Context

Most ultrasound machines are fundamentally the same. Even the most apparently complex machine can be reduced to a simple series of functions. It is vitally important to have an understanding of these function buttons, so that an optimal image is obtained in the challenging circumstances faced by the emergency physician. It is also vital to have knowledge of common artefacts so that they are not confused with pathology, and so that they can also be of assistance.

There is nothing more embarrassing than not being able to find the on/off button. Most machines for near patient scanning are designed to turn on quickly to a set preset, so that image acquisition can commence rapidly. Some have a standby mode.

Larger machines may have an on-board power supply which allows the machine to remain turned on for brief periods away from mains electricity.

This, combined with the standby mode, enables a large machine to be moved from patient to patient.