Résumé : Objective: To describe current use and diagnostic and therapeutic impacts of point-of-care ultrasound (POCUS) in the intensive care unit (ICU). Background: POCUS is of growing importance in the ICU. Several guidelines recommend its use for procedural guidance and diagnostic assessment. Nevertheless, its current use and clinical impact remain unknown. Methods: Prospective multicentric study in 142 ICUs in France, Belgium, and Switzerland. All the POCUS procedures performed during a 24-h period were prospectively analyzed. Data regarding patient condition and the POCUS procedures were collected. Factors associated with diagnostic and therapeutic impacts were identified. Results: Among 1954 patients hospitalized during the study period, 1073 (55 %) POCUS/day were performed in 709 (36 %) patients. POCUS served for diagnostic assessment in 932 (87 %) cases and procedural guidance in 141 (13 %) cases. Transthoracic echocardiography, lung ultrasound, and transcranial Doppler accounted for 51, 17, and 16 % of procedures, respectively. Diagnostic and therapeutic impacts of diagnostic POCUS examinations were 84 and 69 %, respectively. Ultrasound guidance was used in 54 and 15 % of cases for central venous line and arterial catheter placement, respectively. Hemodynamic instability, emergency conditions, transthoracic echocardiography, and ultrasounds performed by certified intensivists themselves were independent factors affecting diagnostic or therapeutic impacts. Conclusions: With regard to guidelines, POCUS utilization for procedural guidance remains insufficient. In contrast, POCUS for diagnostic assessment is of extensive use. Its impact on both diagnosis and treatment of ICU patients seems critical. This study identified factors associated with an improved clinical value of POCUS.