What is the ideal approach for emergent pericardiocentesis using point-of-care ultrasound guidance?

BACKGROUND: Traditionally performed using a subxiphoid approach, the increasing use of pointof- care ultrasound in the emergency department has made other approaches (parasternal and apical) for pericardiocentesis viable. The aim of this study is to identify the ideal approach for emergency-physicianperformed ultrasound-guided pericardiocentesis as determined by ultrasound image quality, distance from surface to pericardial fluid, and likely obstructions or complications. METHODS: A retrospective review of point-of-care cardiac ultrasound examinations was performed in two urban academic emergency departments for the presence of pericardial eff usions. The images were reviewed for technical quality, distance of eff usion from skin surface, and predicted complications. RESULTS: A total of 166 pericardial effusions were identified during the study period. The mean skin-to-pericardial fluid distance was 5.6 cm (95% confidence interval [95% CI] 5.2-6.0 cm) for the subxiphoid views, which was significantly greater than that for the parasternal (2.7 cm [95% CI 2.5-2.8 cm], P<0.001) and apical (2.5 cm [95% CI 2.3-2.7 cm], P<0.001) views. The subxiphoid view had the highest predicted complication rate at 79.7% (95% CI 71.5%-86.4%), which was significantly greater than the apical (31.9%; 95% CI 21.4%-44.0%, P<0.001) and parasternal (20.2%; 95% CI 12.8%-29.5%, P<0.001) views. CONCLUSIONS: Our results suggest that complication rates with pericardiocentesis will be lower via the parasternal or apical approach compared to the subxiphoid approach. The distance from skin to fluid collection is the least in both of these views.