The mechanism of injury is often your first clue that a casualty has received injuries that might lead to an altered mental status. Specifically, exposure to blasts and significant impacts can lead to head injuries that are not always accompanied by obvious external signs. Of course, the presence of injuries that cause massive hemorrhage or altered respiratory status increase the likelihood of hypovolemia and/or hypoxia and should increase your suspicion that the casualty will have an altered mental status.

The initial rapid assessment of a casualty’s mental status comes from communicating with the casualty by asking them to follow commands and to answer questions. If the casualty is not responding appropriately (noticed by observing their verbal and nonverbal responses), this is a sign of an altered mental status. Later in the TTA, during the “H” of head injury evaluation, you will assess them using the AVPU technique. That involves assessing for responsiveness by validating whether the casualty is alert (the “A”), responds to your verbal commands appropriately (the “V”), responds to painful stimulation (the “P”), or is unresponsive (the “U”).