To date, ultrasound-guided centeses have required the use of large, diagnostic ultrasound equipment that can be cumbersome and not readily available. In this study, we sought to evaluate the use of portable, hand-carried ultrasound devices in guidance of pericardiocentesis and thoracentesis. Hand-carried ultrasound was used to define location of the maximal extent of the effusion and its proximity to the skin surface, confirm needle entry and site, and to evaluate postprocedural result. A total of 12 patients who were stable and hospitalized were prospectively enrolled, 9 for pericardiocentesis and 3 for thoracentesis. We concluded that under the direction of a suitably trained physician, hand-carried ultrasound provided images suitable for guidance of a pericardiocentesis or thoracentesis preprocedurally, intraprocedurally, and postprocedurally.