Does Point of Care Ultrasound Improve Resuscitation Markers in Undifferentiated Hypotension? An International Randomized Controlled Trial From The Sonography in Hypotension and Cardiac Arrest in the Emergency Department (SHoC-ED) Series.

Introduction Point of Care Ultrasound (PoCUS) protocols are commonly used to guide resuscitation for patients with undifferentiated hypotension, yet there is a paucity of evidence for any outcome benefit. We undertook an international multicenter randomized controlled trial (RCT) to assess the impact of a PoCUS protocol on key clinical outcomes. Here we report on resuscitation markers.  Methods Adult patients presenting to six emergency departments (ED) in Canada and South Africa with undifferentiated hypotension (systolic blood pressure (SBP) <100mmHg or a Shock Index >1.0) were randomized to receive a PoCUS protocol or standard care (control). Reported physiological markers include shock index (SI), and modified early warning score (MEWS), with biochemical markers including venous bicarbonate and lactate, at baseline and four hours.  Results A total of 273 patients were enrolled, with data collected for 270. Baseline characteristics were similar for each group. Improvements in mean values for each marker during initial treatment were similar between groups: Shock Index; mean reduction in Control 0.39, 95% CI 0.34 to 0.44 vs. PoCUS 0.33, 0.29 to 0.38; MEWS, mean reduction in Control 2.56, 2.22 to 2.89 vs. PoCUS 2.91, 2.49 to 3.32; Bicarbonate, mean reduction in Control 2.71 mmol/L, 2.12 to 3.30 mmol/L vs. PoCUS 2.30 mmol/L, 1.75 to 2.84 mmol/L, and venous lactate, mean reduction in Control 1.39 mmol/L, 0.93 to 1.85 mmol/L vs. PoCUS 1.31 mmol/L, 0.88 to 1.74 mmol/L. Conclusion We found no meaningful difference in physiological and biochemical resuscitation markers with or without the use of a PoCUS protocol in the resuscitation of undifferentiated hypotensive ED patients. We are unable to exclude improvements in individual patients or in specific shock types.