Epidemiology

Patients with suicidal or homicidal ideation are encountered frequently in the emergency department (ED). Approximately 0.4% of all ED visits in the United States involve suicidal patients, and suicide accounted for 34,598 deaths in 2007 (almost twice the number of deaths by homicide, 18,361), which makes it the 10th leading cause of death overall.¹ For Americans aged 15 to 24 years, suicide ranks as the third leading cause of death.² This age group also accounts for more ED visits for attempted suicide and self-injury than any other age group does. More than 1200 children and adolescents complete suicide annually in the United States,³ and it is estimated that 11 attempted suicides occur per suicide death.¹ More than 40% of individuals 16 years or older who completed suicide were evaluated in an ED in the year before their terminal act.³

Although the rate of attempted suicide was highest in female patients 15 to 19 years old, nearly five times as many males died by suicide in this age group. About six times as many males as females died by suicide in the 20- to 24-year age group, and older, non-Hispanic white men have a suicide rate than is staggeringly higher than the national average for the general population. Of patients with evidence of self-harm, poisoning was the cause of death in 13% of males and 40% of females, suffocation in 24% of males and 21% of females, and firearms in 56% of males and 30% of females.¹ Self-mutilation (by cutting or piercing) was observed in 20% of patients evaluated in the ED for a suicidal gesture. One third of suicidal patients were admitted for inpatient management, one third were transferred to an off-site facility, and one fifth were referred to outpatient psychiatric services.⁴

Intentionally harmful behavior also constitutes a growing problem in children, adolescents, and young adults. It has been estimated that the prevalence of mental illness among youth in Canada and the United States approaches 15% to 20%, with an anticipated 50% increase by 2020. Pediatric mental health complaints account for 1.6% of all annual ED visits in the United States and 1% of all annual ED visits in Canada.^2,5

Homicide ranks as the most common cause of death in black males 15 to 24 years of age and is the second leading cause of deaths for all youths in this age group. In 2005 alone, more than 5000 deaths by homicide occurred in this age group, and in 2006 this age group received medical care for more than 750,000 cases of nonfatal violent injury.⁶

A focused risk assessment is the primary objective for the emergency provider caring for a patient who is threatening harm to self or others. Risk assessments vary widely, depending on the circumstances of the patient, comorbid disease, mental status, and other social issues. The main challenge to effective risk assessment is the lack of a specific diagnostic test to stratify threat in suicidal or homicidal patients. No interventional test is currently available to determine who is at greatest risk for injury—data for risk stratification come from psychologic autopsy, which is the study of patient characteristics in completed suicides. Predictive data for outcomes of these patients after ED evaluation are lacking. This chapter focuses on the directed examination and evaluation of patients who pose threats of harm to self or others.

Pathophysiology

Numerous factors influence the likelihood of self-harm, including depression and other mental disorders, alcohol or substance abuse, separation or divorce, physical or sexual abuse, and significant medical conditions such as human immunodeficiency virus infection, cancer, and dialysis-dependent renal failure (see the “Red Flags” box). Previous suicide attempters also have more concurrent general medical conditions, alcohol or substance abuse, work hours missed, and current suicidal ideation than do nonattempters.⁷ More than 90% of people who die by suicide have a mental health disorder, a substance abuse disorder, or both.¹ Depression is a significant and common risk factor to address because one in three patients encountered in the ED have moderate to severe depression. In adult male ED patients, depression is more strongly associated with the likelihood of perpetrating violent behavior than excessive alcohol consumption is.⁸

Besides the presence of risk factors, poorly understood biologic factors probably influence self-harm. Serotonin levels have been studied in suicidal patients, and data suggest that lower levels of cerebral 5-hydroxyindoleacetic acid (a serotonin metabolite) are found in patients who attempt suicide.^9–11 Increasing serotonin levels through pharmacotherapy with drug classes such as tricyclic antidepressants or selective serotonin reuptake inhibitors is a common treatment of depression and suicidal ideation.

Presenting Signs and Symptoms

Patients may seek treatment in the ED after considering or attempting to harm themselves or others. These actions range from unsuccessful, yet serious gestures to the use of suicidal ideation for secondary gain. Clinical suspicion should always be high, and patients’ complaints must be taken seriously. Careful, open-ended, nonjudgmental questioning can help discern the level of risk by understanding the patient’s intent.

In addition, emergency physicians should be cognizant of interactions with adolescent patients and consider screening either formally or informally for suicidal ideation. A recent study evaluated the feasibility of screening nonpsychiatric patients for suicide risk and targeted patients between the ages of 10 and 21 years. In this study interval, 37 of 50 patients with psychiatric complaints screened positive for suicide risk. However, 27 of 106 patients evaluated for nonpsychiatric complaints also screened positive for suicide risk. Each of the patients underwent formal psychiatric consultation, and none of the patients with nonpsychiatric complaints warranted hospitalization but were provided with available outpatient psychiatric services. Interestingly, screening of nonpsychiatric patients did not increase the overall length of stay.³

Injured patients with a concerning mechanism (ingestion, single-person car accident, fall) should be screened for suicidal ideation and intent. If an attempt is uncovered, the provider should solicit the patient’s feelings about survival. It is important to understand why patients survived as a predictor of immediate or ongoing risk for harm. The following questions should be considered:

A practice guideline of the American Psychiatric Association summarized large amounts of retrospective data regarding risk factors in patients who committed suicide.¹² The relative importance and clinical utility of such risk factors can be challenging, however. Seemingly innocuous patient data may represent significant risk, as evidenced by studies demonstrating a higher suicide rate in women who received breast implants.¹³ Such epidemiologic studies are difficult to translate into clinical practice, but they do provide an understanding of the complexity of risk stratification in suicidal and homicidal patients.

Differential Diagnosis and Medical Decision Making

The differential diagnosis of self-harm includes minor depression, major depression, suicidal ideation, suicidal gestures, and suicidal attempts of varying lethality and intent. Other alternative diagnoses can be difficult to establish in the ED. One such alternative is the threat of suicide for secondary gain; very little is written or researched about patients with such intents. The goal of secondary gain is often hospitalization to avoid incarceration, legal prosecution, homelessness, or other social problems. A second alternative diagnosis is intentional self-mutilation, such as cutting or hair pulling. This is differentiated from suicidal ideation by its nonlethal intent and frequency of the behavior. Self-mutilation is believed to be a maladaptive response to stress.

Diagnostic Testing

Diagnostic testing in patients with threats of harm to self should focus on the mechanism of the suicidal attempt and any significant comorbid disease (including alcohol and drug abuse). Specific testing may help in evaluating certain treatable ingestions, such as acetaminophen or salicylates; in many cases, however, no specific testing is required. Imaging should be ordered appropriately for patients whose harmful actions involve jumping, hanging, or other traumatic injuries. Screening laboratory tests may be required to arrange for transfer or admission to a psychiatric facility, although such testing has little diagnostic value in the ED evaluation and treatment of suicidal or homicidal patients.¹⁴

Treatment

Patients who have attempted suicide must be evaluated immediately to determine the lethality of the reported or suspected method of harm. Once the threat assessment is complete, the patient should be placed in a closely monitored setting. Physical or chemical restraint and suicide precautions may be required in certain circumstances. Suicide precautions include undressing and gowning the patient, removal of potential weapons or harmful items, one-on-one or video supervision, and security escort for travel and transfer. Careful questioning and examination of the patient should establish the level of risk and cooperation.

All 50 states provide the physician the ability to commit any individual who is a threat either to self or to others or who is unable to care for himself or herself. This psychiatric hold is time limited (usually 72 hours) to permit emergency evaluation and treatment of the patient. The specific actions and documentation required to commit a patient vary by state jurisdiction. Adherence to the process is very important, and the decision to act should be made with appropriate gravity. Documentation of the reason for committal should be provided in clear detail, and supplementary historical information from family, police, or others should also be included in the chart.

Tarasoff v. Regents of the University of California was a landmark legal decision in 1976 that established an obligation by the health care professional to warn a specific individual at identifiable risk for harm, thus overriding the patient’s confidentiality. To fulfil this obligation, both the threatened individual and the police must be informed of the intentions of the homicidal patient. Patients who have an intention to hurt or kill an identifiable individual should be committed and evaluated by a psychiatrist. Discussions with legal and psychiatric colleagues should clarify who will perform any required notification.

Contracts for safety are pacts that include a patient’s promise to seek immediate evaluation should thoughts of violence or self-harm increase. Current American Psychiatric Association guidelines do not recommend contracts for safety in emergency situations,¹² although such understandings should be reinforced with any patient who is discharged after psychiatric evaluation in the ED.

Disposition

Once the initial challenges of medical assessment have been met, the practitioner should determine the safest and most appropriate disposition for the individual patient’s social condition (Fig. 196.1). Psychiatric consultants often aid in the necessary evaluation, admission, or follow-up of at-risk patients. If the clinician has significant concerns, the patient should be admitted or transferred to an appropriately safe inpatient setting. Patients may need to be committed for involuntary psychiatric admission if they are not willing to sign in voluntarily.

Fig. 196.1 Algorithm for the evaluation and treatment of suicidal or homicidal patients.

One prospectively validated tool that is valuable for use in the ED is the Modified SAD PERSONS Scale developed by Hockberger and Rothstein in 1988 (Table 196.1). The scale uses a series of criteria that allow easy review of risk factors and assist in the identification of conditions that should prompt admission. Patients with a low score are less likely to have adverse events.¹⁵ However, patients testing positive for anxiety and hopelessness with concurrent depression are at increased risk to commit suicide.⁷

Table 196.1 Modified Sad Persons Scale of Hockberger and Rothstein: Based on the SAD PERSONS Mnemonic

^* The score equals the points for all 10 parameters: minimum score, 0; maximum score, 14. The higher the score, the greater the risk for suicide. A patient with a score of 5 or less rarely requires hospitalization.

Adapted from Hockberger RS, Rothstein RJ. Assessment of suicide potential by non-psychiatrists using the SAD PERSONS score. J Emerg Med 1988;6:99–107.

As evidence suggests from multiple studies, the following four items have also demonstrated high sensitivity and specificity for predicting suicidality in adolescents:

For homicidal patients or victims of violent injury, it is incumbent on the provider to assess the risk for retaliatory violence. Because retaliation often occurs in the weeks immediately following an incident and commonly involves firearms, the following screening questions (known as the “FiGHTS” mnemonic) may aid the ED clinician in determining an adolescent’s risk for carrying handguns:

A positive screen for suicidal or homicidal ideation or intent should prompt further evaluation and management, but patients may be discharged home if they are deemed safe after medical evaluation and psychiatric consultation (Box 196.2). Among patients discharged from the ED, significant predictors of return visits within 30 days include lack of a caregiver at the time of discharge and a history of a previous suicide attempt.¹⁸ A treatment plan, return precautions, and conditions for safety should be clear, well documented, and understood by all parties involved (including friends, family, and caregivers of the patient, especially when children or adolescents are involved).