural analgesia (i.e., at cervical dilations antacids on gastric volume. The literature suggests that of less than 5 cm vs. equal to or greater than 5 cm) H receptor antagonists are effective in decreasing gas- improves analgesia. They both disagree that motor block tric acidity in obstetric patients and supports the efficacy or maternal, fetal, or neonatal side effects are increased of metoclopramide in reducing peripartum nausea and vomiting. The consultants and ASA members agree that Recommendations. Patients in early labor (i.e., Ͻ 5 cm the administration of a nonparticulate antacid before dilation) should be given the option of neuraxial analge- operative procedures reduces maternal complications.
sia when this service is available. Neuraxial analgesia Recommendations. Before surgical procedures (i.e., should not be withheld on the basis of achieving an cesarean delivery, postpartum tubal ligation), practitio- arbitrary cervical dilation, and should be offered on an ners should consider the timely administration of non- individualized basis. Patients may be reassured that the use of neuraxial analgesia does not increase the inci- metoclopramide for aspiration prophylaxis.
Neuraxial Analgesia and Trial of Labor after Pre-
III. Anesthetic Care for Labor and Vaginal Delivery vious Cesarean Delivery. Nonrandomized compara-
Overview. Not all women require anesthetic care dur-
tive studies suggest that epidural analgesia may be used ing labor or delivery. For women who request pain relief in a trial of labor for previous cesarean delivery patients for labor and/or delivery, there are many effective anal- without adversely affecting the incidence of vaginal de- gesic techniques available. Maternal request represents livery. Randomized comparisons of epidural versus sufficient justification for pain relief. In addition, mater- other anesthetic techniques were not found. The con- nal medical and obstetric conditions may warrant the sultants and ASA members agree that neuraxial tech- provision of neuraxial techniques to improve maternal niques improve the likelihood of vaginal delivery for patients attempting vaginal birth after cesarean delivery.
The choice of analgesic technique depends on the medical status of the patient, progress of labor, and Recommendations. Neuraxial techniques should be resources at the facility. When sufficient resources (e.g., offered to patients attempting vaginal birth after previ- anesthesia and nursing staff) are available, neuraxial ous cesarean delivery. For these patients, it is also ap- catheter techniques should be one of the analgesic op- propriate to consider early placement of a neuraxial tions offered. The choice of a specific neuraxial block catheter that can be used later for labor analgesia, or for should be individualized and based on anesthetic risk anesthesia in the event of operative delivery.
factors, obstetric risk factors, patient preferences, Early Insertion of a Spinal or Epidural Catheter
progress of labor, and resources at the facility.
for Complicated Parturients. The literature is insuffi-
When neuraxial catheter techniques are used for anal- cient to assess whether, when caring for the compli- gesia during labor or vaginal delivery, the primary goal is cated parturient, the early insertion of a spinal or epi- to provide adequate maternal analgesia with minimal dural catheter, with later administration of analgesia, motor block (e.g., achieved with the administration of improves maternal or neonatal outcomes. The consult- local anesthetics at low concentrations with or without ants and ASA members agree that early insertion of a spinal or epidural catheter for complicated parturients When a neuraxial technique is chosen, appropriate resources for the treatment of complications (e.g., hypo- Recommendations. Early insertion of a spinal or epi- tension, systemic toxicity, high spinal anesthesia) should dural catheter for obstetric (e.g., twin gestation or pre- be available. If an opioid is added, treatments for related eclampsia) or anesthetic indications (e.g., anticipated complications (e.g., pruritus, nausea, respiratory depres- difficult airway or obesity) should be considered to re- sion) should be available. An intravenous infusion should duce the need for GA if an emergent procedure becomes be established before the initiation of neuraxial analgesia necessary. In these cases, the insertion of a spinal or epidural catheter may precede the onset of labor or a whether the addition of opioids increases maternal side patient’s request for labor analgesia.
Continuous Infusion Epidural Analgesia.
The literature is insufficient to determine whether in- CIE Compared with Parenteral Opioids. The literature duction of analgesia using local anesthetics with opioids suggests that the use of continuous infusion epidural compared with higher concentrations of epidural local (CIE) local anesthetics with or without opioids provides anesthetics without opioids provides improved quality greater quality of analgesia compared with parenteral or duration of analgesia. The consultants and ASA mem- (i.e., intravenous or intramuscular) opioids. The consult- bers are equivocal regarding improved analgesia, and ants and ASA members strongly agree that CIE local they both disagree that maternal, fetal, or neonatal side anesthetics with or without opioids provide improved effects are increased using lower concentrations of epi- analgesia compared with parenteral opioids.
dural local anesthetics with opioids.
Meta-analysis of the literature indicates that there is a For maintenance of analgesia, the literature suggests longer duration of labor, with an average duration of 24 that there are no differences in the analgesic efficacy of min for the second stage, and a lower frequency of low concentrations of epidural local anesthetics with spontaneous vaginal delivery when continuous epidural opioids compared with higher concentrations of epi- local anesthetics are administered compared with intra- dural local anesthetics without opioids. The Task Force venous opioids. Meta-analysis of the literature deter- notes that the addition of an opioid to a local anesthetic mined that there are no differences in the frequency of infusion allows an even lower concentration of local cesarean delivery. Neither the consultants nor ASA mem- anesthetic for providing equally effective analgesia.
bers agree that CIE local anesthetics compared with However, the literature is insufficient to examine parenteral opioids significantly (1) increase the duration whether a bupivacaine infusion concentration of less of labor, (2) decrease the chance of spontaneous deliv- than or equal to 0.125% with an opioid provides com- ery, (3) increase maternal side effects, or (4) increase parable or improved analgesia compared with a bupiva-caine concentration opioid.# Meta-analysis of the literature determined that CIE Compared with Single-injection Spinal. There is low concentrations of epidural local anesthetics with insufficient literature to assess the analgesic efficacy of opioids compared with higher concentrations of epi- CIE local anesthetics with or without opioids compared dural local anesthetics without opioids are associated to single-injection spinal opioids with or without local with reduced motor block. No differences in the dura- anesthetics. The consultants are equivocal, but the ASA tion of labor, mode of delivery, or neonatal outcomes are members agree that CIE local anesthetics improve anal- found when epidural local anesthetics with opioids are gesia compared with single-injection spinal opioids; both compared with epidural local anesthetics without opi- the consultants and ASA members are equivocal regard- oids. The literature is insufficient to determine the ef- ing the frequency of motor block. The consultants are fects of epidural local anesthetics with opioids on other equivocal, but the ASA members disagree that the use of maternal outcomes (e.g., hypotension, nausea, pruritus, CIE compared with single-injection spinal opioids in- respiratory depression, urinary retention).
creases the duration of labor. They both disagree that The consultants and ASA members both agree that CIE local anesthetics with or without opioids compared maintenance of epidural analgesia using low concentra- to single-injection spinal opioids with or without local tions of local anesthetics with opioids provides im- anesthetics decreases the likelihood of spontaneous de- proved analgesia compared with higher concentrations livery or increases maternal, fetal, or neonatal side ef- of local anesthetics without opioids. The consultants agree, but the ASA members are equivocal regarding the CIE with and without Opioids. The literature supports improved likelihood of spontaneous delivery when the induction of analgesia using epidural local anesthet- lower concentrations of local anesthetics with opioids ics combined with opioids compared with equal con- are used. The consultants strongly agree and the ASA centrations of epidural local anesthetics without opioids members agree that motor block is reduced. They agree for improved quality and longer duration of analgesia.
that maternal side effects are reduced with this drug The consultants strongly agree and the ASA members combination. They are both equivocal regarding a reduc- agree that the addition of opioids to epidural local anes- tion in fetal and neonatal side effects.
thetics improves analgesia; they both disagree that fetal Recommendations. The selected analgesic/anesthetic or neonatal side effects are increased. The consultants technique should reflect patient needs and preferences, disagree, but the ASA members are equivocal regarding practitioner preferences or skills, and available re-sources. The continuous epidural infusion technique # References to bupivacaine are included for illustrative purposes only, and may be used for effective analgesia for labor and deliv- because bupivacaine is the most extensively studied local anesthetic for contin- ery. When a continuous epidural infusion of local anes- uous infusion epidural analgesia. The Task Force recognizes that other localanesthetics are appropriate for continuous infusion epidural analgesia.
thetic is selected, an opioid may be added to reduce the concentration of local anesthetic, improve the quality of post– dural puncture headache. The consultants and ASA analgesia, and minimize motor block.
members both strongly agree that the use of pencil-point Adequate analgesia for uncomplicated labor and deliv- spinal needles reduces maternal complications.
ery should be administered with the secondary goal of Recommendations. Pencil-point spinal needles should producing as little motor block as possible by using be used instead of cutting-bevel spinal needles to mini- dilute concentrations of local anesthetics with opioids.
mize the risk of post– dural puncture headache.
The lowest concentration of local anesthetic infusion Combined Spinal–Epidural Analgesia. The litera-
that provides adequate maternal analgesia and satisfac- ture supports a faster onset time and equivalent analgesia tion should be administered. For example, an infusion with combined spinal– epidural (CSE) local anesthetics concentration greater than 0.125% bupivacaine is unnec- with opioids versus epidural local anesthetics with opioids.
essary for labor analgesia in most patients.
The literature is equivocal regarding the impact of CSE Single-injection Spinal Opioids with or without
versus epidural local anesthetics with opioids on maternal Local Anesthetics. The literature suggests that spinal
satisfaction with analgesia, mode of delivery, hypotension, opioids with or without local anesthetics provide effec- motor block, nausea, fetal heart rate changes, and Apgar tive analgesia during labor without altering the incidence scores. Meta-analysis of the literature indicates that the of neonatal complications. There is insufficient literature frequency of pruritus is increased with CSE.
to compare spinal opioids with parenteral opioids. There The consultants and ASA members both agree that CSE is also insufficient literature to compare single-injection local anesthetics with opioids provide improved early spinal opioids with local anesthetics versus single-injec- analgesia compared with epidural local anesthetics with tion spinal opioids without local anesthetics.
opioids. They are equivocal regarding the impact of CSE The consultants strongly agree and the ASA members with opioids on overall analgesic efficacy, duration of agree that spinal opioids provide improved analgesia labor, and motor block. The consultants and ASA mem- compared with parenteral opioids. They both disagree bers both disagree that CSE increases the risk of fetal or that, compared with parenteral opioids, spinal opioids neonatal side effects. The consultants disagree, but the increase the duration of labor, decrease the chance of ASA members are equivocal regarding whether CSE in- spontaneous delivery, or increase fetal and neonatal side creases the incidence of maternal side effects.
effects. The consultants are equivocal, but the ASA mem- Recommendations. Combined spinal– epidural tech- bers disagree that maternal side effects are increased niques may be used to provide effective and rapid onset Compared with spinal opioids without local anesthet- Patient-controlled Epidural Analgesia. The litera-
ics, the consultants and ASA members both agree that ture supports the efficacy of patient-controlled epidural spinal opioids with local anesthetics provide improved analgesia (PCEA) versus CIE in providing equivalent an- analgesia. They both disagree that the chance of sponta- algesia with reduced drug consumption. Meta-analysis of neous delivery is decreased and that fetal and neonatal the literature indicates that the duration of labor is side effects are increased. They are both equivocal re- longer with PCEA compared with CIE for the first stage garding an increase in maternal side effects. However, (e.g., an average of 36 min) but not the second stage of they both agree that motor block is increased when local labor. Meta-analysis of the literature also determined that anesthetics are added to spinal opioids. Finally, the con- mode of delivery, frequency of motor block, and Apgar sultants disagree, but the ASA members are equivocal scores are equivalent when PCEA administration is com- regarding an increase in the duration of labor.
pared with CIE. The literature supports greater analgesic efficacy for PCEA with a background infusion compared with or without local anesthetics may be used to provide with PCEA without a background infusion; meta-analysis effective, although time-limited, analgesia for labor when of the literature also indicates no differences in the mode spontaneous vaginal delivery is anticipated. If labor is of delivery or frequency of motor block. The consultants expected to last longer than the analgesic effects of the and ASA members agree that PCEA compared with CIE spinal drugs chosen or if there is a good possibility of improves analgesia and reduces the need for anesthetic operative delivery, a catheter technique instead of a interventions; they also agree that PCEA improves ma- single injection technique should be considered. A local ternal satisfaction. The consultants and ASA members are anesthetic may be added to a spinal opioid to increase equivocal regarding a reduction in motor block, an in- duration and improve quality of analgesia. The Task creased likelihood of spontaneous delivery, or a decrease Force notes that the rapid onset of analgesia provided by in maternal side effects with PCEA compared with CIE.
single-injection spinal techniques may be advantageous They both agree that PCEA with a background infusion for selected patients (e.g., those in advanced labor).
improves analgesia, improves maternal satisfaction, and Pencil-point Spinal Needles. The literature supports
reduces the need for anesthetic intervention. The ASA the use of pencil-point spinal needles compared with members are equivocal, but the consultants disagree that cutting-bevel spinal needles to reduce the frequency of a background infusion decreases the chance of sponta- neous delivery or increases maternal side effects. The available in the main operating suite. The consultants consultants and ASA members are equivocal regarding and ASA members strongly agree that the available the effect of a background infusion on the incidence of equipment, facilities, and support personnel should be Recommendations. Patient-controlled epidural analge- Recommendations. Equipment, facilities, and sup- sia may be used to provide an effective and flexible port personnel available in the labor and delivery approach for the maintenance of labor analgesia. The operating suite should be comparable to those avail- Task Force notes that the use of PCEA may be preferable able in the main operating suite. Resources for the to fixed-rate CIE for providing fewer anesthetic interven- treatment of potential complications (e.g., failed intu- tions and reduced dosages of local anesthetics. PCEA bation, inadequate analgesia, hypotension, respiratory may be used with or without a background infusion.
depression, pruritus, vomiting) should also be avail-able in the labor and delivery operating suite. Appro- priate equipment and personnel should be available to Anesthetic Techniques. The literature is insufficient
care for obstetric patients recovering from major to assess whether a particular type of anesthetic is more effective than another for removal of retained placenta.
General, Epidural, Spinal, or Combined Spinal–
The consultants strongly agree and the ASA members Epidural Anesthesia. The literature suggests that in-
agree that, if a functioning epidural catheter is in place duction-to-delivery times for GA are lower compared and the patient is hemodynamically stable, epidural an- with epidural or spinal anesthesia and that a higher esthesia is the preferred technique for the removal of frequency of maternal hypotension may be associated retained placenta. The consultants and ASA members with epidural or spinal techniques. Meta-analysis of the both agree that, in cases involving major maternal hem- literature found that Apgar scores at 1 and 5 min are orrhage, GA is preferred over neuraxial anesthesia.
lower for GA compared with epidural anesthesia and Recommendations. The Task Force notes that, in gen- suggests that Apgar scores are lower for GA versus spinal eral, there is no preferred anesthetic technique for re- anesthesia. The literature is equivocal regarding differ- moval of retained placenta. However, if an epidural cath- ences in umbilical artery pH values when GA is com- eter is in place and the patient is hemodynamically pared with epidural or spinal anesthesia.
stable, epidural anesthesia is preferable. Hemodynamic The consultants and ASA members agree that GA re- status should be assessed before administering neuraxial duces the time to skin incision when compared with anesthesia. Aspiration prophylaxis should be considered.
either epidural or spinal anesthesia; they also agree that Sedation/analgesia should be titrated carefully due to the GA increases maternal complications. The consultants potential risks of respiratory depression and pulmonary are equivocal and the ASA members agree that GA in- aspiration during the immediate postpartum period. In creases fetal and neonatal complications. The consult- cases involving major maternal hemorrhage, GA with an ants and ASA members both agree that epidural anesthe- endotracheal tube may be preferable to neuraxial anes- sia increases the time to skin incision and decreases the quality of anesthesia compared with spinal anesthesia.
Uterine Relaxation. The literature suggests that ni-
They both disagree that epidural anesthesia increases troglycerin is effective for uterine relaxation during the removal of retained placenta. The consultants and ASA When spinal anesthesia is compared with epidural members both agree that the administration of nitroglyc- anesthesia, meta-analysis of the literature found that in- erin for uterine relaxation improves success in removing duction-to-delivery times are shorter for spinal anesthe- sia. The literature is equivocal regarding hypotension, Recommendations. Nitroglycerin may be used as an umbilical pH values, and Apgar scores. The consultants alternative to terbutaline sulfate or general endotracheal and ASA members agree that epidural anesthesia in- anesthesia with halogenated agents for uterine relax- creases time to skin incision and reduces the quality of ation during removal of retained placental tissue. Initiat- anesthesia when compared with spinal anesthesia. They ing treatment with incremental doses of intravenous or both disagree that epidural anesthesia increases maternal sublingual (i.e., metered dose spray) nitroglycerin may relax the uterus sufficiently while minimizing potential When CSE is compared with epidural anesthesia, meta- complications (e.g., hypotension).
analysis of the literature found no differences in thefrequency of hypotension or in 1-min Apgar scores; the V. Anesthetic Choices for Cesarean Delivery literature is insufficient to evaluate outcomes associated Equipment, Facilities, and Support Personnel.
with the use of CSE compared with spinal anesthesia.
The literature is insufficient to evaluate the benefit of The consultants and ASA members agree that CSE anes- providing equipment, facilities and support personnel in thesia improves anesthesia and reduces time to skin the labor and delivery operating suite comparable to that incision when compared with epidural anesthesia. The ASA members are equivocal, but the consultants disagree tension during neuraxial anesthesia. In the absence of that maternal side effects are reduced. The consultants maternal bradycardia, phenylephrine may be preferable and ASA members both disagree that CSE improves an- because of improved fetal acid– base status in uncompli- esthesia compared with spinal anesthesia. The ASA members are equivocal, but the consultants disagree that Neuraxial Opioids for Postoperative Analgesia.
maternal side effects are reduced. The consultants For improved postoperative analgesia after cesarean de- strongly agree and the ASA members agree that CSE livery during epidural anesthesia, the literature supports compared with spinal anesthesia increases flexibility of the use of epidural opioids compared with intermittent prolonged procedures, and they both agree that the time injections of intravenous or intramuscular opioids. How- ever, a higher frequency of pruritus was found with Recommendations. The decision to use a particular epidural opioids. The literature is insufficient to evaluate anesthetic technique for cesarean delivery should be the impact of epidural opioids compared with intrave- individualized, based on several factors. These include nous PCA. In addition, the literature is insufficient to anesthetic, obstetric, or fetal risk factors (e.g., elective vs. evaluate spinal opioids compared with parenteral opi- emergency), the preferences of the patient, and the oids. The consultants strongly agree and the ASA mem- judgment of the anesthesiologist. Neuraxial techniques bers agree that neuraxial opioids for postoperative anal- are preferred to GA for most cesarean deliveries. An gesia improve analgesia and maternal satisfaction.
indwelling epidural catheter may provide equivalent on- Recommendations. For postoperative analgesia after set of anesthesia compared with initiation of spinal an- neuraxial anesthesia for cesarean delivery, neuraxial opi- esthesia for urgent cesarean delivery. If spinal anesthesia oids are preferred over intermittent injections of paren- is chosen, pencil-point spinal needles should be used instead of cutting-bevel spinal needles. However, GAmay be the most appropriate choice in some circum-stances (e.g., profound fetal bradycardia, ruptured uterus, severe hemorrhage, severe placental abruption).
There is insufficient literature to evaluate the benefits Uterine displacement (usually left displacement) should of neuraxial anesthesia compared with GA for postpar- be maintained until delivery regardless of the anesthetic tum tubal ligation. In addition, the literature is insuffi- cient to evaluate the impact of the timing of a postpar- Intravenous Fluid Preloading. The literature sup-
tum tubal ligation on maternal outcome. The consultants ports and the consultants and ASA members agree that and ASA members both agree that neuraxial anesthesia intravenous fluid preloading for spinal anesthesia re- for postpartum tubal ligation reduces complications duces the frequency of maternal hypotension when compared with GA. The ASA members are equivocal but the consultants agree that a postpartum tubal ligation Recommendations. Intravenous fluid preloading may within 8 h of delivery does not increase maternal com- be used to reduce the frequency of maternal hypoten- sion after spinal anesthesia for cesarean delivery. Al- Recommendations. For postpartum tubal ligation, though fluid preloading reduces the frequency of mater- the patient should have no oral intake of solid foods nal hypotension, initiation of spinal anesthesia should within 6 – 8 h of the surgery, depending on the type of not be delayed to administer a fixed volume of intrave- food ingested (e.g., fat content).࿣ Aspiration prophy- laxis should be considered. Both the timing of the Ephedrine or Phenylephrine. The literature sup-
procedure and the decision to use a particular anes- ports the administration of ephedrine and suggests that phenylephrine is effective in reducing maternal hypoten- i.e., neuraxial vs. general) should be sion during neuraxial anesthesia for cesarean delivery.
individualized, based on anesthetic risk factors, obstet- The literature is equivocal regarding the relative fre- ric risk factors (e.g., blood loss), and patient prefer- quency of patients with breakthrough hypotension ences. However, neuraxial techniques are preferred to when infusions of ephedrine are compared with phen- GA for most postpartum tubal ligations. The anesthe- ylephrine; however, lower umbilical cord pH values are siologist should be aware that gastric emptying will be reported after ephedrine administration. The consultants delayed in patients who have received opioids during agree and the ASA members strongly agree that ephed- labor, and that an epidural catheter placed for labor rine is acceptable for treating hypotension during may be more likely to fail with longer postdelivery neuraxial anesthesia. The consultants strongly agree and time intervals. If a postpartum tubal ligation is to be the ASA members agree that phenylephrine is an accept- performed before the patient is discharged from the able agent for the treatment of hypotension.
hospital, the procedure should not be attempted at a Recommendations. Intravenous ephedrine and phen- time when it might compromise other aspects of pa- ylephrine are both acceptable drugs for treating hypo- tient care on the labor and delivery unit.
Table 1. Suggested Resources for Obstetric Hemorrhagic
Table 2. Suggested Resources for Airway Management during
Emergencies
Initial Provision of Neuraxial Anesthesia
● Suction source with tubing and catheters ● Equipment for infusing intravenous fluids and blood products ● Self-inflating bag and mask for positive-pressure ventilation rapidly. Examples include, but are not limited to, hand- ● Medications for blood pressure support, muscle relaxation, and squeezed fluid chambers, hand-inflated pressure bags, and The items listed represent suggestions. The items should be customized tomeet the specific needs, preferences, and skills of the practitioner and health- The items listed represent suggestions. The items should be customized to meet the specific needs, preferences, and skills of the practitioner and health-care facility.
VII. Management of Obstetric and Anesthetic strongly agree that the immediate availability of equip- ment for the management of airway emergencies re- Resources for Management of Hemorrhagic
duces maternal, fetal, and neonatal complications.
Emergencies. Observational studies and case reports
Recommendations. Labor and delivery units should suggest that the availability of resources for hemorrhagic have personnel and equipment readily available to man- emergencies may be associated with reduced maternal age airway emergencies, to include a pulse oximeter and complications. The consultants and ASA members both qualitative carbon dioxide detector, consistent with the strongly agree that the availability of resources for man- ASA Practice Guidelines for Management of the Difficult aging hemorrhagic emergencies reduces maternal com- Airway.** Basic airway management equipment should be immediately available during the provision of Recommendations. Institutions providing obstetric neuraxial analgesia (table 2). In addition, portable equip- care should have resources available to manage hemor- ment for difficult airway management should be readily rhagic emergencies (table 1). In an emergency, the use available in the operative area of labor and delivery units of type-specific or O negative blood is acceptable. In (table 3). The anesthesiologist should have a preformu- cases of intractable hemorrhage when banked blood is lated strategy for intubation of the difficult airway. When not available or the patient refuses banked blood, intra- tracheal intubation has failed, ventilation with mask and operative cell-salvage should be considered if available.
cricoid pressure, or with a laryngeal mask airway or Invasive
Hemodynamic
Monitoring.
supraglottic airway device (e.g., Combitube®, Intubating There is insufficient literature to examine whether pulmo-nary artery catheterization is associated with improved ma- Table 3. Suggested Contents of a Portable Storage Unit for
ternal, fetal, or neonatal outcomes in patients with preg- Difficult Airway Management for Cesarean Delivery Rooms
nancy-related hypertensive disorders. The literature is silent ● Rigid laryngoscope blades of alternate design and size from regarding the management of obstetric patients with cen- tral venous catheterization alone. The consultants and ASA members agree that the routine use of central venous or ● Endotracheal tube guides. Examples include, but are not limited pulmonary artery catheterization does not reduce maternal to, semirigid stylets with or without a hollow core for jet complications in severely preeclamptic patients.
ventilation, light wands, and forceps designed to manipulate the Recommendations. The decision to perform invasive hemodynamic monitoring should be individualized and ● At least one device suitable for emergency nonsurgical airway based on clinical indications that include the patient’s ventilation. Examples include, but are not limited to, a hollow jet medical history and cardiovascular risk factors. The Task ventilation stylet with a transtracheal jet ventilator, and a Force recognizes that not all practitioners have access to supraglottic airway device (e.g., Combitube®, Intubating LMA resources for use of central venous or pulmonary artery ● Equipment suitable for emergency surgical airway access (e.g., Equipment for Management of Airway Emergen-
cies. Case reports suggest that the availability of equip-
ment for the management of airway emergencies may be ● Topical anesthetics and vasoconstrictors associated with reduced maternal, fetal, and neonatalcomplications. The consultants and ASA members both The items listed represent suggestions. The items should be customized tomeet the specific needs, preferences, and skills of the practitioner and health-care facility.
** American Society of Anesthesiologists Task Force on Management of the Adapted from Practice guidelines for management of the difficult airway: An Difficult Airway: Practice guidelines for management of the difficult airway: An updated report by the American Society of Anesthesiologists Task Force on updated report. ANESTHESIOLOGY 2003; 98:1269 –77.
Management of the Difficult Airway. ANESTHESIOLOGY 2003; 98:1269–77.
LMA [Fastrach™]) should be considered for maintaining previous uterine surgery), and local institutional policies; a routine an airway and ventilating the lungs. If it is not possible to blood cross-match is not necessary for healthy and uncomplicatedparturients ventilate or awaken the patient, an airway should be The fetal heart rate should be monitored by a qualified individual before and after administration of neuraxial analgesia for labor; con- Cardiopulmonary Resuscitation. The literature is
tinuous electronic recording of the fetal heart rate may not be insufficient to evaluate the efficacy of cardiopulmonary necessary in every clinical setting and may not be possible during resuscitation in the obstetric patient during labor and delivery. In cases of cardiac arrest, the American HeartAssociation has stated that 4 –5 min is the maximum time rescuers will have to determine whether the arrest can Oral intake of modest amounts of clear liquids may be allowed for be reversed by Basic Life Support and Advanced Cardiac Life Support interventions.†† Delivery of the fetus may The uncomplicated patient undergoing elective cesarean delivery improve cardiopulmonary resuscitation of the mother by may have modest amounts of clear liquids up to 2 h before inductionof anesthesia relieving aortocaval compression. The American Heart The volume of liquid ingested is less important than the presence of Association further notes that “the best survival rate for particulate matter in the liquid ingested infants Ͼ24 to 25 weeks in gestation occurs when the Patients with additional risk factors for aspiration (e.g., morbid obe- delivery of the infant occurs no more than 5 min after sity, diabetes, difficult airway) or patients at increased risk for oper- the mother’s heart stops beating. This typically requires ative delivery (e.g., nonreassuring fetal heart rate pattern) may havefurther restrictions of oral intake, determined on a case-by-case basis that the provider begin the hysterotomy about 4 min Solid foods should be avoided in laboring patients after cardiac arrest.”†† The consultants and ASA mem- Patients undergoing elective surgery (e.g., scheduled cesarean deliv- bers both strongly agree that the immediate availability ery or postpartum tubal ligation) should undergo a fasting period for of basic and advanced life-support equipment in the solids of 6 – 8 h depending on the type of food ingested (e.g., fat labor and delivery suite reduces maternal, fetal, and Before surgical procedures (i.e., cesarean delivery, postpartum tuballigation), practitioners should consider timely administration of non- Recommendations. Basic and advanced life-support particulate antacids, H receptor antagonists, and/or metoclopramide equipment should be immediately available in the oper- ative area of labor and delivery units. If cardiac arrestoccurs during labor and delivery, standard resuscitative III. Anesthetic Care for Labor and Delivery measures should be initiated. In addition, uterine dis- Neuraxial Techniques: Availability of Resources.
placement (usually left displacement) should be main-tained. If maternal circulation is not restored within 4 When neuraxial techniques that include local anesthetics are chosen, min, cesarean delivery should be performed by the ob- appropriate resources for the treatment of complications (e.g., hypo-tension, systemic toxicity, high spinal anesthesia) should be available If an opioid is added, treatments for related complications (e.g.,pruritus, nausea, respiratory depression) should be available An intravenous infusion should be established before the initiation of Appendix 1: Summary of Recommendations
neuraxial analgesia or anesthesia and maintained throughout theduration of the neuraxial analgesic or anesthetic Administration of a fixed volume of intravenous fluid is not requiredbefore neuraxial analgesia is initiated Conduct a focused history and physical examination before provid-ing anesthesia care Timing of Neuraxial Analgesia and Outcome of Labor.
Neuraxial analgesia should not be withheld on the basis of achieving an arbitrary cervical dilation, and should be offered on an individu- alized basis when this service is available Patients may be reassured that the use of neuraxial analgesia does not - Back examination when neuraxial anesthesia is planned or increase the incidence of cesarean delivery Neuraxial Analgesia and Trial of Labor after Previous Cesar-
A communication system should be in place to encourage early and ean Delivery.
ongoing contact between obstetric providers, anesthesiologists, andother members of the multidisciplinary team Neuraxial techniques should be offered to patients attempting vagi- Order or require a platelet count based on a patient’s history, phys- nal birth after previous cesarean delivery ical examination, and clinical signs; a routine intrapartum platelet For these patients, it is also appropriate to consider early placement count is not necessary in the healthy parturient of a neuraxial catheter that can be used later for labor analgesia or for Order or require an intrapartum blood type and screen or cross- anesthesia in the event of operative delivery match based on maternal history, anticipated hemorrhagic complica-tions (e.g., placenta accreta in a patient with placenta previa and Early Insertion of Spinal or Epidural Catheter for Compli-
cated Parturients.
Early insertion of a spinal or epidural catheter for obstetric (e.g., twin †† 2005 American Heart Association guidelines for cardiopulmonary resusci- tation and emergency cardiovascular care. Circulation 2005; 112(suppl):IV1–203.
gestation or preeclampsia) or anesthetic indications (e.g., anticipated difficult airway or obesity) should be considered to reduce the need general endotracheal anesthesia with halogenated agents for uterine for general anesthesia if an emergent procedure becomes necessary relaxation during removal of retained placental tissue - In these cases, the insertion of a spinal or epidural catheter may - Initiating treatment with incremental doses of intravenous or precede the onset of labor or a patient’s request for labor analgesia sublingual (i.e., metered dose spray) nitroglycerin may relax theuterus sufficiently while minimizing potential complications Continuous Infusion Epidural (CIE) Analgesia.
The selected analgesic/anesthetic technique should reflect patientneeds and preferences, practitioner preferences or skills, and avail- V. Anesthetic Choices for Cesarean Delivery Equipment, facilities, and support personnel available in the labor CIE may be used for effective analgesia for labor and delivery and delivery operating suite should be comparable to those available When a continuous epidural infusion of local anesthetic is selected,an opioid may be added to reduce the concentration of local anes- thetic, improve the quality of analgesia, and minimize motor block - Resources for the treatment of potential complications (e.g., Adequate analgesia for uncomplicated labor and delivery should be failed intubation, inadequate analgesia, hypotension, respiratory administered with the secondary goal of producing as little motor depression, pruritus, vomiting) should be available in the labor block as possible by using dilute concentrations of local anesthetics - Appropriate equipment and personnel should be available to The lowest concentration of local anesthetic infusion that provides care for obstetric patients recovering from major neuraxial or adequate maternal analgesia and satisfaction should be administered Single-injection Spinal Opioids with or without Local Anes-
The decision to use a particular anesthetic technique should be thetics.
individualized based on anesthetic, obstetric, or fetal risk factors (e.g.,elective vs. emergency), the preferences of the patient, and the Single-injection spinal opioids with or without local anesthetics may be used to provide effective, although time-limited, analgesia forlabor when spontaneous vaginal delivery is anticipated - Neuraxial techniques are preferred to general anesthesia for most If labor is expected to last longer than the analgesic effects of the spinal drugs chosen or if there is a good possibility of operativedelivery, a catheter technique instead of a single injection technique An indwelling epidural catheter may provide equivalent onset of anesthesia compared with initiation of spinal anesthesia for urgentcesarean delivery A local anesthetic may be added to a spinal opioid to increaseduration and improve quality of analgesia If spinal anesthesia is chosen, pencil-point spinal needles should beused instead of cutting-bevel spinal needles Pencil-point Spinal Needles.
General anesthesia may be the most appropriate choice in somecircumstances (e.g., profound fetal bradycardia, ruptured uterus, se- Pencil-point spinal needles should be used instead of cutting-bevel vere hemorrhage, severe placental abruption) spinal needles to minimize the risk of post– dural puncture headache Uterine displacement (usually left displacement) should be main- Combined Spinal–Epidural (CSE) Anesthetics.
tained until delivery regardless of the anesthetic technique used Intravenous fluid preloading may be used to reduce the frequency of CSE techniques may be used to provide effective and rapid analgesia maternal hypotension after spinal anesthesia for cesarean delivery Initiation of spinal anesthesia should not be delayed to administer afixed volume of intravenous fluid Patient-controlled Epidural Analgesia (PCEA).
Intravenous ephedrine and phenylephrine are both acceptable drugsfor treating hypotension during neuraxial anesthesia PCEA may be used to provide an effective and flexible approach forthe maintenance of labor analgesia - In the absence of maternal bradycardia, phenylephrine may be PCEA may be preferable to CIE for providing fewer anesthetic inter- preferable because of improved fetal acid– base status in uncom- ventions, reduced dosages of local anesthetics, and less motor block- ade than fixed-rate continuous epidural infusions PCEA may be used with or without a background infusion For postoperative analgesia after neuraxial anesthesia for cesareandelivery, neuraxial opioids are preferred over intermittent injectionsof parenteral opioids In general, there is no preferred anesthetic technique for removal of For postpartum tubal ligation, the patient should have no oral intake - If an epidural catheter is in place and the patient is hemodynam- of solid foods within 6 – 8 h of the surgery, depending on the type of ically stable, epidural anesthesia is preferable Aspiration prophylaxis should be considered Hemodynamic status should be assessed before administering Both the timing of the procedure and the decision to use a particular anesthetic technique (i.e., neuraxial vs. general) should be individu- Aspiration prophylaxis should be considered alized, based on anesthetic risk factors, obstetric risk factors (e.g., Sedation/analgesia should be titrated carefully due to the potential risks of respiratory depression and pulmonary aspiration during the Neuraxial techniques are preferred to general anesthesia for most In cases involving major maternal hemorrhage, general anesthesiawith an endotracheal tube may be preferable to neuraxial anesthesia - Be aware that gastric emptying will be delayed in patients who have Nitroglycerin may be used as an alternative to terbutaline sulfate or received opioids during labor and that an epidural catheter placed for labor may be more likely to fail with longer postdelivery time i. A directed history and physical examination ii. Communication between anesthetic and obstetric providers If a postpartum tubal ligation is to be performed before the patient is iii. A routine intrapartum platelet count does not reduce maternal discharged from the hospital, the procedure should not be attempted at a time when it might compromise other aspects of patient care on iv. For suspected preeclampsia or coagulopathy an intrapartum v. An intrapartum blood type and screen for all parturients reduces VII. Management of Obstetric and Anesthetic vi. For healthy and uncomplicated parturients, a blood cross-match vii. Perianesthetic recording of the fetal heart rate reduces fetal and Institutions providing obstetric care should have resources available - In an emergency, the use of type-specific or O negative blood is 2. Aspiration Prophylaxis in the Obstetric Patient i. Oral intake of clear liquids during labor improves patient comfort - In cases of intractable hemorrhage when banked blood is not and satisfaction but does not increase maternal complications available or the patient refuses banked blood, intraoperative ii. Oral intake of solids during labor increases maternal complica- cell-salvage should be considered if available - The decision to perform invasive hemodynamic monitoring iii. A fasting period for solids of 6 – 8 h before an elective cesarean should be individualized and based on clinical indications that include the patient’s medical history and cardiovascular risk iv. Nonparticulate antacids versus no antacids before operative pro- cedures (excluding operative vaginal delivery) reduces maternalcomplications Labor and delivery units should have personnel and equipmentreadily available to manage airway emergencies, to include a pulse 3. Anesthetic Care for Labor and Delivery§§ oximeter and qualitative carbon dioxide detector, consistent with the ASA Practice Guidelines for Management of the Difficult Airway a. Prophylactic spinal or epidural catheter insertion for compli- cated parturients reduces maternal complications - Basic airway management equipment should be immediately b. Continuous epidural infusion of local anesthetics with or available during the provision of neuraxial analgesia without opioids versus parenteral opioids - Portable equipment for difficult airway management should be c. Continuous epidural infusion of local anesthetics with or readily available in the operative area of labor and delivery units without opioids versus spinal opioids with or without local - The anesthesiologist should have a preformulated strategy for d. Induction of epidural analgesia using local anesthetics with - When tracheal intubation has failed, ventilation with mask and opioids versus equal concentrations of epidural local anes- cricoid pressure, or with a laryngeal mask airway or supraglottic airway device (e.g., Combitube®, Intubating LMA [Fastrach™]) e. Induction of epidural analgesia using local anesthetics with should be considered for maintaining an airway and ventilating opioids versus higher concentrations of epidural local anes- - If it is not possible to ventilate or awaken the patient, an airway f. Maintenance of epidural infusion of lower concentrations of local anesthetics with opioids versus higher concentrationsof local anesthetics without opioids (e.g., bupivacaine con- Basic and advanced life-support equipment should be immediately centrations Ͻ 0.125% with opioids vs. concentrations Ͼ available in the operative area of labor and delivery units If cardiac arrest occurs during labor and delivery, standard resuscita- g. Single-injection spinal opioids with or without local anesthet- h. Single-injection spinal opioids with local anesthetics versus - Uterine displacement (usually left displacement) should be main- - If maternal circulation is not restored within 4 min, cesarean ii. Combined spinal– epidural (CSE) techniques delivery should be performed by the obstetrics team a. CSE local anesthetics with opioids versus epidural local an- iii. Patient-controlled epidural analgesia (PCEA) a. PCEA versus continuous infusion epidurals Appendix 2: Methods and Analyses
b. PCEA with a background infusion versus PCEA without a The scientific assessment of these Guidelines was based on evidence iv. Neuraxial analgesia, timing of initiation, and progress of labor linkages or statements regarding potential relationships between clin- a. Administering epidural analgesia at cervical dilations of Ͻ 5 ical interventions and outcomes. The interventions listed below were examined to assess their impact on a variety of outcomes related to b. Neuraxial techniques for patients attempting vaginal birth ‡‡ Unless otherwise specified, outcomes for the listed interventions refer to the reduction of maternal, fetal, and neonatal complications.
i. If an epidural catheter is in situ and the patient is hemodynamically stable, epidural anesthesia is preferred over general or spinal anes- §§ Additional outcomes include improved analgesia, analgesic use, maternal thesia to improve the success at removing retained placenta ii. In cases involving major maternal hemorrhage, general anes- tinuous infusion epidurals, (7) general anesthesia versus epidural an- thesia is preferred over neuraxial anesthesia to reduce maternal esthesia for cesarean delivery, (8) CSE anesthesia versus epidural an- esthesia for cesarean delivery, (9) use of pencil-point spinal needlesversus cutting-bevel spinal needles, (10) ephedrine or phenylephrine iii. Administration of nitroglycerin for uterine relaxation improves reduces maternal hypotension during neuraxial anesthesia, and (11) neuraxial opioids versus parenteral opioids for postoperative analgesiaafter neuraxial anesthesia for cesarean delivery.
5. Anesthetic Choices for Cesarean Delivery General variance-based effect-size estimates or combined probability i. Equipment, facilities, and support personnel available in the tests were obtained for continuous outcome measures, and Mantel- labor and delivery suite should be comparable to that available Haenszel odds ratios were obtained for dichotomous outcome measures.
Two combined probability tests were used as follows: (1) the Fisher ii. General anesthesia versus epidural anesthesia combined test, producing chi-square values based on logarithmic trans- iii. General anesthesia versus spinal anesthesia formations of the reported P values from the independent studies, and (2) iv. Epidural anesthesia versus spinal anesthesia the Stouffer combined test, providing weighted representation of the v. CSE anesthesia versus epidural anesthesia studies by weighting each of the standard normal deviates by the size of vi. CSE anesthesia versus spinal anesthesia the sample. An odds ratio procedure based on the Mantel-Haenszel vii. Use of pencil-point spinal needles versus cutting-bevel spinal method for combining study results using 2 ϫ 2 tables was used with outcome frequency information. An acceptable significance level was set viii. Intravenous fluid preloading versus no intravenous fluid pre- at P Ͻ 0.01 (one-tailed). Tests for heterogeneity of the independent loading for spinal anesthesia reduces maternal hypotension studies were conducted to assure consistency among the study results.
ix. Ephedrine or phenylephrine reduces maternal hypotension dur- DerSimonian-Laird random-effects odds ratios were obtained when signif- icant heterogeneity was found (P Ͻ 0.01). To control for potential pub- x. Neuraxial opioids versus parenteral opioids for postoperative lishing bias, a “fail-safe n” value was calculated. No search for unpublished analgesia after neuraxial anesthesia for cesarean delivery studies was conducted, and no reliability tests for locating research resultswere done.
Meta-analytic results are reported in table 4. To be accepted as i. Neuraxial anesthesia versus general anesthesia significant findings, Mantel-Haenszel odds ratios must agree with com- ii. A postpartum tubal ligation within 8 h of delivery does not bined test results whenever both types of data are assessed. In the absence of Mantel-Haenszel odds ratios, findings from both the Fisherand weighted Stouffer combined tests must agree with each other to Interobserver agreement among Task Force members and two meth- i. Availability of resources for management of hemorrhagic emer- odologists was established by interrater reliability testing. Agreement levels using a ␬ statistic for two-rater agreement pairs were as follows: ii. Immediate availability of equipment for management of airway (1) type of study design, ␬ ϭ 0.83– 0.94; (2) type of analysis, ␬ ϭ 0.71– 0.93; (3) evidence linkage assignment, ␬ ϭ 0.87–1.00; and (4) iii. Immediate availability of basic and advanced life-support equip- literature inclusion for database, ␬ ϭ 0.74 –1.00. Three-rater chance- iv. Invasive hemodynamic monitoring for severely preeclamptic corrected agreement values were (1) study design, Sav ϭ 0.884, Var (Sav) ϭ 0.004; (2) type of analysis, Sav ϭ 0.805, Var (Sav) ϭ 0.009; (3) Scientific evidence was derived from aggregated research literature, linkage assignment, Sav ϭ 0.911, Var (Sav) ϭ 0.002; and (4) literature and opinion-based evidence was obtained from surveys, open presen- database inclusion, Sav ϭ 0.660, Var (Sav) ϭ 0.024. These values tations, and other activities (e.g., Internet posting). For purposes of represent moderate to high levels of agreement.
literature aggregation, potentially relevant clinical studies were identi- Consensus was obtained from multiple sources, including (1) survey fied via electronic and manual searches of the literature. The elec- opinion from consultants who were selected based on their knowledge tronic and manual searches covered a 67-yr period from 1940 through or expertise in obstetric anesthesia or maternal and fetal medicine, (2) 2006. More than 4,000 citations were initially identified, yielding a total survey opinions solicited from active members of the ASA, (3) testi- of 2,986 nonoverlapping articles that addressed topics related to the mony from attendees of publicly held open forums at two national evidence linkages. After review of the articles, 2,549 studies did not anesthesia meetings, (4) Internet commentary, and (5) Task Force provide direct evidence and were subsequently eliminated. A total of opinion and interpretation. The survey rate of return was 75% (n ϭ 76 437 articles contained direct linkage-related evidence.
of 102) for the consultants, and 2,326 surveys were received from Initially, each pertinent outcome reported in a study was classified as active ASA members. Results of the surveys are reported in tables 5 and supporting an evidence linkage, refuting a linkage, or equivocal. The 6 and in the text of the Guidelines.
results were then summarized to obtain a directional assessment for The consultants were asked to indicate which, if any, of the evi- each evidence linkage before conducting a formal meta-analysis. Liter- dence linkages would change their clinical practices if the Guidelines ature pertaining to 11 evidence linkages contained enough studies were instituted. The rate of return was 35% (n ϭ 36). The percent of with well-defined experimental designs and statistical information suf- responding consultants expecting no change associated with each ficient for meta-analyses. These linkages were (1) nonparticulate ant- linkage were as follows: perianesthetic evaluation—97%; aspiration acids versus no antacids, (2) continuous epidural infusion of local prophylaxis— 83%; anesthetic care for labor and delivery— 89%; re- anesthetics with or without opioids versus parenteral opioids, (3) moval of retained placenta—97%; anesthetic choices for cesarean de- induction of epidural analgesia using local anesthetics with opioids livery—97%; postpartum tubal ligation—97%; and management of versus equal concentrations of epidural local anesthetics without opi- complications—94%. Ninety-seven percent of the respondents indi- oids, (4) maintenance of epidural infusion of lower concentrations of cated that the Guidelines would have no effect on the amount of time local anesthetics with opioids versus higher concentrations of local spent on a typical case. One respondent indicated that there would be anesthetics without opioids, (5) CSE local anesthetics with opioids an increase of 5 min in the amount of time spent on a typical case with versus epidural local anesthetics with opioids, (6) PCEA versus con- the implementation of these Guidelines.
Table 4. Meta-analysis Summary
Aspiration Prophylaxis
Nonparticulate antacids vs. no antacids Metoclopramide vs. no metoclopramide Anesthetic Care for Labor and Vaginal Delivery
CIE local anesthetics Ϯ opioids vs. IV opioids Epidural induction LAϩO vs. equal LA doses Epidural maintenance LAϩO vs. higher LA doses Pencil-point vs. cutting-bevel spinal needles PCEA with background infusion vs. PCEA Table 4. Continued
Anesthetic Choices for Cesarean Delivery
Fluid preloading vs. no preloading Neuraxial vs. parenteral O for postoperative analgesia * Nonrandomized comparative studies included in analysis.
† DerSimonian-Laird random effects odds ratio (OR).
CI ϭ confidence interval; CIE ϭ continuous infusion epidural; CSE ϭ combined spinal–epidural; GA ϭ general anesthesia; IV ϭ intravenous; LA ϭ localanesthetics; LAϩO ϭ local anesthetics with opioids; NS ϭ not significant; O ϭ opioids; PCEA ϭ patient-controlled epidural analgesia.
Table 5. Consultant Survey Responses
Perianesthetic Evaluation
1. Directed history and physical examination reduces maternal, fetal, and neonatal complications 2. Communication between anesthetic and obstetric providers reduces maternal, fetal, and neonatal 3. A routine intrapartum platelet count does not reduce maternal anesthetic complications
4. An intrapartum platelet count reduces maternal anesthetic complications: 5. All parturients should have an intrapartum blood sample sent to the blood bank to reduce maternal 6. Perianesthetic recording of the fetal heart rate reduces fetal and neonatal complications Aspiration Prophylaxis
7a. Oral intake of clear liquids during labor improves patient comfort and satisfaction 7b. Oral intake of clear liquids during labor does not increase maternal complications
8a. Oral intake of solids during labor increases maternal complications 8b. The patient undergoing elective cesarean delivery should undergo a fasting period for solids of 6–8 h depending on the type of food ingested (e.g., fat content) 8c. The patient undergoing elective postpartum tubal ligation should undergo a fasting period for solids of 6–8 h depending on the type of food ingested (e.g., fat content) 9. Administration of a nonparticulate antacid before operative procedures reduces maternal complications Anesthetic Care for Labor and Delivery
Neuraxial techniques:
10. Prophylactic spinal or epidural catheter insertion for complicated parturients reduces maternal 11. Continuous epidural infusion using local anesthetics with or without opioids vs. parenteral opioids:
Decreases the chance of spontaneous delivery
Increases fetal and neonatal side effects 12. Continuous epidural infusion using local anesthetics with or without opioids vs. spinal opioids with or
Decreases the chance of spontaneous delivery
Increases fetal and neonatal side effects 13a. Induction of epidural analgesia using local anesthetics with opioids vs. epidural analgesia with equal
concentrations of local anesthetics without opioids:
Increases fetal and neonatal side effects 13b. Induction of epidural analgesia using low-dose local anesthetics with opioids vs. higher concentrations of epidural local anesthetics without opioids: Increases fetal and neonatal side effects 14a. Maintenance of epidural infusion of lower concentrations of local anesthetics with opioids vs. higher
concentrations of local anesthetics without opioids: Reduces the duration of labor
Improves the chance of spontaneous delivery Reduces maternal motor block
Reduces maternal side effects
Reduces fetal and neonatal side effects
14b. Maintenance of epidural analgesia using bupivacaine < 0.125% with opioids vs. bupivacaine
concentrations > 0.125% without opioids:
Reduces the duration of labor
Improves the chance of spontaneous delivery Reduces maternal motor block
Reduces maternal side effects
Reduces fetal and neonatal side effects
Table 5. Continued
15. Single-injection spinal opioids with or without local anesthetics vs. parenteral opioids:
Decrease the chance of spontaneous delivery
16. Single-injection spinal opioids with local anesthetics vs. spinal opioids without local anesthetics:
Decrease the chance of spontaneous delivery
Combined spinal–epidural (CSE) techniques:
17. CSE local anesthetics with opioids vs. epidural local anesthetics with opioids:
Improve early analgesia
Improve overall analgesia
Decrease the duration of labor
Decrease the chance of spontaneous delivery
Reduce maternal motor block
Patient-controlled epidural analgesia (PCEA):
18. PCEA vs. continuous infusion epidurals: Reduces the need for anesthetic interventions
Increases the chance of spontaneous delivery Reduces maternal motor block
Decreases maternal side effects
19. PCEA with a background infusion vs. PCEA without a background infusion:
Reduces the need for anesthetic interventions
Decreases the chance of spontaneous delivery
Neuraxial Analgesia, Timing of Initiation, and Progress of Labor
20. Administering epidural analgesia at cervical dilations of Ͻ 5 centimeters (vs. Ն 5 cm): Reduces the duration of labor
Improves the chance of spontaneous delivery Increases fetal and neonatal side effects 21. Neuraxial techniques improve the likelihood of vaginal delivery for patients attempting vaginal birth after Removal of Retained Placenta
22. If an epidural catheter is in situ and the patient is hemodynamically stable, epidural anesthesia is the 23. In cases involving major maternal hemorrhage, a general endotracheal anesthetic is preferred over 24. Administration of nitroglycerin for uterine relaxation improves success at removing retained placenta Anesthetic Choices for Cesarean Delivery
25. Equipment, facilities, and support personnel available in the labor and delivery operating suite should be comparable to that available in the main operating suite 26. General anesthesia vs. epidural anesthesia: Reduces time to skin incision
Increases fetal and neonatal complications 27. General anesthesia vs. spinal anesthesia: Reduces time to skin incision
Increases fetal and neonatal complications Table 5. Continued
28. Epidural anesthesia vs. spinal anesthesia: Reduces quality of anesthesia
29. CSE anesthesia vs. epidural anesthesia: Reduces time to skin incision
Reduces maternal side effects
30. CSE anesthesia vs. spinal anesthesia: Increases flexibility for prolonged procedures Reduces maternal side effects
31. Use of pencil-point spinal needles vs. cutting-bevel spinal needles reduces maternal complications 32. Intravenous fluid preloading vs. no intravenous fluid preloading for spinal anesthesia reduces maternal 33a. Intravenous ephedrine is an acceptable agent to treat hypotension during neuraxial anesthesia 33b. Intravenous phenylephrine is an acceptable agent to treat hypotension during neuraxial anesthesia 34. Neuraxial opioids vs. parenteral opioids for postoperative analgesia after regional anesthesia for cesarean Postpartum Tubal Ligation
35. Neuraxial vs. general anesthesia reduces maternal complications
36. An immediate (Յ 8 h) postpartum tubal ligation does not increase maternal complications
Management of Complications
37. Availability of resources for management of hemorrhagic emergencies reduces maternal complications
38. Immediate availability of equipment for management of airway emergencies reduces maternal, fetal, and
39. Immediate availability of basic and advanced life-support equipment in the labor and delivery suite reduces maternal, fetal, and neonatal complications
40. Routine use of central venous or pulmonary artery catheterization reduces maternal complications in
n ϭ number of consultants who responded to each item.
Table 6. ASA Membership Survey Responses
Perianesthetic Evaluation
1. Directed history and physical examination reduces maternal, fetal, and neonatal complications 2. Communication between anesthetic and obstetric providers reduces maternal, fetal, and neonatal 3. A routine intrapartum platelet count does not reduce maternal anesthetic complications
4. An intrapartum platelet count reduces maternal anesthetic complications: 5. All parturients should have an intrapartum blood sample sent to the blood bank to reduce maternal 6. Perianesthetic recording of the fetal heart rate reduces fetal and neonatal complications Aspiration Prophylaxis
7a. Oral intake of clear liquids during labor improves patient comfort and satisfaction 7b. Oral intake of clear liquids during labor does not increase maternal complications
8a. Oral intake of solids during labor increases maternal complications 8b. The patient undergoing elective cesarean delivery should undergo a fasting period for solids of 6–8 h depending on the type of food ingested (e.g., fat content) 8c. The patient undergoing elective postpartum tubal ligation should undergo a fasting period for solids of 6–8 h depending on the type of food ingested (e.g., fat content) 9. Administration of a nonparticulate antacid before operative procedures reduces maternal complications Anesthetic Care for Labor and Delivery
Neuraxial techniques:
10. Prophylactic spinal or epidural catheter insertion for complicated parturients reduces maternal 11. Continuous epidural infusion using local anesthetics with or without opioids vs. parenteral opioids:
Decreases the chance of spontaneous delivery
Increases fetal and neonatal side effects 12. Continuous epidural infusion using local anesthetics with or without opioids vs. spinal opioids with or
Decreases the chance of spontaneous delivery
Increases fetal and neonatal side effects 13a. Induction of epidural analgesia using local anesthetics with opioids vs. epidural analgesia with equal
concentrations of local anesthetics without opioids:
Increases fetal and neonatal side effects 13b. Induction of epidural analgesia using low-dose local anesthetics with opioids vs. higher concentrations of epidural local anesthetics without opioids: Increases fetal and neonatal side effects 14a. Maintenance of epidural infusion of lower concentrations of local anesthetics with opioids vs. higher
concentrations of local anesthetics without opioids: Reduces the duration of labor
Improves the chance of spontaneous delivery Reduces maternal motor block
Reduces maternal side effects
Reduces fetal and neonatal side effects
14b. Maintenance of epidural analgesia using bupivacaine < 0.125% with opioids vs. bupivacaine
concentrations > 0.125% without opioids:
Reduces the duration of labor
Improves the chance of spontaneous delivery Reduces maternal motor block
Reduces maternal side effects
Reduces fetal and neonatal side effects
Table 6. Continued
15. Single-injection spinal opioids with or without local anesthetics vs. parenteral opioids:
Decrease the chance of spontaneous delivery
16. Single-injection spinal opioids with local anesthetics vs. spinal opioids without local anesthetics:
Decrease the chance of spontaneous delivery
Combined spinal–epidural (CSE) techniques:
17. CSE local anesthetics with opioids vs. epidural local anesthetics with opioids:
Improve early analgesia
Improve overall analgesia
Decrease the duration of labor
Decrease the chance of spontaneous delivery
Reduce maternal motor block
Patient-controlled epidural analgesia (PCEA):
18. PCEA vs. continuous infusion epidurals: Reduces the need for anesthetic interventions
Increases the chance of spontaneous delivery Reduces maternal motor block
Decreases maternal side effects
19. PCEA with a background infusion vs. PCEA without a background infusion:
Reduces the need for anesthetic interventions
Decreases the chance of spontaneous delivery
Neuraxial Analgesia, Timing of Initiation, and Progress of Labor
20. Administering epidural analgesia at cervical dilations of Ͻ 5 centimeters (vs. Ͼ 5 cm): Reduces the duration of labor
Improves the chance of spontaneous delivery Increases fetal and neonatal side effects 21. Neuraxial techniques improve the likelihood of vaginal delivery for patients attempting vaginal birth after Removal of Retained Placenta
22. If an epidural catheter is in situ and the patient is hemodynamically stable, epidural anesthesia is the 23. In cases involving major maternal hemorrhage, a general endotracheal anesthetic is preferred over 24. Administration of nitroglycerin for uterine relaxation improves success at removing retained placenta Anesthetic Choices for Cesarean Delivery
25. Equipment, facilities, and support personnel available in the labor and delivery operating suite should be comparable to that available in the main operating suite 26. General anesthesia vs. epidural anesthesia: Reduces time to skin incision
Increases fetal and neonatal complications 27. General anesthesia vs. spinal anesthesia: Reduces time to skin incision
Increases fetal and neonatal complications Table 6. Continued
28. Epidural anesthesia vs. spinal anesthesia: Reduces quality of anesthesia
29. CSE anesthesia vs. epidural anesthesia: Reduces time to skin incision
Reduces maternal side effects
30. CSE anesthesia vs. spinal anesthesia: Increases flexibility for prolonged procedures Reduces maternal side effects
31. Use of pencil-point spinal needles vs. cutting-bevel spinal needles reduces maternal complications 32. Intravenous fluid preloading vs. no intravenous fluid preloading for spinal anesthesia reduces maternal 33a. Intravenous ephedrine is an acceptable agent to treat hypotension during neuraxial anesthesia 33b. Intravenous phenylephrine is an acceptable agent to treat hypotension during neuraxial anesthesia 34. Neuraxial opioids vs. parenteral opioids for postoperative analgesia after regional anesthesia for cesarean Postpartum Tubal Ligation
35. Neuraxial vs. general anesthesia reduces maternal complications
36. An immediate (Յ 8 h) postpartum tubal ligation does not increase maternal complications
Management of Complications
37. Availability of resources for management of hemorrhagic emergencies reduces maternal complications
38. Immediate availability of equipment for management of airway emergencies reduces maternal, fetal, and
39. Immediate availability of basic and advanced life-support equipment in the labor and delivery suite reduces maternal, fetal, and neonatal complications
40. Routine use of central venous or pulmonary artery catheterization reduces maternal complications in
ASA ϭ American Society of Anesthesiologists; n ϭ number of members who responded to each item.

Source: http://anesthesiareferencesheets.com/files/ObstetricAnesthesia.pdf