Diagnostic Point-of-Care Ultrasound for the Cardiac Surgical Patient, From Head-to-Toe.

Diagnostic point-of-care ultrasound (POCUS) has rapidly evolved into an indispensable bedside tool across critical care and perioperative medicine. Patients undergoing cardiothoracic (CT) surgery present with complex, multi-organ vulnerabilities ranging from neurologic injury and respiratory failure to hemodynamic instability, renal dysfunction, and thromboembolic disease. This review outlines how diagnostic POCUS, as described in the recent JoVE Methods Collection, can be applied in a structured "head-to-toe" framework to facilitate the care of CT surgery patients. At the cranial level, modalities such as optic nerve sheath diameter and transcranial Doppler offer non-invasive insights into intracranial pressure and cerebrovascular flow. Airway and lung ultrasound support rapid diagnosis of intubation complications, pneumothorax, effusion, and parenchymal edema, while cardiac ultrasound provides a stepwise approach to evaluating hypotension, ventricular dysfunction, and pericardial effusion. Diaphragmatic assessment further informs the management of phrenic nerve injury and postoperative respiratory compromise. Abdominal ultrasound, including renal evaluation and venous excess ultrasound (VExUS), aids in identifying obstructive causes of acute kidney injury and in assessing the systemic impact of right-sided congestion. Finally, lower-extremity vascular and musculoskeletal POCUS permits efficient screening for deep vein thrombosis and provides a window into frailty in the chronically ill. By synthesizing these diagnostic workflows, this review highlights how structured, multimodal POCUS can accelerate diagnosis, individualize therapy, and reduce reliance on resource-intensive testing in a vulnerable surgical population. Broader adoption and training may help standardize POCUS integration into cardiothoracic perioperative care and ultimately improve patient outcomes.