Rusch 2002.

Study characteristics
Methods	Study design: randomized controlled trial Study grouping: 3 groups, monoprophylaxis
Participants	Baseline characteristics Placebo (group P) Assessed for eligibility (n): ‐ Enrolled (n): ‐ Randomized (n): 40 Received treatment (n): NA Analysed (n): 36 Age (mean ± SD, median (IQR), median (range)): 36 ± 9 Weight (mean ± SD, median (IQR), median (range)): 65 ± 11 BMI (mean ± SD, median (IQR), median (range)): NA ASA I/II/III/IV (n): NA/NA/0/0 Gender (female in %): 100 Non‐smoker (%): 52.78 History of PONV/motion sickness (%): 19.44 Type of general anaesthesia: balanced anaesthesia (isoflurane, N₂O, fentanyl) Duration of anaesthesia or surgery (in min; as mean or median): 103 Use of perioperative opioids (if yes, which?): 0.17 mg fentanyl intraoperative, 6 patients received piritramide as rescue analgesic Type of surgery: diagnostic or surgical gynaecological laparoscopy Droperidol (group D) Assessed for eligibility (n): ‐ Enrolled (n): ‐ Randomized (n): 40 Received treatment (n): NA Analysed (n): 33 Age (mean ± SD, median (IQR), median (range)): 36 ± 9 Weight (mean ± SD, median (IQR), median (range)): 62 ± 8 BMI (mean ± SD, median (IQR), median (range)): NA ASA I/II/III/IV (n): NA/NA/0/0 Gender (female in %): 100 Non‐smoker (%): 63.64 History of PONV/motion sickness (%): 24.24 Type of general anaesthesia: balanced anaesthesia (isoflurane, N₂O, fentanyl) Duration of anaesthesia or surgery (in min; as mean or median): 109 Use of perioperative opioids (if yes, which?): 0.19 mg fentanyl intraoperative, 6 patients received piritramide as rescue analgesic Type of surgery: diagnostic or surgical gynaecological laparoscopy Metoclopramide (group M) Assessed for eligibility (n): ‐ Enrolled (n): ‐ Randomized (n): 40 Received treatment (n): NA Analysed (n): 33 Age (mean ± SD, median (IQR), median (range)): 34 ± 9 Weight (mean ± SD, median (IQR), median (range)): 71 ± 13 BMI (mean ± SD, median (IQR), median (range)): NA ASA I/II/III/IV (n): NA/NA/0/0 Gender (female in %): 100 Non‐smoker (%): 33.33 History of PONV/motion sickness (%): 36.36 Type of general anaesthesia: balanced anaesthesia (isoflurane, N₂O, fentanyl) Duration of anaesthesia or surgery (in min; as mean or median): 99 Use of perioperative opioids (if yes, which?): 0.17 mg fentanyl intraoperative, 5 patients received piritramide as rescue analgesic Type of surgery: diagnostic or surgical gynaecological laparoscopy Included criteria: women 18 to 50 years of age, ASA I or II, scheduled for elective diagnostic or surgical gynaecological laparoscopy, additional inclusion criteria for Group X: risk for postoperative vomiting > 25% (according to Apfel's risk score), duration of anaesthesia at least 1 hour Excluded criteria: pregnancy, breastfeeding, known allergy to used drugs, intake of antiemetic drugs during the last 24 hours, gastrointestinal infection in the past 2 weeks, extreme underweight or overweight (30% of the Broca‐Index), difficulties in communication or other reason for giving a non‐valid consent Pretreatment: baseline characteristics (age, weight, ASA): no. Potential effect modifiers (gender, duration of anaesthesia, history of PONV/motion sickness, perioperative opioids): no; (non‐smoker): yes
Interventions	Intervention characteristics Placebo (group P) Dose: NaCl Time point of administration: 20 minutes before end of surgery Route of administration: IV Rescue antiemetics (if yes, which?): (1) dimenhydrinate 62.5 mg; (2) metoclopramide 10 mg; (3) droperidol 1.25 mg Droperidol (group D) Dose: 2.5 mg Time point of administration: 20 minutes before end of surgery Route of administration: IV Rescue antiemetics (if yes, which?): (1) dimenhydrinate 62.5 mg; (2) metoclopramide 10 mg; (3) droperidol 1.25 mg Metoclopramide (group M) Dose: 10 mg Time point of administration: 20 minutes before end of surgery Route of administration: IV Rescue antiemetics (if yes, which?): (1) dimenhydrinate 62.5 mg; (2) metoclopramide 10 mg; (3) droperidol 1.25 mg
Outcomes	Vomiting (0 to 24 hours) Outcome type: dichotomous outcome Nausea (0 to 24 hours) Outcome type: dichotomous outcome Extrapyramidal symptoms (0 to 24 hours) Outcome type: dichotomous outcome Headache (0 to 24 hours) Outcome type: dichotomous outcome Adverse events (general notes in the publication, 24 hours' observation) Outcome type: general notes on side effects
Identification	Sponsorship source: NA Country: Germany Setting: inpatient, single‐centre Author's name: Dirk Rüsch Institution: Klinik für Anästhesiologie und Operative Intensivmedizin der Christian‐Albrechts‐Universität zu Kiel Email: ruesch@anaesthesie.uni‐kiel.de Address: Klinik für Anästhesiologie und Operative Intensivmedizin der Christian‐Albrechts‐Universität zu Kiel, Schwanenweg 21, 24105 Kiel Duration of study: NA Language: German (2 German reviewers) Study's primary outcome: incidence of PONV Trial registry number: NA
Notes	Two studies (only study part I with 3 groups eligible)
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "Zuordnung gemäß Randomisierungsliste" Judgement comment: random number table
Allocation concealment (selection bias)	Unclear risk	Judgement comment: no statement
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Judgement comment: insufficient information on blinding ("untersucherblind")
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Quote: "postoperativ wurden untersucherblind folgende Parameter erfasst" Judgement comment: outcome assessors were blinded
Incomplete outcome data (attrition bias) All outcomes	Low risk	Quote: "von den ursprünglich 40 Patientinnen jeder Studiengruppe des ersten Teils der Untersuchung sowie von den ursprünglich 50 Patientinnen des zweiten Teils der Untersuchung wurden jeweils 33 (Gruppe D und M) bzw. 36 (Gruppe P) bzw. 43 (Gruppe X) Patientinnen in die Auswertung einbezogen. Gründe für den Ausschluss einiger Patientinnen von der Auswertung waren: Wechsel des Operationsverfahrens auf eine offene Laparotomie, Abweichen der Narkoseführung von dem im Studienprotokoll vorgesehenen Prozedere, unvollständig oder fehler"
Selective reporting (reporting bias)	Unclear risk	Judgement comment: no reference to a study protocol or trial registry number reported
Other bias	High risk	Quote: "die Studiengruppen waren bezüglich ihrer biometrischen Daten vergleichbar (Tab. 1). Unterschiede existierten jedoch zwischen den Gruppen bezüglich der PONV‐relevanten Risikofaktoren Nichtraucherstatus und Reisekrankheit bzw. PONV in der Anamnese. Betrachtet man allerdings die Scores zur Bestimmung der Wahrscheinlichkeit für postoperatives Erbrechen [2] bzw. für PONV [9], welche beide zuvor genannten Risikofaktoren miteinbeziehen, so zeigt sich, dass die Gruppen durchaus als homogen hinsichtlich ihres PONV‐Risikos zu betrachten sind" Judgement comment: baseline characteristics (age, weight, ASA): no. Potential effect modifiers (gender, duration of anaesthesia, history of PONV/motion sickness, perioperative opioids): no; (non‐smoker): yes