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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 |
|---|---|---|---|
Peppermint vs placebo Nausea duration (nausea‐free at end of treatment) Measured by participant self‐report or medical or nursing observation · adults and children having any type of surgical procedure under general anaesthesia, regional anaesthesia or sedation,… Aromatherapy for treatment of postoperative nausea and vomiting (2018) · Cochrane | no estimate extracted | NR | No studies |
Peppermint vs placebo Use of rescue antiemetics · adults and children having any type of surgical procedure under general anaesthesia, regional anaesthesia or sedation,… Aromatherapy for treatment of postoperative nausea and vomiting (2018) · Cochrane | no estimate extracted | NR | No studies |
Peppermint vs placebo Adverse events (common reactions to aromatherapy include skin rashes, dyspnoea, headache, cardiac arrhythmias, hypotension, hypertension or dizziness) · adults and children having any type of surgical procedure under general anaesthesia, regional anaesthesia or sedation,… Aromatherapy for treatment of postoperative nausea and vomiting (2018) · Cochrane | no estimate extracted | NR | No studies |
Perioperative alcohol cessation intervention vs treatment Postoperative complications after perioperative intervention (e.g. wound‐related complications, secondary surgery, cardiopulmonary complications, admission to intensive care) defined by need for treatment · adult surgical patients consuming 3 or more units of alcohol per day Perioperative alcohol cessation intervention for postoperative complications (2018) · Cochrane | RR 0.62 [0.4, 0.96] | 3 studies · 122 participants | Moderate |
Perioperative alcohol cessation intervention vs treatment In‐hospital and 30‐day mortality · adult surgical patients consuming 3 or more units of alcohol per day Perioperative alcohol cessation intervention for postoperative complications (2018) · Cochrane | RR 0.47 [0.07, 2.96] | 3 studies · 122 participants | Low |
Perioperative alcohol cessation intervention vs treatment Successful quitters (number of abstainers) at the end of the programme (with or without validation by interview, breath test, or alcohol markers) · adult surgical patients consuming 3 or more units of alcohol per day Perioperative alcohol cessation intervention for postoperative complications (2018) · Cochrane | RR 8.22 [1.67, 40.44] | 3 studies · 140 participants | Moderate |
Intravenous (IV) lidocaine vs placebo or no treatment Pain (VAS 0 to 10 cm, 0 to 100 mm, NRS 0 to 10) · adult patients undergoing any elective or urgent surgical procedure under general anaesthesia Continuous intravenous perioperative lidocaine infusion for postoperative pain and recovery in adults (2018) · Cochrane | no estimate extracted | 29 studies · 1656 participants | Very low |
Intravenous (IV) lidocaine vs thoracic epidural analgesia (TEA) Postoperative opioid consumption, 'overall' (MEQ, mg) · adult patients undergoing any elective or urgent surgical procedure under general anaesthesia Continuous intravenous perioperative lidocaine infusion for postoperative pain and recovery in adults (2018) · Cochrane | no estimate extracted | 0 studies · 0 participants | Ungraded |
Intravenous (IV) lidocaine vs placebo or no treatment Gastrointestinal recovery · adult patients undergoing any elective or urgent surgical procedure under general anaesthesia Continuous intravenous perioperative lidocaine infusion for postoperative pain and recovery in adults (2018) · Cochrane | RR 0.37 [0.15, 0.87] | 4 studies · 273 participants | Very low |
Intravenous (IV) lidocaine vs placebo or no treatment Adverse events (e.g. the number of participants that died, or had arrhythmias, other heart rate disorders, or showed any signs of lidocaine toxicity) · adult patients undergoing any elective or urgent surgical procedure under general anaesthesia Continuous intravenous perioperative lidocaine infusion for postoperative pain and recovery in adults (2018) · Cochrane | no estimate extracted | NR | Very low |
Intravenous (IV) lidocaine vs placebo or no treatment Postoperative nausea, 'overall' (0 to 24 h, to 48 h, to 72 h) · adult patients undergoing any elective or urgent surgical procedure under general anaesthesia Continuous intravenous perioperative lidocaine infusion for postoperative pain and recovery in adults (2018) · Cochrane | RR 0.78 [0.67, 0.91] | 35 studies · 1903 participants | Very low |
Intravenous (IV) lidocaine vs placebo or no treatment Postoperative opioid consumption, 'overall' (MEQ, mg) · adult patients undergoing any elective or urgent surgical procedure under general anaesthesia Continuous intravenous perioperative lidocaine infusion for postoperative pain and recovery in adults (2018) · Cochrane | no estimate extracted | 40 studies · 2201 participants | Very low |
Intravenous (IV) lidocaine vs thoracic epidural analgesia (TEA) Pain (VAS 0 to 10 cm, 0 to 100 mm, NRS 0 to 10 · adult patients undergoing any elective or urgent surgical procedure under general anaesthesia Continuous intravenous perioperative lidocaine infusion for postoperative pain and recovery in adults (2018) · Cochrane | no estimate extracted | 0 studies · 0 participants | Ungraded |
Intravenous (IV) lidocaine vs thoracic epidural analgesia (TEA) Gastrointestinal recovery · adult patients undergoing any elective or urgent surgical procedure under general anaesthesia Continuous intravenous perioperative lidocaine infusion for postoperative pain and recovery in adults (2018) · Cochrane | no estimate extracted | 1 study · 60 participants | Very low |
Intravenous (IV) lidocaine vs thoracic epidural analgesia (TEA) Adverse events (e.g. the number of participants that died, or had arrhythmias, other heart rate disorders, or showed any signs of lidocaine toxicity) · adult patients undergoing any elective or urgent surgical procedure under general anaesthesia Continuous intravenous perioperative lidocaine infusion for postoperative pain and recovery in adults (2018) · Cochrane | no estimate extracted | NR | Very low |
Intravenous (IV) lidocaine vs thoracic epidural analgesia (TEA) Postoperative nausea, 'overall' (0 to 24 h, to 48 h, to 72 h) · adult patients undergoing any elective or urgent surgical procedure under general anaesthesia Continuous intravenous perioperative lidocaine infusion for postoperative pain and recovery in adults (2018) · Cochrane | no estimate extracted | 1 study · 60 participants | Very low |
Intervention NR Intraoperative pain (reported dichotomous) · adults (aged ≥ 18 years) undergoing ophthalmic surgery under local anaesthetic eye blocks. Use of hyaluronidase as an adjunct to local anaesthetic eye blocks to reduce intraoperative pain in adults (2018) · Cochrane | RR 0.83 [0.48, 1.42] | 4 studies · 289 participants | Low |
Intervention NR Intraoperative pain (reported continuous) · adults (aged ≥ 18 years) undergoing ophthalmic surgery under local anaesthetic eye blocks. Use of hyaluronidase as an adjunct to local anaesthetic eye blocks to reduce intraoperative pain in adults (2018) · Cochrane | no estimate extracted | 3 studies · 211 participants | Low |
Intervention NR Incidence of harm · adults (aged ≥ 18 years) undergoing ophthalmic surgery under local anaesthetic eye blocks. Use of hyaluronidase as an adjunct to local anaesthetic eye blocks to reduce intraoperative pain in adults (2018) · Cochrane | no estimate extracted | 0 studies · 0 participants | Ungraded |
Intervention NR Participant satisfaction · adults (aged ≥ 18 years) undergoing ophthalmic surgery under local anaesthetic eye blocks. Use of hyaluronidase as an adjunct to local anaesthetic eye blocks to reduce intraoperative pain in adults (2018) · Cochrane | no estimate extracted | 2 studies · 122 participants | Moderate |
Intervention NR Surgical satisfaction · adults (aged ≥ 18 years) undergoing ophthalmic surgery under local anaesthetic eye blocks. Use of hyaluronidase as an adjunct to local anaesthetic eye blocks to reduce intraoperative pain in adults (2018) · Cochrane | no estimate extracted | 3 studies · 141 participants | Moderate |
Intervention NR Economic outcomes or cost calculations · adults (aged ≥ 18 years) undergoing ophthalmic surgery under local anaesthetic eye blocks. Use of hyaluronidase as an adjunct to local anaesthetic eye blocks to reduce intraoperative pain in adults (2018) · Cochrane | no estimate extracted | 0 studies · 0 participants | Ungraded |
Epidural analgesia vs intravenous patient‐controlled analgesia Pain score at rest · adults undergoing intra‐abdominal surgery (including hysterectomies, radical prostatectomies, Caesarean sections,… Epidural analgesia versus patient‐controlled intravenous analgesia for pain following intra‐abdominal… (2018) · Cochrane | no estimate extracted | 7 studies · 384 participants | Moderate |
Epidural analgesia vs intravenous patient‐controlled analgesia Pain score on movement · adults undergoing intra‐abdominal surgery (including hysterectomies, radical prostatectomies, Caesarean sections,… Epidural analgesia versus patient‐controlled intravenous analgesia for pain following intra‐abdominal… (2018) · Cochrane | no estimate extracted | 2 studies · 80 participants | Low |
Epidural analgesia vs intravenous patient‐controlled analgesia All‐cause mortality rate at 30 days · adults undergoing intra‐abdominal surgery (including hysterectomies, radical prostatectomies, Caesarean sections,… Epidural analgesia versus patient‐controlled intravenous analgesia for pain following intra‐abdominal… (2018) · Cochrane | RR 3.37 [0.72, 15.88] | 9 studies · 560 participants | Low |
Epidural analgesia vs intravenous patient‐controlled analgesia Failure of analgesic technique requiring alternative approach (assessed at any time) · adults undergoing intra‐abdominal surgery (including hysterectomies, radical prostatectomies, Caesarean sections,… Epidural analgesia versus patient‐controlled intravenous analgesia for pain following intra‐abdominal… (2018) · Cochrane | RR 2.48 [1.13, 5.45] | 10 studies · 678 participants | Moderate |
Epidural analgesia vs intravenous patient‐controlled analgesia Adverse events (assessed at any time during · adults undergoing intra‐abdominal surgery (including hysterectomies, radical prostatectomies, Caesarean sections,… Epidural analgesia versus patient‐controlled intravenous analgesia for pain following intra‐abdominal… (2018) · Cochrane | RR 0.32 [0.03, 2.95] | 2 studies · 101 participants | Low |
Active cerebral oxygenation monitoring vs blinded cerebral oxygenation monitoring Postoperative neurological injury ( · children and adults undergoing surgery Cerebral near‐infrared spectroscopy (NIRS) for perioperative monitoring of brain oxygenation in children and… (2018) · Cochrane | no estimate extracted | 2 studies · 312 participants | Low |
Active cerebral oxygenation monitoring vs blinded cerebral oxygenation monitoring Postoperative stroke ( · children and adults undergoing surgery Cerebral near‐infrared spectroscopy (NIRS) for perioperative monitoring of brain oxygenation in children and… (2018) · Cochrane | RR 0.25 [0.03, 2.2] | 2 studies · 240 participants | Low |
Active cerebral oxygenation monitoring vs blinded cerebral oxygenation monitoring POD: postoperative delirium ( · children and adults undergoing surgery Cerebral near‐infrared spectroscopy (NIRS) for perioperative monitoring of brain oxygenation in children and… (2018) · Cochrane | RR 0.63 [0.27, 1.45] | 1 study · 190 participants | Low |
Active cerebral oxygenation monitoring vs blinded cerebral oxygenation monitoring POCD defined by original studies ‐ mild ( · children and adults undergoing surgery Cerebral near‐infrared spectroscopy (NIRS) for perioperative monitoring of brain oxygenation in children and… (2018) · Cochrane | RR 0.53 [0.3, 0.95] | 2 studies · 126 participants | Low |
Active cerebral oxygenation monitoring vs blinded cerebral oxygenation monitoring POCD: decline in cognitive function ( · children and adults undergoing surgery Cerebral near‐infrared spectroscopy (NIRS) for perioperative monitoring of brain oxygenation in children and… (2018) · Cochrane | RR 0.62 [0.37, 1.04] | 6 studies · 962 participants | Moderate |
Active cerebral oxygenation monitoring vs blinded cerebral oxygenation monitoring Intraoperative mortality or postoperative mortality: Death ( · children and adults undergoing surgery Cerebral near‐infrared spectroscopy (NIRS) for perioperative monitoring of brain oxygenation in children and… (2018) · Cochrane | RR 0.63 [0.08, 5.03] | 3 studies · 390 participants | Low |
Active cerebral oxygenation monitoring vs blinded cerebral oxygenation monitoring Adverse events · children and adults undergoing surgery Cerebral near‐infrared spectroscopy (NIRS) for perioperative monitoring of brain oxygenation in children and… (2018) · Cochrane | no estimate extracted | NR | No studies |
Pulmonary artery perfusion with blood vs no perfusion during cardiopulmonary bypass All‐cause mortality within longest · adult surgical patients with the need for cardiopulmonary bypass‐dependent heart surgery Pulmonary artery perfusion versus no perfusion during cardiopulmonary bypass for open heart surgery in adults (2018) · Cochrane | Peto OR 1.78 [0.43, 7.4] | 4 studies · 210 participants | Very low |
Pulmonary artery perfusion with blood vs no perfusion during cardiopulmonary bypass Number of participants with pulmonary events within longest · adult surgical patients with the need for cardiopulmonary bypass‐dependent heart surgery Pulmonary artery perfusion versus no perfusion during cardiopulmonary bypass for open heart surgery in adults (2018) · Cochrane | no estimate extracted | NR | No studies |
Pulmonary artery perfusion with blood vs no perfusion during cardiopulmonary bypass Participants with ≥ 1SAE within longest · adult surgical patients with the need for cardiopulmonary bypass‐dependent heart surgery Pulmonary artery perfusion versus no perfusion during cardiopulmonary bypass for open heart surgery in adults (2018) · Cochrane | RR 1.12 [0.66, 1.89] | 3 studies · 180 participants | Very low |
Pulmonary artery perfusion with blood vs no perfusion during cardiopulmonary bypass Last measured PaO2/FiO2 ratio (mmHg) in all trials, irrespective of overall risk of bias · adult surgical patients with the need for cardiopulmonary bypass‐dependent heart surgery Pulmonary artery perfusion versus no perfusion during cardiopulmonary bypass for open heart surgery in adults (2018) · Cochrane | no estimate extracted | 3 studies · 119 participants | Very low |
Low tidal volume vs high tidal volume Mortality · adults (aged > 16 years) without acute lung injury needing mechanical positive pressure ventilation during their… Intraoperative use of low volume ventilation to decrease postoperative mortality, mechanical ventilation,… (2018) · Cochrane | RR 0.8 [0.42, 1.53] | 12 studies · 1207 participants | Low |
Low tidal volume vs high tidal volume Pneumonia · adults (aged > 16 years) without acute lung injury needing mechanical positive pressure ventilation during their… Intraoperative use of low volume ventilation to decrease postoperative mortality, mechanical ventilation,… (2018) · Cochrane | RR 0.45 [0.25, 0.82] | 7 studies · 778 participants | Moderate |
Low tidal volume vs high tidal volume Need for postoperative non‐invasive ventilatory support · adults (aged > 16 years) without acute lung injury needing mechanical positive pressure ventilation during their… Intraoperative use of low volume ventilation to decrease postoperative mortality, mechanical ventilation,… (2018) · Cochrane | RR 0.31 [0.15, 0.64] | 3 studies · 506 participants | Moderate |
Low tidal volume vs high tidal volume Need for postoperative invasive ventilatory support · adults (aged > 16 years) without acute lung injury needing mechanical positive pressure ventilation during their… Intraoperative use of low volume ventilation to decrease postoperative mortality, mechanical ventilation,… (2018) · Cochrane | RR 0.33 [0.14, 0.77] | 11 studies · 957 participants | Moderate |
Low tidal volume vs high tidal volume Intensive care unit length of stay (days) · adults (aged > 16 years) without acute lung injury needing mechanical positive pressure ventilation during their… Intraoperative use of low volume ventilation to decrease postoperative mortality, mechanical ventilation,… (2018) · Cochrane | no estimate extracted | 5 studies · 898 participants | Low |
Low tidal volume vs high tidal volume Hospital length of stay (days) · adults (aged > 16 years) without acute lung injury needing mechanical positive pressure ventilation during their… Intraoperative use of low volume ventilation to decrease postoperative mortality, mechanical ventilation,… (2018) · Cochrane | no estimate extracted | 14 studies · 1298 participants | Low |
Low tidal volume vs high tidal volume Barotrauma: pneumothorax · adults (aged > 16 years) without acute lung injury needing mechanical positive pressure ventilation during their… Intraoperative use of low volume ventilation to decrease postoperative mortality, mechanical ventilation,… (2018) · Cochrane | RR 1.77 [0.52, 5.99] | 5 studies · 708 participants | Very low |
Intervention NR Postoperative delirium (POD) within 7 days (As assessed by any method such as the Mini‐Mental State Examination (MMSE) and Confusion Assessment Method (CAM) in the first week after operation) · adults aged 18 years or over undergoing general anaesthesia for non‐cardiac or non‐neurosurgical elective operations Processed electroencephalogram and evoked potential techniques for amelioration of postoperative delirium… (2018) · Cochrane | RR 0.71 [0.59, 0.85] | 3 studies · 2197 participants | Moderate |
Intervention NR Postoperative cognitive dysfunction (POCD) (As determined by any method of assessing POCD including a battery of neuropsychological tests according to the criteria described by the International Study of Postoperative Cognitive Dysfunction (ISPOCD)) · adults aged 18 years or over undergoing general anaesthesia for non‐cardiac or non‐neurosurgical elective operations Processed electroencephalogram and evoked potential techniques for amelioration of postoperative delirium… (2018) · Cochrane | RR 0.84 [0.69, 1.02] | 3 studies · 1989 participants | Moderate |
Intervention NR All‐cause mortality · adults aged 18 years or over undergoing general anaesthesia for non‐cardiac or non‐neurosurgical elective operations Processed electroencephalogram and evoked potential techniques for amelioration of postoperative delirium… (2018) · Cochrane | RR 1.01 [0.62, 1.64] | 1 study · 1155 participants | Low |
Intervention NR Any postoperative complication · adults aged 18 years or over undergoing general anaesthesia for non‐cardiac or non‐neurosurgical elective operations Processed electroencephalogram and evoked potential techniques for amelioration of postoperative delirium… (2018) · Cochrane | RR 0.51 [0.37, 0.71] | 1 study · 902 participants | Moderate |
Intervention NR Postoperative length of stay (days) · adults aged 18 years or over undergoing general anaesthesia for non‐cardiac or non‐neurosurgical elective operations Processed electroencephalogram and evoked potential techniques for amelioration of postoperative delirium… (2018) · Cochrane | no estimate extracted | 1 study · 1155 participants | Low |