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It is common for an EMS physician to encounter patients experiencing an alteration in their level of consciousness. This can present as a decrease in the level of consciousness in which the patient will exhibit confusion or a more significant alteration to the point of coma. An individual may also present with acute agitation, confusion, and violent and uncontrollable behavior.

Traditionally decreased consciousness and acute agitation are often viewed as separate entities. In reality, both states are divergent points on a continuum. For example, a hypoglycemic patient may be simply confused, comatose, or combative and dangerous. The acutely agitated patient may require restraint and sedation prior to receiving care that may be very similar to that given to a patient with decreased consciousness.

The EMS physician is a tremendous asset in caring for a patient with an altered mental status. He or she brings a breadth and depth of knowledge that will provide a significant differential diagnosis list while having the ability to provide physician level care in the unusual circumstances that require such care.

The purpose of this chapter is to develop an understanding of these altered states, identify causes, and develop treatment plans that can be employed in the field whether a cause is identified or not. This chapter also gives particular attention to the acutely agitated state and the approach and treatment that is required to attempt to prevent a police or EMS provider–related death.

Although an overview of the approach and treatment of the altered state is provided, it must be emphasized that individual conditions may require different or modified treatment depending on the situation.


  • Identification of conditions causing altered level of consciousness.

  • Discuss treatment priorities and plans.

  • Discuss current understanding of excited delirium and treatment.

  • Discuss restraint and takedown techniques.

  • Overview chemical restraint and sedation.


When attempting treatment of an altered patient, provider safety is paramount. Not only must the EMS physician be aware of direct danger from a combative patient, or an unconscious patient who suddenly regains consciousness, he or she must also maintain vigilance to the surrounding scene. Dangerous factors that may have contributed to the patient's condition may still be present. Refer to Chapter 30 for a full discussion on this topic.


There are many potential causes of altered mental status. The classic mnemonic is AEIOU TIPS (see Box 36-1). This provides a concise overview of multiple entities that may lead to altered consciousness. This section will focus on specific conditions that may be identified and corrected in the field setting. This section will also discuss conditions that may require presumptive treatment based on suspicion alone in the absence of field diagnostics.

Box 36-1 Altered Mental Status (AEIOU ...

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