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<< The Violent Patient: Clinical Management, Use Of Physical And Chemical Restraints, And Medicolegal Concerns

Emergency Department Evaluation

Medical Clearance

An important aspect of the ED evaluation is the so-called "medical clearance." Medical clearance refers to the process of screening a supposedly "psychiatric patient" for medical illness. Patients who are medically cleared may then be evaluated by psychiatry, the assumption being the patient has no acute medical problem. However, many patients with apparent psychosis have an acute medical problem, while other patients with a known psychiatric diagnosis have a superimposed organic disease. In one study, 4% of patients evaluated for psychiatric complaints in the ED required acute medical treatment within 24 hours of psychiatric admission. 41 Deficiencies in the history and physical examination accounted for the vast majority of missed illness.

Only after performing the appropriate history, physical examination, and indicated diagnostic testing may a physician "medically clear" an agitated patient. The emergency physician has a responsibility to guarantee the absence of organic illness before arranging disposition to a psychiatric or police facility. Failure to do so is a breach of duty to the patient and leaves the physician open to claims of negligence.

Risk Assessment

Identification of potentially violent patients is not an exact science. However, male gender, a prior history of violence, and drug or alcohol abuse are the best positive predictors of violence in the ED.26,42-44 Other high-risk patients include those with psychiatric illness, altered mental status, and those in police custody.45 Ethnicity, diagnosis, age, marital status, and education are unreliable predictors of violence.46

Violence rarely erupts without warning. Frequently, physical aggression follows a period of mounting tension. The patient will give both verbal and nonverbal cues that signal an imminent attack.19 In a typical scenario, the patient first becomes angry, then resists authority, and finally becomes confrontational and overtly violent.19

Patient observation is the first step in predicting potential violence. In the ED, an angry patient should be considered potentially violent. Increased motor activity is one of the most consistent signs of impending attack. Provocative behavior, an angry demeanor, pacing, loud speech, tense posture, frequently changing body position, pounding walls, or throwing things are all signs of impending violence.3,6

While the emergency physician should remain alert to these cues, violent behavior may indeed erupt without warning (especially in patients with acute medical illness). The clinician should not feel overly confident in his or her ability to sense impending danger.47 In one study, psychiatrists were only 60% sensitive and 58% specific in their ability to predict violence overall, and were even less accurate regarding violence by women.48 Still, many authorities suggest that the clinician "listen to their gut" regarding a potentially dangerous situation.4,49


Remove the angry patient from contact with other patients.49 If identified at triage or in the waiting room, bring them directly to a treatment room, as waiting times correlate with violent behavior.7,50 Although this practice may violate typical triage protocols, the potentially violent patient requires urgent intervention to prevent  escalation. Often, this preferential treatment will defuse patient anger.


Security should disarm all potentially violent patients before the interview. Metal detectors can be used for this purpose before the patient enters the treatment area. The practice of undressing all patients and placing them in a gown is useful to search for weapons in a non-confrontational manner. The hospital gown also permits easy identification in the event the patient elopes from the ED. Some weapons are designed to appear as innocuous objects, such as a knife made to look like a pen or a dagger built into a belt buckle. A razor blade taped to a credit card is unlikely to be detected on a cursory search. While searching for weapons may appear to violate privacy, a recent study showed that routine disarming of all patients presenting to the ED results in a feeling of increased safety for both patients and staff.46

Interviewing The Patient

The room where the patient is interviewed should be private but not isolated.4,20,47 ACEP guidelines recommend that most EDs contain at least one secure examination room with shatterproof ceiling lights, a solid ceiling, heavy, indestructible chairs, a well-secured restraint bed, two doors that can be locked from the outside, and an emergency distress button that can be activated unobtrusively. 51 Ideally, two exits should be available (one escape route for the physician, another for the patient), and
doors should swing outwards.

The room should not contain heavy objects that may be thrown, such as ashtrays,52 or other potential weapons, such as electrical cords, scalpels, needles, or hot liquids.53 An alarm system is essential. The emergency physician should have a mechanism for alerting others that he or she is in danger, such as a panic button or a code word or phrase that alerts security (e.g., "I need Dr. Armstrong in here").52

The patient and interviewer may be seated roughly equidistant from the door,47 or the interviewer may sit between the patient and the door.52 Blocking the door, however, poses a theoretical risk to the clinician if the patient feels the need to escape.53 On the other hand, a physician who is trapped in the room with a violent patient is at high risk for injury. The clinician should have unrestricted access to the door and should never sit behind a desk.49 Have security nearby and leave the door open to allow both intervention and escape.

For personal protection, remove glasses, earrings, and necklaces, and tuck neckties into shirts.4,52 Remove any personal accessories that may be used against you, such as a stethoscope, scissors, or pocket knives.53 Be aware of any objects within the room or on the patient's body, such as pens, watches, or belts, which may be used as weapons.52

De-escalation Techniques

The patient should be made as comfortable as possible, and the interviewer should adopt an honest and straightforward manner.54 In some cases, an agitated patient may be aware of his or her impulse control problem and may welcome limits set by the clinician. The physician can state, "I can't help you when you threaten me or the ED staff."54

Act as a friendly host to establish trust.47 Offer patients a soft chair or something to eat or drink. However, never serve a hot liquid like coffee, as it may be thrown on the physician. In upscale EDs, iced cappuccino is the preferred beverage—decaffeinated, of course.

Be an attentive listener without conveying weakness or vulnerability.47 The interviewer should not be confrontational. Respond verbally in a calm and soothing tone of voice. Inappropriate responses to a potentially violent patient represent a challenge. Don't force patients to "prove themselves." Arguing, machismo, condescension, or commanding the patient to calm down can have disastrous consequences. An open threat to call security personnel also invites aggression. Do not engage in a shouting match, and avoid direct eye contact or "staring the patient down."

A primary rule in dealing with the potentially violent patient is "no surprises." Do not approach the patient from behind, and do not make sudden movements.4,54 Never, ever touch the violent patient before asking them (except during a restraint situation). When positioning yourself during the interview, stand at least an arm's length away.

A key mistake when interviewing such a patient is failing to address violence directly.42 Ask the patient relevant questions, such as, "Do you consider yourself a fighter?" or "Do you carry a gun?" Stating the obvious (e.g., "You look angry,") may help the patient share their feelings. If the patient becomes more agitated, speak in a conciliatory manner and offer supportive statements,  such as, "You obviously have a lot of willpower and are good at controlling yourself."49,54 If this is not successful, an offer of medication may prevent further escalation.

The clinician must be aware of his or her own reactions to the patient and must avoid showing anger toward the patient (countertransference).47 Most importantly, do not deny or downplay threatening behavior, as this may increase the risk of injury. A chilling illustration of this principle involves a psychiatrist who was killed after entering the waiting room with a patient he knew was potentially violent and armed. He mistakenly assumed that the strength of their physician-patient relationship ensured his personal safety.42

The physician's level of experience may not decrease the incidence of violent behavior.42 All threats should be taken seriously to prevent assault and injury.

If verbal techniques are unsuccessful and escalation of violence occurs, excuse yourself from the room and summon help via a predetermined code word or panic button.

History And Physical Examination

The history and physical exam provide essential clues to an organic cause of agitation. The history is of special importance. In one retrospective study of patients who presented to an ED with psychiatric complaints, history, physical examination, vital signs, and laboratory testing had sensitivities of 94%, 51%, 17%, and 20%, respectively, for identifying a medical problem.55

Certain aspects of the history and physical examination are particularly valuable in determining an organic etiology. Acute onset of agitated behavior points toward a medical problem, as does age of onset. Functional disorders rarely present after the age of 45 years. Assume a medical cause of agitation in an older patient without psychiatric history, until proven otherwise.54,56 Typically, the patient who is agitated due to an organic etiology will be confused and mentally slow, with cognitive deficits.54,56 The speech may be slurred, visual hallucinations present, and vital signs abnormal. Remember that most psychiatric patients are alert and oriented and have a past psychiatric history. (See Table 2.) Four screening criteria—disorientation, abnormal vital signs, clouded consciousness, and patients older than 40 years with no previous psychiatric history—will identify most patients with organic illness.57


The history of present illness should include psychiatric, medical, family, and social information. Ask about medication use and any recent changes to prescribed medications. The familiar ED refrain, "Don't give me Haldol!" is an important clue to prior psychiatric encounters.

Because the agitated patient may not be a reliable source, family and friends can provide valuable information. 47 When available, they should be interviewed independently from the patient. Medical records may detail medical and psychiatric history as well as prior history of violence. Drug and alcohol use is an important part of the history, as substance abuse is highly correlated with violent behavior.

Mental Status Examination

The mental status examination is an essential part of the physical evaluation. The components generally include:

  • General appearance
  • Alertness (level of consciousness)
  • Orientation (person, place, and time)
  • Mood (happy, sad, etc.)
  • Affect (flat, normal, labile, appropriate, inappropriate)
  • Memory (immediate, short-term, long-term)
  • Thought content (delusions, obsessions, suicidal or homicidal ideations)
  • Hallucinations (visual, tactile, auditory, olfactory)
  • Attention and concentration
  • Speech (pressured, slurred, disorganized)
  • Judgment
Physical Examination

If the patient is unrestrained and potentially violent, ask his or her permission to perform a physical examination. In some cases, patient restraint may be necessary to accomplish even the most rudimentary exam.

Perform a thorough physical exam to search for a cause for violent behavior as well as any signs of trauma sustained through violence. The importance of obtaining routine vital signs, especially temperature, cannot be overemphasized. Vital signs provide essential clues to serious medical conditions.

What is the most important vital sign in the agitated patient? Let us phrase the question differently: What vital sign is never present on the chart of an agitated patient? The answer is the same—the temperature. While a rectal temperature may be a dangerous maneuver on an unrestrained paranoid schizophrenic, some attempt to measure temperature must occur before medical clearance. The presence of a fever in conjunction with altered mental status is an ominous sign and may signal a life threat such as sepsis or druginduced hyperthermia.

Observe the patient's general appearance to evaluate nourishment, toxicity, diaphoresis, respiratory distress, and signs of trauma. Remain alert to the characteristic odors of alcohol, ketones, or hydrocarbons. Skin findings may reveal the presence of needle tracks or petechial rash. The clinician may also note specific toxidromes, such as anticholinergic, sympathomimetic, or cholinergic. (See Table 3 and Table 4.)

The neurologic examination deserves special attention. Findings of dysarthria, ataxia, nystagmus, and abnormal pupils implicate an organic etiology for the violent behavior.19,47 Vertical nystagmus is classic with phencyclidine (PCP) intoxication, a frequent cause of violence in urban areas. Despite its central role in distinguishing psychiatric from medical illness, the neurologic examination is frequently neglected during medical clearance.41

Diagnostic Studies

Clinical findings will direct further diagnostic testing. The presence of a prior psychiatric history is an important factor that determines the need for diagnostic testing.

Patients with a psychiatric history and a normal physical examination do not need routine diagnostic tests. In one ED study, history and physical examination alone without universal laboratory testing would have missed only two asymptomatic patients with mild hypokalemia.55

On the other hand, most alert, adult patients with new psychiatric symptoms have an organic etiology. In a prospective study of 100 consecutive, alert patients, 16 to 65 years old, with new psychiatric symptoms evaluated in the ED, 63% had an organic etiology for their symptoms.58 The authors recommended SMA-7, calcium, CPK (if myoglobinuria is possible), alcohol and drug screens, computed tomography scan, and lumbar puncture as part of the medical clearance of these patients. In their study, the medical history was significant in 27 patients, physical examination in six, CBC in five, SMA-7 in 10, CPK in six, alcohol and drug screen in 28, computed tomography scan in eight, and lumbar
puncture in three.

Other authors have suggested a variety of diagnostic tests in the evaluation of the patient with agitated behavior. Perhaps the most important test is a rapid glucose determination. The following tests may be useful on a selected basis:19

  • Arterial blood gases
  • Complete blood count
  • Electrolyte panel
  • Hepatic function tests
  • Toxicology panel
  • Alcohol and toxic alcohols
  • Serum osmolality
  • Specific medication levels
  • B12 and folate
  • Thyroid panel
  • Infectious disease tests
  • Urinalysis
  • EKG
  • CSF analysis
  • CT scan/MRI
  • Plain x-rays
  • EEG


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Last Modified: 12/12/2017
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