Epidemiology

Recent estimates place mental health disorders as one of the three leading causes of total burden of disease and injury in Australia, alongside cancer and cardiovascular disease.^4,5,6 In middle age, it is the leading cause of non-fatal disease burden in the Australian population. There is no doubt that mental health disorders have a high prevalence, are disabling and are high cost in both human and socioeconomic terms.^4,5

In terms of disability, it has been estimated that having moderate to severe depression is the equivalent of having congestive cardiac failure,⁶ chronic severe asthma or chronic hepatitis B.⁵ Severe post traumatic stress syndrome was comparable to the disability from paraplegia and severe schizophrenia was comparable to quadriplegia, in terms of disability.⁵ Over the last 10 years emergency department (ED) presentations have risen 8% in the USA, whereas mental health presentations for the same time period have risen 38%, contributing significantly to ED overcrowding.⁷ This trend has been mirrored in Australia.

Contributing to this may be:

The Australian Institute of Health and Welfare report into Mental Health Services in 2007 estimated that there were over 190 000 occasions of service to Australian EDs where the primary problem was thought to be due to a mental health disorder. This was estimated to be approximately 3.2% of total presentations to public hospital EDs.⁴ This correlates well with other studies and US figures, which estimate 2–6 % of emergency medicine presentations are primarily due to mental health disorders.^1,7,8,9

Two-thirds of these people are between the ages of 15 and 44 years (compared to 42% for the general population presenting to a suburban ED. 29% have anxiety and neurotic disorders, 21% mental and behavioural disorders due to psychoactive substance abuse, 19% mood disorders and 17% schizophrenia or delusional disorders.⁷

This, of course, is a gross underestimate of the prevalence of mental health disease in the ED as many patients remain undiagnosed, and many have active medical conditions and a mental health diagnosis may be secondary.⁸

It is estimated that 17.7% of adult Australians admitted to hospital report a mental health issue in the previous 12 months. An estimated 0.4–0.7% of the adult population suffer from a psychotic episode in any one year.⁵ Mental health issues are highly prevalent and relevant.

Introduction to the mental state examination

The mainstreaming of mental health patients into general EDs has brought problems and anxieties for staff. Staff often feel a lack of confidence because they are dealing with a population of patients unfamiliar to them. They also feel inadequate due to poor assessment skills.^9,10

Mental health patients are often seen as ‘low yield’, unrewarding and there is often a negative attitude expressed toward them.^9,10 A high proportion have drug and alcohol intoxication. This confounds the evaluation and treatment, lengthens the stay of these patients within the ED and delays their disposition. Mental health patients are sometimes perceived as ‘frequent flyers’ – victims of chronic disease that can never be cured – and can be seen as burdensome and unrewarding.

These negative attitudes have resulted in mental health patients being assigned lower triage categories and longer waits to be seen by staff than mainstream patients. They have a higher chance of leaving before assessment has begun or is complete and the overall increase in length of assessment time has the potential to increase violence in the ED.^9,10

With this in mind, there has been much work over the last 10 years on the assessment of mental health patients in a general ED.

ABC of the MSE

A mental state examination (MSE) is analogous to the management of severe trauma. There is an initial risk assessment looking for immediately life-threatening risks to the patient or staff. The triage nurse and the treating doctor should then obtain a brief collateral history from the emergency services or carers, and initial management is based on this assessment. Regardless of threat, all assessments should balance the safety of both patient and staff with privacy and dignity.⁹

Assessment should be based on:²

• appearance and affect

• behaviour

• conversation

• drug and/or alcohol intoxication.

If the situation is relatively controlled, the formal mental health assessment should then take place. Further information is gathered from the community. A provisional assessment and management plan is developed in conjunction with the mental health team, and appropriate disposition is arranged (Fig. 20.1.1).

Fig. 20.1.1 The mental health assessment process.

Triage

The Mental Health Triage Scale (Table 20.1.2) has been developed and modified to be included into the Australian Triage Scale (ATS).^3,9,11 It is very broad and asks the triage nurse to make four assessments: risk of suicide/self harm, risk of aggression/harm to others, risk of absconding and whether the patient is intoxicated. From this, the triage nurse determines the ATS and urgency of initial treatment. It is also helpful to determine if the patient is known to a mental health service.

Table 20.1.2 The Mental Health Triage Scale

ATS 2	Patient is violent, aggressive or suicidal, or is a danger to self or others
	Requires police escort/restraint
ATS 3	Very distressed or acutely psychotic
	Likely to become aggressive
	May be a danger to self or others
ATS 4	Long-standing or semi-urgent mental health problem and/or has supporting agency/escort present
ATS 5	Patient has a long-standing non-acute mental health disorder but has no support agency
	Many require referral to an appropriate community resource

Many centres have developed a triage risk assessment proforma. For ease of use, many of these have included ‘tick box’ areas. A compilation of multiple assessment tools used throughout Australia is shown in Tables 20.1.3, 20.1.4 and 20.1.5.^{1,2,3,5,11,12}

Table 20.1.3 Brief screening suicide risk template

Mental state	Active disease
	Depression
	Psychosis
	Hopelessness/despair/guilt/shame
	Anger/agitation
	Impulsivity
Suicide attempts/thoughts	Continual/specific thoughts
	Formulated plan
	Intent
	Past history of attempt with high lethality
	Means
	Suicide note
	Risk of being found
	Organizing personal affairs
Substance abuse	Current misuse
Supports	Lack of or hostile relationships
Loss	Recent major loss (even perceived): significant relationship, job, housing, financial difficulties, independence
	Recent/new diagnosis of major illness or chronic illness
Patients then stratified into high, medium or low risk

Table 20.1.4 Aggression risk tool

Alert on chart

Previous history of violence/threatening behaviour: verbal or physical

Aggressive behaviour/thoughts

Homicidal ideation

Use of weapons previously

Access to weapons

Intoxicated

Middle aged male

Patient then stratified into high, medium or low risk

Table 20.1.5 Risk of absconding

Mode of arrival

Police

Handcuffed

Family/carer coercion

Voluntary

Past history of absconding behaviour

Alert on chart

Verbalising intent to leave

Lack of insight into illness

Poor/non-compliance with medication

Patients then stratified into high, medium or low risk

It is recommended that any patient who scores ‘high risk’ in any one area or ‘medium risk’ in two areas is treated as a ‘high risk’ patient. Ensuing management of ‘high risk’ patients depends on: local protocols, levels and presence of security, police intervention, restraint and sedation guidelines and guidelines for the urgent assessment by ED and/or by mental health services.

Aims of mental health assessment

The aims of the formal mental health assessment are to determine the following:

Only if all of the above are answered, can management and appropriate disposition be considered.

The formal psychiatric interview

The process of obtaining a mental health assessment is different to that of a general medical assessment. In a general medical history, a series of questions is asked and the response is written. In a mental health assessment, responses are also interpreted. The interviewer is asked to form an opinion as to how thoughts are processed, based on observations. The interviewer is asked to interpret the patient’s thought patterns by what and how the patient tells the interviewer.

Presenting complaint

The patient is asked to recall the sequence of events prior to presentation to the ED. The interviewer should explore the circumstances of the behaviour, reasons for it, degree of planning or impulsivity, and its context. Were drugs and alcohol involved? Was there a recent precipitating event? It is often useful to get the patient to recall the previous 48–72 h leading up to the event.

This usually leads to questioning regarding current difficulties. The interviewer should explore the nature of current problems. They may be financial or legal problems, isolation, bereavement, impending or actual loss, or diagnosis of major illness. Have there been any recent changes and who are their usual support people/person? An exploration of significant relationships is important along with the depth and duration of these relationships. It is useful to explore the patient’s usual coping methods when under stress.

Mood and affect

There should be formal questioning regarding the patient’s mood (internal feelings) and whether it is in keeping with affect (external expression). The mood may be incongruent with affect, swing wildly between extremes (labile) or be completely inappropriate.

Usually mood is assessed by asking about the patient’s ability to cope with activities of daily living such as eating, weight loss or gain, sleep disturbance (early morning wakening or trouble getting to sleep) and general hygiene. The patient’s ability to concentrate may also diminish with increasing mood disturbance, reflected by the ability to perform normal work duties.

This may lead to direct questioning regarding mood and thoughts of suicide. It is important to be direct in asking the patient about suicide and whether they have a formulated plan. A well thought out plan with clear means of carrying out threats is of great concern.

Delusions and hallucinations

Delusions and hallucinations are often personal and the patient may not want to disclose intimate thoughts and beliefs to the interviewer. Hallucinations may be auditory, visual, tactile, olfactory, somatic or gustatory. The context in which they occur should be explored. Hypnagogic (occurring just before sleep) and hypnopompic (occurring on wakening) hallucinations are more benign than others. Common themes for all types of hallucinations include suicide, persecution, religion, control, reference, grandeur or somatization.

Insight and judgement

Insight is the degree of understanding of what is happening and why. This may be:

It is important to determine the patient’s level of insight. This determines appropriate treatment and management, level of supervision required and the likelihood of compliance with treatment.

Introduction

Emergency physicians are facing a significantly increased volume and complexity of mental disorder presentations. Increased numbers relate to increased community care for chronic mental illness, the ageing population and frequent substance abuse. Intoxicated patients, with and without mental disorder, are increasingly being presented to emergency departments (EDs) for assessment due to concerns about patient or community safety. These patients frequently display impulsive, suicidal or violent behaviour and are often difficult to manage. A thorough understanding of the assessment and appropriate disposition of mental disorder presentations is essential for all emergency physicians.

The concept of differentiating an organic from a psychiatric basis for a mental disorder is becoming increasingly blurred as research shows the biological and genetic basis of many traditional psychiatric illnesses. The accepted terminology for classification of mental disorder is also rapidly changing. One accepted Western standard is the Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV).¹ To emphasize the biological basis of many traditional psychiatric illnesses, DSM-IV no longer uses the term ‘organic mental disorder’. Despite this change, current clinical management and disposition still revolve around the traditional distinction of organic (medical) from psychiatric problems.

In practice emergency physicians need a simple classification defining the principal diagnosis of the presenting mental disorder consistent with current DSM-IV terminology. This should assist diagnostic, management and disposition accuracy. Table 20.2.1 is such a suggested classification. A more simplistic grouping into psychiatric, medical, substance-related or anti-social behaviour may even suffice. Correct assignment by the emergency physician to the appropriate classification, and hence appropriate disposition, reduces medical costs and morbidity.²

Table 20.2.1 A simple classification of principal diagnosis of mental disorder for emergency physicians

General approach

Patients with abnormal behaviour labelled as psychiatric after routine medical and psychiatric assessment frequently have a final diagnosis of a medical cause or precipitant for the mental disorder. The incidence of missed medical diagnosis ranges between 8 and 46%.^2–4 A prospective study of ED patients in the USA showed a medical diagnosis in 63% of patients with first psychiatric presentations.⁵ Deciding whether a particular presentation of mental disorder is medical or psychiatric is often difficult, as there are very few absolutes that distinguish medical from psychiatric illness. Careful collection and weighing of appropriate information commonly leads to an accurate differential diagnosis.

Some diagnoses and dispositions can be determined quickly after a medical and psychiatric history, with the addition of a mental state and full physical examination. This may sometimes take place without expensive diagnostic procedures.⁶ Other presentations are difficult and require extensive and intensive evaluation, repeat evaluation, observation in hospital and significant investigations before the diagnosis is clear.

Many initial assessments in EDs are difficult and inaccurate owing to the presence of intoxicating substances or difficult patient factors. The latter may include poor communication ability, poor cooperation with examination, antisocial behaviour, intentional obscuring of information or denial of problems. Intoxicated patients may have other complex and distracting issues, such as threats of violence or self-harm, possible head injury, possible unknown substance overdose, and poor cooperation with necessary history, examination and investigations. A non-judgemental approach with prudent intervention based on known or likely risks, close monitoring in a safe environment, and repeated reassessment of physical and mental state over time are necessary to obtain an accurate diagnosis and optimal outcome.

Studies on medical clearance by ED staff, primary-care physicians and psychiatrists have repeatedly shown a poor ability to discover medical conditions. This failure is commonly due to one or more of the following factors: inadequate history, failure to seek alternative information from relatives, carers and old records, poor attention to physical examination, including vital signs, absence of a reasonable mental state examination, uncritical acceptance of medical clearance by receiving psychiatric staff and failure to re-evaluate over time.⁷ A recent study noted that medical conditions were most easily identified in the ED by the triage nurse or medical officer asking whether any medical conditions existed in addition to the patient’s psychiatric complaints.⁸

Conversely, studies have shown that many patients admitted with a medical diagnosis frequently have a physical presentation of a classic psychiatric disorder. In addition, patients who frequently present to EDs with physical problems commonly have abnormal illness behaviour. Inability to recognize this leads to inappropriate diagnosis and management, with subsequent treatment failure.

Psychiatric patients also have a higher incidence of physical illness than the general population. The comorbid illness may not have been diagnosed previously in this socially disadvantaged population.

Evaluation requires a thorough approach and a commitment of time and effort. Special skills are required for medical clearance and psychiatric interview. A coordinated and focused medical and psychiatric assessment has the highest yield of correct diagnoses.² Proformas may improve compliance and documentation of important details.

Triage

Triage is vital, as many patients presenting with apparent psychiatric problems have medical conditions. The patient previously labelled psychiatric must be carefully triaged to avoid any new medical problems being overlooked. Psychiatric patients have been found to express their physical illnesses in different ways from those without mental illness. They may be suffering from severe or life-threatening illness, but fail to communicate this to their medical carers. Correct identification at the point of entry by nursing staff facilitates correct management and reduces morbidity and mortality.⁹ Many patients with psychiatric illness are also a significant risk to themselves or others, and require urgent intervention. Questions regarding safety should always be raised¹⁰ (Table 20.2.2).

Table 20.2.2 Triage safety questions¹⁰

Nursing staff should use a triage checklist to identify likely organic presentations (Table 20.2.3). These are indications for urgent medical assessment. If these are absent and a psychiatric diagnosis is likely, then an appropriate urgency rating by Australasian Triage Scale for psychiatric presentations should be applied. This triage categorization for psychiatric presentations has been developed and verified, and allows reasonable waiting time standards for urgency to be applied (Table 20.2.4).¹¹

Table 20.2.3 High-yield indicators of organic illness