What do systematic reviews say?

Bilateral subtotal thyroidectomy vs the Dunhill procedure

• Thyroid surgery for Graves’ disease and Graves’ ophthalmopathy 2015 · Cochrane Headline outcomes only
  no estimate extracted
  3 studies · 642 participants
  GRADE not reported

Glutamine‐supplemented nutrition vs non‐supplemented nutrition

Glutamine‐supplemented nutrition showed no clear difference in long‐term mortality (closest to six month) compared with non‐supplemented nutrition (moderate certainty).

• Glutamine supplementation for critically ill adults 2014 · Cochrane Headline outcomes only
  RR 1 [0.89, 1.12]
  11 studies · 2277 participants
  Moderate

Summary of findings TIVA vs inhalational maintenance of anaesthesia

It is very uncertain whether summary of findings TIVA changes mortality At 30 days compared with inhalational maintenance of anaesthesia (very low certainty).

• Intravenous versus inhalational maintenance of anaesthesia for postoperative cognitive outcomes in elderly people… 2018 · Cochrane Headline outcomes only
  OR 1.21 [0.33, 4.45]
  3 studies · 271 participants
  Very low

Intervention not reported

The intervention showed no clear difference in procedural mortality (high certainty).

• Bypass surgery for chronic lower limb ischaemia 2017 · Cochrane Headline outcomes only
  OR 1.67 [0.66, 4.19]
  5 studies · 913 participants
  High

Intervention not reported

It is very uncertain whether the intervention changes reported mortality, low risk of bias studies only (very low certainty).

• Interventions for protecting renal function in the perioperative period 2013 · Cochrane Headline outcomes only
  OR 1.01 [0.52, 1.97]
  19 studies · 1604 participants
  Very low

Buffered vs non‐buffered crystalloid intravenous fluid

Buffered showed no clear difference in mortality (in‐hospital death and 30‐day mortality) compared with non‐buffered crystalloid intravenous fluid (low certainty).

• Perioperative administration of buffered versus non‐buffered crystalloid intravenous fluid to improve outcomes… 2017 · Cochrane Headline outcomes only
  OR 1.85 [0.37, 9.33]
  3 studies · 267 participants
  Low

Hand‐assisted laparoscopic repair vs EVAR

• Laparoscopic surgery for elective abdominal aortic aneurysm repair 2017 · Cochrane Headline outcomes only
  no estimate extracted
  1 study · 100 participants
  Low

Remote ischaemic preconditioning (RIPC) vs no RIPC

Remote ischaemic preconditioning (RIPC) showed no clear difference in perioperative mortality (within 1 month after operation) compared with no RIPC (moderate certainty).

• Remote ischaemic preconditioning versus no remote ischaemic preconditioning for vascular and endovascular surgical… 2023 · Cochrane Headline outcomes only
  RR 1.41 [0.59, 3.4]
  10 studies · 965 participants
  Moderate

Active cerebral oxygenation monitoring vs blinded cerebral oxygenation monitoring

Active cerebral oxygenation monitoring showed no clear difference in intraoperative mortality or postoperative mortality: Death ( compared with blinded cerebral oxygenation monitoring (low certainty).

• Cerebral near‐infrared spectroscopy (NIRS) for perioperative monitoring of brain oxygenation in children and adults 2018 · Cochrane Headline outcomes only
  RR 0.63 [0.08, 5.03]
  3 studies · 390 participants
  Low

Laparoscopic vs open surgery

It is very uncertain whether laparoscopic changes late overall mortality (after the first 30 postoperative days) compared with open surgery (very low certainty).

• Laparoscopic versus open resection for sigmoid diverticulitis 2017 · Cochrane Headline outcomes only
  RR 2.04 [0.19, 21.77]
  1 study · 93 participants
  Very low

Intervention not reported

It is very uncertain whether the intervention changes postoperative mortality (very low certainty).

• Fibrin sealants for the prevention of postoperative pancreatic fistula following pancreatic surgery 2023 · Cochrane Headline outcomes only
  Peto OR 1.41 [0.63, 3.13]
  2 studies · 351 participants
  Very low

Intervention not reported

It is very uncertain whether the intervention changes postoperative mortality (very low certainty).

• Fibrin sealants for the prevention of postoperative pancreatic fistula following pancreatic surgery 2023 · Cochrane Headline outcomes only
  Peto OR 0.39 [0.12, 1.29]
  7 studies · 1051 participants
  Very low

Intervention not reported

It is very uncertain whether the intervention changes postoperative mortality (very low certainty).

• Fibrin sealants for the prevention of postoperative pancreatic fistula following pancreatic surgery 2023 · Cochrane Headline outcomes only
  Peto OR 0.24 [0.05, 1.06]
  5 studies · 517 participants
  Very low

Glutamine‐supplemented nutrition vs non‐supplemented nutrition

Glutamine‐supplemented nutrition showed no clear difference in short‐term mortality (within hospital stay or closest to one month) compared with non‐supplemented nutrition (low certainty).

• Glutamine supplementation for critically ill adults 2014 · Cochrane Headline outcomes only
  RR 0.89 [0.78, 1.02]
  36 studies · 3454 participants
  Low

Cell salvage vs no cell salvage

• Cell salvage for minimising perioperative allogeneic blood transfusion in adults undergoing elective surgery 2023 · Cochrane Headline outcomes only
  1.19 [0.39, 3.65]
  6 studies · 384 participants
  Very low

Cell salvage vs no cell salvage

• Cell salvage for minimising perioperative allogeneic blood transfusion in adults undergoing elective surgery 2023 · Cochrane Headline outcomes only
  0.13 [0.01, 2.07]
  4 studies · 209 participants
  Very low

Cell salvage vs no cell salvage

It is very uncertain whether cell salvage changes mortality (up to 90 days) compared with no cell salvage (very low certainty).

• Cell salvage for minimising perioperative allogeneic blood transfusion in adults undergoing elective surgery 2023 · Cochrane Headline outcomes only
  RR 0.86 [0.5, 1.48]
  21 studies · 2491 participants
  Very low

Cell salvage vs no cell salvage

• Cell salvage for minimising perioperative allogeneic blood transfusion in adults undergoing elective surgery 2023 · Cochrane Headline outcomes only
  0.46 [0.06, 3.33]
  4 studies · 651 participants
  Very low

Cell salvage vs no cell salvage

It is very uncertain whether cell salvage changes mortality (up to 90 days) compared with no cell salvage (very low certainty).

• Cell salvage for minimising perioperative allogeneic blood transfusion in adults undergoing elective surgery 2023 · Cochrane Headline outcomes only
  RD 0
  1 study · 69 participants
  Very low

Intervention not reported

The intervention probably leads to higher early mortality (90 days) (moderate certainty).

• Lung volume reduction surgery for diffuse emphysema 2016 · Cochrane Headline outcomes only
  OR 6.16 [3.22, 11.79]
  5 studies · 1489 participants
  Moderate