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OBSTETRIC ANESTHESIA

Patient Preferences for Anesthesia Outcomes Associated with Cesarean Delivery

Brendan Carvalho, MBBCh, FRCA^*, Sheila E. Cohen, MB, ChB, FRCA^*, Steven S. Lipman, MD^*, Andrea Fuller, MD^*, Anbu D. Mathusamy, MD, and Alex Macario, MD^*

*Department of Anesthesia, Stanford University School of Medicine, Stanford, California; and Bronx-Lebanon Hospital, Bronx, New York

Address correspondence and reprint requests to Brendan Carvalho, MBBCh, FRCA, Department of Anesthesia, H3580, Stanford University School of Medicine, Stanford, CA 94305. Address e-mail to bcarvalho{at}stanford.edu.

	Abstract

Top Abstract Introduction Methods Results Discussion Appendix 1 Appendix 2 References

 
When deciding on neuraxial medication (e.g., spinal opioids) for cesarean delivery (CS) under regional anesthesia, anesthesiologists make treatment decisions that "trade off" relieving pain with the potential for increased risk of side effects. No previous studies have examined obstetric patients’ anesthesia preferences. Researchers administered 100 written surveys to pregnant women attending our institutions’ expectant parent class. We determined patients’ preferences for importance of specific intraoperative and postoperative anesthesia outcomes using priority ranking and relative value scales. We also explored patients’ fears, concerns, and tolerance regarding CS and analgesics. Eighty-two of 100 surveys were returned and analyzed. Pain during and after CS was the greatest concern followed by vomiting, nausea, cramping, pruritus, and shivering. Ranking and relative value scores were closely correlated (R² = 0.7). Patients would tolerate a visual analog pain score (0–100 mm) of 56 ± 22 before exposing their baby to the potential effects of analgesics they receive. In contrast to previous general surgical population surveys that found nausea and vomiting as primary concerns, we found pain during and after CS as parturients’ most important concern. Common side effects such as pruritus and shivering caused only moderate concern. This information should be used to guide anesthetic choices, e.g., inclusion of spinal opioids given in adequate doses.

	Introduction

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When providing regional anesthesia for cesarean delivery (CS), anesthesiologists make decisions about the use of certain neuraxial medication (e.g., spinal opioids, clonidine) which, although improving analgesia, may increase the risk of side effects. Most anesthesiologists prioritize pain relief as their primary concern and accept increased side effect profiles (1). In the traditional physician-oriented model of medical practice, patient preferences often are not discussed (2). However, most patients are anxious preoperatively and may fear anesthesia more than surgical complications (3). Moreover, anesthesiologists and surgeons poorly predict patients’ preoperative anxiety and fear (3).

We are unaware of any previous studies that examined obstetric patients’ anesthesia preferences before undergoing CS. Several studies of the preferences of general surgical patients undergoing general anesthesia indicate that patients may be prepared to tolerate pain in order to avoid nausea and vomiting (4–6), whereas others indicate pain is the primary concern for patients undergoing surgery (7–9). Obstetric patients are different from the general surgical population because of additional concerns about the baby’s exposure to anesthesia and different peripartum surgical recovery needs, including breast-feeding and caring for a newborn baby. Nausea and vomiting are very common pregnancy-related side effects and may also affect pregnant patients’ preferences for potential anesthesia outcomes compared with the general population. Furthermore, women tend to be more anxious about their anesthesia compared with men (7,9).

Awareness of patients’ needs and desires for pain relief and potential side effects is important when planning anesthetic care. Patient satisfaction and potentially the quality of medical care may be improved by addressing patients’ preferences for pain relief and anesthesia (2). The goal of this study was to determine patient preferences for anesthesia outcomes associated with CS.

	Methods

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After obtaining IRB approval and informed consent, we distributed 100 written questionnaires from August 2002 until January 2003. We approached pregnant women (n = 100) attending a prenatal class designed to educate patients about CS at Stanford University Hospital at random to participate in this study. No formal CS anesthesia education was given before the subjects took the survey. The preoperative visit and prenatal class are routine at our institution and are attended by any expectant mothers and not necessarily those scheduled for a CS. The study investigator explained the study and distributed a patient information sheet describing study aims and patient rights. Stanford University Hospital, California, performs 5300 deliveries per year and has a regional anesthesia rate for scheduled CS of >97%.

The survey collected standard demographic data including age, race, income, education, and marital status as well as information regarding previous experience with surgery and/or CS and related side effects of anesthesia.

A list of potential clinical anesthesia outcomes was derived from a complete list obtained from a computerized MEDLINE search using the term "anesthesia outcome, complication." The final list used was narrowed to 9 important items for purposes of the study plus a side effect-free recovery for a total of 10 outcomes (Appendix 1). These anesthesia outcomes were similar to a previous study by our research team on the general surgical population (5). The research team created simple descriptions to reflect a number of symptoms focused around a particular outcome; five senior board-certified anesthesiologists in our department reviewed and edited these descriptions for validity and accuracy. To determine women’s preferences for specific intraoperative and postoperative anesthesia outcomes and potential side effects, survey respondents were asked to rank the importance of these outcomes. Both priority ranking and relative value scales were used to overcome the difficulty of establishing patients’ subjective judgments of side effects that characterize anesthesia. To understand these ranking techniques, we gave patients detailed written instructions. For example, "rank each of these outcomes (you could experience any of these) in relation to each other from 1 to 10 from the most desirable (1) to the least desirable (10). Next, pretend that you are given $100 in order to prevent the following undesirable outcomes of anesthesia. Distribute the $100 such that the more money you spend on a condition, the less likely that it will occur. Thus, you should spend more money on outcomes you most want to avoid" (Appendix 1).

In addition to the above, we devised a "trade-off" table that forced patients to make choices between pain relief and common opioid-related side effects (nausea, vomiting, and pruritus). This table, derived from a group of expert obstetric anesthesiologists, allowed us to determine how parturients balance risk and benefit (Appendix 2). We gave subjects detailed written instructions to help them understand this "trade-off" table (Appendix 2).

We asked research participants how much pain (visual analog pain scale [VAPS] 0–100 mm, with 0 = no pain and 100 = the worse imaginable pain) they would tolerate before exposing their baby to any analgesic medication they may receive. We instructed research participants to, "Indicate on a line below (mark with X) how much pain you would tolerate rather than expose your baby to any medication you receive."

In addition, to determine the research participants’ fear of regional anesthesia for their CS, we asked patients, "What is your biggest fear with spinal/epidural anesthesia? Pain on insertion/Failure to provide pain relief/Paralysis/Backache/Headache/Other (please specify)."

An anesthesiologist involved in the study was available to answer any questions that arose while the survey was completed. Each question expressed only one idea (i.e., no questions contained "and") and no questions were phrased in a negative form.

Surveys were returned in a sealed mailbox to maintain anonymity. At that time, parturients were given a similar survey form with a postage-paid envelope, addressed to the study investigator, to take home and complete after their CS. The post-CS survey was less detailed and consisted of the same priority ranking and relative value scales and trade-off table as well as a section for reporting any side effects the patient experienced during their CS. Parturients were instructed to complete the survey during the 3- to 5-day hospitalization period after their CS. To determine internal validity of the survey instrument, we analyzed the association (i.e., correlation) between the relative value data and the ranking data for each outcome. We also determined that the normal (or side-effect-free) outcome was ranked highest and had the lowest relative value assigned to it.

We used descriptive statistics to summarize demographic and side-effect preference data. We used analyses of variance (ANOVA) followed by Dunnett’s tests for multiple comparisons to evaluate the significance of both ranking and relative value outcome data. Pearson’s correlation coefficients were used to calculate the correlation between the relative value data and the ranking data. ANOVAs were used to determine the effect of parity, education, household income, previous surgery or CS, and previous patient experience of a particular outcome on rank and relative value outcome data. We analyzed the data with SPSS (version 11) and Microsoft Excel using the appropriate statistical methods with P < 0.05 considered statistically significant.

	Results

Top Abstract Introduction Methods Results Discussion Appendix 1 Appendix 2 References

 
Of the 100 pre-CS surveys distributed, 93 were returned. Eleven of the surveys returned were incomplete and excluded from data analysis. Overall, 82 surveys were analyzed for an 82% response rate. Demographics of the 82 pre-CS questionnaires are presented in Table 1. The study population comprised mainly married, highly educated, Caucasian subjects (Table 1). Seventy-seven percent of parturients had undergone a previous surgical procedure and 24% had undergone a previous CS. Of the patients surveyed, 57% had previously experienced at least 1 of the clinical outcomes studied. Only 23 parturients completed the post-CS survey and, of these, only 15 were complete enough to analyze. All 15 of these patients returning the post-CS survey had their CS under spinal anesthesia and experienced one or more side effects after their CS.

In the pre-CS survey sample, pain during CS was the least desirable outcome by both the ranking and the relative value scores methodology (P < 0.001) (Table 2). The mean ranking and relative value scores produced the same rank of clinical outcome (Table 2). Furthermore, the ranking and relative value outcome scores for each outcome were positively and significantly correlated (R² ranged between 0.6–0.8 for the 9 outcome variables, P < 0.001) demonstrating good internal consistency. Of those surveyed, 49% ranked intraoperative pain as their most undesirable outcome. However, there was interindividual variability among the distribution of rankings of patients’ preferences for anesthesia outcomes (Table 3). Although the majority (77%) of patients surveyed expected pain after their CS, postoperative pain was an important outcome ranking second after intraoperative pain (Table 2). Of those patients expecting pain after their CS, 71% expected some pain, 26% moderate pain, and 3% severe postoperative pain. However, despite such concerns, there was a reluctance by parturients to receive postpartum analgesics. Overall, patients would tolerate a visual analog pain score (0–100 mm) of 56 ± 22 rather than expose their baby to any pain medication they received after their CS.

The post-CS survey had similar ranking and relative value score results, with pain during and after being the highest ranked, followed by vomiting, then nausea. Side effects such as shivering, cramping, itching, and sleepiness received similarly lower ratings as in the pre-CS survey.

Parity, patient education, household income, previous surgery or CS, and previous patient experience of a particular side effect or outcome did not impact significantly on current preferences. There was no statistically significant correlation between previous CS, previous surgery, or parity with the outcomes measured.

Possible paralysis was the principal fear with spinal and epidural anesthesia, expressed by >48% of patients surveyed. Failure to provide pain relief, headache, and pain on insertion were the principal fears in 17%, 15%, and 7% of patients, respectively.

When patients were asked to select a pain medication dose (smallest, moderate, or largest) in order to trade off pain relief and a proportional increase in possible side effects, 60% of patients chose the moderate dose, 32% the largest dose, and only 8% the smallest dose. Similarly, the dose/side effect trade-off selection in the post-CS survey showed 46% preferred the moderate dose, 36% the larger-dose medication, and only 18% selected the smaller dose.

	Discussion

Top Abstract Introduction Methods Results Discussion Appendix 1 Appendix 2 References

 
In this obstetric population study, we determined outcome preferences using both the ranking and the relative value scores methodology. Ranking and allocating monetary value to avoid unpleasant side effects have been used and validated in several previous studies (5,10–12). The current survey elicited data of patients’ preferences for clinical outcomes with high correlation between the ranking and relative value scores. Our finding that pain during and after CS ranked highest among undesirable clinical outcomes is similar to those of several previous studies of general surgical patients (7–10). A study of 350 ambulatory surgery patients surveyed preoperatively using similar methodology found that pain was the leading concern (10). In a previous survey of 800 general surgical patients, pain was ranked the highest concern, with nausea viewed as only a moderate concern (7). Similarly, pain was found to be a more specific fear compared with nausea and vomiting in other studies of preoperative patients undergoing general surgery (7–10).

Avoiding pain, rather than other side effects such as nausea, may seem to be an intuitive clinical end-point for anesthesia care providers. A panel of expert anesthesiologists considering which outcomes are most important to avoid, ranked incisional pain highest and above nausea and vomiting (1). However, avoiding postoperative nausea has been rated a primary concern in several survey studies in the general surgical population (4–6). In a previous survey at our institution, Macario et al. (5) used similar methodology in the general surgical population and found nausea and vomiting ranked as the least desirable outcome and primary concern. Similarly, Matthey et al. (6) found postoperative nausea and vomiting was of greater concern than pain in a survey of attitudes toward preoperative risks in the general population.

A potential limitation of this study is that the sample of parturients surveyed at our institution was highly educated and older than the average parturient in the United States. The study population also comprised married, predominantly Caucasian subjects. Patients’ preferences observed in our study may differ from other institutions and may not necessarily reflect national obstetric population preferences. Our patient population may not be typical of many obstetric units and this limitation may not allow other institutions with a less-educated patient base to extrapolate our findings to their practice. In addition, only approximately one-third of patients undergoing CS in our institution would have attended the prenatal classes, and patient preferences may differ within our institution between parturients attending and those not attending prenatal classes (class attendees tend to be higher educated than nonattendees). A similar population served by our institution was studied in a previous, methodologically similar survey in the general surgical population, so we believe that comparisons between the obstetric preference data and general surgical preference data are valid (5).

Although we found that parity, previous surgery, and CS did not impact significantly on preferences, this study was not designed to determine the impact of these factors on preferences for clinical outcomes. More patients would be required in order to evaluate this relationship. However, the findings of poor correlation between previous experience of clinical outcomes is similar to other patient preference studies (5,9,10,13). Kindler et al. (9) found that young female patients with no previous or a negative experience had the highest anxiety scores before a surgical procedure. Women are more likely to express fear and anxiety for anesthesia outcomes (7,13) and are twice as likely to report any postoperative side effects and complications (14). Most of our women participants were of similar age and married, and thus differences in preferences with age and partner support could not be determined. Gan et al. (12) found a correlation between increasing age, income, and being married, and increased willingness to pay to avoid nausea and vomiting. Jenkins et al. (10) showed that older patients attributed less importance to adverse clinical outcomes. Because our research population consisted predominantly of highly educated individuals of higher socioeconomic standing, this did not allow us to explore the relationships among patient education, household income, and patient preferences. However, other studies have found that education and occupation did not markedly affect patients’ concern for anesthesia (7,13).

Physicians and patients may have different perspectives regarding treatment outcomes. Optimal management of acute pain often depends on patients’ willingness to trade off pain control and treatment of side effects. In this study, the majority of parturients chose the moderate analgesic dose. This analgesic dose-selection table asked parturients to make a treatment decision similar to that of an anesthesiologist in trading off improved pain control with increased potential for side effects. Our findings are in keeping with an adaptive conjoint analysis of patients’ preferences for acute pain that found pain and side effects had equal importance scores among patients (15).

The post-CS survey produced similar results to our pre-CS survey. However, because of the poor response rate, findings and conclusions from the post-CS data should be guarded. The impact of the CS on our patients’ preferences cannot be fully evaluated or adequately interpreted because of the small post-CS survey response rate. The small post-CS survey response rate was possibly attributable to many parturients not having undergone a CS. In addition, the long time interval between the pre- and post-CS survey and our reliance on participants to complete and mail their surveys to the study investigators after delivery of their baby may have contributed to the poor response rate.

Almost half of the parturients surveyed expressed fear of paralysis as their principal fear with spinal or epidural anesthesia. This finding is higher than previously reported (7). Despite the extremely remote chance of this complication, this finding reinforces the notion that patients’ fears should be addressed during the preoperative evaluation.

Our study indicated that parturients are reluctant to receive postpartum analgesics because of the potential medication impact on their baby. Research participants reported they would tolerate moderate pain (VAPS 0–100 mm of 56 ± 22) rather than expose their baby to any pain medication they received after their CS. This finding illustrates the importance of patient education about breast-feeding and postoperative analgesics in this population.

This study adds to our understanding of how patients value various clinical outcomes associated with anesthesia for CS. Adequate anesthesia and analgesia are clearly the most important outcome for the majority of obstetric patients compared with the general surgical population. However, maternal reluctance to receive analgesic medication for concern of transfer to her infant must be considered when prescribing postoperative analgesics. Findings from this study might help clinicians improve maternal satisfaction and CS anesthesia care by designing anesthesia regimens that most closely meet the individual patient’s needs and expectations.

Our findings emphasize the importance to patients of superior intra- and postoperative analgesia. Limiting the dose of bupivacaine in subarachnoid block as part of a "single-shot" technique for CS has been advocated with the goals of reducing the incidence of maternal hypotension, decreasing nausea, reducing time to discharge from the postanesthesia care unit, and improving maternal satisfaction (16–18). However, smaller intrathecal bupivacaine doses are also associated with intraoperative pain and late anesthetic failures (16,17). Whereas nausea and vomiting still ranked relatively high among our patients’ concerns, pruritus and shivering caused only moderate concern. This information should be used to guide anesthetic choices, such as including spinal opioids in adequate doses to improve perioperative and postoperative analgesia despite a potential increase of pruritus and nausea.

	Appendix 1

Top Abstract Introduction Methods Results Discussion Appendix 1 Appendix 2 References

 
Priority Ranking and Relative Value Scales to Determine Preferences for Specific Anesthesia Outcomes and Potential Side Effects

We want to determine your preferences for each of the following possible outcomes of anesthesia care (i.e., which ones you think are better or worse than the others). Please carefully read each of the following descriptions of outcomes you could experience as a result of your anesthesia and surgery. Assume that each situation described is equally likely and that each condition will last an equal length of time. First, rank each of these outcomes (you could experience any of these) in relation to each other from 1 to 10 from the most desirable (1) to the least desirable (10). Next, pretend that you are given $100 in order to prevent the following undesirable outcomes of anesthesia. Distribute the $100 such that the more money you spend on a condition, the less likely that it will occur. Thus, you should spend more money on outcomes you most want to avoid. Important: You must spend all of your $100 (and no more than that). You can choose to allocate $0 to only one of the outcomes described. Please note that many of these outcomes have been made to sound extreme to help you decide your priorities. Most people do not in fact usually experience multiple significant side effects with anesthesia. Treatment for pain or side effects is always available.

	Appendix 2

Top Abstract Introduction Methods Results Discussion Appendix 1 Appendix 2 References

When providing pain relief, anesthesia doctors may need to make treatment decisions that "trade off" relieving pain during and after cesarean delivery with a possible increased risk of side effects. Look at the table below and choose the pain medication dose (smallest, moderate, or largest) that best describes your preference for pain relief balanced with the possible risk of side effects during and after your surgery and anesthesia. This information will not be used to select the medication used in your current anesthetic. Select the desired PAIN MEDICATION DOSE: Smallest/Moderate/Largest (please circle).

	Footnotes

 
This study was conducted at Lucile Packard Children’s Hospital and Stanford University School of Medicine, Stanford, CA.

Accepted for publication March 29, 2005.

This study was funded internally by the Department of Anesthesia, Stanford University School of Medicine. The authors involved in this study received no external support.

	References

Top Abstract Introduction Methods Results Discussion Appendix 1 Appendix 2 References

 

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Anesthesia & Analgesia® is published for the International Anesthesia Research Society® by Lippincott Williams & Wilkins with the assistance of Stanford University Libraries' HighWire Press®. Copyright 2006 by the International Anesthesia Research Society. Online ISSN: 1526-7598   Print ISSN: 0003-2999