Ultrasonography in the intensive care unit (ICU) has become a valuable tool for expeditiously, safely and effectively diagnosing and treating a myriad of conditions commonly encountered in this setting. Most surgeons are familiar with FAST (Focused Assessment with Sonography in Trauma) and can readily grasp the fundamentals of a limited or directed ultrasonographic exam. Thus, with appropriate training and practice, surgeons can utilize this tool in visualizing, characterizing and treating life-threatening conditions in their role as intensivists in the surgical ICU (SICU). In this review we will discuss the role of ultrasonography in evaluating the acute cardiac status of a patient in the SICU as well as its use in general critical care for assessing the thoracic, abdominal and vascular systems.