Hand-held echocardiography with Doppler capability for the assessment of critically-ill patients:: is it reliable?

Objective. To evaluate the diagnostic capability of a hand-carried ultrasound device (HCU) in critically ill patients when using conventional transthoracic echocardiography (TTE) as a reference. Design. Prospective, descriptive study. Setting. Medical-surgical intensive care unit of a teaching hospital. Patients. All patients requiring a TTE study were eligible. Interventions. Each patient underwent an echocardiographic examination using a full-feature echocardiographic platform (Sonos 5500, Philips Medical Systems, Andover, MA) and a small battery-operated device (SonoHeart Elite, SonoSite, Bothell, WA). The operators (level III training in echocardiography) were randomized (HCU vs. TTE) and they independently interpreted the echocardiograms at the patient bedside. Results. During a 2-month period, 55 consecutive patients (age: 61+/-16 years, simplified acute physiology score 46+/-15, body mass index 26+/-7) were studied, 40 of them being mechanically ventilated (73%). The number of acoustic windows was comparable using HCU and TTE (2.3+/-0.8 vs. 2.4+/-0.8: P=0.24). The overall diagnostic accuracy of HCU was lower compared with conventional TTE (137/171 vs. 158/171 clinical questions solved: P=0.002), reaching 80% and 92%, respectively. Despite its spectral Doppler capability, HCU missed diagnoses that were adequately identified by TTE: elevated left ventricular pressure (n=2), relevant valvulopathy (n=2) and moderate (n=4) or severe (n=2) pulmonary hypertension. Acute management was altered by HCU and TTE findings in 27 patients (49%) and 28 patients (51%), respectively. Conclusions. In this study, HCU had a lower diagnostic accuracy compared with conventional TTE, despite its spectral Doppler capability. Further studies are needed to validate these evolving diagnostic tools in critical care settings.