COMBED: Rapid non‐invasive Cardiac Output Monitoring Baseline assessment in adult Emergency Department patients with haemodynamic instability

Objective The application of rapid, non‐operator‐dependent, non‐invasive cardiac output monitoring (COM) may provide early physiological information in ED patients with haemodynamic instability (HI). Our primary objective was to assess the feasibility of measuring pre‐intervention (baseline) cardiac index (CI) and associated haemodynamic parameters. Methods We performed a prospective observational study of adults shortly after presentation to the ED of a large university hospital with tachycardia or hypotension or both. We applied non‐invasive COM for 5 min and recorded CI, mean arterial pressure (MAP), stroke volume index (SVI) and systemic vascular resistance index (SVRI). We assessed for differences between those presenting with hypotension or hypotension and tachycardia with tachycardia alone and between those with or without suspected infection. Results We obtained haemodynamic parameters in 46 of 49 patients. In patients with hypotension or hypotension and tachycardia (n = 15) rather than tachycardia alone (n = 31), we observed a lower MAP (60.8 vs 87.7, P 90% of ED patients presenting with haemodynamic instability. Compared with tachycardia alone, patients with hypotension had lower cardiac index, mean arterial pressure and heart rate, while those with suspected infection had a lower systemic vascular resistance index. This technology provides novel insights into the early state of the circulation in ED patients with haemodynamic instability.