The Dose–Response of Nitrous Oxide in Postoperative Nausea in Patients Undergoing Gynecologic Laparoscopic Surgery: A Preliminary Study

Combination of dexamethasone and ondansetron in prophylaxis nausea and vomiting in gynecological operation

BACKGROUND

Postoperative nausea and vomiting occur in about 20-30% of women; however, some reports have estimated the rate at 70% in at-risk individuals. Gynecological and obstetrical operations are among the most frequent types of surgeries to be associated with nausea and vomiting postoperatively. Ondansetron and dexamethasone have been compared in a variety of studies for postoperative prophylaxis.

AIM OF THE STUDY

This study was conducted in order to compare the efficacy and safety of dexamethasone and ondansetron, alone or in combination, for prevention of postoperative nausea and vomiting in a sample of Iraqi women undergoing gynecological surgeries.

PATIENTS AND METHODS

The study was conducted in Al-Diwaniyah Province, a region belonging to the Mid-Euphrates sector of Iraq, at the Child and Maternity Teaching Hospital. The study started in June 2021 and the work with the research was accomplished in September 2022. The study included a total of 100 women undergoing different gynecological surgeries such as ovarian cystectomy, oophorectomy, ectopic pregnancy, total abdominal hysterectomy, and myomectomy. All participants involved in the study were categorized randomly into four groups, namely, dexamethasone, ondansetron, combined, and placebo groups.

RESULTS

The rates of nausea in the different groups were analyzed. The rates of nausea in dexamethasone, ondansetron, and combined groups revealed a significant decrease compared with that of placebo group (P < 0.05), and the rate was significantly lower in combined group when compared with dexamethasone and ondansetron groups (P < 0.05). The rate of nausea in combined group was significantly lower than that of dexamethasone and ondansetron groups. The rate of vomiting in combined group was significantly lower than that of placebo group and less than that of the dexamethasone group (P < 0.05).

CONCLUSION

Based on our study and previous reports, both dexamethasone and ondansetron are efficient and safe in preventing nausea and vomiting in gynecological operations; however, combination of both provides the best results.

Intraoperative Respiratory and Hemodynamic Strategies for Reducing Nausea, Vomiting, and Pain after Surgery: Systematic Review and Meta-Analysis

BACKGROUND

Despite improved medical treatment strategies, post-operative pain, nausea, and vomiting remain major challenges. This systematic review investigated the relationship between perioperative respiratory and hemodynamic interventions and postoperative pain, nausea, and vomiting.

METHODS

PubMed and Embase were searched on March 8, 2021 for randomized clinical trials investigating the effect of perioperative respiratory or hemodynamic interventions in adults undergoing non-cardiac surgery. Investigators reviewed trials for relevance, extracted data, and assessed risk of bias. Meta-analyses were performed when feasible. GRADE was used to assess the certainty in the evidence.

RESULTS

This review included 65 original trials; of these 48% had pain, nausea and/or vomiting as the primary focus. No reduction of postoperative pain was found in meta-analyses when comparing recruitment maneuvers with no recruitment, high (80%) to low (30%) fraction of oxygen, low (5-7 ml/kg) to high (9-12 ml/kg) tidal volume, or goal-directed hemodynamic therapy to standard care. In the meta-analysis comparing recruitment maneuvers with no recruitment maneuvers, patients undergoing laparoscopic gynecological surgery had less shoulder pain 24 hours postoperatively (mean difference in the numeric rating scale from 0 to 10: -1.1, 95% CI: -1.7, -0.5). In meta-analyses, comparing high to low fraction of inspired oxygen and goal-directed hemodynamic therapy to standard care in patients undergoing abdominal surgery, the risk of postoperative nausea and vomiting was reduced (odds ratio: 0.45, 95% CI: 0.24, 0.87 and 0.48, 95% CI: 0.27, 0.85). The certainty in the evidence was mostly very low to low. The results should be considered exploratory given the lack of pre-specified hypotheses and corresponding risk of Type 1 errors.

CONCLUSION

There is limited evidence regarding the impact of intraoperative respiratory and hemodynamic interventions on postoperative pain or nausea and vomiting. More definitive trials are needed to guide clinical care within this area. This article is protected by copyright. All rights reserved.

Intra-operative dexmedetomidine reduces early postoperative nausea but not vomiting in adult patients after gynaecological laparoscopic surgery: A randomised controlled trial

BACKGROUND

Few studies have investigated the use of dexmedetomidine in patients with a high risk of postoperative nausea and vomiting (PONV) following gynaecological laparoscopic surgery.

OBJECTIVE

To investigate if the intra-operative use of dexmedetomidine could reduce the incidence of PONV in this patient population.

DESIGN

A randomised, double-blind, placebo-controlled trial.

SETTING

A tertiary hospital in Beijing, China.

PATIENTS

130 adult patients scheduled for gynaecological laparoscopic surgery.

INTERVENTIONS

Patients in the dexmedetomidine group (Dex group, n = 65) received a loading dose of dexmedetomidine (0.5 μg kg over 10 min) before induction of anaesthesia, followed by a continuous infusion (0.1 μg kg h) until the end of surgery. Patients in the control group (Ctrl group, n = 65) received volume-matched normal saline. Propofol and remifentanil were used for induction and maintenance of anaesthesia. Intravenous patient-controlled analgesia with morphine was provided after surgery.

MAIN OUTCOME MEASURES

The incidence of 24-h PONV.

RESULTS

The incidence of nausea within the first 2 postoperative hours was lower in the Dex group than in the Ctrl group [0% (0/65) vs. 9% (6/65), P = 0.037]. The overall incidence of PONV within the first 2 postoperative hours was slightly lower in the Dex group than in the Ctrl group, but the difference was not statistically significant [5% (3/65) vs. 14% (9/65), P = 0.069]. There was no significant difference between the two groups regarding the incidence of 24-h PONV.

CONCLUSION

For adult patients undergoing gynaecological laparoscopic surgery, supplemental use of dexmedetomidine during general anaesthesia reduced the incidence of early postoperative nausea but not vomiting within the 24 h after surgery.

TRIAL REGISTRATION

Chinese Clinical Trial Registry ChiCTR-IPR-15006914.

[First experience with outpatient laparoscopic cholecystectomy in Tunisia]

Introduction

Laparoscopic cholecystectomy is the gold standard treatment for symptomatic gallstones. There is some debate as to whether it should be performed in outpatient surgery or in one-day surgery to improve patient safety. This study aimed to evaluate the impact of laparoscopic cholecystectomy performed in outpatient surgery versus one-day surgery on standards such as mortality, serious adverse events and quality of life.

Methods

We conducted a cross-sectional descriptive study in the Department of General Surgery at the Habib Thameur Hospital over the period May 2009-February 2010. We here report 67 cases of symptomatic vesical lithiasis treated with outpatient laparoscopic cholecystectomy (OLC). ASA III and IV patients, diabetic patients treated with sulfonamides or insulin, severely obese patients, patients over 65 years of age and under 18 years of age, patients with a history of major abdominal surgery, patients with suspected lithiasis of the common bile duct, acute cholecystitis or pancreatitis were excluded from the study. Patients had to reside within 50 km of the hospital and be accompanied by an adult to undergo OLC.

Results

Seventeen patients were included and then excluded from our study because of the perioperative detection of signs of acute cholecystitis or difficulties in dissection leading to subhepatic drainage using Redon catheter at the end of the intervention. Finally, our study included 50 patients, 7 men and 43 women; the average age was 48 years. Surgery was based on the most common procedures. After leaving the recovery room, patients were conducted in the outpatient sector where they received a liquid diet. The patients were examined before 7 o'clock in the evening and discharge was established on the basis of the possibility of establishing an oral analgesic treatment, patients tolerance to liquid diet, the lack of urinary disorder, patients acceptance for discharge and analgesic and anti-inflammatory treatment if needed. Thirty-nine patients (78%) were discharged from hospital and 11 were kept in hospital. Patients > 45 years of age, anesthesia duration > 70 minutes and post operative fatigue were identified as risk factors for unsuccessful discharge. No readmission was observed. Discharged patients were satisfied with the therapeutic protocol, resulting in excellent and good outcome in the majority of cases (94%).

Conclusion

Outpatient laparoscopic cholecystectomy seems to be as safe as day surgery laparoscopic cholecystectomy having low rate of complications and of hospital readmissions in some selected patients and lower surgery costs.

Nitrous oxide-based techniques versus nitrous oxide-free techniques for general anaesthesia

BACKGROUND

Nitrous oxide has been used for over 160 years for the induction and maintenance of general anaesthesia. It has been used as a sole agent but is most often employed as part of a technique using other anaesthetic gases, intravenous agents, or both. Its low tissue solubility (and therefore rapid kinetics), low cost, and low rate of cardiorespiratory complications have made nitrous oxide by far the most commonly used general anaesthetic. The accumulating evidence regarding adverse effects of nitrous oxide administration has led many anaesthetists to question its continued routine use in a variety of operating room settings. Adverse events may result from both the biological actions of nitrous oxide and the fact that to deliver an effective dose, nitrous oxide, which is a relatively weak anaesthetic agent, needs to be given in high concentrations that restrict oxygen delivery (for example, a common mixture is 30% oxygen with 70% nitrous oxide). As well as the risk of low blood oxygen levels, concerns have also been raised regarding the risk of compromising the immune system, impaired cognition, postoperative cardiovascular complications, bowel obstruction from distention, and possible respiratory compromise.

OBJECTIVES

To determine if nitrous oxide-based anaesthesia results in similar outcomes to nitrous oxide-free anaesthesia in adults undergoing surgery.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2014 Issue 10); MEDLINE (1966 to 17 October 2014); EMBASE (1974 to 17 October 2014); and ISI Web of Science (1974 to 17 October 2014). We also searched the reference lists of relevant articles, conference proceedings, and ongoing trials up to 17 October 2014 on specific websites (http://clinicaltrials.gov/, http://controlled-trials.com/, and http://www.centerwatch.com).

SELECTION CRITERIA

We included randomized controlled trials (RCTs) comparing general anaesthesia where nitrous oxide was part of the anaesthetic technique used for the induction or maintenance of general anaesthesia (or both) with any general anaesthesia using a volatile anaesthetic or propofol-based maintenance of anaesthesia but no nitrous oxide for adults undergoing surgery. Our primary outcome was inhospital case fatality rate. Secondary outcomes were complications and length of stay.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted the outcome data. We used meta-analysis for data synthesis. Heterogeneity was examined with the Chi² test and by calculating the I² statistic. We used a fixed-effect model if the measure of inconsistency was low for all comparisons (I² statistic < 50%); otherwise we used a random-effects model for measures with high inconsistency. We undertook subgroup analyses to explore inconsistency and sensitivity analyses to evaluate whether the results were robust. We assessed the quality of evidence of the main outcomes using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) system.

MAIN RESULTS

We included 35 trials (13,872 adult participants). Seven included studies were at low risk of bias. We identified eight studies as awaiting classification since we could not obtain the full texts, and had insufficient information to include or exclude them. We included data from 24 trials for quantitative synthesis. The results of meta-analyses showed that nitrous oxide-based techniques increased the incidence of pulmonary atelectasis (odds ratio (OR) 1.57, 95% confidence interval (CI) 1.18 to 2.10, P = 0.002), but had no effects on the inhospital case fatality rate, the incidence of pneumonia, myocardial infarction, stroke, severe nausea and vomiting, venous thromboembolism, wound infection, or the length of hospital stay. The sensitivity analyses suggested that the results of the meta-analyses were all robust except for the outcomes of pneumonia, and severe nausea and vomiting. Two trials reported length of intensive care unit (ICU) stay but the data were skewed so were not pooled. Both trials reported that nitrous oxide-based techniques had no effects on the length of ICU stay. We rated the quality of evidence for two outcomes (pulmonary atelectasis, myocardial infarction) as high, four outcomes (inhospital case fatality rate, stroke, venous thromboembolism, length of hospital stay) as moderate, and three (pneumonia, severe nausea and vomiting, wound infection rate) as low.

AUTHORS' CONCLUSIONS

Given the evidence from this Cochrane review, the avoidance of nitrous oxide may be reasonable in participants with pre-existing poor pulmonary function or at high risk of postoperative nausea and vomiting. Since there are eight studies awaiting classification, selection bias may exist in our systematic review.

Efficacy of orally disintegrating film of ondansetron versus intravenous ondansetron in prophylaxis of postoperative nausea and vomiting in patients undergoing elective gynaecological laparoscopic procedures: A prospective randomised, double-blind placebo-controlled study

Background and Aims:

Ondansetron is one of the most widely used drugs for postoperative nausea and vomiting (PONV) prophylaxis. Orally disintegrating film (ODF) formulations are relatively recent innovations. We evaluated the efficacy of ODF of ondansetron for the prophylaxis of PONV.

Methods:

One hundred and eighty American Society of Anaesthesiologists-I or II women, in the age group 18-65 years, scheduled for elective gynaecological laparoscopic procedures were studied in a prospective randomised, double-blind, placebo-controlled trial. The patients were randomised into four groups: Placebo, intravenous (IV) ondansetron 4 mg, ODF of ondansetron 4 mg (ODF4) and 8 mg (ODF8) groups. PONV was assessed in two epochs of 0-6 and 7-24 h. Primary outcome measure was the incidence of PONV and secondary outcome measures were severity of nausea, need for rescue anti-emetic, analgesic consumption, time to oral intake, overall patient satisfaction and side effects such as headache and dizziness. PONV was compared using analysis of variance or Mann–Whitney U-test as applicable.

Results:

Data of 173 patients were analysed. The incidence of postoperative nausea was significantly lower (P = 0.04) only during the 0-6 h in the ODF8 group when compared with the placebo group. During the 0-6 h interval postoperatively, the ODF8 group had a significantly lower incidence of vomiting when compared with the placebo (P = 0.002) and the IV group (P = 0.044). During the 0-24 h interval postoperatively, ODF4 (P = 0.01) and ODF8 (P = 0.002) groups had a significantly lower incidence of vomiting compared to the placebo group.

Conclusions:

Orally disintegrating film of ondansetron is an efficacious, novel, convenient and may be a cost-effective option for the prophylaxis of PONV.

Nitrous oxide-related postoperative nausea and vomiting depends on duration of exposure

BACKGROUND

Inclusion of nitrous oxide in the gas mixture has been implicated in postoperative nausea and vomiting (PONV) in numerous studies. However, these studies have not examined whether duration of exposure was a significant covariate. This distinction might affect the future place of nitrous oxide in clinical practice.

METHODS

PubMed listed journals reporting trials in which patients randomized to a nitrous oxide or nitrous oxide-free anesthetic for surgery were included, where the incidence of PONV within the first 24 postoperative hours and mean duration of anesthesia was reported. Meta-regression of the log risk ratio for PONV with nitrous oxide (lnRR PONVN2O) versus duration was performed.

RESULTS

Twenty-nine studies in 27 articles met the inclusion criteria, randomizing 10,317 patients. There was a significant relationship between lnRR PONVN2O and duration (r = 0.51, P = 0.002). Risk ratio PONV increased 20% per hour of nitrous oxide after 45 min. The number needed to treat to prevent PONV by avoiding nitrous oxide was 128, 23, and 9 where duration was less than 1, 1 to 2, and over 2 h, respectively. The risk ratio for the overall effect of nitrous oxide on PONV was 1.21 (CIs, 1.04-1.40); P = 0.014.

CONCLUSIONS

This duration-related effect may be via disturbance of methionine and folate metabolism. No clinically significant effect of nitrous oxide on the risk of PONV exists under an hour of exposure. Nitrous oxide-related PONV should not be seen as an impediment to its use in minor or ambulatory surgery.

Does anaesthesia with nitrous oxide affect mortality or cardiovascular morbidity? A systematic review with meta-analysis and trial sequential analysis

BACKGROUND

The role of nitrous oxide in modern anaesthetic practice is contentious. One concern is that exposure to nitrous oxide may increase the risk of cardiovascular complications. ENIGMA II is a large randomized clinical trial currently underway which is investigating nitrous oxide and cardiovascular complications. Before the completion of this trial, we performed a systematic review and meta-analysis, using Cochrane methodology, on the outcomes that make up the composite primary outcome.

METHODS

We used conventional meta-analysis and trial sequential analysis (TSA). We reviewed 8282 abstracts and selected 138 that fulfilled our criteria for study type, population, and intervention. We attempted to contact the authors of all the selected publications to check for unpublished outcome data.

RESULTS

Thirteen trials had outcome data eligible for our outcomes. We assessed three of these trials as having a low risk of bias. Using conventional meta-analysis, the relative risk of short-term mortality in the nitrous oxide group was 1.38 [95% confidence interval (CI) 0.22-8.71] and the relative risk of long-term mortality in the nitrous oxide group was 0.94 (95% CI 0.80-1.10). In both cases, TSA demonstrated that the data were far too sparse to make any conclusions. There were insufficient data to perform meta-analysis for stroke, myocardial infarct, pulmonary embolus, or cardiac arrest.

CONCLUSION

This systematic review demonstrated that we currently do not have robust evidence for how nitrous oxide used as part of general anaesthesia affects mortality and cardiovascular complications.

The perioperative use of nitrous oxide: renaissance of an old gas or funeral of an ancient relict?

PURPOSE OF REVIEW

Conflicting reports about adverse events following nitrous oxide (N(2)O) application have spurred a discussion whether N(2)O should be abandoned from clinical practice. Concurrently, N(2)O is increasingly used as a single anesthetic agent in medical procedures. This article reviews and discusses reports about the present use of N(2)O.

RECENT FINDINGS

Multiple publications demonstrate an increasing use of N(2)O as a procedural analgesic and sedative. Results from the Evaluation of Nitrous Oxide in the Gas Mixture for Anesthesia trial have been contrasted by recent studies reporting no increased risk for perioperative complications, particularly related to the cardiovascular and cerebrovascular system. Recent studies show that electroencephalogram-based anesthesia depth monitoring is not compatible with the use of N(2)O because of its distinct influence on electroencephalogram wave patterns. The clinical relevance of the proposed neurotoxicity, immunosuppression and influence on methionine metabolism remains unclear. Recently, its acute and long-term analgesic potency has been proven. Occupational exposure might pose a relevant health hazard.

SUMMARY

Based on the present literature, abolishment of N(2)O is controversial. When avoided in patients at risk for adverse events, N(2)O is still a valuable supplement to general anesthesia and a potent procedural analgesic drug. In the latter, its use by nonanesthesiologists should be discouraged.

Risk factors for nausea and vomiting after day care general anesthesia in mentally challenged patients undergoing dental treatment

Clinically, the incidence of postoperative nausea and vomiting (PONV) may be higher in mentally challenged patients than in normal healthy patients. The aim of this study was to investigate the risk factors for PONV after day care general anesthesia in mentally challenged patients undergoing dental treatment. We analyzed data on 231 day care general anesthesia cases involving mentally challenged patients undergoing dental treatment. Anesthetic records for the past 5 years were investigated retrospectively. Ten items (age, body weight, sex, duration of general anesthesia, use of propofol, use of sevoflurane, use of nitrous oxide, use of neostigmine, treatment accompanied with bleeding, and transfusion volume) were selected as risk factors for PONV. Postoperative nausea and vomiting was evaluated using the postoperative check sheet and linear discriminant analysis was performed to distinguish PONV incidence using the 10 items as independent variables. The reliability of the linear discriminant function was evaluated using a misjudgment rate and information criteria (AIC). Postoperative nausea and vomiting was observed in 13 cases out of 231 cases. The discriminant function with the smallest AIC (-25.0718) consisted of two independent variables: y=-0.077x(1)-0.001x(2)+0.0716(x(1)=use of propofol, x(2)=age). The misjudgment rate was 31.6%. This result suggests that PONV decreases when propofol is used and that the incidence of PONV decreases with age. To investigate other risk factors, an additional analysis was performed using 83 out of the 231 cases in which sevoflurane was used as an anesthetic agent. The results of the subgroup analysis suggest that the incidence of PONV decreases in male patients and higher weight patients, although the patient's body weight may be related to age, as the study cohort included many children. It is suggested that the major risks for PONV in mentally challenged patients after day care general anesthesia are no use of propofol, lower age, female sex and lower weight.

Postoperative nausea and vomiting in a gynecological and obstetrical population in South Eastern Nigeria

BACKGROUND

To determine the incidence of Postoperative nausea and vomiting (PONV) in a high risk surgical group following studies in other predominately black populations that showed a lower rate of postoperative nausea and vomiting than that reported from Caucasian and Oriental populations.

METHODS

A retrospective observational survey was conducted in the University of Nigeria Teaching Hospital (UNTH), Enugu, Nigeria to determine the incidence of PONV within forty-eight hours of anesthesia in an obstetrical (caesarean sections only) and gynecological population that underwent regional and general anesthesia. The study took place from December 2007-April 2009 (16 months) for the gynecological population and from May 2008 to May 2010 (25 months) for the obstetrical population. The folders of 300 patients were randomly reviewed for demographics, anesthetic technique, diagnosis and documented records of PONV within 48 hours of anesthesia.

RESULTS

A total of 300 obstetrical and gynecological patients were used in this study. Twelve women vomited within forty-eight hours of anesthesia (12/300 or 4.0%). Nine patients vomited in the gynecological population (9/112) or 8% of the gynecological population and (3/186) or 1.6% in the obstetric population. All patients were American Society of Anesthesiologists (ASA) 1-4 including surgical emergencies.

CONCLUSION

The incidence of PONV in this surgical population is lower than that from most of the studies reviewed. This might be due to an inherent ethnic/racial variation. The economic implication of spending on expensive anti-emetics means more money can diverted to other needs.

Update on the management of postoperative nausea and vomiting and postdischarge nausea and vomiting in ambulatory surgery

Postoperative nausea and vomiting (PONV) continues to be one of the most common complaints following surgery, occurring in more than 30% of surgeries, or as high as 70% to 80% in certain high-risk populations without prophylaxis. The 5-hydroxytryptamine type 3 (5-HT(3)) receptor antagonists continue to be the mainstay of antiemetic therapy, but newer approaches, such as neurokinin-1 antagonists, a longer-acting serotonin receptor antagonist, multimodal management, and novel techniques for managing high-risk patients are gaining prominence. The related problem of postdischarge nausea and vomiting (PDNV) has received increasing attention from health care providers. The issues of PONV and PDNV are especially significant in the context of ambulatory surgeries, which comprise more than 60% of the combined 56.4 million ambulatory and inpatient surgery visits in the United States. Because of the relatively brief period that ambulatory patients spend in health care facilities, it is particularly important to prevent and treat PONV and PDNV swiftly and effectively.

[Use of nitrous oxide in Uruguay]

BACKGROUND

Nitrous oxide (N2O) is a medicinal gas that has been used for anesthesia for over a century and a half. As evidence of the adverse effects of N2O have been contrasted with the good safety profiles of new anesthetic agents, use of the older gas has declined.

OBJECTIVE

To describe and analyze the use of N2O for anesthesia in the Eastern Republic of Uruguay. To describe the use of other drugs for general anesthesia.

METHODS

The study had 2 phases. In the first phase, information on the use of N2O and other drugs for general anesthesia was obtained from the medical records of a sample of patients who underwent surgery between November 2007 and November 2008 at nationally important hospitals. In the second phase 80 physician anesthesiologists were surveyed to obtain information on their reported use of N2O for general anesthesia. The respondents were found working during the first half of 2008.

RESULTS

A total of 104 patients' records were read and 80 anesthesiologists were surveyed. We found that 31 (29.8%) patients received N2O during anesthesia. The survey showed that 62 (77.5%) of the anesthesiologists had used N2O in the last 6 months. Nine (50%) of the anesthesiologists who had not used N2O said their reason was that it was unavailable. The other 9 referred either to the risk of postoperative nausea and/or vomiting (n = 6) or the fact of having better alternatives (n = 9).

CONCLUSION

This study shows that N2O is little used in current anesthesia practice. The tendency in Uruguay continues to be toward declining use.