He 2017.

Methods	Parallel‐group randomised controlled trial
Participants	Baseline characteristics Number randomised: 120 participants Number analysed: 120 participants Naloxone Age (years; mean (SD)): 63.1 (6.2) Number of participants (n): 60 Gender (male/female; n): 35/25 Naloxone + pantoprazole Age (years, mean (SD)): 65.1 (6.7) Number of participants (n): 60 Gender (male/female; n): 37/23 Inclusion criteria Age of about 50 years No clinical manifestations of respiratory failure before admission No naloxone allergy history No liver, kidney dysfunction and other diseases Signed informed consent Voluntarily joined the clinical study Exclusion criteria: ‐ Baseline imbalances: no significant difference in primary disease, sex, age, and course of disease between study group and control group
Interventions	Naloxene Dose (total/d): ‐ Duration of treatment (days): ‐ Route: PO Intervention: 0.8 mg of naloxone hydrochloride 2 mL∶ 2 mg (Shandong Xinhua Pharmaceutical Co., Ltd. production) added to 100 mL of 10% glucose water 6 times/d. When the blood gas situation improved, treatment dose was reduced by 50% Concomitant medications: In addition to comparative treatment, 2 groups of patients were given the same regular treatment, including anti‐infective treatment, low‐flow oxygen therapy, phlegm treatment, correct electrolyte imbalance and maintain acid‐base balance, given the treatment of milk and timely nutrition Naloxene + pantoprazole Dose (total/d): ‐ Duration of treatment (days): ‐ Route: PO Intervention: ‐ Concomitant medications: In addition to comparative treatment, 2 groups of patients were given the same regular treatment, including anti‐infective treatment, low‐flow oxygen therapy, phlegm treatment, correct electrolyte imbalance and maintain acid‐base balance, given the treatment of milk and timely nutrition Adherence to regimen: ‐ Duration of trial: May 2009 to May 2014 Duration of follow‐up: ‐
Outcomes	Outcomes sought in review and reported in trial Incidence of clinically important GI bleeding All‐cause mortality in hospital Adverse events of interventions Outcomes sought but not reported in trial Incidence of VAP Duration of ICU stay Duration of intubation Outcomes reported in trial but not used in review Duration of hospital stay Blood gas values
Notes	Setting: ICU Source of funding: ‐ Conflicts of interest: ‐ Ethics approval: ‐ Informed consent: Signed informed consent was required by all participants Clinical trials registration: ‐ Sample size calculation: ‐ Additional notes: ‐
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Comment: insufficient information to allow judgment
Allocation concealment (selection bias)	Unclear risk	Comment: insufficient information to allow judgment
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Comment: insufficient information to allow judgment
Blinding (detection bias) Clinically important upper GI bleeding	High risk	Comment: no details about criteria for diagnosis of upper GI bleeding or blinding of outcome assessors reported
Blinding (detection bias) Nosocomial pneumonia	Unclear risk	Comment: Study did not address this outcome
Blinding of outcome assessment (detection bias) Adverse reactions of interventions	Unclear risk	Comment: insufficient information to allow judgement
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Comment: insufficient information to allow judgement
Selective reporting (reporting bias)	Low risk	Comment: all outcomes reported in Methods section also reported in Results
Other bias	Unclear risk	Comment: insufficient information to allow judgement