Psychiatric Emergencies and Consultation-Liaison Psychiatry
Core concepts
Risk assessment: suicide (ideation, plan, intent, means, protective factors), violence, self-harm, and vulnerability. Manage the acutely agitated patient with verbal de-escalation first, then pharmacological (benzodiazepines or antipsychotics) and physical restraint only when necessary, with monitoring. Understand suicide risk factors (male sex, older age, prior attempts, psychiatric illness, substance use, access to means, hopelessness) and protective factors. Serotonin syndrome, NMS, and lithium toxicity are emergencies - recognize and manage. Deliberate self-harm vs suicide attempt. Consultation-liaison: psychiatric aspects of medical illness - depression in cancer, delirium, adjustment disorder, capacity assessment, and the interface with medical teams. Understand capacity (understanding, appreciation, reasoning, expressing a choice) and how it differs from competence (a legal determination).
Traps
Capacity is decision-specific and can fluctuate - do not equate psychiatric diagnosis with incapacity. Do not miss medical causes of agitation (hypoglycemia, hypoxia, delirium). Restraint requires monitoring of airway, circulation, and vitals. Distinguish self-harm (often without suicidal intent) from suicide attempt.
Rule of thumb
In any emergency, ABCs and medical causes first, then psychiatric management. For capacity, assess the four elements for the specific decision at hand.