Patient-related factors

A host of risk factors specific to the patient have been found to bear on the likelihood of future violence. These patient-related variables can be categorized into two major groups: (1) dynamic factors, such as acute clinical presentation, and (2) static factors, such as patient history, demographic features, and enduring character traits.

Clinical experiences inform us that acute clinical presentations are more likely to respond to clinical interventions than well-established static factors. McNiel et al. found that the strongest predictive relationships for aggression in the acute setting were obtained from clinical risk factors rather than historical risk factors [12,13].

Studies show that most inpatient violent outbursts do not arise abruptly, but occur after a period of escalating agitation or other change in behavior [5]. Psychomotor agitation is an established short-term risk factor for physical aggression. Acute behavioral cues often observed prior to violent incidents include boisterousness, irritability, confusion, attention-seeking behavior, and increased motor activity [5,14–16]. Threatening behaviors are often reported prior to aggressive acts; such behaviors include posturing, throwing objects, attacking or destroying property, self-harming behaviors, and direct verbal and physical threats [17], among others [18]. Some reports have identified changes in mental states including anger [19] and anxiety (75% of reported cases) [20] as antecedents to violent incidents. Triggers for violence may be highly individual, but stressors commonly associated with violence include being forced to take medications and involuntary hospitalization itself [9,21].

Static variables, including history, age, gender, and diagnosis, are well-established predictors of violence over the long term [22,23]. History of previous violence remains a vigorous static predictor of future aggression throughout most literature [24]. However, other static variables, such as sex, age, and alcohol abuse, seem to play a lesser role in acute inpatient settings, while current clinical presentation, illicit substance use, and psychopathological variables may be more significant contributors in the short-term [24]. Some studies have concluded that patients with diagnoses of schizophrenia, bipolar disorder, and mental retardation are more likely to engage in violent acts in the hospital setting than are patients with other diagnoses [3,12].

Other static factors associated with increased risk include a history of substance abuse [25–27], brain injury [28], and antisocial and other personality disorders [22,27,29]. Many of these patient-related factors are summarized in Table 6.1.

Staff-related factors

Psychiatric nurses, and staff in general, play a highly meaningful role in shaping patient experience and the social environment on the ward, interpersonally and on a group dynamic level [30,31]. Staff who are psychologically astute and who are engaged with and empathetically responsive to patients can provide a powerful stabilizing influence on patients in crisis and a milieu vulnerable to chaos. Conversely, staff who communicate negative or punitive attitudes to patients may contribute to patients’ frustration or rage [32].

Bowers et al. found that staff–patient interactions precipitate an estimated 40% of aggressive and violent incidents [5]. Staff interventions that may lead to patient violence include limiting patients’ freedom [5,33,34], administering or discussing medications [18,32,34], and placing patients in seclusion or restraints [17,18,35]. Attempts at de-escalating an already agitated patient were also found to precipitate violent outbursts [36]. Engaging in a power struggle has been shown to decrease therapeutic communication and trigger violence [32,33].

Of particular concern, recurrent violence on inpatient units may lead to poor job satisfaction and frank psychopathology in staff. In turn, this may result in negative staff–patient interpersonal interactions and possibly poor patient outcomes [30,31].

Patient–patient factors

Interactions with and reactions toward other patients are often found to contribute to violent incidents. Patient–patient factors include physical contact and/or intrusion into one another’s “personal space” [37,38], competition [19], and retaliation [17,33].

Environmental/unit-related factors

Environmental and unit-related factors have a major role in influencing the risk of violence. Units that are overcrowded [39–41], physically restrictive [42], or inadequately staffed [43] experience higher rates of patient violence, as do those where patients experience either excessive sensory stimulation [34] or lack of stimulation and/or boredom [33,43]. A lack of psychological space, having little privacy, or not being able to spend time alone when needed may be important in triggering aggression [39].

Violence on psychiatric inpatient units appears to fluctuate throughout the day, with the highest incidence of violence occurring during staff shift changes, particularly during the swing shift (3 p.m. to 11 p.m.). Medication times and meal times were also found to be associated with higher incidence of violence [44].

Behavioral management

Staff who are skilled in recognizing behavioral cues are better equipped to preempt and minimize the likelihood of a violent incident occurring. Verbal de-escalation and/or medication administration performed properly have been shown to be effective at reducing rates of containment procedures [59]. These are important findings, as these methods are frequently used in response to violence and aggression. Staff therefore should receive routine, ongoing training in the use of verbal de-escalation techniques and other behavioral management approaches. The American Psychiatric Association (APA) Task Force on Psychiatric Emergency Services recommends yearly training in these methods [60].

The culture of an inpatient unit can be optimized for safety by improving the therapeutic relationship between staff and patients [43]. Patients who feel staff are accessible, listen to and advocate for them, and strive to involve them in treatment planning may be less prone to engage in violence.

Psychopharmalogical interventions

When an acutely hospitalized patient is physically agitated or threatens harm to others, clinicians often attempt to prevent a violent event by administering psychotropic medication on an as-needed basis (prn). Nonscheduled medications are also given acutely after an act of aggression has occurred to reduce time spent in seclusion and/or restraints and to prevent further violence.

Routes of administration, from most to least invasive and fastest onset of action, are intravenous (onset of action 15–30 seconds), intramuscular (20–30 minutes), and oral (60 minutes). Aside from the longer onset of action, oral administration is always preferred. However, intramuscular administration must often be resorted to when an uncooperative patient is in seclusion and/or restraints in order to assure adherence and to expedite release. Intravenous medications are typically only given in medical emergency departments.

A number of parenteral antipsychotic agents are effective in the treatment of psychotic agitation and aggression. The first-generation antipsychotic haloperidol is available in parenteral forms and has been used for decades in community hospitals. An anticholinergic agent (diphenhydramine, benztropine, or trihexyphenidyl) should always be co-administered with haloperidol in order maximize effectiveness [61], to reduce the need for additional medication intervention [62], and to prevent extrapyramidal side effects [63], primarily dystonic reactions. Of the atypical antipsychotics, only olanzapine, ziprasidone, and aripiprazole have intramuscular formulations. They are at least as effective as haloperidol alone (without an anticholinergic agent) in controlling agitation, more effective at controlling aggression [64], and carry a lower side effect burden [65]. In a study comparing the effectiveness of olanzapine and aripiprazole for the treatment of agitation in acutely ill patients with schizophrenia over a 5-day period, both were equally effective, but olanzapine was significantly more likely to increase fasting glucose and triglycerides [66].

Clinicians often use benzodiazepines alone or in combination with antipsychotics to control psychosis-induced aggression and agitation. However, a recent Cochrane Database Review found little research evidence to support this common practice [67]. Comparing benzodiazepines to placebo found little difference on most outcome measures; adding benzodiazepines to antipsychotics did not further reduce agitation and aggression 4 hours after administration, and the combination of haloperidol and midazolam actually increased aggression 12 hours after administration. In an experimental paradigm that was designed to test aggressive responding during a competitive game, male subjects given diazepam were more likely to select higher shock levels for their opponents than those given placebo [68]. Concerns have been raised regarding the safety of concurrent intramuscular administration of benzodiazepines with olanzapine due to the potential for excessive sedation, hypoxia, cardiorespiratory depression, and, in rare cases, death [69]. Benzodiazepines may be best indicated for acute nonpsychotic agitation and aggression.

In 2012, the US Food and Drug Administration (FDA) approved loxitane inhalation powder (Adusave) for the treatment of agitation in persons with schizophrenia and bipolar disorder. Inhaled loxitane results in rapid absorption through the alveoli, and maximum loxitane concentrations are reached in 2 minutes with reduced agitation seen at 10 minutes after administration [70]. Loxitane is non-invasive and simple to administer, but it requires some cooperation from the patient and is not an alternative to intramuscular injection during a psychiatric emergency [71]. Further, inhaled loxitane cannot be used in those with clinically significant pulmonary disease, and facilities administering this drug must be equipped to effectively treat bronchospasm in the event of this potentially serious adverse effect [72].