Supplemental oxygen for prevention of nausea and vomiting after breast surgery

Background. Administration of supplemental oxygen 80% has beenshown to halve the incidence of postoperative nausea and vomiting(PONV). We tested the efficacy of supplemental oxygen 50% indecreasing the incidence of PONV after breast surgery. Methods. One hundred patients receiving standardized sevofluraneanaesthesia were randomly assigned to two groups: oxygen 30%administration (Group 30); and oxygen 50% administration (Group50). Oxygen was administered during surgery and for 2 hfrom the end of surgery. Results. The incidence of PONV over 24 h after surgeryshowed no difference between the groups: 82% in Group 30 and89% in Group 50. However, during the postoperative oxygen administration,eight patients vomited in Group 30, compared with none in Group50 (P<0.05). After oxygen therapy ceased, there was no differencein the incidence of vomiting between the groups. Nausea andneed for rescue antiemetics did not differ between the groups. Conclusion. The incidence of vomiting decreased during the shortpostoperative administration of supplemental oxygen 50%. However,perioperative oxygen 50% administration did not prevent PONVover the 24-h follow-up period in patients undergoing breastsurgery performed under general anaesthesia. Br J Anaesth 2003; 91: 284–7     

Volatile anaesthetics may be the main cause of early but not delayed postoperative vomiting: a randomized controlled trial of factorial design

Background. Despite intensive research, the main causes of postoperativenausea and vomiting (PONV) remain unclear. We sought to quantifythe relative importance of operative, anaesthetic and patient-specificrisk factors to the development of PONV. Methods. We conducted a randomized controlled trial of 1180children and adults at high risk for PONV scheduled for electivesurgery. Using a five-way factorial design, we randomly assignedsubjects by gender who were undergoing specific operative procedures,to receive various combinations of anaesthetics, opioids, andprophylactic antiemetics. Results. Of the 1180 patients, 355 (30.1% 95% CI (27.5–32.7%))had at least one episode of postoperative vomiting (PV) within24 h post-anaesthesia. In the early postoperative period (0–2h), the leading risk factor for vomiting was the use of volatileanaesthetics, with similar odds ratios (OR (95% CI)) being foundfor isoflurane (19.8 (7.7–51.2)), enflurane (16.1 (6.2–41.8))and sevoflurane (14.5 (5.6–37.4)). A dose–responserelationship was present for the use of volatile anaesthetics.In contrast, no dose response existed for propofol anaesthesia.In the delayed postoperative period (2–24 h), the mainpredictors were being a child (5.7 (3.0–10.9)), PONV inthe early period (3.4 (2.4–4.7)) and the use of postoperativeopioids (2.5 (1.7–3.7)). The influence of the antiemeticswas considerably smaller and did not interact with anaestheticor surgical variables. Conclusion. Volatile anaesthetics were the leading cause ofearly postoperative vomiting. The pro-emetic effect was largerthan other risk factors. In patients at high risk for PONV,it would therefore make better sense to avoid inhalational anaesthesiarather than simply to add an antiemetic, which may still beneeded to prevent or treat delayed vomiting. Br J Anaesth 2002; 88: 659–68     

Cost-effectiveness of three combinations of antiemetics in the prevention of postoperative nausea and vomiting

Background. This study compares the cost-effectiveness of threecombinations of antiemetics in the prevention of postoperativenausea and vomiting (PONV). Methods. We conducted a prospective, double-blind study. NinetyASA I–II females, 18–65 yr, undergoing general anaesthesiafor major gynaecological surgery, with standardized postoperativeanalgesia (intrathecal 0.2 mg plus i.v. PCA morphine), wererandomly assigned to receive: ondansetron 4 mg plus droperidol1.25 mg after induction and droperidol 1.25 mg 12 h later (Group1); dexamethasone 8 mg plus droperidol 1.25 mg after inductionand droperidol 1.25 mg 12 h later (Group 2); ondansetron 4 mgplus dexamethasone 8 mg after induction and placebo 12 h later(Group 3). A decision analysis tree was used to divide eachgroup into nine mutually exclusive subgroups, depending on theincidence of PONV, need for rescue therapy, side effects andtheir treatment. Direct cost and probabilities were calculatedfor each subgroup, then a cost-effectiveness analysis was conductedfrom the hospital point of view. Results. Groups 1 and 3 were more effective (80 and 70%) thanGroup 2 (40%, P=0.004) in preventing PONV but also more expensive.Compared with Group 2, the incremental cost per extra patientwithout PONV was €6.99 (95% CI, –1.26 to 36.57) forGroup 1 and €13.55 (95% CI, 0.89–132.90) for Group3. Conclusion. Ondansetron+droperidol is cheaper and at least aseffective as ondansetron+ dexamethasone, and it is more effectivethan dexamethasone+droperidol with a reasonable extra cost. Br J Anaesth 2003; 91: 589–92     

Supplemental oxygen does not reduce postoperative nausea and vomiting after thyroidectomy

Background. Supplemental intra-operative oxygen 80% halves theincidence of nausea and vomiting after open and laparoscopicabdominal surgery, perhaps by ameliorating intestinal ischaemiaassociated with abdominal surgery. It is unlikely that thyroidsurgery compromises intestinal perfusion. We therefore testedthe hypothesis that supplemental perioperative oxygen does notreduce the risk of postoperative nausea and vomiting (PONV)after thyroidectomy. Methods. One hundred and fifty patients undergoing thyroidectomywere given sevoflurane anaesthesia. After induction, patientswere randomly assigned to the following treatments: (i) 30%oxygen, (ii) 80% oxygen, or (iii) 30% oxygen with droperidol0.625 mg. Results. The overall incidence of nausea during the first 24 hafter surgery was 48% in the patients given oxygen 30%, 46%in those given oxygen 80%, and 22% in those given droperidol(P=0.004). There were no significant differences between theoxygen 30% and 80% groups in incidence or severity of PONV,the need for rescue antiemetics, or patient satisfaction. Droperidolsignificantly shortened the time to first meal. Conclusions. Supplemental oxygen was ineffective in preventingnausea and vomiting after thyroidectomy, but droperidol reducedthe incidence. Br J Anaesth 2003; 91: 857–61     

Dolasetron prophylaxis reduces nausea and postanaesthesia recovery time after remifentanil infusion during monitored anaesthesia care for extracorporeal shock wave lithotripsy

Background. Remifentanil is used as an analgesic for differentprocedures performed during monitored anaesthesia care. Opioid-inducednausea and vomiting can be troublesome. Methods. This prospective, randomized, double-blind study wasperformed to evaluate the efficacy of prophylaxis with dolasetronin reducing the frequency of postoperative nausea and durationof discharge time. Forty urological patients, undergoing electiveambulatory extracorporeal shock wave lithotripsy (ESWL) receivedrandomly either dolasetron 12.5 mg i.v. (Group 1) or placebo(Group 2) 10 min before a patient-adapted continuous infusionof remifentanil 0.15–0.4 µg kg^–1 min^–1was administered. Frequency and intensity (VAS 0–100 mm)of nausea, retching, and vomiting were assessed by patientsand blinded investigators during and after the procedure. Results. Patient characteristics, baseline values, durationof ESWL, and total dose of remifentanil did not differ betweengroups. The frequency (Group 1/Group 2; 20/55%; P<0.05) andmean (SD) maximal intensity [15 (9)/45 (14) mm; P<0.05] ofnausea during 24 h was significantly reduced after dolasetronand discharge times in Group 1 were less than Group 2[22 (14)/45 (28) min; P<0.05]. Br J Anaesth 2003; 90: 194–8     

Efficacy of three doses of tramadol with bupivacaine for caudal analgesia in paediatric inguinal herniotomy

Background. This study was designed to evaluate the analgesicefficacy of three doses of tramadol, administered caudally withbupivacaine, in providing postoperative pain relief in children. Methods. Eighty children, aged between 2 and 8 yr, undergoinginguinal herniotomy were randomly allocated to receive bupivacaine0.25% 0.75 ml kg^–1 (Group B; n=20), bupivacaine 0.25%0.75 ml kg^–1 with tramadol 1 mg kg^–1 (Group BT1;n=20), bupivacaine 0.25% 0.75 ml kg^–1 with tramadol 1.5mg kg^–1 (Group BT1.5; n=20), or bupivacaine 0.25% 0.75ml kg^–1 with tramadol 2 mg kg^–1 (Group BT2; n=20)by the caudal route immediately after induction of general anaesthesia.Heart rate, arterial pressure and oxygen saturation were monitored.Postoperative pain was assessed at regular intervals for 24h using All India Institute of Medical Sciences pain score.Analgesia was supplemented whenever pain score was 4. Durationof analgesia and requirement for additional analgesics was noted. Results. Duration of analgesia was longer in Group BT2 [(mean(SD) 12 (0.9) h] compared with Group B [4 (1) h], Group BT1[8 (0.9) h], or Group BT1.5 [11 (1) h]; all P<0.001. Totalconsumption of rescue analgesic was significantly lower in groupBT2 compared with other groups (P<0.001). There were no significantchanges in heart rate, arterial pressure and oxygen saturationbetween groups. Adverse effects were not observed. Conclusions. Caudal tramadol 2 mg kg^–1, combined withbupivacaine 0.25% 0.75 ml kg^–1, provided longer durationof postoperative analgesia and reduced requirement for rescueanalgesic compared with tramadol 1 mg kg^–1 or 1.5 mg kg^–1in children undergoing inguinal herniotomy.     

Dexamethasone is a cost-effective alternative to ondansetron in preventing PONV after paediatric strabismus repair

This study evaluated the antiemetic efficacy, cost-effectivenessand clinical utility of prophylactic ondansetron and dexamethasonecompared with placebo in the prevention of postoperative nauseaand vomiting (PONV) in 135 children (2–15 yr, ASA I–II)undergoing strabismus repair. After induction with halothaneand nitrous oxide in oxygen or i.v. thiopental, the childrenreceived i.v. dexamethasone 1 mg kg^–1 to a maximumof 25 mg, ondansetron 100 µg kg^–1to a maximum of 4 mg or placebo (n=45). Episodes of PONVwere recorded for the first 24 h after the operation. Trueoutcome measures (parental satisfaction score, duration of stayin the postanaesthesia care unit and fast tracking time), therapeuticoutcome measures (number needed to prevent (NNTP) PONV) andthe cost to benefit a child with each drug were analysed. Theincidence and severity of PONV in the first 24 h were significantlyless in the dexamethasone and ondansetron groups than in theplacebo group (P<0.05). The incidence (P=0.04) and severity(P=0.03) of PONV at the 6–24 h epoch were significantlyless in the dexamethasone group than in the ondansetron group.Recovery time (P=0.07), fast tracking time (P=0.6), parentalsatisfaction scores (P=0.08) and NNTP PONV were comparable (NNTP=2)in both the ondansetron and the dexamethasone group. The costto benefit a child with dexamethasone was approximately 22 timesless than that of ondansetron. Br J Anaesth 2001; 86: 84–9     

Antiemetic and analgesic-sparing effects of diphenhydramine added to morphine intravenous patient-controlled analgesia

Background. This study was designed to examine the analgesicand dose-related antiemetic efficacy of diphenhydramine–morphinemixture for intravenous patient-controlled analgesia (PCA). Methods. Healthy women, undergoing abdominal total hysterectomywere recruited to this double-blinded randomized placebo-controlledstudy. Patients were randomly allocated to one of three groups(n=40 each). In group 1, patients received saline at inductionand morphine 1 mg ml^–1 alone for postoperative PCA. Patientsin groups 2 and 3 received diphenhydramine 30 mg i.v. at inductionand were given a 1.2:1 or a 4.8:1 ratio, respectively, of diphenhydramine–morphinemixture for postoperative PCA. Results. A total of 112 patients completed the study. The incidenceof postoperative nausea (31.6% vs 67.6%, P<0.01) and vomiting(15.8% vs 40.5%, <0.05) was significantly lower in group3 than in group 1. Furthermore, the incidence of severe nauseawas significantly lower in group 3 than in group1 (2.6% vs 24.3%,P<0.05). The rescue antiemetic requirements were also significantlyless in group 3 than in group 1 (5.3% vs 24.3%, P<0.05).However, there was no significant difference between group 2and group 1 in any of the comparisons. Pain intensity, 24-hmorphine consumption and diphenhydramine-related side-effects,such as sedation or dry mouth, did not differ among the threegroups. Conclusion. An initial bolus of diphenhydramine 30 mg at anaestheticinduction followed by postoperative PCA with a 4.8:1, but not1.2:1, diphenhydramine–morphine mixture provides an effectiveantiemetic efficacy without morphine-sparing effects.     

Randomized comparison of two anti-emetic strategies in high-risk patients undergoing day-case gynaecological surgery

Background: Postoperative nausea and vomiting (PONV) is a significant causeof morbidity among patients undergoing general anaesthesia.The optimal strategy for prevention of PONV, however, remainsunclear. This study compared two commonly used prophylacticstrategies in high-risk, day-case, gynaecological surgery patients. Methods: We conducted a randomized trial comparing sevoflurane combinedwith dolasetron (SD), with propofol-based total intravenousanaesthesia (TIVA) in 126 high-risk patients undergoing day-casegynaecological surgery. The primary endpoints included the incidenceand severity of nausea or vomiting before discharge and theincidence of nausea or vomiting between discharge and 24 h.To identify the factors most predictive of a complete response(no PONV at any time within the 24 h period), multiplelogistic regression models were fitted. Results: Before discharge, there was no significant difference betweenthe two treatment groups with respect to nausea and vomitingoutcomes (P = 0.3). Post-discharge nausea and vomiting (PDNV),however, were significantly more common for patients in theTIVA group (nausea, P = 0.004 and vomiting, P = 0.03). Typeof anaesthetic, adjusted for weight and anaesthesia durationwas significantly associated with complete response (odds ratio= 2.7, 95% confidence interval = 1.15 to 6.4). Conclusions: Although both TIVA and dolasetron prophylaxis reduce the predictedrate of PONV in the early postoperative period, the anti-emeticeffects of propofol are short-lived. A longer-acting drug suchas dolasetron may therefore be necessary to prevent PDNV.     

Efficacy of prophylactic ketamine in preventing postoperative shivering

Background. Treatment with ketamine and pethidine is effectivein postoperative shivering. The aim of this study was to comparethe efficacy of low-dose prophylactic ketamine with that ofpethidine or placebo in preventing postoperative shivering. Methods. A prospective randomized double-blind study involved90 ASA I and II patients undergoing general anaesthesia. Patientswere randomly allocated to receive normal saline (Group S, n=30),pethidine 20 mg (Group P, n=30) or ketamine 0.5 mg kg^–1(Group K, n=30) intravenously 20 min before completion of surgery.The anaesthesia was induced with propofol 2 mg kg^–1, fentanyl1 µg kg^–1 and vecuronium 0.1 mg kg^–1. It wasmaintained with sevoflurane 2–4% and nitrous oxide 60%in oxygen. Tympanic temperature was measured immediately afterinduction of anaesthesia, 30 min after induction and beforeadministration of the study drug. An investigator, blinded tothe treatment group, graded postoperative shivering using afour-point scale and postoperative pain using a visual analoguescale (VAS) ranging between 0 and 10. Results. The three groups did not differ significantly regardingpatient characteristics. The number of patients shivering onarrival in the recovery room, and at 10 and 20 min after operationwere significantly less in Groups P and K than in Group S. Thetime to first analgesic requirement in Group S was shorter thanin either Group K or Group P (P<0.005). There was no differencebetween the three groups regarding VAS pain scores. Conclusion. Prophylactic low-dose ketamine was found to be effectivein preventing postoperative shivering.     

Prophylactic ondansetron does not improve patient satisfaction in women using PCA after Caesarean section

Eighty-one consenting women undergoing elective Caesarean sectionunder spinal anaesthesia were randomly divided into two groups.In Group O patients, ondansetron 4 mg was given intravenouslyat the end of the surgery and 8 mg added to the morphine solutionin the PCA syringe. Patients in Group P received only morphinevia PCA syringe. Analgesia and nausea were measured until PCAwas discontinued 24 h after the operation. Women in the twogroups were similar with respect to age, duration of use ofthe PCA, amount of morphine used, previous history of PONV,and incidence of motion sickness and morning sickness duringthe current pregnancy. The number of women who complained ofnausea and those needing rescue antiemetic medication was significantlyless in Group O. However, there was no statistically significantdifference between the two groups in the patient’s perceptionof the control of nausea and their overall satisfaction. Itwas noted that PONV was more frequent among women who had significantmorning sickness during early pregnancy and ondansetron wasbeneficial in reducing PONV in these women. Although the ondansetronreduced the incidence of PONV and the need for further antiemeticmedication, this did not affect patient’s satisfactionregarding their postoperative care. Br J Anaesth 2001; 87: 502–4     

Nausea and vomiting after fast-track cardiac anaesthesia

Background. The aim of this study was to determine the prevalenceof postoperative nausea and vomiting (PONV) after fast-trackcardiac anaesthesia, risk factors for PONV and its influenceon the length of stay in the intensive care unit (ICU). Methods. A prospective study was performed in the cardiothoracicICU (CTICU) of a university hospital; 1221 consecutive patientsundergoing fast-track anaesthesia (FTCA) in cardiac surgerywere enrolled in the study. Severity of PONV was assessed immediatelyafter extubation and then every hour until discharge from theCTICU. Metoclopramide 10 mg i.v. was used as a first-line rescuemedication and ondansetron 4 mg i.v. as second-line rescue medicationfor PONV. Results. Nausea was reported in 240 (19.7%) patients, and vomitingin 53 (4.3%). A total of 269 (22%) patients were treated withmetoclopramide and 38 (3.1%) with metoclopramide and ondansetron.The latter was effective in all cases. Risk factors for PONVwere age less than 60 yr, female gender and previous historyof PONV. Discharge from the CTICU was delayed for a few hoursbecause of PONV in eight patients, all of whom were dischargedthe same day. Conclusions. The incidence of PONV is relatively low after FTCAand does not prolong ICU stay. Prophylactic administration ofanti-emetic drugs before FTCA is not necessary. Br J Anaesth 2003; 91: 214–17     

Effect of intraoperative intravenous crystalloid infusion on postoperative nausea and vomiting after gynaecological laparoscopy: comparison of 30 and 10 ml kg(-1)

Background. I.V. fluid administration has been shown to reducepostoperative nausea and vomiting (PONV). The optimum dose isunknown. We tested the hypothesis that administration of i.v.crystalloid of 30 ml kg^–1 would reduce the incidence ofPONV compared with 10 ml kg^–1 of the same fluid. Methods. A total of 141 ASA I female patients undergoing electivegynaecological laparoscopy were randomized, in double-blindfashion, to receive either 10 ml kg^–1 (n=71; CSL-10 group)or 30 ml kg^–1 (n=70; CSL-30 group) of i.v. compound sodiumlactate (CSL). Results. In the first 48 h after anaesthesia, the incidenceof vomiting was lower in the CSL-30 group than in the CSL-10group (8.6% vs 25.7%, P=0.01). Anti-emetic use was less in theCSL-30 group at 0.5 h (2.9% vs 14.3%, P=0.04). The incidenceof severe nausea was significantly reduced in the treatmentgroup at awakening (2.9% vs 15.7%, P=0.02), 2 h (0.0% vs 8.6%,P=0.04) and cumulatively (5.7% vs 27.1%, P=0.001). The numbersneeded to treat to prevent vomiting, severe nausea and antiemeticuse in the first 48 h were 6, 5 and 6, respectively. Conclusion. I.V. administration of CSL 30 ml kg^–1 to healthywomen undergoing day-case gynaecological laparoscopy reducedthe incidence of vomiting, nausea and anti-emetic use when comparedwith CSL 10 ml kg^–1.     

Prevention of post-operative nausea and vomiting. Randomised comparison of dolasetron versus dolasetron plus dexamethasone

BACKGROUND: Postoperative nausea and vomiting (PONV) are frequent complications after operations.The aim of this study was to assess the efficacy of combined dolasetron plus dexamethasone versus dolasetron alone with respect to the incidence and severity of emetic symptoms and patients satisfaction. METHODS: In a prospective, randomised, double-blind study, 150 patients scheduled for hysterectomy or breast surgery were allocated to one of the following two groups: group A received 50 mg dolasetron orally and group B 50 mg dolasetron orally plus 8 mg dexamethasone intravenously.The follow-up was for 24 h after surgery. RESULTS: In group A PONV was significantly more frequent (28%) compared to group B (12.0%).The incidence of vomiting was significantly lower in patients receiving dolasetron plus dexamethasone (0%) in comparison to patients receiving dolasetron (8.0%). Furthermore,patients satisfaction was significantly higher in group B compared to group A. About 6 or 7 patients need to be treated with additional dexamethasone instead of a placebo for one patient to benefit from this intervention (i.e. to stay free from PONV) who otherwise would have suffered from PONV. CONCLUSIONS: Combining oral dolasetron with intravenous dexamethasone further improves the antiemetic efficacy of dolasetron. With a number-needed-to-treat of about 6 the additional benefit might be considered clinically relevant.     

Randomized,double-blind comparison of different inspired oxygen fractions during general anaesthesia for Caesarean section

Background. The optimal inspired oxygen fraction FI_O2 for fetaloxygenation during general anaesthesia for Caesarean sectionis not known. Methods. We randomized patients having elective Caesarean sectionto receive one of the following: FI_O2 0.3, FI_N2O 0.7 and end-tidalsevoflurane 0.6% (Group 30, n=20); FI_O2 0.5, FI_N2O 0.5 and end-tidalsevoflurane 1.0% (Group 50, n=20), or FI_O2 1.0 and end-tidalsevoflurane 2.0% (Group 100, n=20) until delivery. Neonataloutcome was compared biochemically and clinically. Results. At delivery, for umbilical venous blood, mean PO₂ wasgreater in Group 100 (7.6 (SD 3.7) kPa) compared with both Group30 (4.0 (1.1) kPa, P<0.0001) and Group 50 (4.7 (0.9) kPa,P=0.002) and oxygen content was greater in Group 100 (17.2 (1.6)ml dl^–1) compared with both Group 30 (12.8 (3.6) ml dl^–1,P=0.0001) and Group 50 (13.8 (2.6) ml dl^–1, P=0.0001).For umbilical arterial blood, PO₂ was greater in Group 100 (3.2(0.4) kPa) compared with Group 30 (2.4 (0.7) kPa, P=0.003),and in Group 50 (2.9 (0.8) kPa) compared with Group 30 (2.4(0.7) kPa, P=0.04); oxygen content was greater in Group 100(10.8 (3.5) ml dl^–1) than in Group 30 (7.0 (3.0) ml dl^–1,P<0.01). Apgar scores, neonatal neurologic and adaptive capacityscores, and maternal arterial plasma concentrations of epinephrineand norepinephrine before induction and at delivery were similaramong groups. No patient reported intraoperative awareness. Conclusions. Use of FI_O2 1.0 during general anaesthesia forelective Caesarean section increased fetal oxygenation. Br J Anaesth 2002; 89: 556–61     

RETRACTED ARTICLE: Dolasetron, but not metoclopramide prevents nausea and vomiting in patients undergoing laparoscopic cholecystectomy

PURPOSE: Postoperative nausea and vomiting (PONV) is one of the most frequent complications of general anesthesia. The aim of the study was to compare the antiemetic efficacy of dolasetron and metoclopramide after inhalational or i.v. anesthesia (IVA). METHODS: In a randomized, placebo-controlled, double-blinded trial we evaluated the efficacy of 12.5 mg dolasetron i.v. and 20 mg metoclopramide (MCP) i.v. in preventing PONV in 387 patients (ASA I-III) undergoing laparoscopic cholecystectomy. Patients were allocated randomly to one of three main groups: Group D (n = 129) received 12.5 mg dolasetron i.v., Group MCP (n = 129) 20 mg MCP i.v., and Group C (n = 129) saline as placebo i.v. Using a multifactorial study design, one third of each main group (n = 43) was further randomized to receive either general anesthesia with desflurane, isoflurane or IVA with propofol and remifentanil. PONV, postoperative piritramide and droperidol consumption were documented. RESULTS: Independent from the anesthesia regimen chosen, dolasetron reduced PONV (19%) significantly compared to MCP (45%) and placebo (46%). Furthermore we could show a significant difference in the incidence of PONV between IVA (28%) and isoflurane (46%), but not in comparison to desflurane (36%). Patients receiving IVA had a higher postoperative piritramide consumption compared to the two other groups. CONCLUSIONS: The results of our study suggest that dolasetron was more effective than MCP and placebo in preventing PONV. This action is independent of the anesthetic technique used.     

Effect of obesity and site of surgery on perioperative lung volumes

Background. Although obese patients are thought to be susceptibleto postoperative pulmonary complications, there are only limiteddata on the relationship between obesity and lung volumes aftersurgery. We studied how surgery and obesity affect lung volumesmeasured by spirometry. Methods. We prospectively studied 161 patients having eitherbreast surgery (Group A, n=80) or lower abdominal laparotomy(Group B, n=81). Premedication and general anaesthesia werestandardized. Spirometry was measured with the patient supine,in a 30° head-up position. We measured vital capacity (VC),forced vital capacity, peak expiratory flow and forced expiratoryvolume in 1 s at preoperative assessment (baseline), after premedication(before induction of anaesthesia) and 10–20 min, 1 h and3 h after extubation. Results. Baseline spirometric values were all within the normalrange. All perioperative values decreased significantly withincreasing body mass index (BMI). The greatest reduction ofmean VC (expressed as percentage of baseline values) occurredafter extubation, and was more marked after laparotomy thanafter breast surgery (23 (SD 14)% vs 20 (14)%). Consideringpatients according to BMI (<25, 25–30, >30), VCdecreased after surgery by 12 (7)%, 24 (8)% and 40 (10)%, respectively.VC recovered more rapidly in Group A. Conclusion. Postoperative reduction in spirometric volumes wasrelated to BMI. Obesity had more effect on VC than the siteof surgery. Br J Anaesth 2004; 92: 202–7     

Effects of high intraoperative inspired oxygen on postoperative nausea and vomiting in gynecologic laparoscopic surgery

Study ObjectiveTo assess the efficacy of intraoperative inspired oxygen fractions (FIO₂) of 0.8 and 0.5 when compared with standard FIO₂ of 0.3 in the prevention of postoperative nausea and vomiting (PONV).DesignProspective, randomized, double-blinded, controlled study.SettingGeneral hospital, postanesthesia care unit (PACU), and gynecology floor room.Patients120 ASA physical status I and II women, aged 21 to 76 years, undergoing elective gynecologic laparoscopic surgery.InterventionsPatients were randomized to receive a gas mixture of 30% oxygen in air (FIO₂ = 0.3, Group G30), 50% oxygen in air (FIO₂ = 0.5, Group G50), or 80% oxygen in air (FIO₂ = 0.8, Group G80); there were 36 patients in each group. A standardized sevoflurane general anesthesia, postoperative pain management, and antiemetic regimen were used.MeasurementsFrequency of nausea, vomiting, and both was assessed for early (0 to two hrs) and late PONV (two to 24 hrs), along with use of rescue antiemetic, degree of nausea, and severity of pain.Main ResultsThere was no overall difference in the frequency of PONV at the early and late assessment periods among the three groups. G80 patients had significantly less vomiting than Group G30 at two hours, 3% (1/36) vs. 22% (8/36), respectively, P = 0.028. Nausea scores, rescue antiemetic use, pain scores, and opioid consumption did not differ among the groups.ConclusionHigh intraoperative FIO₂ of 0.8 and FIO₂ of 0.5 do not prevent PONV in patients without antiemetic prophylaxis. An intraoperative FIO₂ of 0.8 has a beneficial effect on early vomiting only.     

Randomized, placebo-controlled trial of combination antiemetic prophylaxis for day-case gynaecological laparoscopic surgery

In a randomized, double-blind trial, we compared i.v. ondansetron4 mg (control), i.v. ondansetron 4 mg and cyclizine50 mg (combination) and i.v. saline 0.9% (placebo), givenafter induction of standardized anaesthesia, for the preventionof nausea and vomiting (PONV) after day-case gynaecologicallaparoscopic surgery. Compared with placebo, fewer patientsin the control group vomited (9/20 versus 11/59, P=0.02) orneeded rescue antiemetic (7/20 versus 9/59, P=0.06) before discharge.Compared with the control, fewer patients in the combinationgroup (n=60) vomited (11/59 versus 2/60, P=0.01) or needed rescueantiemetic (29/59 versus 2/60, P=0.03) before discharge. Theincidence of vomiting in the combination group was less than5% overall. Compared with the control, the combination grouphad a significantly lower incidence (P=0.001) and severity (P<0.001)of nausea after discharge and more patients with no PONV atany time during the study (15/59 versus 27/60, P=0.03). Unlikethe placebo and control groups, no patient receiving combinationprophylaxis was admitted overnight for PONV management. Br J Anaesth 2000; 85: 678–82 ^* Corresponding author     

Patient well-being after general anaesthesia: a prospective, randomized, controlled multi-centre trial comparing intravenous and inhalation anaesthesia

Background. The aim of this study was to assess postoperativepatient well-being after total i.v. anaesthesia compared withinhalation anaesthesia by means of validated psychometric tests. Methods. With ethics committee approval, 305 patients undergoingminor elective gynaecologic or orthopaedic interventions wereassigned randomly to total i.v. anaesthesia using propofol orinhalation anaesthesia using sevoflurane. The primary outcomemeasurement was the actual mental state 90 min and 24 h afteranaesthesia assessed by a blinded observer using the AdjectiveMood Scale (AMS) and the State-Trait-Anxiety Inventory (STAI).Incidence of postoperative nausea and vomiting (PONV) and postoperativepain level were determined by Visual Analogue Scale (VAS) 90min and 24 h after anaesthesia (secondary outcome measurements).Patient satisfaction was evaluated using a VAS 24 h after anaesthesia. Results. The AMS and STAI scores were significantly better 90min after total i.v. anaesthesia compared with inhalation anaesthesia(P=0.02, P=0.05, respectively), but equal 24 h after both anaesthetictechniques (P=0.90, P=0.78, respectively); patient satisfactionwas comparable (P=0.26). Postoperative pain was comparable inboth groups 90 min and 24 h after anaesthesia (P=0.11, P=0.12,respectively). The incidence of postoperative nausea was reducedafter total i.v. compared with inhalation anaesthesia at 90min (7 vs 35%, P<0.001), and 24 h (33 vs 52%, P=0.001). Conclusion. Total i.v. anaesthesia improves early postoperativepatient well-being and reduces the incidence of PONV. Br J Anaesth 2003; 91: 631–7