Pain, nausea and vomiting are frequently listed by patients as their most important perioperative concerns. With the change in emphasis from an inpatient to outpatient hospital and office-based medical/surgical environment, there has been increased interest in the ‘big little problem’ of postoperative nausea and vomiting (PONV). Currently, the overall incidence of PONV is estimated to be 25 to 30%, with severe, intractable PONV estimated to occur in approximately 0.18% of all patients undergoing surgery. PONV can lead to delayed postanaesthesia care unit (PACU) recovery room discharge and unanticipated hospital admission, thereby increasing medical costs. The aetiology and consequences of PONV are complex and multifactorial, with patient-, medical- and surgery-related factors. A thorough understanding of these factors, as well as the neuropharmacology of multiple emetic receptors [dopaminergic, muscarinic, cholinergic, opioid, histamine, serotonin (5-hydroxy-tryptamine; 5-HT)] and physiology [cranial nerves VIII (acoustic-vestibular), IX (glossopharyngeal) and X (vagus), gastrointestinal reflex] relating to PONV are necessary to most effectively manage PONV. Commonly used older, traditional antiemetics for PONV include the anticholinergics (scopolamine), phenothiazines (promethazine), antihistamines (diphenhydramine), butyrophenones (droperidol) and benzamides (metoclopramide). These antiemetics have adverse effects such as dry mouth, sedation, hypotension, extrapyramidal symptoms, dystonic effects and restlessness. The newest class of antiemetics used for the prevention and treatment of PONV are the serotonin receptor antagonists (ondansetron, granisetron, tropisetron, dolasetron). These antiemetics do not have the adverse effects of the older, traditional antiemetics. Headache and dizziness are the main adverse effects of the serotonin receptor antagonists in the dosages used for PONV. The serotonin receptor antagonists have improved antiemetic effectiveness but are not as completely efficacious for PONV as they are for chemotherapy-induced nausea and vomiting. Older, traditional antiemetics (such as droperidol) compare favourably with the serotonin receptor antagonists regarding efficacy for PONV prevention. Combination antiemetic therapy improves efficacy for PONV prevention and treatment. In the difficult-to-treat PONV patient (as in the chemotherapy patient), suppression of numerous emetogenic peripheral stimuli and central neuroemetic receptors may be necessary. This multimodal PONV management approach includes use of: (i) multiple different antiemetic medications (double or triple combination antiemetic therapy acting at different neuroreceptor sites); (ii) less emetogenic anaesthesia techniques; (iii) adequate intravenous hydration; and (iv) adequate pain control.

Prevention and Treatment of Postoperative Nausea and Vomiting

<zdoi;10.1097/ALN.0000000000000935> Anesthesiology, V 124 • No 2 270 February 2016 P RACTICE guidelines are systematically developed recommendations that assist the practitioner and patient in making decisions about health care. These recommendations may be adopted, modified, or rejected according to the clinical needs and constraints and are not intended to replace local institutional policies. In addition, practice guidelines developed by the American Society of Anesthesiologists (ASA) are not intended as standards or absolute requirements, and their use cannot guarantee any specific outcome. Practice guidelines are subject to revision as warranted by the evolution of medical knowledge, technology, and practice. They provide basic recommendations that are supported by a synthesis and analysis of the current literature, expert and practitioner opinion, open-forum commentary, and clinical feasibility data. This document updates the “Practice Guidelines for Obstetric Anesthesia: An Updated Report by the ASA Task Force on Obstetric Anesthesia,” adopted by ASA in 2006 and published in 2007.†

Practice Guidelines for Obstetric Anesthesia: An Updated Report by the American Society of Anesthesiologists Task Force on Obstetric Anesthesia and the Society for Obstetric Anesthesia and Perinatology ∗

Unintended effects of epidural analgesia during labor: a systematic review.

The effectiveness of two epidural analgesic regimens on the ability to ambulate was compared in women in labor by a prospective, randomized, double-blind design. One group of patients received epidural fentanyl, a 75-micrograms bolus and an infusion of fentanyl 2.5 micrograms/mL at 15 mL/h (FENT, n = 53). A second group received ultra low-dose bupivacaine (0.04%), epinephrine (1.7 micrograms/mL), and fentanyl (1.7 micrograms/mL) (BEF, n = 77), a 15-mL bolus followed by an infusion at 15 mL/h. Adequate analgesia was rapidly obtained in 90.6% of patients in the FENT group and 92.2% of patients in the BEF group (P = 0.89). Seventy percent of patients in the FENT group ambulated versus 68% in the other group. The BEF mixture provided analgesia of longer duration (287 +/- 171 min versus 156 +/- 72 min, P = 0.0001). The number of patients delivering during administration of only their study drug (without needing higher doses of local anesthetics) was 52% for BEF and 21% for FENT (P = 0.0005). Hip flexion weakness precluding ambulation occurred in 17% (P = 0.002) of BEF patients and orthostatic hypotension in 9% (P = 0.08). Neither problem occurred in FENT patients. Neonatal outcome was similar in both groups. Approximately 70% of women receiving epidural analgesia with fentanyl or ultra low-dose bupivacaine, epinephrine, and fentanyl may ambulate safely during labor.

Epidural anesthesia for labor in an ambulatory patient

ANESTHESIA has become remarkably safe, and while death and permanent damage have become rare occurrences, other sequelae of anesthesia are gaining more importance. Postoperative nausea and vomiting (PONV) still is the most troublesome adverse event encountered in the recovery room, despite advances in prevention and treatment. The incidence of PONV has remained high and has a major negative impact on patient satisfaction about the overall surgical experience. Furthermore, the ongoing trend toward ambulatory procedures has increased the focus on PONV as its occurrence may delay discharge or cause unanticipated hospital admission. General anesthesia has long been considered as causing a greater frequency and severity of PONV than regional anesthetic techniques. Recent studies investigating this time-honored dictum in a controlled manner mostly, but not unanimously, confirmed it. Accordingly, considerable effort has been invested to examine etiology, define patients at risk, and outline preventive and therapeutic strategies in patients undergoing general anesthesia. Reviews dealing with PONV have discussed almost exclusively general anesthesia and largely ignored regional anesthesia. This contrasts with the increasing popularity of regional anesthesia. A survey in Europe showed that one third of patients are undergoing regional anesthesia for their operative procedure. In France, the proportion of regional anesthesia increased from 15 to 25% of all anesthetics administered from 1980 to 1996. The number of local anesthetic and analgesic agents available for regional anesthesia has increased over the last two decades. Since the introduction of intrathecal and epidural morphine in 1979, a multitude of medications, such as synthetic opioids, 2-agonists, and cholinesterase inhibitors, have been introduced in an attempt to enhance the action of local anesthetics. The decision about their usefulness will not only rely on their effects on nerve blockade and pain relief, but also on their influence on side effects such as PONV. This review focuses on PONV in the setting of perioperative regional anesthesia. General aspects of PONV, such as physiology, patient, and perioperative factors involved are discussed. Few studies regarding these issues have been specifically devoted to regional anesthesia. Therefore, much information must be derived from investigations of general anesthesia. Specific regional anesthetic techniques and the influence of adjunctive medications on PONV are also presented. Combined general–regional anesthesia is purposefully excluded, avoiding the many variables introduced by general anesthesia. A final section is devoted to continuous peripheral nerve blocks and their possible impact on PONV.

Postoperative nausea and vomiting in regional anesthesia: a review.

The analgesic efficacy of the continuous epidural infusion of 0.0625% bupivacaine/0.0002% fentanyl was compared with the infusion of 0.125% bupivacaine alone in a randomized, double-blind study of nulliparous women. Each patient received, in sequence: 1)3 ml of 0.5% bupivacaine with 1:200,000 epinep

Continuous Infusion Epidural Analgesia during Labor: A Randomized, Double-blind Comparison of 0.0625% Bupivacaine / 0.0002% Fentanyl Versus 0.125% Bupivacaine

A randomized, double blind, placebo-controlled study was performed to evaluate the analgesic efficacy and influence of continuing an epidural infusion of 0.125% bupivacaine beyond a cervical dilatation of 8 cm in nulliparous women. When the cervix was greater than or equal to 8 cm dilated, coded study solution was substituted for the known 0.125% bupivacaine solution. The study solution for 46 patients was 0.125% bupivacaine; 46 patients received saline. During the first stage of labor, 44 (96%) women in the bupivacaine group, and 45 (98%) in the saline group, had analgesia of excellent or good quality. During the second stage, 36 (82%) women in the bupivacaine group, versus 18 (41%) women in the saline group, had analgesia of excellent or good quality (P less than .0001). Six (13%) women in each group underwent cesarean delivery after the start of the study solution. Among the women who delivered vaginally, the mean (+/- S.D.) duration of the second stage of labor was 124 (+/- 70) min in the bupivacaine group, versus 94 (+/- 54) min in the saline group (P less than .05). Twenty-one of 40 (53%) women in the bupivacaine group, versus 11 of 40 (28%) in the saline group, underwent instrumental vaginal delivery (P less than .05). Twenty-eight of 40 (70%) women in the bupivacaine group, versus six of 40 (15%) in the saline group; had surgical perineal anesthesia for vaginal delivery (P less than .0001). There were no significant differences between groups in Apgar scores or umbilical cord blood acid-base values.(ABSTRACT TRUNCATED AT 250 WORDS)

The influence of continuous epidural bupivacaine analgesia on the second stage of labor and method of delivery in nulliparous women

The analgesic efficacy of the continuous epidural infusion of 0.0625% bupivacaine/0.0002% fentanyl was compared with the infusion of 0.125% bupivacaine alone in a randomized, double-blind study of nulliparous women. Each patient received, in sequence: 1)3 ml of 0.5% bupivacaine with 1:200,000 epinephrine; 2) 6 ml of study solution 1 (bupivacaine-fentanyl group: 0.125% bupivacaine/ 0.0008% fentanyl; bupivacaine-only group: 0.25% bupivacaine alone); and 3) a continuous epidural in fusion of study solution 2 at a rate of 12.5 ml/h (bupivacaine-fentanyl group: 0.0625% bupivacaine/0.0002% fentanyl; bupivacaine-only group: 0.125% bupivacaine alone). The epidural infusion was discontinued at full cervical dilatation, but patients who lacked perineal anesthesia received one or two 5-ml boluses of study solution 3 (bupivacaine-fentanyl group: 0.0625% bupivacaine alone; bupivacaine-only group: 0.125% bupivacaine alone). During the first stage of labor, 36 of 41 (88%) women in the bupivacaine-fentanyl group, and 37 of 39 (95%) women in the bupivacaine-only group, had analgesia of excellent or good quality (P = NS). During the second stage, 22 of 37 (59%) women in the bupivacaine-fentanyl group, and 23 of 35 (66%) women in the bupivacaine-only group, rated their analgesia as excellent or good (P = NS). Women in the bupivacaine-only group were more likely to have motor block at full cervical dilatation (P <.001). There was no significant difference between groups in duration of the second stage of labor, duration of pushing, position of the vertex before delivery, method of delivery, Apgar scores, or umbilical cord blood gas and acid-base values. The authors conclude that the continuous epidural infusion of 0.0625% bupivacaine/0.0002% fentanyl produced analgesia similar to that provided by the infusion of 0.125% bupivacaine alone. However, the less intense motor block experienced by women in the bupivacaine-fentanyl group did not significantly shorten the second stage or result in a greater frequency of spontaneous delivery.

Continuous Infusion Epidural Analgesia during Labor: A Randomized, Double-blind Comparison of 0.0625% Bupivacaine/0.0002% Fentanyl Versus 0.125% Bupivacaine

Cindy L. Owen

Papers

Continuous Infusion Epidural Analgesia during Labor: A Randomized, Double-blind Comparison of 0.0625% Bupivacaine / 0.0002% Fentanyl Versus 0.125% Bupivacaine

The influence of continuous epidural bupivacaine analgesia on the second stage of labor and method of delivery in nulliparous women

Continuous Infusion Epidural Analgesia during Labor: A Randomized, Double-blind Comparison of 0.0625% Bupivacaine/0.0002% Fentanyl Versus 0.125% Bupivacaine

Administration of metoclopramide for prevention of nausea and vomiting during epidural anesthesia for elective cesarean section.

Administration of Metoclopramide for Prevention of Nausea and Vomiting During Epidural Anesthesia for Elective Cesarean Section