Interventions for preventing nausea and vomiting in women undergoing regional anaesthesia for caesarean section

Epidural ropivacaine versus bupivacaine for cesarean sections: a system review and meta-analysis

INTRODUCTION

It is still no consensus on the use of ropivacaine or bupivacaine in epidural anesthesia for cesarean section (CS), because their anesthetic potency and relative complications remains controversial. This system review and meta-analysis aimed to compare the efficacy of epidural ropivacaine and bupivacaine for elective CSs and investigate relative complications for parturients and neonates.

METHODS

We searched PubMed, MEDLINE, Embase, Cochrane Library, Science-Direct, and Google Scholar to June 30, 2023 for randomized controlled trials (RCTs), which compared epidural ropivacaine with bupivacaine for elective CSs. The success rate of epidural anesthesia (EA) was primary outcome. The secondary outcomes included onset times of sensory block, maternal side effects, neonatal Apgar scores and umbilical artery pH.

RESULTS

We analyzed 8 RCTs with 532 parturients. 0.75% ropivacaine is associated with a shorter onset time of sensory block than 0.5% bupivacaine (SMD = -0.43, 95% CI: -0.70 to -0.17; p = .001). 0.5% ropivacaine resulted in a reduced nausea than 0.5% bupivacaine (RR = 0.49, 95% CI: 0.28 to 0.83; p = .008). In addition, there were no significant difference between ropivacaine and bupivacaine groups in terms of success rate of epidural anesthesia, maternal side effects (hypotension, bradycardia, shivering), and neonatal Apgar scores and umbilical artery pH.

CONCLUSIONS

The findings suggest that there were no significant difference between epidural ropivacaine and bupivacaine for elective CSs in terms of the success rate (85.9% vs. 83.5), maternal side effects (hypotension, bradycardia, shivering), and neonatal Apgar scores and umbilical artery pH. But compared with 0.5% bupivacaine, epidural 0.75% ropivacaine was mildly effective for reducing onset time of sensory block and 0.5% ropivacaine reduced the incidence of maternal nausea.

Which 5-HT3 antagonist prevents nausea and vomiting in cesarean section more effectively: a network meta-analysis

INTRODUCTION

Selective 5-hydroxytryptamine 3 receptor (5-HT3) antagonists are commonly used to prevent nausea and vomiting (NV) after cesarean section, but the comparative efficacy of different 5-HT3 antagonists remains unclear. This network meta-analysis aimed to determine which 5-HT3 antagonists might be the preferred choice for preventing NV in parturient scheduled for elective cesarean delivery under spinal anesthesia.

EVIDENCE ACQUISITION

PubMed, EMBASE, Cochrane library, and Web of Science were searched for relevant randomized controlled trials (RCTs) published before August 24, 2023. Random network meta-analysis was performed using Stata 14.0 to estimate the efficacy of different 5-HT3 antagonists in preventing intra- and post-operative NV.

EVIDENCE SYNTHESIS

Twenty-eight studies involving seven dosing regimens of three 5-HT3 antagonists were included. Pooled results showed that ondansetron 12 mg was superior to other six dosing regimens in the prevention of postoperative NV (PONV), PON, and POV, with the ranking probability of 80.2%, 95.8%, and 87.7%, respectively, followed by granisetron two mg. Ondansetron 4 mg might be the first choice for preventing intraoperative NV (IONV) (92.8%), with the least use of postoperative rescue antiemetics (90.6%). Granisetron 3 mg and tropisetron 2 mg might be the best options for preventing ION and IOV, respectively.

CONCLUSIONS

Based on available data, ondansetron 12 mg may have the best efficacy in preventing PONV, PON, and POV. Additionally, more studies are warranted to compare the safety of ondansetron 12 mg versus granisetron two mg.

Comparative Efficacy of Different Classes of Antiemetic Medications for the Prevention of Nausea and Vomiting in Cesarean Section: A Network Meta-Analysis

Background

Antiemetic medications have been associated with the prevention of nausea and vomiting in cesarean section, although less is known about the comparative efficacy of different medication classes.

Methods

We conducted a systematic review with network meta-analyses to compare and rank antiemetic medication classes (5-HT3 receptor antagonists, dopamine receptor antagonists, corticosteroids, antihistamines, anticholinergic agents, sedatives, and opioid antagonists or partial agonists) in terms of preventing intra- and postoperative nausea and vomiting among patients undergoing cesarean section. We included all randomized controlled trials (RCTs) that evaluated any antiemetic medication classes' treatment for target outcomes. Network meta-analysis was conducted with a frequentist approach using the R netmeta package. A total of 58 trials were included (6,665 women undergoing cesarean section; mean age, 28.1 years). Results: Compared with placebo, all interventions reduced the odds of intraoperative nausea (except antihistamines), intraoperative vomiting (except antihistamines), postoperative nausea (except anticholinergic agents and opioid antagonists), and postoperative vomiting (except opioid antagonists). In terms of intraoperative nausea and both intra- and postoperative vomiting, sedatives ranked first among other medication classes.

Conclusions

The relative effect sizes for various classes of antiemetic medication in preventing nausea and vomiting in the cesarean section were modeled using the principles of network meta-analysis which may facilitate informed clinical decision-making.

Metoclopramide and Propofol to Prevent Nausea and Vomiting during Cesarean Section under Spinal Anesthesia: A Randomized, Placebo-Controlled, Double-Blind Trial

BACKGROUND

Intra-operative nausea, vomiting and retching (NVR) are frequently associated with subarachnoid anesthesia (SA) in women undergoing cesarean section (CS). In this study performed in women undergoing CS under SA with a risk factor control strategy, we compared saline (placebo), propofol, metoclopramide and both drugs to prevent NVR.

METHODS

We recorded NVR events in 110 women undergoing CS who were randomized after umbilical cord clamping to receive saline (S; n = 27), metoclopramide 10 mg (M; n = 28), propofol 1 mg/kg/h (P; n = 27) or both drugs (PM; n = 28).

RESULTS

The proportion of women with intra-operative nausea was: S: 17/27 (63%); P: 15/27 (56%); M: 13/28 (46%); PM: 6/28 (21%) (p = 0.012, Cramér's V = 0.31 (large effect). The proportion of women with intra-operative vomiting/retching was: S: 9/27 (33%); M: 7/27 (25%); P: 3/28 (11%); PM 2/28 (7%) (p = 0.049, Cramér's V = 0.26 (medium effect). Post-hoc multiple comparisons revealed a significant reduction in NVR episodes and NRS scores between the PM group and control. Sedation scores did not differ among groups.

CONCLUSION

In women undergoing CS under SA with a risk factor control strategy, combined propofol and metoclopramide reduce nausea and vomiting.

Magnitude and associated factors of intraoperative nausea and vomiting among parturients who gave birth with cesarean section under spinal anesthesia at South Gondar zone Hospitals, Ethiopia

BACKGROUND

Intraoperative nausea and vomiting are common intraoperative events by which parturient feel discomfort and disturbed after spinal anesthesia.

METHODS

Hospital-based cross-sectional study was conducted on mothers who underwent cesarean section with spinal anesthesia. Descriptive analysis and chi-square test were employed. Bivariable and multivariable logistic regressions were used to measure the association of factors with the outcome variable intraoperative nausea and vomiting. A p-value of ≤0.05 was used to decide statistical significance for multivariable logistic regression.

RESULT

A total of 246 parturients were participated in this study. The incidence of intraoperative nausea and vomiting was 40.2%. According to multivariable logistic regression, age greater than 30 years (AOR, 6.26; 95%CI, 2.2-17.78; p-value 0.001), primiparous (AOR, 3.72; 95%CI, 1.35-10.24; p-value, 0.011), having motion sickness (AOR, 7.1; 95%CI, 2.75-18.33; p-value 0.001), emergency cesarean sectin (AOR, 9.85; 95%CI, 3.19-30.38; p-value 0.001), oxygen suplimentation (AOR, 0.021; 95%CI, 0.005-0.08; p-value 0.0001) and uterotonic agent (AOR, 2.99; 95%CI 1.24-7.22; p-value 0.015) had statistically significant association with intraoperative nausea and vomiting.

CONCLUSION

In our study, the overall incidence of intraoperative nausea and vomiting after spinal anesthesia was 40.2%. Parturients with age greater than 30 years, having motion sickness, didn't get intraoperative supplemental oxygen, oxytocin used for the uterotonic purpose, emergency surgery, and primiparous were at increased risk of intraoperative nausea and vomiting.

Interventions for preventing nausea and vomiting in women undergoing regional anaesthesia for caesarean section

BACKGROUND

Nausea and vomiting are distressing symptoms which are experienced commonly during caesarean section under regional anaesthesia and in the postoperative period.  OBJECTIVES: To assess the efficacy of pharmacological and non-pharmacological interventions versus placebo or no intervention given prophylactically to prevent nausea and vomiting in women undergoing regional anaesthesia for caesarean section.

SEARCH METHODS

For this update, we searched Cochrane Pregnancy and Childbirth's Trials Register, ClinicalTrials.gov and the WHO International Clinical Trials Registry Platform (ICTRP) (16 April 2020), and reference lists of retrieved studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of studies and conference abstracts, and excluded quasi-RCTs and cross-over studies.

DATA COLLECTION AND ANALYSIS

Review authors independently assessed the studies for inclusion, assessed risk of bias and carried out data extraction. Our primary outcomes are intraoperative and postoperative nausea and vomiting. Data entry was checked. Two review authors independently assessed the certainty of the evidence using the GRADE approach.

MAIN RESULTS

Eighty-four studies (involving 10,990 women) met our inclusion criteria. Sixty-nine studies, involving 8928 women, contributed data. Most studies involved women undergoing elective caesarean section. Many studies were small with unclear risk of bias and sometimes few events. The overall certainty of the evidence assessed using GRADE was moderate to very low. 5-HT3 antagonists: We found intraoperative nausea may be reduced by 5-HT3 antagonists (average risk ratio (aRR) 0.55, 95% confidence interval (CI) 0.42 to 0.71, 12 studies, 1419 women, low-certainty evidence). There may be a reduction in intraoperative vomiting but the evidence is very uncertain (aRR 0.46, 95% CI 0.29 to 0.73, 11 studies, 1414 women, very low-certainty evidence). There is probably a reduction in postoperative nausea (aRR 0.40, 95% CI 0.30 to 0.54, 10 studies, 1340 women, moderate-certainty evidence), and these drugs may show a reduction in postoperative vomiting (aRR 0.47, 95% CI 0.31 to 0.69, 10 studies, 1450 women, low-certainty evidence). Dopamine antagonists: We found dopamine antagonists may reduce intraoperative nausea but the evidence is very uncertain (aRR 0.38, 95% CI 0.27 to 0.52, 15 studies, 1180 women, very low-certainty evidence). Dopamine antagonists may reduce intraoperative vomiting (aRR 0.41, 95% CI 0.28 to 0.60, 12 studies, 942 women, low-certainty evidence) and postoperative nausea (aRR 0.61, 95% CI 0.48 to 0.79, 7 studies, 601 women, low-certainty evidence). We are uncertain if dopamine antagonists reduce postoperative vomiting (aRR 0.63, 95% CI 0.44 to 0.92, 9 studies, 860 women, very low-certainty evidence). Corticosteroids (steroids): We are uncertain if intraoperative nausea is reduced by corticosteroids (aRR 0.56, 95% CI 0.37 to 0.83, 6 studies, 609 women, very low-certainty evidence) similarly for intraoperative vomiting (aRR 0.52, 95% CI 0.31 to 0.87, 6 studies, 609 women, very low-certainty evidence). Corticosteroids probably reduce postoperative nausea (aRR 0.59, 95% CI 0.49 to 0.73, 6 studies, 733 women, moderate-certainty evidence), and may reduce postoperative vomiting (aRR 0.68, 95% CI 0.49 to 0.95, 7 studies, 793 women, low-certainty evidence). Antihistamines: Antihistamines may have little to no effect on intraoperative nausea (RR 0.99, 95% CI 0.47 to 2.11, 1 study, 149 women, very low-certainty evidence) or intraoperative vomiting (no events in the one study of 149 women). Antihistamines may reduce postoperative nausea (aRR 0.44, 95% CI 0.30 to 0.64, 4 studies, 514 women, low-certainty evidence), however, we are uncertain whether antihistamines reduce postoperative vomiting (average RR 0.48, 95% CI 0.29 to 0.81, 3 studies, 333 women, very low-certainty evidence). Anticholinergics: Anticholinergics may reduce intraoperative nausea (aRR 0.67, 95% CI 0.51 to 0.87, 4 studies, 453 women, low-certainty evidence) but may have little to no effect on intraoperative vomiting (aRR 0.79, 95% CI 0.40 to 1.54, 4 studies; 453 women, very low-certainty evidence). No studies looked at anticholinergics in postoperative nausea, but they may reduce postoperative vomiting (aRR 0.55, 95% CI 0.41 to 0.74, 1 study, 161 women, low-certainty evidence). Sedatives: We found that sedatives probably reduce intraoperative nausea (aRR 0.65, 95% CI 0.51 to 0.82, 8 studies, 593 women, moderate-certainty evidence) and intraoperative vomiting (aRR 0.35, 95% CI 0.24 to 0.52, 8 studies, 593 women, moderate-certainty evidence). However, we are uncertain whether sedatives reduce postoperative nausea (aRR 0.25, 95% CI 0.09 to 0.71, 2 studies, 145 women, very low-certainty evidence) and they may reduce postoperative vomiting (aRR 0.09, 95% CI 0.03 to 0.28, 2 studies, 145 women, low-certainty evidence). Opioid antagonists: There were no studies assessing intraoperative nausea or vomiting. Opioid antagonists may result in little or no difference to the number of women having postoperative nausea (aRR 0.75, 95% CI 0.39 to 1.45, 1 study, 120 women, low-certainty evidence) or postoperative vomiting (aRR 1.25, 95% CI 0.35 to 4.43, 1 study, 120 women, low-certainty evidence). Acupressure: It is uncertain whether acupressure/acupuncture reduces intraoperative nausea (aRR 0.55, 95% CI 0.41 to 0.74, 9 studies, 1221 women, very low-certainty evidence). Acupressure may reduce intraoperative vomiting (aRR 0.52, 95% CI 0.33 to 0.80, 9 studies, 1221 women, low-certainty evidence) but it is uncertain whether it reduces postoperative nausea (aRR 0.46, 95% CI 0.27 to 0.75, 7 studies, 1069 women, very low-certainty evidence) or postoperative vomiting (aRR 0.52, 95% CI 0.34 to 0.79, 7 studies, 1069 women, very low-certainty evidence). Ginger: It is uncertain whether ginger makes any difference to the number of women having intraoperative nausea (aRR 0.66, 95% CI 0.36 to 1.21, 2 studies, 331 women, very low-certainty evidence), intraoperative vomiting (aRR 0.62, 95% CI 0.38 to 1.00, 2 studies, 331 women, very low-certainty evidence), postoperative nausea (aRR 0.63, 95% CI 0.22 to 1.77, 1 study, 92 women, very low-certainty evidence) and postoperative vomiting (aRR 0.20, 95% CI 0.02 to 1.65, 1 study, 92 women, very low-certainty evidence). Few studies assessed our secondary outcomes including adverse effects or women's views.

AUTHORS' CONCLUSIONS

This review indicates that 5-HT3 antagonists, dopamine antagonists, corticosteroids, sedatives and acupressure probably or possibly have efficacy in reducing nausea and vomiting in women undergoing regional anaesthesia for caesarean section. However the certainty of evidence varied widely and was generally low. Future research is needed to assess side effects of treatment, women's views and to compare the efficacy of combinations of different medications.

Comparison of the prophylactic effect of dexamethasone and dexmedetomidine and their combination in reducing postoperative nausea and vomiting in patients undergoing laparoscopic cholecystectomy

Nausea and vomiting are some of the most common complaints of patients after any anesthesia, which is often associated with postoperative pain. The double-blind clinical trial study aimed to compare the prophylactic effect of dexamethasone and dexmedetomidine and their combination in reducing postoperative nausea and vomiting in patients undergoing laparoscopic cholecystectomy. One hundred sixty-two patients undergoing laparoscopic cholecystectomy were enrolled in the study. In the first group of patients, 25 mg of dexmedetomidine were administered slowly. In comparison, the patients in the second group received dexamethasone (4 ml/2 mg) with 0.1 mg/kg of normal saline solution. The third group received a combination of dexmedetomidine and dexamethasone. Hemodynamic changes were recorded during surgery and after surgery, and the patients were admitted to recovery. Nausea and vomiting scores were recorded 2 and 4 hours after surgery. Blood pressure and heart rate were lower in the dexmedetomidine group at all times (P<0.05). Two hours after surgery, the dexamethasone and dexmedetomidine combination group had less vomiting (P=0.012). The incidence of nausea 2 and 4 hours after surgery was lower in the dexamethasone and dexmedetomidine combination group (P<0.05). Blood pressure and heart rate were lower in the dexmedetomidine group at all times. The dexmedetomidine and dexamethasone combination decreased postoperative nausea and vomiting in patients. Therefore, we recommend using a dexmedetomidine and dexamethasone combination for reducing postoperative nausea and vomiting.

The Quality of Recovery after Dexamethasone, Ondansetron, or Placebo Administration in Patients Undergoing Lower Limbs Orthopedic Surgery under Spinal Anesthesia Using Intrathecal Morphine. A Randomized Controlled Trial

Intrathecal morphine is widely and successfully used to prevent postoperative pain after orthopedic surgery, but it is frequently associated with side effects. The aim of this study was to evaluate the effect of dexamethasone or ondansetron when compared to placebo to reduce the occurrence of these undesirable effects and, consequently, to improve the quality of recovery based on patient's perspective. Methods. One hundred and thirty-five patients undergoing lower extremity orthopedic surgery under spinal anesthesia using bupivacaine and morphine were randomly assigned to receive IV dexamethasone, ondansetron, or saline. On the morning following surgery, a quality of recovery questionnaire (QoR-40) was completed. Results. No differences were detected in the global and dimensional QoR-40 scores following surgery; however, following postanesthesia care unit (PACU) discharge, pain scores were higher in patients receiving ondansetron compared with patients who received dexamethasone. Conclusion. Neither ondansetron nor dexamethasone improves the quality of recovery after lower limbs orthopedic surgery under spinal anesthesia using intrathecal morphine.

The Advantage of Implementation of Enhanced Recovery After Surgery (ERAS) in Acute Pain Management During Elective Cesarean Delivery: A Prospective Randomized Controlled Trial

OBJECTIVE

The aim of this study was to test whether the implementation of an enhanced recovery after surgery (ERAS) protocol for patients undergoing elective cesarean delivery has a positive impact on the postoperative status of the patients in terms of pain management, hospital stay, hospitalization costs, and adverse reactions.

METHODS

Patients who underwent elective cesarean delivery were randomized into two groups - ERAS group and control group - and the groups were managed with the ERAS protocol and traditional protocol, respectively.

RESULTS

Compared to the control group, the ERAS group had significantly fewer patients with intraoperative nausea, pain of visual analog scale (VAS) scores, and VAS grade >3 during rest in the first 24 h and during motion in the first 24 and 48 h after surgery. There were no intergroup differences in the requirement of extra analgesics, the incidence of vomiting, shivering, hypotension, postoperative nausea, and pruritus. None of the patients in either group had postoperative vomiting. Patient satisfaction rated as per the VAS was significantly higher in the ERAS group than in the control group. The total length of stay, postoperative length of stay, and the cost of anesthesia in both groups were comparable. Further, the average daily hospitalization cost was significantly lower in the ERAS group than in the control group.

CONCLUSION

The ERAS protocol shows promise and appears to be worthwhile for widespread implementation among patients undergoing elective cesarean delivery; it was found to be beneficial in reducing the postoperative pain, incidence of intraoperative nausea, and average cost of hospitalization and also improved patient satisfaction.

Empirical comparison of univariate and multivariate meta-analyses in Cochrane Pregnancy and Childbirth reviews with multiple binary outcomes

BACKGROUND

Multivariate meta-analysis (MVMA) jointly synthesizes effects for multiple correlated outcomes. The MVMA model is potentially more difficult and time-consuming to apply than univariate models, so if its use makes little difference to parameter estimates, it could be argued that it is redundant.

METHODS

We assessed the applicability and impact of MVMA in Cochrane Pregnancy and Childbirth (CPCB) systematic reviews. We applied MVMA to CPCB reviews published between 2011 and 2013 with two or more binary outcomes with at least three studies and compared findings with results of univariate meta-analyses. Univariate random effects meta-analysis models were fitted using restricted maximum likelihood estimation (REML).

RESULTS

Eighty CPCB reviews were published. MVMA could not be applied in 70 of these reviews. MVMA was not feasible in three of the remaining 10 reviews because the appropriate models failed to converge. Estimates from MVMA agreed with those of univariate analyses in most of the other seven reviews. Statistical significance changed in two reviews: In one, this was due to a very small change in P value; in the other, the MVMA result for one outcome suggested that previous univariate results may be vulnerable to small-study effects and that the certainty of clinical conclusions needs consideration.

CONCLUSIONS

MVMA methods can be applied only in a minority of reviews of interventions in pregnancy and childbirth and can be difficult to apply because of missing correlations or lack of convergence. Nevertheless, clinical and/or statistical conclusions from MVMA may occasionally differ from those from univariate analyses.

Naturopathic Treatment and Complementary Medicine in Surgical Practice

BACKGROUND

Many patients in Germany use naturopathic treatments and complementary medicine. Surveys have shown that many also use them as a concomitant treatment to surgery.

METHODS

Multiple databases were systematically searched for systematic reviews, controlled trials, and experimental studies concerning the use of naturopathic treatments and complementary medicine in the management of typical post-operative problems (PROSPERO CRD42018095330).

RESULTS

Of the 387 publications identified by the search, 76 fulfilled the inclusion criteria. In patients with abnormal gastrointestinal activity, acupuncture can improve motility, ease the passing of flatus, and lead to earlier defecation. Acupuncture and acupressure can reduce postoperative nausea and vomiting, as well as pain. More-over,aromatherapy and music therapy seem to reduce pain, stress and anxiety and to improve sleep. Further studies are needed to determine whether phytotherapeutic treatments are effective for the improvement of gastrointestinal function or the reduction of stress. It also remains unclear whether surgical patients can benefit from the methods of mind body medicine.

CONCLUSION

Certain naturopathic treatments and complementary medical methods may be useful in postoperative care and deserve more intensive study. In the publications consulted for this review, no serious side effects were reported.

Effectiveness of P6 Stimulation for Reduction of Nausea and Vomiting During Caesarean Section Under Combined Spinal-Epidural Anaesthesia: A Randomised Controlled Trial

Objective

Obstetric patients who receive combined spinal-epidural (CSE) anaesthesia for elective caesarean section (CS) frequently experience intraoperative nausea and vomiting (N&V). Prophylactic therapy with antiemetic agents can have multiple adverse effects to the mother and baby. We designed a randomised clinical trial to evaluate the efficacy of electrical P6 stimulation for prophylactic N&V treatment for scheduled elective CS performed under CSE anaesthesia.

Methods

Following the Institutional Review Board approval and informed consent, a total of 180 patients were randomly allocated into three groups: (1) P6 stimulation (via a peripheral nerve stimulator), (2) intravenous (IV) antiemetics (metoclopramide and ondansetron), and (3) control (no IV antiemetic medications and no P6 stimulation), with 60 parturients in each group.

Results

Significantly fewer patients experienced intraoperative N&V in the P6 group (nausea 36.7% and vomiting 13.3%) and IV antiemetic group (nausea 23.3% and vomiting 16.7%) than those in the control group (nausea 73.3% and vomiting 45%; p<0.001). In addition, significantly fewer patients required rescue antiemetic medications in the P6 group (35%) and the IV antiemetic group (31.7%) than those in the control group (73.3%; p<0.001). There was no significant difference in the overall anaesthetic care satisfaction reported between the three study groups.

Conclusion

Our data suggest that P6 stimulation is as simple and as effective as our routine prophylactic IV antiemetic treatment for prevention of N&V during CS performed under CSE anaesthesia that could be of great interest to patients and obstetric anaesthesiologists who prefer treatments with fewer potential side effects.

Use of propofol for prevention of post-delivery nausea during cesarean section: a double-blind, randomized, placebo-controlled trial

PURPOSE

Nausea and vomiting are common, undesirable symptoms during cesarean section. We conducted this study to assess the antiemetic properties of propofol for the prevention and immediate treatment of post-delivery nausea and vomiting during cesarean section under combined spinal-epidural anesthesia.

METHODS

Eighty women undergoing elective cesarean delivery under combined spinal-epidural anesthesia were randomized to receive either propofol at a plasma concentration of 1000 ng/mL or normal saline immediately after clamping of the umbilical cord. The incidence of post-delivery nausea and vomiting, patients requiring rescue antiemetic, bispectral index, sedation score, and the incidence of hypotension were assessed intraoperatively. Satisfaction and neonatal behavioral neurological assessments were evaluated postoperatively.

RESULTS

The incidence of nausea was significantly lower in the propofol group compared to the placebo group (25% versus 60%, P < 0.001). The incidence of retching and vomiting showed no significant difference between the two groups. Propofol 20 mg as a rescue antiemetic was significantly effective in both the groups. Satisfaction level of patients and obstetricians in the propofol group was higher than in the placebo group. There was no statistical difference in the incidence of hypotension between the two groups both pre- and post-delivery. There was no difference in postoperative neonatal behavioral neurological assessment between groups.

CONCLUSION

Propofol at a plasma concentration of 1000 ng/mL significantly reduced the incidence of post-delivery nausea compared to placebo, but had no effect on reducing retching or vomiting episodes during cesarean section.

The Effect of Different Doses of Intrathecal Hyperbaric Bupivacaine Plus Sufentanil in Spinal Anesthesia for Cesarean Sections

Background

Decreasing side effects and improving the quality of block in caesarean sections by appropriate dosage of local anesthetics and adjuvants could play an important role in the safe management of cesarean section. The present study aimed at comparing the effects of 3 different doses of intrathecal hyperbaric bupivacaine injected with a fixed dose of sufentanil in cesarean sections.

Methods

In a double- blind randomized clinical trial, 105 candidates of elective cesarean section were randomly assigned into 3 groups of 8, 9, and 10 mg of intrathecal bupivacaine plus sufentanil 2.5 µg. The maximum level of sensory block, the intensity of motor block, and vital signs were measured at regular intervals. The incidence of hypotension and bradycardia were also recorded.

Results

No significant difference was found between the maximum level of sensory block and the intensity of motor block in 3 groups. The incidences of hypotension and bradycardia as well as administration of atropine and ephedrine were comparable among the 3 groups (P > 0.05).

Conclusions

According to similar effects of different doses of bupivacaine, administration of lower doses of bupivacaine (8mg) is more reasonable for spinal anesthesia for cesarean section.

Preventing nausea and vomiting in women undergoing regional anesthesia for cesarean section: challenges and solutions

BACKGROUND

Intraoperative nausea and vomiting (IONV) or postoperative nausea and vomiting (PONV) affecting women undergoing regional anesthesia for cesarean section is an important clinical problem since these techniques are used widely. There are burdens of literature about IONV/PONV and several in parturient and cesarean. However, it needs more attention. The underlying mechanisms of IONV and PONV in the obstetrical setting mainly include hypotension due to sympathicolysis during neuraxial anesthesia, bradycardia owing to an increased vagal tone, the visceral stimulation via the surgical procedure and intravenously administered opioids.

METHODS

Given the high and even increasing rate of cesarean sections and the sparse information on the etiology, incidence and severity of nausea and vomiting and the impact of prophylactic measures on the incidence of PONV/IONV, this article aims to review the available information and provide pragmatic suggestions on how to prevent nausea and vomiting in this patient cohort. Current literature and guidelines were identified by electronic database searching (MEDLINE via PubMed and Cochrane database of systematic reviews) up to present, searching through reference lists of included literature and personal contact with experts.

DISCUSSION AND CONCLUSION

Taking into account the current guidelines and literature as well as everyday clinical experience, the first step for decreasing the incidence of IONV and PONV is a comprehensive management of circulatory parameters. This management includes liberal perioperative fluid administration and the application of vasopressors as the circumstances require. By using low-dose local anesthetics, an additional application of intrathecal or spinal opioids or hyperbaric solutions for a sufficient controllability of neuraxial distribution, maternal hypotension might be reduced. Performing a combined spinal-epidural anesthesia or epidural anesthesia may be considered as an alternative to spinal anesthesia. Antiemetic drugs may be administered restrainedly due to off-label use in pregnant women for IONV or PONV prophylaxis and may be reserved for treatment.

A low dose of droperidol decreases the desflurane concentration needed during breast cancer surgery: a randomized double-blinded study

BACKGROUND

Droperidol (DHB) reportedly reduces the dose of propofol needed to achieve hypnosis when anesthesia is induced and decreases the bispectral index (BIS) in propofol-sedated patients during spinal anesthesia. We reported previously that supplemental DHB decreased the BIS after the administration of sevoflurane and remifentanil. This study investigated the effect of DHB on desflurane (DES) consumption in a clinical setting.

METHODS

We conducted a prospective, randomized double-blinded study of 35 women with American Society of Anesthesiologist physical status I or II who underwent a mastectomy. Either DHB (20 µg/kg) or a saline placebo was administered to patients 30 min after the induction of anesthesia. A blinded anesthesiologist maintained a BIS value of 50 during anesthesia by modulating inhaled DES concentrations that changed 0.5% at 2.5 min intervals and maintained analgesia via the constant administration of remifentanil by referring to vital signs. The primary endpoint was the effect of DHB on DES consumption. The secondary endpoints included blood circulatory parameters, the time from the end of surgery to extubation, and discharge time between the groups.

RESULTS

The characteristics of the patients did not differ between the groups. The DHB group used a mean of 27.2 ± 6.0 ml of DES compared with 41.4 ± 9.5 ml by the placebo group (P < 0.05).

CONCLUSIONS

A small dose of DHB reduced the DES concentration needed to maintain a BIS of 50. Our results show that DHB reduced the consumption of DES without adverse effects.

A comparative study of effects of glycopyrrolate and ondansetron on nausea and vomiting in cesarean section under spinal anesthesia

BACKGROUND AND AIM

Nausea and vomiting causes distress to patients and increases surgical complications. Though various antiemetics are available, their effectiveness and fetal safety profile when used in parturient remains debatable. This randomized, double-blind, comparative study was designed with an aim to compare the antiemetic effects of ondansetron and glycopyrrolate during cesarean section.

METHODS

Sixty-six parturients (American Society of Anesthesiologist physical status I-II) scheduled for elective cesarean section were randomized to receive intravenous ondansetron 4 mg (Group O, n = 32) or glycopyrrolate 0.2 mg (Group G, n = 31) before spinal anesthesia. Outcome measures studied were emesis, episodes of hypotension and bradycardia and pain, till 10 h postoperative. Statistical software used was Epi Info 7 and Microsoft Excel.

RESULTS

There was no significant difference in nausea and vomiting at all the study intervals between the two groups statistically. There was no difference in episodes of hypotension, but episodes of bradycardia were significantly less in glycopyrrolate group (26%) than in ondansetron group (56%) (P = 0.027). There was no difference in additional analgesic requirements. However, the incidence of dry mouth was significantly greater in glycopyrrolate group (21 [68%]) as compared to ondansetron group (5 [16%]) (P = 0.00).

CONCLUSION

Effect of glycopyrrolate on nausea and vomiting during cesarean section are comparable to ondansetron, but with an increased incidence of dry mouth. Glycopyrrolate has no effect on hypotension or additional analgesic requirements, but the incidence of bradycardia is significantly less.

Prevention of postoperative nausea and vomiting with a subhypnotic dose of Propofol in patients undergoing lower abdominal surgery: A prospective, randomized, double-blind study

Background:

Postoperative nausea and vomiting (PONV) is a common complication after general anesthesia in patients undergoing elective lower abdominal surgery. We aimed to compare the effect of a sub hypnotic dose of Propofol in the prevention of PONV after lower abdominal surgery with that of the conventional antiemetic drug Metoclopramide.

Materials and Methods:

In this prospective, randomized, double-blind, placebo-controlled study, 104 patients with American Society of Anesthesiologists (ASA) class I or II status, aged 18–65 years, and undergoing elective lower abdominal surgery were randomized to one of four groups (n = 26 each). The patients in the four groups were administered intravenously Propofol 20 mg (G1), Propofol 30 mg (G2), Metoclopramide 10 mg (G3), and placebo (G4), 15 min before skin closure. All episodes of PONV during the first 24 h after anesthesia were recorded by an investigator who was blinded to treatment assignment.

Results:

There were no significant differences between the treatment groups with regard to their gender, age, ASA class, duration of surgery, duration of recovery time and hospital stay, and also body mass index (BMI) (P > 0.05). The prevalence of PONV 0-6 h after anesthesia was 23.08% with Propofol 20 mg (P = 0.005), 15.38% with Propofol 30 mg (P = 0.016), 15.38% with Metoclopramide 10 mg (P = 0.016), compared to 30.77% with placebo (P = 0.005).

Conclusions:

Administration of a subhypnotic dose of Propofol (30 mg) was found to be as effective as 10 mg Metoclopramide in reducing the incidence and severity of PONV in adult patients undergoing elective lower abdominal surgeries under Isoflurane-based anesthesia in the early postoperative period.

Efficacy of acupuncture in reducing preoperative anxiety: a meta-analysis

Background. Acupuncture has been shown to reduce preoperative anxiety in several previous randomized controlled trials (RCTs). In order to assess the preoperative anxiolytic efficacy of acupuncture therapy, this study conducted a meta-analysis of an array of appropriate studies. Methods. Four electronic databases (MEDLINE, EMBASE, CENTRAL, and CINAHL) were searched up to February 2014. In the meta-analysis data were included from RCT studies in which groups receiving preoperative acupuncture treatment were compared with control groups receiving a placebo for anxiety. Results. Fourteen publications (N = 1,034) were included. Six publications, using the State-Trait Anxiety Inventory-State (STAI-S), reported that acupuncture interventions led to greater reductions in preoperative anxiety relative to sham acupuncture (mean difference = 5.63, P < .00001, 95% CI [4.14, 7.11]). Further eight publications, employing visual analogue scales (VAS), also indicated significant differences in preoperative anxiety amelioration between acupuncture and sham acupuncture (mean difference = 19.23, P < .00001, 95% CI [16.34, 22.12]). Conclusions. Acupuncture therapy aiming at reducing preoperative anxiety has a statistically significant effect relative to placebo or nontreatment conditions. Well-designed and rigorous studies that employ large sample sizes are necessary to corroborate this finding.

Interventions at caesarean section for reducing the risk of aspiration pneumonitis

BACKGROUND

Aspiration pneumonitis is a syndrome resulting from the inhalation of gastric contents. The incidence in obstetric anaesthesia has fallen, largely due to improved anaesthetic techniques and the increased use of regional anaesthesia at caesarean section. However, aspiration pneumonitis is still a cause of maternal morbidity and mortality, and it is important to use effective prophylaxis.

OBJECTIVES

To determine whether interventions given prior to caesarean section reduce the risk of aspiration pneumonitis in women with an uncomplicated pregnancy.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (30 April 2013).

SELECTION CRITERIA

Randomised controlled trials were included. Quasi-randomised trials were excluded.

DATA COLLECTION AND ANALYSIS

Review authors independently assessed the studies for inclusion, assessed risk of bias and carried out data extraction. Data entry was checked. Fixed-effect meta-analysis was used to combine data where it was reasonable to assume that studies were estimating the same underlying treatment effect. If substantial clinical or statistical heterogeneity was detected, we used random-effects analysis to produce an overall summary.

MAIN RESULTS

Thirty-two studies were included in this review. However, only 22 studies, involving 2658 women, provided data for analysis. All the women in the included studies had a caesarean section under general anaesthesia. The studies covered a number of comparisons, but were mostly small and of unclear or poor quality.When compared with no treatment or placebo, there was a significant reduction in the risk of intragastric pH < 2.5 with antacids (risk ratio (RR) 0.17, 95% confidence interval (CI) 0.09 to 0.32, two studies, 108 women), H2 antagonists (RR 0.09, 95% CI 0.05 to 0.18, two studies, 170 women) and proton pump antagonists (RR 0.26, 95% CI 0.14 to 0.46, one study 80 women). H2 antagonists were associated with a reduced the risk of intragastric pH < 2.5 at intubation when compared with proton pump antagonists (RR 0.39, 95% CI 0.16 to 0.97, one study, 120 women), but compared with antacids the findings were unclear. The combined use of 'antacids plus H2 antagonists' was associated with a significant reduction in the risk of intragastric pH < 2.5 at intubation when compared with placebo (RR 0.02, 95% CI 0.00 to 0.15, one study, 89 women) or compared with antacids alone (RR 0.12, 95% CI 0.02 to 0.92, one study, 119 women).

AUTHORS' CONCLUSIONS

The quality of the evidence was poor, but the findings suggest that the combination of antacids plus H2 antagonists was more effective than no intervention, and superior to antacids alone in preventing low gastric pH. However, none of the studies assessed potential adverse effects or substantive clinical outcomes. These findings are relevant for all women undergoing caesarean section under general anaesthesia.

Prophylaxis of intra- and postoperative nausea and vomiting in patients during cesarean section in spinal anesthesia

Background

This paper describes a randomized prospective study conducted in 308 patients undergoing caesarean section in spinal anaesthesia at a single hospital between 2010 and 2012 to find a suitable anti-emetic strategy for these patients.

Material/Methods

Spinal anesthesia was performed in left prone position, at L3/L4 with hyperbaric 0.5% Bupivacaine according to a cc/cm body height ratio. There were no opioids given peri-operatively. The patients received either no prophylaxis (Group I) or tropisetron and metoclopramide (Group II) or dimenhydrinate and dexamethasone (Group III), or tropisetron as a single medication (Group IV). The primary outcome was nausea and/or vomiting (NV) in the intraoperative, early (0–2 h) or late (2–24 h) postoperative period.

Multivariate statistical analysis was conducted with a regression analysis and a backward elimination of factors without significant correlation.

Results

All prophylactic agents significantly reduced NV incidence intraoperatively. Relative risk reduction for NV by prophylaxis was most effective (59.5%) in Group II (tropisetron and metoclopramide). In Group III (dimenhydrinate and dexamethasone), NV risk was reduced by 29.9% and by 28.7% in Group IV (tropisetron mono-therapy). The incidence of NV in the early (0–2 h) and the late (2–24 h) postoperative period was low all over (7.8%), but the relative risk reduction of NV in the early postoperative period was 54.1% (Group IV), 45.1% (Group III), and 34.8% (Group II), respectively. In the late postoperative period, there was no significant difference between the 4 groups.

Conclusions

We recommend a prophylactic medication with tropisetron 2 mg and metoclopramide 20 mg for patients during caesarean section. These agents are safe, reasonably priced, and highly efficient in preventing nausea and vomiting.

A comparison between acute pressure block of the sciatic nerve and acupressure: methodology, analgesia, and mechanism involved

Acupressure is an alternative medicine methodology that originated in ancient China. Treatment effects are achieved by stimulating acupuncture points using acute pressure. Acute pressure block of the sciatic nerve is a newly reported analgesic method based on a current neuroscience concept: stimulation of the peripheral nerves increases the pain threshold. Both methods use pressure as an intervention method. Herein, we compare the methodology and mechanism of these two methods, which exhibit several similarities and differences. Acupressure entails variation in the duration of manipulation, and the analgesic effect achieved can be short-or long-term. The acute effect attained with acupressure presents a scope that is very different from that of the chronic effect attained after long-term treatment. This acute effect appears to have some similarities to that achieved with acute pressure block of the sciatic nerve, both in methodology and mechanism. More evidence is needed to determine whether there is a relationship between the two methods.

Antiemetic effects of dexamethasone and ondansetron combination during cesarean sections under spinal anaesthesia

BACKGROUND

Nausea and vomiting are frequently seen in patients undergoing cesarean section (CS) under regional anesthesia. We aimed to compare the antiemetic efficacy of ondansetron and dexamethasone combination with that of the use of each agent alone to decrease the incidence of post-delivery intraoperative nausea and vomiting (IONV) during CS under spinal anesthesia.

OBJECTIVE

To compare the antiemetic efficacy of ondansetron and dexamethasone combination with that of the single use of each agent to decrease the incidence of postdelivery IONV during CS under spinal anesthesia.

METHODS

A randomized, prospective, double blind study was performed on 90 patients undergoing planned CS under spinal anesthesia. Patients received 4mg ondansetron in Group O, 8mg dexamethasone in GroupD, 4mg ondansetron+8mg dexamethasone in Group OD intravenously within 1-2 minutes after the umbilical cord was clamped. Frequency of postdelivery IONV episodes was recorded.

RESULTS

A total of 86 eligible patients were included in the study. There were 29 patients in Group O, 29 patients in Group D and 28 patients in Group OD. There were no statistically significant difference between the groups in terms of baseline characteristics and intraoperative managements. Frequency of intraoperative nausea, retching and vomiting experiences were similar between the groups (p>0.05).

CONCLUSION

Single dose 4mg ondansetron, 8mg dexamethasone, or combined use of 8mg dexamethasone+4mg ondansetron, given intravenously is all effective agents for the control of postdelivery IONV. Combined use of dexamethasone and ondansetron for the same indication does not seem to increase the antiemetic efficacy.