Comparing Effectiveness of Initial Airway Interventions for Out-of-Hospital Cardiac Arrest: A Systematic Review and Network Meta-analysis of Clinical Controlled Trials.

STUDY OBJECTIVE: We compare effectiveness of different airway interventions during cardiopulmonary resuscitation for patients with out-of-hospital cardiac arrest. METHODS: We systematically searched the PubMed and EMBASE databases from their inception through August 2018 and selected randomized controlled trials or quasi randomized controlled trials comparing intubation, supraglottic airways, or bag-valve-mask ventilation for treating adult out-of-hospital cardiac arrest patients. We performed a network meta-analysis along with sensitivity analyses to investigate the influence of high intubation success rate on meta-analytic results. RESULTS: A total of 8 randomized controlled trials and 3 quasi randomized controlled trials were included in the network meta-analysis: 7,361 patients received intubation, 7,475 received supraglottic airway, and 1,201 received bag-valve-mask ventilation. The network meta-analysis indicated no differences among these interventions for survival or neurologic outcomes at hospital discharge. Rather, network meta-analysis suggested that supraglottic airway improved the rate of return of spontaneous circulation compared with intubation (odds ratio 1.11; 95% confidence interval 1.03 to 1.20) or bag-valve-mask ventilation (odds ratio 1.35; 95% confidence interval 1.11 to 1.63). Furthermore, intubation improved the rate of return of spontaneous circulation compared with bag-valve-mask ventilation (odds ratio 1.21; 95% confidence interval 1.01 to 1.44). The sensitivity analyses revealed that the meta-analytic results were sensitive to the intubation success rates across different out-of-hospital care systems. CONCLUSION: Although there were no differences in long-term survival or neurologic outcome among these airway interventions, these system-based comparisons demonstrated that supraglottic airway was better than intubation or bag-valve-mask ventilation and intubation was better than bag-valve-mask ventilation in improving return of spontaneous circulation. The intubation success rate greatly influenced the meta-analytic results, and therefore these comparison results should be interpreted with these system differences in mind.