Sethi, Jaskaran

Introduction: Extracorporeal membrane oxygenation (ECMO) has been extensively used for potentially reversible acute respiratory failure associated with severe influenza A (H1N1) pneumonia; however, it remains an expensive, resource-intensive therapy, with a high associated mortality. This systematic review and meta-analysis aims to summarize and pool outcomes data available in the published literature to guide clinical decision-making and further research. Methods: We conducted a systematic search of MEDLINE (1966 to April 15, 2015), EMBASE (1980 to April 15, 2015), CENTRAL, and Google Scholar for patients with severe H1N1 pneumonia and respiratory failure who received ECMO. The study validity was appraised by Newcastle–Ottawa Scale. The primary outcome was all-cause mortality. The secondary outcomes were duration of ECMO therapy, mechanical ventilation, and Intensive Care Unit (ICU) length of stay. Results: Of 698 abstracts screened and 142 full-text articles reviewed, we included 13 studies with a total of 494 patients receiving ECMO in our final review and meta-analysis. The study validity was satisfactory. The overall mortality was 37.1% (95% confidence interval: 30–45%) limited by underlying heterogeneity ( I 2 = 65%, P value of Q statistic = 0.006). The median duration for ECMO was 10 days, mechanical ventilation was 19 days, and ICU length of stay was 33 days. Exploratory meta-regression did not identify any statistically significant moderator of mortality ( P < 0.05), except for the duration of pre-ECMO mechanical ventilation in days (coefficient 0.19, standard error: 0.09, Z = 2.01, P < 0.04, R 2 = 0.16). The visual inspection of funnel plots did not suggest the presence of publication bias. Conclusions: ECMO therapy may be used as an adjunct or salvage therapy for severe H1N1 pneumonia with respiratory failure. It is associated with a prolonged duration of ventilator support, ICU length of stay, and high mortality. Initiating ECMO early once the patient has been instituted on mechanical ventilation may result in improved survival.

Aim: Platelet function is intricately linked to the pathophysiology of critical Illness, and some studies have shown that antiplatelet therapy (APT) may decrease mortality and incidence of acute respiratory distress syndrome (ARDS) in these patients. Our objective was to understand the efficacy of APT by conducting a meta-analysis. Materials and Methods: We conducted a meta-analysis using PubMed, Central, Embase, The Cochrane Central Register, the ClinicalTrials.gov Website, and Google Scholar. Studies were included if they investigated critically ill patients receiving antiplatelet therapy and mentioned the outcomes being studied (mortality, duration of hospitalization, ARDS, and need for mechanical ventilation). Results: We found that there was a significant reduction in all-cause mortality in patients on APT compared to control (odds ratio [OR]: 0.83; 95% confidence interval [CI]: 0.70–0.97). Both the incidence of acute lung injury/ARDS (OR: 0.67; 95% CI: 0.57–0.78) and need for mechanical ventilation (OR: 0.74; 95% CI: 0.60–0.91) were lower in the antiplatelet group. No significant difference in duration of hospitalization was observed between the two groups (standardized mean difference: −0.02; 95% CI: −0.11–0.07). Conclusion: Our meta-analysis suggests that critically ill patients who are on APT have an improved survival, decreased incidence of ARDS, and decreased need for mechanical ventilation.