What do systematic reviews say?

Multiple vs double‐injection technique

Multiple showed no clear difference in intravascular injection compared with double‐injection technique (moderate certainty).

• Single, double or multiple‐injection techniques for non‐ultrasound guided axillary brachial plexus block in adults… 2016 · Cochrane Headline outcomes only
  RR 0.69 [0.32, 1.49]
  7 studies · 676 participants
  Moderate

Multiple vs double‐injection technique

• Single, double or multiple‐injection techniques for non‐ultrasound guided axillary brachial plexus block in adults… 2016 · Cochrane Headline outcomes only
  no estimate extracted
  6 studies · 510 participants
  Low

Single layer gastrointestinal anastomosis vs Double layer gastrointestinal anastomosis

It is very uncertain whether single layer gastrointestinal anastomosis changes anastomotic leak Odds ratio compared with double layer gastrointestinal anastomosis (very low certainty).

• Single layer versus double layer suture anastomosis of the gastrointestinal tract 2012 · Cochrane Headline outcomes only
  OR 0.76 [0.44, 1.32]
  7 studies · 842 participants
  Very low

Single layer gastrointestinal anastomosis vs Double layer gastrointestinal anastomosis

• Single layer versus double layer suture anastomosis of the gastrointestinal tract 2012 · Cochrane Headline outcomes only
  no estimate extracted
  2 studies · 218 participants
  Low

Single layer gastrointestinal anastomosis vs Double layer gastrointestinal anastomosis

• Single layer versus double layer suture anastomosis of the gastrointestinal tract 2012 · Cochrane Headline outcomes only
  no estimate extracted
  3 studies · 390 participants
  Low

Single layer gastrointestinal anastomosis vs Double layer gastrointestinal anastomosis

Single layer gastrointestinal anastomosis showed no clear difference in mortality Odds ratio compared with double layer gastrointestinal anastomosis (low certainty).

• Single layer versus double layer suture anastomosis of the gastrointestinal tract 2012 · Cochrane Headline outcomes only
  OR 0.56 [0.19, 1.63]
  4 studies · 403 participants
  Low

Single layer gastrointestinal anastomosis vs Double layer gastrointestinal anastomosis

Single layer gastrointestinal anastomosis showed no clear difference in major complications Odds ratio compared with double layer gastrointestinal anastomosis (low certainty).

• Single layer versus double layer suture anastomosis of the gastrointestinal tract 2012 · Cochrane Headline outcomes only
  OR 0.71 [0.44, 1.16]
  7 studies · 842 participants
  Low

Single layer gastrointestinal anastomosis vs Double layer gastrointestinal anastomosis

Single layer gastrointestinal anastomosis showed no clear difference in anastomotic leak in high quality trials Odds ratio compared with double layer gastrointestinal anastomosis (moderate certainty).

• Single layer versus double layer suture anastomosis of the gastrointestinal tract 2012 · Cochrane Headline outcomes only
  OR 1.13 [0.42, 3.01]
  3 studies · 353 participants
  Moderate

Single layer gastrointestinal anastomosis vs Double layer gastrointestinal anastomosis

It is very uncertain whether single layer gastrointestinal anastomosis changes anastomotic leak in poor quality trials Odds ratio compared with double layer gastrointestinal anastomosis (very low certainty).

• Single layer versus double layer suture anastomosis of the gastrointestinal tract 2012 · Cochrane Headline outcomes only
  OR 0.63 [0.32, 1.24]
  4 studies · 489 participants
  Very low

Surface‐modified vs standard catheter

• Non‐pharmacological interventions for preventing clotting of extracorporeal circuits during continuous renal… 2021 · Cochrane Headline outcomes only
  no estimate extracted
  1 study · 262 participants
  Low

Surface‐modified vs standard catheter

It is very uncertain whether surface‐modified changes death from any cause at day 28 of compared with standard double‐lumen catheter with identical geometry and flow design (very low certainty).

• Non‐pharmacological interventions for preventing clotting of extracorporeal circuits during continuous renal… 2021 · Cochrane Headline outcomes only
  RR 1.08 [0.76, 1.53]
  1 study · 236 participants
  Very low

Surface‐modified vs standard catheter

Surface‐modified showed no clear difference in recovery of kidney function compared with standard double‐lumen catheter with identical geometry and flow design (low certainty).

• Non‐pharmacological interventions for preventing clotting of extracorporeal circuits during continuous renal… 2021 · Cochrane Headline outcomes only
  RR 0.91 [0.7, 1.2]
  1 study · 236 participants
  Low

Surface‐modified vs standard catheter

Surface‐modified showed no clear difference in vascular access complications compared with standard double‐lumen catheter with identical geometry and flow design (low certainty).

• Non‐pharmacological interventions for preventing clotting of extracorporeal circuits during continuous renal… 2021 · Cochrane Headline outcomes only
  RR 0.33 [0.09, 1.2]
  1 study · 236 participants
  Low

Multiple vs single‐injection technique

Multiple showed no clear difference in secondary analgesia failure ‐ tourniquet pain compared with single‐injection technique (high certainty).

• Single, double or multiple‐injection techniques for non‐ultrasound guided axillary brachial plexus block in adults… 2016 · Cochrane Headline outcomes only
  RR 0.97 [0.3, 3.11]
  4 studies · 379 participants
  High

Multiple vs single‐injection technique

Multiple showed no clear difference in complete failure of block1 compared with single‐injection technique (moderate certainty).

• Single, double or multiple‐injection techniques for non‐ultrasound guided axillary brachial plexus block in adults… 2016 · Cochrane Headline outcomes only
  RR 0.31 [0.03, 2.71]
  7 studies · 484 participants
  Moderate

Multiple vs single‐injection technique

• Single, double or multiple‐injection techniques for non‐ultrasound guided axillary brachial plexus block in adults… 2016 · Cochrane Headline outcomes only
  no estimate extracted
  2 studies · 206 participants
  Low

Multiple vs single‐injection technique

Multiple showed no clear difference in intravascular injection compared with single‐injection technique (moderate certainty).

• Single, double or multiple‐injection techniques for non‐ultrasound guided axillary brachial plexus block in adults… 2016 · Cochrane Headline outcomes only
  RR 1.35 [0.2, 9.06]
  4 studies · 352 participants
  Moderate

Multiple vs single‐injection technique

• Single, double or multiple‐injection techniques for non‐ultrasound guided axillary brachial plexus block in adults… 2016 · Cochrane Headline outcomes only
  no estimate extracted
  3 studies · 244 participants
  Low

Multiple vs single‐injection technique

Multiple leads to lower primary anaesthesia failure compared with single‐injection technique (high certainty).

• Single, double or multiple‐injection techniques for non‐ultrasound guided axillary brachial plexus block in adults… 2016 · Cochrane Headline outcomes only
  RR 0.25 [0.14, 0.42]
  9 studies · 712 participants
  High

Multiple vs single‐injection technique

Multiple showed no clear difference in secondary analgesia failure ‐ intraoperative sedation required compared with single‐injection technique (high certainty).

• Single, double or multiple‐injection techniques for non‐ultrasound guided axillary brachial plexus block in adults… 2016 · Cochrane Headline outcomes only
  RR 0.7 [0.41, 1.19]
  5 studies · 482 participants
  High