M-Mode Ultrasound Applications for the Emergency Medicine Physician.

BACKGROUND: M-mode or "motion" mode is a form of ultrasound imaging that is of high clinical utility in the emergency department. It can be used in a variety of situations to evaluate motion and timing, and can document tissue movement in a still image when the recording of a video clip is not feasible.

OBJECTIVES: In this article we describe several straightforward and easily performed applications for the emergency physician to incorporate M-mode into his or her practice, including the evaluation for: 1) pneumothorax, 2) left ventricular systolic function, 3) cardiac tamponade, and 4) hypertrophic cardiomyopathy.

DISCUSSION: The emergency physician and other point-of-care ultrasound providers can use this versatile function in the evaluation of patients for a number of critical cardiopulmonary diagnoses.

CONCLUSION: A great deal of important information may be obtained with M-mode imaging through views and measurements that are relatively easy to obtain.