Introduction

Abnormal behaviour or acute behavioural disturbance is a common presentation to ED. Typically it presents as delirium, aggression and autonomic dysfunction. It poses a particular challenge requiring consideration of the safety of both patient and staff, the underlying process responsible for the abnormal behaviour and the safest and most effective method of managing the situation. Thought must also be given to the medicolegal aspects of managing abnormal behaviour where investigation or treatment is to be carried out against the stated wish of the patient.

1.     Toxins (e.g. alcohol, recreational drug use) or substance withdrawal

2.     Infection (e.g. encephalitis, severe sepsis)

3.     Head Injury/Seizure (e.g. post ictal confusion)

4.     Hypoglycaemia, electrolyte disturbance (e.g. Hyponatraemia)

5.     Hypoxia/Hypercapnia

6.     Psychiatric Illness (acute psychosis/mania)

Mental State Assessment

It is vital to carry out a mental status exam on patients presenting with abnormal behaviour. Appearance, behaviour and speech (coherence, rate, volume) will be apparent from early interactions with the patient. Assessing the patient’s thought content, the presence of any delusions or hallucinations as well as the patient’s insight are essential in directing the management – particularly where capacity may be in question.

Remember the four essential components of capacity – the ability to receive, retain, weigh up and communicate information. All patients should be assumed to have capacity until it has been demonstrated that they don’t. A capacity assessment is performed in regard to a specific decision. Patients may lack the capacity in one area but have capacity in another.

When capacity is in doubt and where there are questions regarding the legal right to prevent a patient from leaving the department, early input from the Liaison Psychiatry team is essential.

Bedside investigations

Venous Blood Gas

Will provide information on acid-base disturbance, PaCO2, Blood Glucose and some electrolytes which may all be causes or contributors to abnormal behaviour.

Urine Toxicology

May be useful in the setting of acute intoxication but beware that the patient’s symptoms may be related to WITHDRAWAL of a substance rather than its presence. Also, urine toxicology may be unreliable as many common drugs (both illicit and prescribed) are not included on point of care testing. There are also a number of agents which can lead to false positives on testing due to cross reactivity and these panels only indicate drug presence not quantity. Instead, assessing for a clinical toxidrome is more useful when considering intoxication as a cause of abnormal behaviour.

Labratory

FBC, U&E, CRP, CK

Helpful in ruling out infection, electrolyte disturbance as a cause. Agitated patients, particularly those who have been subjected to restraint are at risk of rhabdomyolysis so a renal profile and CK are also necessary.

Blood Cultures

If patient is febrile or the underlying aetiology is thought to be infection mediated.

Other

Investigations such as a coagulation screen or serum drug levels (e.g. paracetamol, salicylates) may be warranted depending on findings during patient examination.

Radiology

Used to help determine if there is an intracranial cause of the patient’s behaviour, e.g. space occupying lesion or intracranial haemorrhage. A CT Brain may be warranted if there is evidence of a head injury or if no satisfactory cause of abnormal behaviour is found.

Other

Investigations such chest x-ray or other imaging may be warranted depending on findings during patient examination.

Management

Following initial sedation and assessment, management is then directed by the most likely suspected cause of the patient’s behaviour.

• Further sedation may be required after initiating treatment or while the effect of any intoxicants wear off.

• Clinically stable patients whose abnormal behaviour is purely attributed to intoxication should be observed following sedation until they return to normal mentation and have capacity regarding their ongoing treatment. Those being discharged from the Emergency Department should ideally be discharged to the care of a responsible adult. A referral to medical social work is also warranted for substance abuse counselling.

• Patients with a history of alcohol abuse who present hypoglycaemic should have Thiamine (IV Pabrinex) replacement prior to the administration of IV glucose in order to prevent precipitating a Wernicke’s encephalopathy. Use oral Chlordiazepoxide (Librium) to treat alcohol withdrawal symptoms.

Disposition

Definitive care of these patients can be challenging and often requires input from many teams.

• In the case of infection, intoxicants or metabolic disturbance, the patient should be referred to the on-call medical team.

• Traumatic head injuries should be discussed with the nearest neurosurgical centre for advice on management.

• The liaison psychiatry team should be consulted for patients in whom a primary psychiatric illness is suspected.

• The ICU team should be contacted early in cases where prolonged sedation and airway support are required in which case the patient may need to be managed in an intensive care setting.

 At all times, it is important to consider if the patient has capacity to decline treatment and if treating the patient against their stated wish is in their best interest. Also note that this assessment should be carried out repeatedly as capacity is a dynamic process which may change throughout the course of an illness.