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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.
1,463 questions in 125 reviews · Anaesthesia
current versionsNo 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.
| Question | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Acetaminophen vs control or placebo medications Chronic headache · adults undergoing brain surgery Pharmacological interventions for the prevention of acute postoperative pain in adults following brain surgery (2019) · Cochrane | no estimate extracted | NR | No studies |
Acetaminophen vs control or placebo medications Length of critical care stay (hours) · adults undergoing brain surgery Pharmacological interventions for the prevention of acute postoperative pain in adults following brain surgery (2019) · Cochrane | no estimate extracted | 1 study · 131 participants | Very low |
Acetaminophen vs control or placebo medications Length of hospital stay (hours) · adults undergoing brain surgery Pharmacological interventions for the prevention of acute postoperative pain in adults following brain surgery (2019) · Cochrane | no estimate extracted | 2 studies · 335 participants | Moderate |
Acetaminophen vs control or placebo medications Adverse events · adults undergoing brain surgery Pharmacological interventions for the prevention of acute postoperative pain in adults following brain surgery (2019) · Cochrane | no estimate extracted | NR | No studies |
Scalp infiltration vs control or placebo intervention Acute postoperative pain 0 to 6 hours (Score 0 to 10, VAS or NRS Scale) · adults undergoing brain surgery Pharmacological interventions for the prevention of acute postoperative pain in adults following brain surgery (2019) · Cochrane | no estimate extracted | 9 studies · 475 participants | Moderate |
Scalp infiltration vs control or placebo intervention Acute postoperative pain at 12 hours (Score 0 to 10, VAS or NRS Scale) · adults undergoing brain surgery Pharmacological interventions for the prevention of acute postoperative pain in adults following brain surgery (2019) · Cochrane | no estimate extracted | 7 studies · 309 participants | Low |
Scalp infiltration vs control or placebo intervention Acute postoperative pain at 24 hours (Score 0 to 10, VAS or NRS Scale) · adults undergoing brain surgery Pharmacological interventions for the prevention of acute postoperative pain in adults following brain surgery (2019) · Cochrane | no estimate extracted | 6 studies · 260 participants | Moderate |
Scalp infiltration vs control or placebo intervention Acute postoperative pain at 48 hours (score 0 to 10, VAS or NRS scale) · adults undergoing brain surgery Pharmacological interventions for the prevention of acute postoperative pain in adults following brain surgery (2019) · Cochrane | no estimate extracted | 3 studies · 128 participants | Moderate |
Scalp infiltration vs control or placebo intervention Additional analgesia requirements 0 to 24 hours (milligrams) · adults undergoing brain surgery Pharmacological interventions for the prevention of acute postoperative pain in adults following brain surgery (2019) · Cochrane | no estimate extracted | 6 studies · 345 participants | Very low |
Nonsteroidal anti‐inflammatory drugs (NSAIDs) vs control or placebo medications Additional analgesia requirements 0 to 24 hours (Milligrams) · adults undergoing brain surgery Pharmacological interventions for the prevention of acute postoperative pain in adults following brain surgery (2019) · Cochrane | no estimate extracted | 4 studies · 265 participants | Low |
Scalp infiltration vs control or placebo intervention Analgesic Success · adults undergoing brain surgery Pharmacological interventions for the prevention of acute postoperative pain in adults following brain surgery (2019) · Cochrane | no estimate extracted | 1 study · 49 participants | Very low |
Scalp infiltration vs control or placebo intervention Sedation · adults undergoing brain surgery Pharmacological interventions for the prevention of acute postoperative pain in adults following brain surgery (2019) · Cochrane | no estimate extracted | NR | No studies |
Scalp infiltration vs control or placebo intervention Chronic headache · adults undergoing brain surgery Pharmacological interventions for the prevention of acute postoperative pain in adults following brain surgery (2019) · Cochrane | no estimate extracted | NR | No studies |
Scalp infiltration vs control or placebo intervention Length of critical care stay (hours) · adults undergoing brain surgery Pharmacological interventions for the prevention of acute postoperative pain in adults following brain surgery (2019) · Cochrane | no estimate extracted | NR | No studies |
Scalp infiltration vs control or placebo intervention Length of hospital stay (hours) · adults undergoing brain surgery Pharmacological interventions for the prevention of acute postoperative pain in adults following brain surgery (2019) · Cochrane | no estimate extracted | NR | No studies |
Scalp infiltration vs control or placebo intervention Adverse event nausea and vomiting (0 to 24 hours) · adults undergoing brain surgery Pharmacological interventions for the prevention of acute postoperative pain in adults following brain surgery (2019) · Cochrane | no estimate extracted | 4 studies · 318 participants | Low |
Scalp block vs control or placebo intervention Acute postoperative pain 0 to 6 hours (Score 0 to 10, VAS or NRS Scale) · adults undergoing brain surgery Pharmacological interventions for the prevention of acute postoperative pain in adults following brain surgery (2019) · Cochrane | no estimate extracted | 10 studies · 414 participants | Low |
Scalp block vs control or placebo intervention Acute postoperative pain at 12 hours (Score 0 to 10, VAS or NRS Scale) · adults undergoing brain surgery Pharmacological interventions for the prevention of acute postoperative pain in adults following brain surgery (2019) · Cochrane | no estimate extracted | 8 studies · 294 participants | Low |
Scalp block vs control or placebo intervention Acute postoperative pain at 24 hours (Score 0 to 10, VAS or NRS Scale) · adults undergoing brain surgery Pharmacological interventions for the prevention of acute postoperative pain in adults following brain surgery (2019) · Cochrane | no estimate extracted | 9 studies · 433 participants | Low |
Scalp block vs control or placebo intervention Acute postoperative pain at 48 hours (Score 0 to 10, VAS or NRS Scale) · adults undergoing brain surgery Pharmacological interventions for the prevention of acute postoperative pain in adults following brain surgery (2019) · Cochrane | no estimate extracted | 4 studies · 135 participants | Very low |
Nonsteroidal anti‐inflammatory drugs (NSAIDs) vs control or placebo medications Analgesic Success · adults undergoing brain surgery Pharmacological interventions for the prevention of acute postoperative pain in adults following brain surgery (2019) · Cochrane | no estimate extracted | NR | Very low |
Scalp block vs control or placebo intervention Additional analgesia requirements 0 to 24 hours · adults undergoing brain surgery Pharmacological interventions for the prevention of acute postoperative pain in adults following brain surgery (2019) · Cochrane | no estimate extracted | 7 studies · 314 participants | Low |
Scalp block vs control or placebo intervention Analgesic success · adults undergoing brain surgery Pharmacological interventions for the prevention of acute postoperative pain in adults following brain surgery (2019) · Cochrane | no estimate extracted | 1 study · 40 participants | Very low |
Scalp block vs control or placebo intervention Sedation · adults undergoing brain surgery Pharmacological interventions for the prevention of acute postoperative pain in adults following brain surgery (2019) · Cochrane | no estimate extracted | NR | No studies |
Scalp block vs control or placebo intervention Chronic headache · adults undergoing brain surgery Pharmacological interventions for the prevention of acute postoperative pain in adults following brain surgery (2019) · Cochrane | no estimate extracted | NR | No studies |
Scalp block vs control or placebo intervention Length of critical care stay (hours) · adults undergoing brain surgery Pharmacological interventions for the prevention of acute postoperative pain in adults following brain surgery (2019) · Cochrane | no estimate extracted | NR | No studies |
Scalp block vs control or placebo intervention Length of hospital stay (hours) · adults undergoing brain surgery Pharmacological interventions for the prevention of acute postoperative pain in adults following brain surgery (2019) · Cochrane | no estimate extracted | NR | No studies |
Scalp block vs control or placebo intervention Adverse event nausea and vomiting (0 to 24 hours) · adults undergoing brain surgery Pharmacological interventions for the prevention of acute postoperative pain in adults following brain surgery (2019) · Cochrane | no estimate extracted | 4 studies · 165 participants | Very low |
Nonsteroidal anti‐inflammatory drugs (NSAIDs) vs control or placebo medications Sedation · adults undergoing brain surgery Pharmacological interventions for the prevention of acute postoperative pain in adults following brain surgery (2019) · Cochrane | no estimate extracted | NR | No studies |
Nonsteroidal anti‐inflammatory drugs (NSAIDs) vs control or placebo medications Chronic Headache · adults undergoing brain surgery Pharmacological interventions for the prevention of acute postoperative pain in adults following brain surgery (2019) · Cochrane | no estimate extracted | NR | No studies |
Nonsteroidal anti‐inflammatory drugs (NSAIDs) vs control or placebo medications Length of critical care stay (hours) · adults undergoing brain surgery Pharmacological interventions for the prevention of acute postoperative pain in adults following brain surgery (2019) · Cochrane | no estimate extracted | NR | No studies |
Supplemental IV crystalloid vs control IV crystalloid volume Risk of PON, defined as the presence of subjective nausea, reported dichotomously or based on a study‐defined dichotomous threshold on a continuous scale such as a VAS · participants aged 6 months or older undergoing surgical procedures under general anaesthesia Supplemental perioperative intravenous crystalloids for postoperative nausea and vomiting (2019) · Cochrane | RR 0.62 [0.51, 0.75] | 18 studies · 1766 participants | Moderate |
Supplemental IV crystalloid vs control IV crystalloid volume Risk of POV, reported dichotomously by any discrete episodes of vomiting · participants aged 6 months or older undergoing surgical procedures under general anaesthesia Supplemental perioperative intravenous crystalloids for postoperative nausea and vomiting (2019) · Cochrane | RR 0.5 [0.4, 0.63] | 20 studies · 1970 participants | Moderate |
Supplemental IV crystalloid vs control IV crystalloid volume Risk of requiring pharmacologic treatment for PONV, reported dichotomously as the use of any medication intended to treat nausea or vomiting during the postoperative period · participants aged 6 months or older undergoing surgical procedures under general anaesthesia Supplemental perioperative intravenous crystalloids for postoperative nausea and vomiting (2019) · Cochrane | RR 0.62 [0.51, 0.76] | 23 studies · 2416 participants | Moderate |
Supplemental IV crystalloid vs control IV crystalloid volume Risk of unintended postoperative admission to hospital, reported dichotomously as admission to an inpatient unit of a participant after an intended ambulatory surgical procedure · participants aged 6 months or older undergoing surgical procedures under general anaesthesia Supplemental perioperative intravenous crystalloids for postoperative nausea and vomiting (2019) · Cochrane | RR 1.05 [0.77, 1.43] | 3 studies · 235 participants | Low |
Supplemental IV crystalloid vs control IV crystalloid volume Risk of suffering a serious adverse event, reported dichotomously as the occurrence of any of: admission to high‐dependency unit, postoperative cardiac or respiratory complication, or death · participants aged 6 months or older undergoing surgical procedures under general anaesthesia Supplemental perioperative intravenous crystalloids for postoperative nausea and vomiting (2019) · Cochrane | no estimate extracted | NR | No studies |
Intervention NR Postoperative pain at rest (VAS 0 to 100 mm, NRS 0 to 10) (2 hours) · adult participants undergoing knee surgery (arthroscopic knee surgery or total knee replacement) Adductor canal blocks for postoperative pain treatment in adults undergoing knee surgery (2019) · Cochrane | no estimate extracted | 4 studies · 208 participants | Low |
Intervention NR Postoperative pain during movement (VAS 0 to 100 mm, NRS 0 to 10) (24 hours) · adult participants undergoing knee surgery (arthroscopic knee surgery or total knee replacement) Adductor canal blocks for postoperative pain treatment in adults undergoing knee surgery (2019) · Cochrane | no estimate extracted | 9 studies · 576 participants | Very low |
Intervention NR Postoperative nausea (24 hours) · adult participants undergoing knee surgery (arthroscopic knee surgery or total knee replacement) Adductor canal blocks for postoperative pain treatment in adults undergoing knee surgery (2019) · Cochrane | no estimate extracted | 2 studies · 138 participants | Low |
Intervention NR Accidental falls during postoperative care (24 hours) · adult participants undergoing knee surgery (arthroscopic knee surgery or total knee replacement) Adductor canal blocks for postoperative pain treatment in adults undergoing knee surgery (2019) · Cochrane | no estimate extracted | 3 studies · 172 participants | Low |
Intervention NR Postoperative pain at rest (VAS 0 to 100 mm, NRS 0 to 10) (24 hours) · adult participants undergoing knee surgery (arthroscopic knee surgery or total knee replacement) Adductor canal blocks for postoperative pain treatment in adults undergoing knee surgery (2019) · Cochrane | no estimate extracted | 6 studies · 272 participants | Low |
Intervention NR Postoperative pain during movement (VAS 0 to 100 mm, NRS 0 to 10) (2 hours) · adult participants undergoing knee surgery (arthroscopic knee surgery or total knee replacement) Adductor canal blocks for postoperative pain treatment in adults undergoing knee surgery (2019) · Cochrane | no estimate extracted | 3 studies · 160 participants | Very low |
Intervention NR Postoperative pain during movement (VAS 0 to 100 mm, NRS 0 to 10) (24 hours) · adult participants undergoing knee surgery (arthroscopic knee surgery or total knee replacement) Adductor canal blocks for postoperative pain treatment in adults undergoing knee surgery (2019) · Cochrane | no estimate extracted | 4 studies · 184 participants | Low |
Intervention NR Postoperative nausea (24 hours) · adult participants undergoing knee surgery (arthroscopic knee surgery or total knee replacement) Adductor canal blocks for postoperative pain treatment in adults undergoing knee surgery (2019) · Cochrane | RR 1.91 [0.48, 7.58] | 3 studies · 121 participants | Low |
Intervention NR Accidental falls during postoperative care (24 hours) · adult participants undergoing knee surgery (arthroscopic knee surgery or total knee replacement) Adductor canal blocks for postoperative pain treatment in adults undergoing knee surgery (2019) · Cochrane | no estimate extracted | 1 study · 48 participants | Low |
Intervention NR Postoperative pain at rest (VAS 0 to 100 mm, NRS 0 to 10) (2 hours) · adult participants undergoing knee surgery (arthroscopic knee surgery or total knee replacement) Adductor canal blocks for postoperative pain treatment in adults undergoing knee surgery (2019) · Cochrane | no estimate extracted | 5 studies · 298 participants | Low |
Intervention NR Postoperative pain at rest (VAS 0 to 100 mm, NRS 0 to 10) (24 hours) · adult participants undergoing knee surgery (arthroscopic knee surgery or total knee replacement) Adductor canal blocks for postoperative pain treatment in adults undergoing knee surgery (2019) · Cochrane | no estimate extracted | 12 studies · 868 participants | High |
Intervention NR Postoperative pain during movement (VAS 0 to 100 mm, NRS 0 to 10) (2 hours) · adult participants undergoing knee surgery (arthroscopic knee surgery or total knee replacement) Adductor canal blocks for postoperative pain treatment in adults undergoing knee surgery (2019) · Cochrane | no estimate extracted | 2 studies · 88 participants | Very low |
Perioperative restrictive fluid therapy vs goal‐directed fluid therapy Major complications (during longest · adults receiving intravenous fluids while undergoing major non‐cardiac surgery Perioperative restrictive versus goal‐directed fluid therapy for adults undergoing major non‐cardiac surgery (2019) · Cochrane | RR 1.61 [0.78, 3.34] | 5 studies · 484 participants | Very low |
Perioperative restrictive fluid therapy vs goal‐directed fluid therapy All‐cause mortality (during longest · adults receiving intravenous fluids while undergoing major non‐cardiac surgery Perioperative restrictive versus goal‐directed fluid therapy for adults undergoing major non‐cardiac surgery (2019) · Cochrane | RD 0.03 [0, 0.06] | 6 studies · 544 participants | Very low |