Is point-of-care ultrasound a reliable predictor of outcome during atraumatic, non-shockable cardiac arrest? A systematic review and meta-analysis from the SHoC investigators

Aims: To evaluate the accuracy of PoCUS in predicting return of spontaneous circulation (ROSC), survival to hospital admission (SHA), and survival to hospital discharge (SHD)in adult non-traumatic, non-shockable out-of-hospital or emergency department cardiac arrest. Methods: Medline, EMBASE, Cochrane, CINAHL, ClinicalTrials.gov and the World Health Organization Registry were searched for eligible studies. Data analysis was completed according to PRISMA guidelines. A random-effects meta-analysis model was used with I-squared statistics for heterogeneity. Results: Ten studies (1486 participants)were included. Cardiac activity on PoCUS had a pooled sensitivity of 60.3% (95% confidence interval 38.1%–78.9%)and specificity of 91.5%(80.8%–96.5%)for ROSC. The sensitivity of cardiac activity on PoCUS for predicting ROSC was 26.1%(7.8%–59.6%)in asystole compared with 76.7% (61.3%–87.2%)in PEA. Cardiac activity on PoCUS, compared to absence, had odd ratios of 16.90 (6.18–46.21)for ROSC, 10.30(5.32–19.98)for SHA and 8.03(3.01–21.39)for SHD. Positive likelihood ratio (LR)was 6.87(3.21–14.71)and negative LR was 0.27(0.12−0.60)for ROSC. Conclusions: Cardiac activity on PoCUS was associated with improved odds for ROSC, SHA, and SHD in non-traumatic, non-shockable cardiac arrest. We report a lower sensitivity and higher negative likelihood ratio, but greater heterogeneity compared to previous systematic reviews. PoCUS may provide valuable information in the management of non-traumatic PEA or asystole, but should not be viewed as the sole predictor in determining outcomes.