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Search review questions

Each row is one question a systematic review asked: who, what, compared with what, and which outcome, with the effect it found and how certain that is. Words match anywhere in the field.

Limit to evidence status or GRADE (optional)

1,463 questions in 125 reviews · Anaesthesia

current versions
No studies 197 · 13.5%Ungraded 203 · 13.9%Very low 307 · 21%Low 441 · 30.1%Moderate 245 · 16.7%High 70 · 4.8%

Ungraded means an effect was reported without a GRADE rating; it is not a gap. No studies means the review found nothing to answer the question. The six categories are a display order, not a score.

QuestionEffectEvidenceStatus / GRADE
Intervention NR
Anticholinergics · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extractedNRNo studies
Intervention NR
Scopolamine (8 RCTs; 683 participants) · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extracted8 studies · 683 participantsLow
Intervention NR
Comparator · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extractedNRNo studies
Intervention NR
Placebo · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extractedNRNo studies
Intervention NR
Placebo · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extractedNRNo studies
Intervention NR
Total studies: 18 RCTs Total participants: 4440 Number of treatments: 13 Geometry of the network** · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extracted18 studies · 4440 participantsUngraded
Intervention NR
Dolasetron (0 RCTs; 0 participants) · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extracted0 studies · 0 participantsUngraded
Intervention NR
Granisetron (0 RCTs; 0 participants) · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extracted0 studies · 0 participantsUngraded
Intervention NR
Ondansetron (1 RCT; 60 participants) · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extracted1 study · 60 participantsLow
Intervention NR
Palonosetron (1 RCT; 546 participants) · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extracted1 study · 546 participantsVery low
Intervention NR
Ramosetron (no direct evidence, indirect evidence only) · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extractedNRVery low
Intervention NR
Tropisetron (1 RCT; 385 participants) · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extracted1 study · 385 participantsVery low
Intervention NR
D2 receptor antagonists · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extracted2 participantsUngraded
Intervention NR
Amisulpride (0 RCTs; 0 participants) · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extracted0 studies · 0 participantsUngraded
Intervention NR
Granisetron (16 RCTs; 2270 participants) · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extracted16 studies · 2270 participantsHigh
Intervention NR
Total studies: 28 RCTs Total participants: 10,766 Number of treatments: 22 Geometry of the network** · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extracted28 studies · 10766 participantsUngraded
Intervention NR
Droperidol (3 RCTs; 303 participants) · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extracted3 studies · 303 participantsLow
Intervention NR
Haloperidol (4 RCTs; 338 participants) · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extracted4 studies · 338 participantsLow
Intervention NR
Metoclopramide (0 RCTs; 0 participants) · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extracted0 studies · 0 participantsUngraded
Intervention NR
Perphenazine (0 RCTs; 0 participants) · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extracted0 studies · 0 participantsUngraded
Intervention NR
NK1 receptor antagonists · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extracted1 participantsUngraded
Intervention NR
Aprepitant (nNo direct evidence, indirect evidence only) · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extractedNRVery low
Intervention NR
Casopitant (0 RCTs; 0 participants) · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extracted0 studies · 0 participantsUngraded
Intervention NR
Fosaprepitant (0 RCTs; 0 participants) · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extracted0 studies · 0 participantsUngraded
Intervention NR
Rolapitant (0 RCTs; 0 participants) · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extracted0 studies · 0 participantsUngraded
Intervention NR
Corticosteroids · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extractedNRNo studies
Intervention NR
Dolasetron (3 RCTs; 1448 participants) · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extracted3 studies · 1448 participantsLow
Intervention NR
Dexamethasone (1 RCT; 149 participants) · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extracted1 study · 149 participantsVery low
Intervention NR
Methylprednisolone (0 RCTs; 0 participants) · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extracted0 studies · 0 participantsUngraded
Intervention NR
Antihistamines · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extractedNRNo studies
Intervention NR
Dimenhydrinate (0 RCTs; 0 participants) · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extracted0 studies · 0 participantsUngraded
Intervention NR
Meclizine (0 RCTs; 0 participants) · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extracted0 studies · 0 participantsUngraded
Intervention NR
Promethazine (0 RCTs; 0 participants) · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extracted0 studies · 0 participantsUngraded
Intervention NR
Anticholinergics · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extractedNRNo studies
Intervention NR
Scopolamine (0 RCTs; 0 participants) · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extracted0 studies · 0 participantsUngraded
Intervention NR
Comparator · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extractedNRNo studies
Intervention NR
Placebo · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extractedNRNo studies
Intervention NR
Granisetron (2 RCTs; 401 participants) · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extracted2 studies · 401 participantsVery low
Intervention NR
Ondansetron (3 RCTs; 833 participants) · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extracted3 studies · 833 participantsVery low
Intervention NR
Palonosetron (3 RCTs; 1319 participants) · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extracted3 studies · 1319 participantsVery low
Intervention NR
Ramosetron (1 RCT; 236 participants) · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extracted1 study · 236 participantsVery low
Intervention NR
Tropisetron (2 RCTs; 727 participants) · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extracted2 studies · 727 participantsVery low
Intervention NR
D2 receptor antagonists · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extracted2 participantsUngraded
Intervention NR
Amisulpride (2 RCTs; 904 participants) · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extracted2 studies · 904 participantsLow
Intervention NR
Droperidol (2 RCTs; 304 participants) · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extracted2 studies · 304 participantsLow
Intervention NR
Ondansetron (77 RCTs; 14,435 participants) · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extracted77 studies · 14435 participantsHigh
Intervention NR
Haloperidol (0 RCTs; 0 participants) · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extracted0 studies · 0 participantsUngraded
Intervention NR
Metoclopramide (0 RCTs; 0 participants) · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extracted0 studies · 0 participantsUngraded
Intervention NR
Perphenazine (0 RCTs; 0 participants) · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extracted0 studies · 0 participantsUngraded
Intervention NR
NK1 receptor antagonists · adults undergoing any type of surgery under general anaesthesia Interventions: antiemetic drugs (monoprophylaxis and…
Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network… (2020) · Cochrane
no estimate extracted1 participantsUngraded