59 - Management

Management

Addictions and substance misuse CHAPTER 4 Drug-­induced excited state A drug-­induced excited state is an under-­recognised and potentially life-­threatening syndrome of agitation, aggression and dysregulated physiological responses.1 Illicit drugs are the most common cause, notably cocaine and New Psychoactive Substances including synthetic ­cannabinoids and stimulants such as mephedrone. There are also other causes of a drug-­induced excited state.2 This section draws attention to the approach required for people whose behaviour presents a danger to themselves or others because of the acute effect of illicit substances, and who are at significant risk of physiological harm. The terms ‘acute behavioural disturbance’ or ‘excited delirium’ are not used because they are not recognised diagnoses and because they are highly controversial terms that are suspected of being misused in respect to deaths in police custody.3–5 Early intervention and de-­escalation are crucial to effective and safe treatment. It cannot be overemphasised that physical restraint should be avoided whenever possible because of the substantial risk to life presented by restraint in these patients. Where restraint cannot be avoided, it should be used carefully and safely: avoiding restraint in the prone position and employing it for the briefest possible time (i.e. for seconds, not minutes). Pathophysiology Various components of the drug-­induced excited state and its treatment (including restraint) lead to disorientation and a ‘fight or flight’ response. The physical exertion employed to ‘escape’ results in hyperthermia and catecholamine release.6 Hyperthermia in turn leads to rhabdomyolysis (with raised creatine kinase)7 as well as worsening delirium.8 Excess sympathetic catecholamines prolong the cardiac QT interval and may adversely affect myocardial function.9 Excess muscle activity, raised catecholamines, hyperthermia and dehydration contribute to a metabolic acidosis and the production of carbon dioxide. This manifests with tachypnoea and may herald pending cardiovascular collapse. It cannot be overemphasised that restraint grossly exacerbates risks in this cascade of events, especially if restraint is prolonged. Identification A drug-­induced excited state is not a distinct diagnosis, but a term used to encapsulate a range of situations in which a person experiences distress, displays agitation or aggression and is at risk of physiological dysregulation. Perhaps the most common symptoms are violent behaviour, increased pain tolerance and constant activity.10 Rapid breathing, a lack of fatigue, hyperpyrexia and tactile hyperthermia are also frequently observed.11 A cascade of events may develop and may be provoked or worsened by restraint, ­leading to increased fear, then protracted physical struggle, hypoxia due to restraint, catecholamine release, lactic acidosis, and so on. Management Verbally de-­escalate and try to ensure environmental safety for the individual and others. It bears repeating that restraint may exacerbate hyperthermia and catecholamine release, worsening outcomes.12 Sedation is important to calm aggression and to reduce