Barandun 1985.

Methods	Double‐blind parallel‐group randomised controlled trial
Participants	Baseline characteristics Number randomised: 66 participants Number analysed: 55 participants Pirenzepine Age (years; mean (SD)): ‐ Number of participants (n): 27 Gender (male/female; n): ‐ Cimetidine Age (years; mean (SD)): ‐ Number of participants (n): 28 Gender (male/female; n): ‐ Inclusion criteria Age > 16 years Patients in surgical ICU Exclusion criteria Gastroscopy not possible On therapy for ulcus Receiving operation of stomach Baseline imbalances: baseline imbalances comparable, also in terms of severity of injury/trauma
Interventions	Pirenzepine Dose (total/d): 40 mg Duration of treatment (days): ‐ Route: IV Intervention: 4 × 10 mg IV Concomitant medications: ‐ Cimetidine Dose (total/d): 800 mg Duration of treatment (days): ‐ Route: IV Intervention: 4 × 200 mg IV Concomitant medications: ‐ Adherence to regimen: 11 participants withdrew from the trial. However, no reasons are mentioned in the trial report. Also no mention of which interventional group these 11 participants belonged to Duration of trial: ‐ Duration of follow‐up: not clearly mentioned, probably until discharge
Outcomes	Outcomes sought in review and reported in trial Clinically important upper GI bleeding Adverse events of interventions Outcomes sought but not reported in trial VAP All‐cause mortality in ICU All‐cause mortality in hospital Duration of ICU stay Duration of intubation Number of participants requiring blood transfusion Number of units of blood transfused Outcomes reported in trial but not used in review Number of lesions on gastroscopy
Notes	Setting: Surgical ICU, Chur, Switzerland Source of funding: ‐ Conflicts of interest: ‐ Ethics approval: ‐ Informed consent: ‐ Clinical trials registration: ‐ Sample size calculation: ‐
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Comment: not enough information reported on method of sequence generation
Allocation concealment (selection bias)	Unclear risk	Comment: not enough information reported on method of allocation concealment
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Comment: This appears to be a double‐dummy placebo‐controlled trial, in which participants from group 1 got a placebo that looks like the intervention in group 2 and vice versa. Thus personnel would have been blinded and likelihood of performance bias is low
Blinding (detection bias) Clinically important upper GI bleeding	Unclear risk	Comment: not enough information reported on the criteria for diagnosis of upper GI bleeding
Blinding (detection bias) Nosocomial pneumonia	Unclear risk	Comment: The trial did not address this outcome
Blinding of outcome assessment (detection bias) Adverse reactions of interventions	Low risk	Comment: This appears to be a double‐dummy placebo‐controlled trial, in which participants from group 1 got a placebo that looks like the intervention in group 2 and vice versa. Thus the likelihood of detection bias seems low
Incomplete outcome data (attrition bias) All outcomes	High risk	Comment: 11 participants withdrew from the trial, but reasons for withdrawal and the group to which they were randomised are not clearly mentioned in the trial report
Selective reporting (reporting bias)	Unclear risk	Comment: All intended outcomes were reported but no clear mention of the number of participants in the cimetidine group who had confusion and high K levels
Other bias	Low risk	Comment: The trial report is unclear on the source of funding. No other sources of bias detected