20.1 Mental Status Assessment, Cognition & Capacity to Consent

20.1 Mental Status Assessment, Cognition & Capacity to Consent

CPCF Appendix A minimum entry-to-practice skill #17 — Determine mental health status — has three components: assess the patient's capacity to consent to care decisions, consider risk and cognitive factors, and recognize substance use, addictions, mental health and psychiatric conditions in patients. Foundational knowledge #3 adds cognition: arousal, attention, orientation, emotion, processing, registration of information, retention and recall, communication and language proficiency, and perception and decision-making as it relates to autonomy, disclosure, and consent.

This is one of the most under-studied areas on the COPR examination and one of the most heavily weighted in practice.

Rule Out the Organic Cause First

The single most examined principle: a psychiatric presentation is a diagnosis of exclusion in the field. New or changed behaviour is a medical emergency until the treatable causes are excluded.

Work through AEIOU-TIPS:

[!CAUTION] Check the blood glucose in every patient with altered behaviour, every time. Hypoglycaemia mimics intoxication, aggression, psychosis, and stroke, and it is free to exclude. Attributing altered mentation to intoxication or mental illness without a glucose reading is the error that appears most often in coroners' findings and in examination distractors.

Delirium Versus Dementia Versus Psychiatric Illness

Delirium is a medical emergency with a mortality comparable to sepsis or myocardial infarction. Two features separate it from almost everything else: acute onset with a fluctuating course, and inattention. A patient who cannot keep track of your question halfway through it has inattention.

Visual hallucinations point toward an organic cause — delirium, withdrawal, intoxication, or occipital pathology. Purely auditory hallucinations are more typical of a primary psychotic illness. A patient with a known schizophrenia diagnosis who develops visual hallucinations has a new problem, not a relapse.

The Prehospital Mental Status Assessment

A structured assessment you can perform and document:

Asking About Suicide

Asking about suicide does not plant the idea — this is one of the most robustly established findings in the field, and the opposite belief is a distractor. Patients are overwhelmingly relieved to be asked plainly.

Ask progressively and without euphemism:

1. "Things sound really hard right now. Have you had thoughts of ending your life?"
2. If yes: "Have you thought about how?" — a specific plan raises risk substantially.
3. "Do you have access to what you'd need?" — available means, particularly firearms or stockpiled medication, raise risk substantially.
4. "Have you done anything to prepare?" — giving away possessions, writing notes, settling affairs.
5. "What has stopped you so far?" — protective factors, and often the most therapeutic question you will ask.

Risk factors include previous attempts (the strongest single predictor), a recent attempt, a psychiatric diagnosis, substance use, chronic pain or terminal illness, recent loss, social isolation, and access to lethal means. A sudden calm after a period of severe distress may signal that a decision has been made and is a warning sign, not an improvement.

Document the risk assessment factually and hand it over explicitly. Never promise confidentiality you cannot keep; instead be honest: "I'm going to share this with the team who can help you."

Capacity to Consent

Indicator A3.3 requires paramedics to obtain and maintain informed consent appropriately for the practice context. Capacity is the clinical assessment that makes consent meaningful.

Four Principles

1. Capacity is presumed. Every adult is presumed capable until there is evidence otherwise. A psychiatric diagnosis, an intellectual disability, a dementia diagnosis, intoxication, or a decision you disagree with does not by itself remove capacity.
2. Capacity is decision-specific. A patient may have capacity to consent to a dressing but not to refuse transport for a subarachnoid haemorrhage. Assess capacity for the decision in front of you.
3. Capacity is time-specific. It fluctuates with pain, hypoxia, hypoglycaemia, intoxication, and delirium. A patient who lacks capacity now may regain it in twenty minutes, and correcting the reversible cause is part of the assessment.
4. An unwise decision is not incapacity. The test is the process of decision-making, not the outcome.

The Four-Part Test

A patient has capacity for a decision if they can:

1. Understand the information relevant to the decision;
2. Retain it long enough to use it;
3. Use or weigh it in reaching a decision; and
4. Communicate the decision by any means.

All four must be present. The most commonly failed element in practice is use or weigh — a patient who can repeat everything you said but cannot connect it to themselves ("yes, a bleed in the brain can kill you, but that won't happen to me") is not weighing the information.

When Capacity Is Absent

• Provide care in the patient's best interests, limited to what is necessary and proportionate.
• Establish whether a substitute decision-maker, power of attorney for personal care, or advance directive exists — mechanisms and hierarchies are set by provincial legislation and differ between provinces.
• Involve family and the circle of care with appropriate consent (indicator B2.3).
• Document the capacity assessment itself: what you told the patient, what they said back, and which element of the four-part test failed.

Involuntary Apprehension

Every province has mental health legislation permitting apprehension and involuntary examination of a person who, because of an apparent mental disorder, poses a risk of harm to themselves or others. The specific criteria, the forms, and who holds the authority — police, a physician, and in some provinces designated health professionals — vary by province. Entry-level expectations:

• Know the framework in your own jurisdiction and who may authorize apprehension there.
• Paramedics generally do not hold apprehension authority under mental health legislation in most Canadian jurisdictions; they work alongside police and physicians who do.
• The common-law duty to act in an emergency still permits necessary care for a patient who lacks capacity and faces serious harm.
• Restraint requires its own justification and is covered in Section 20.2.
• Document the legal basis for every action taken without consent.

Communication That Works

• Approach calmly, from the front, at eye level where safe, with a comfortable distance and an unobstructed exit for both of you.
• One clinician talks. Multiple voices increase arousal.
• Use short sentences and allow long pauses. Processing is slowed in distress, intoxication, and delirium.
• Do not argue with a delusion or a hallucination. You cannot reason someone out of a fixed belief, and trying costs you the relationship. Acknowledge the feeling instead: "That sounds terrifying. You're safe with me."
• Offer choices where real ones exist — which arm, sitting or lying, who comes along. Autonomy preserved in small things buys cooperation in large ones.
• Name what you are doing before you do it. Surprise is the enemy.