EMS providers are often called to evaluate patients who are behaving oddly or who are having an emotional or mental crisis. Although these conditions are not necessarily all from diagnosable psychiatric disorders, all involve—to some extent—disorders of thinking. These patients are therefore often labeled as “psychiatric,” even if the cause of the patient’s symptoms is from another medical condition.

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  Discuss the initial prehospital evaluation and management of the acutely psychotic patient.

  
  
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  Discuss common psychiatric conditions in prehospital patients.

  
  
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  Discuss the initial prehospital evaluation and management of the suicidal patient.

  
  
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  Discuss the initial prehospital evaluation and management of the homicidal patient.

  
  
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  Discuss commonly encountered drugs of abuse and their toxidromes.

  
  
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  Discuss the involvement of law enforcement in prehospital psychiatric patients.

  
  
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  Discuss some pitfalls associated with these conditions in the prehospital environment.

There are three key points to understanding behaviorally disordered patients. First, patients with odd behavior or who are having a mental or emotional crisis are “real patients.” These patients need capable, caring EMS providers just as much as other patients who are suffering from medical conditions that can be treated with a paramedic drug kit. Providers who dismiss many of these patients as “just another psych patient” not only do not appreciate the varied causes of odd behavior, but may also miss an early opportunity to intervene in a potentially life-threatening condition. Second, these patients often present unique challenges to EMS providers. Since these patients often have impaired reasoning about their situation, they may have difficulty giving a history or answering questions like other patients. This can sometimes be frustrating to providers, especially those who are not used to utilizing creativity in order to obtain information. Finally, patients with impaired reasoning skills in chaotic environments may respond unpredictably. More so than with other types of patients, providers must always be mindful of their own safety as well as for others at the scene.

There are very few studies in the literature that specifically investigate prehospital management of behavior-disordered patients. Many of the recommendations in this chapter, therefore, are taken from the much larger literature on emergency department management of these patients. Nonetheless, prehospital providers are the “eyes and ears” of the clinicians who will eventually be treating these patients in the emergency department and will be the ones offering early intervention, which is key in the management of these patients.

Behaviorally disordered patients are common in the prehospital setting, although not all conditions have a definable psychiatric diagnosis. Such conditions include agitation and acute psychosis, suicidal patients, and homicidal patients. These conditions are often called presentations or syndromes, as each is only a label for symptoms which are produced by a variety of medical conditions. Each of these syndromes is discussed in turn.

AGITATION AND ACUTE PSYCHOSIS

Agitation and acute psychosis are challenging to specifically define. Most definitions include a disturbance or disorder in thinking with resulting excitement or restlessness on the part of the patient. Most providers “know agitation when they see it.” Remarkably, however, most have difficulty defining agitation precisely. Likely this is because individual providers often have different comfort levels with restless or excited patients; an agitated patient to one provider may simply be an irritable or ornery patient to another.

Agitation experts, on the other hand, have defined agitation not as a diagnosis but rather as a collection of poorly defined symptoms. These symptoms usually involve some actions by the patient which cause some temporary disruption in the ability to care for that patient.¹ This can result from a primary psychiatric disorder, a medical condition such as low glucose or low blood oxygen, a metabolic disturbance or infection, thyroid disorder, substance use, head injury, or any other condition which impacts the function of the brain. Importantly, however, agitation also involves violence or the potential of violence, not just simply disregarding or resisting the following of instructions in the field.

Since agitation is difficult to define, it is also somewhat difficult to measure. Overseas, broadly defined psychiatric emergencies account for 12% of all EMS calls.² Inside the emergency department, providers diagnosed “mental disorders” more than 4 million times in 2006.³ Based on these numbers, EMS providers do and will likely to encounter agitation or psychosis-related calls quite frequently. With challenges in funding of the public mental health system, these encounters are likely to grow in number.

Safety is the primary concern in the approach to the agitated patient. Agitated patients who attract police and EMS attention are usually already fairly excited or restless. In these patients, approaching lights and sirens or loud voices may escalate an unstable situation into a chaotic one. Providers should always be mindful of their own safety, as well as that of their partners and others at scene, when approaching these patients. In general, the safest initial method of approach to a behaviorally-disordered patient is verbal, as this can be done from a safe distance.⁴ Ideally, one person should establish verbal contact with the patient so as to keep extra noise to a minimum.⁵ Remember, most people—including patients—do not like it when multiple people are talking to them loudly at once, so try to avoid this if at all possible. Start the conversation by stating your name and asking the patient’s name. Attempt to find out why the patient is agitated. The answer you get to this question can reveal a surprising amount of information. “I’m in pain,” “I just broke up with my partner,” or “There are Martians chasing me” all involve different issues that need to be addressed. They also usually have different treatments.

While conversing with the patient, personal safety is still paramount. Care should be given to respecting the patient’s personal space and to remaining at least 2 arm lengths of distance from the patient. If the encounter is at night, responders should leave even more space so that sudden moves in the darkness to do not lead to compromised safety. Shining the flashlight directly in the eyes of the patient should be avoided as it may cause increased agitation/anxiety. The patient’s behavior may be motivated by fear and calming their fears if possible is preferable to escalating them. These verbal techniques will often be so effective that patients can be willingly led to the quieter environment of the ambulance.

Sometimes, patients are so agitated that verbal communication is difficult if not impossible. In these instances, patients may need to be forcefully restrained. These events are high-risk, anxiety-provoking patient encounters, with a risk of injury to the patient as well as the provider. Given this, forceful takedowns are a last resort option after verbal de-escalation has failed. In general, these forceful takedowns are ideally performed primarily by law enforcement. EMS providers should avoid utilizing force without proper specialized training in takedown techniques or without the advantage of enough manpower (ie, overwhelming force).

Once the patient is calmed or subdued, assessment is the next step. If the patient continues to struggle against maximal restraint, medication can be used to further calm the patient (see Table 51-1). In most prehospital situations, the cause of the agitation is typically not known for certain, and so benzodiazepines are usually the first-line medications. Unless you are certain that the patient will need a long-acting medication, the shortest-acting benzodiazepine possible should be administered and will be based on local protocols and practice. See Table 51-1. The dose should be enough to calm the patient, not put them to sleep, as it will be difficult to assess a nontalking, overly sedated patient in the emergency department and oversedation often leads to additional unnecessary studies, like CT scans, to evaluate why the patient is so sedate and nonconversant.

The differential diagnosis of agitation is wide, including substance intoxication, substance withdrawal, electrolyte disturbances, thyroid dysfunction, brain injury, dementia, or psychiatric disorders such as schizophrenia. Clues from the scene and the patient’s vital signs are therefore particularly important. Are there any injuries on the patient that might be causing agitation, particularly around the head? Are there any signs at the scene, such as needles or alcohol bottles that might provide clues?

Although it is often tempting to blame the patient’s symptoms on “just psych,” this should be the last diagnosis that EMS providers should consider. Always check both an oxygen saturation and a finger-stick glucose level, as these are easily correctable causes of agitation. Beyond this, there are a few considerations which can help further distinguish between psychiatric and medical causes of agitation (Table 51-1).

If the answer to any of these questions is yes, there is an especially strong likelihood that the patient may have a medical cause for their condition. Remember, however, that even patients with psychiatric disorders can get medical illnesses. It is probably safest to assume, therefore, that all patients with agitation have another cause for their symptoms until proven otherwise.

EXCITED DELIRIUM SYNDROME

Agitation that is so severe that it can cause sudden death is termed excited delirium syndrome (ExDS). ExDS, also known as agitated delirium, is a combination of altered mental status and combativeness.⁶ Experts have debated the precise definition of ExDS in the literature, but there is general agreement that symptoms include tolerance to significant pain, rapid breathing, sweating, severe agitation, elevated temperature, poor awareness of police presence, lack of fatiguing, unusual or superhuman strength, and inappropriate clothing for the current environment. Not all of these signs or symptoms need to be present to diagnose ExDS. ExDS represents a true medical not psychiatric emergency. The diagnosis is often challenging, because the clinical signs and symptoms of ExDS can be produced by a wide variety of disease. Agitation, combativeness, and altered mental status, for example, can be produced by hypoglycemia, thyroid storm, certain kinds of seizures, cocaine, or methamphetamine use.

Prehospital personnel will not generally be able to differentiate between the multiple possible causes of ExDS. Instead, EMS personnel should simply recognize that the patient has a more severe agitation than is typical and symptoms consistent with ExDS. Especially if this agitation is unresponsive to agitation medications (see Table 51-2), these patients have a real medical emergency. High doses of sedating medications are often ultimately required, and initiation of therapy should begin in the field. All such patients will require transfer to an emergency department (ED) for further management and evaluation.