A psychiatry opinion that an adult patient with delirium lacks capacity to refuse an amputation answers one question; it does not, by itself, authorize the operation. The next task is to establish whether the decision can wait for recovery, then identify the lawful and proportionate route if delay risks serious harm. This article uses the Mental Capacity Act framework in England and Wales as a worked example; laws and proxy roles differ elsewhere.
Keep the capacity opinion narrow
Capacity concerns this decision, at this time. Under the England and Wales framework, the assessment asks whether an impairment or disturbance of the mind or brain leaves the person unable to understand, retain, use or weigh relevant information, or communicate a decision. A person need not fail every part of the test; equally, delirium or confusion alone does not prove incapacity. Retaining information briefly can be enough if the person can use it to decide.
Support the person before concluding they cannot decide: explain the operation and alternatives in simple terms, address pain or sensory barriers, use an interpreter if needed, and choose the clearest time of day. If the patient’s condition allows, treat reversible contributors to delirium and reassess. A patient who lacks capacity for surgery may still decide other matters, and may regain capacity as the confusional state improves.
Psychiatry can clarify the mental state, baseline, likely fluctuation, communication needs, and how delirium affects the specific decision. The team responsible for the operation must still establish its clinical indication and ensure that treatment has a valid legal basis.
Incapacity is not the same as permission
The next question is not simply, ‘What do the doctors think is best?’ The decision-maker must be identified. If a registered health-and-welfare attorney or court-appointed deputy has authority for this treatment, that person makes the decision within the scope of their authority. Otherwise, the clinician responsible for the proposed treatment ordinarily makes the best-interests decision. Psychiatry’s capacity opinion informs that process; it does not itself authorize surgery.
Best-interests reasoning must center the person’s own perspective: their current and past wishes, values and beliefs, the likely benefits and burdens of surgery, realistic alternatives, and the consequences of doing nothing. Preserving life may be a major consideration, but it is not the only one.
A family member can provide vital evidence about what the patient would have wanted, but is not automatically authorized to consent or refuse on an adult’s behalf. Check for a valid, applicable advance decision refusing the proposed treatment, and for a registered health-and-welfare lasting power of attorney or court-appointed deputy with relevant authority. Verify the scope of any appointment: an attorney can decide about life-sustaining treatment only if the LPA expressly grants that authority; a deputy’s powers are set by the court order, and a deputy cannot refuse life-sustaining treatment.
| What you find | What to do next | Avoid assuming |
|---|---|---|
| No known advance refusal or authorized proxy | The clinician responsible for the proposed treatment ordinarily makes the best-interests decision, using clinical facts, the person’s wishes and values, and appropriate consultation | That incapacity alone settles the treatment choice |
| A possible advance refusal or legal proxy | Check validity, applicability, and the exact scope of authority; escalate uncertainty promptly | That a relative’s account is the same as a binding refusal or consent |
| No appropriate person to consult about qualifying serious treatment | Check whether the statutory Independent Mental Capacity Advocate process applies | That the advocacy process must delay treatment when the statutory urgency exception applies |
In England and Wales, where an NHS body proposes qualifying serious medical treatment and there is no appropriate non-professional person to consult, the Mental Capacity Act requires an Independent Mental Capacity Advocate to be instructed. If treatment needs to be provided urgently, it may proceed without prior instruction of an advocate. That exception concerns the timing of advocacy; it does not replace the best-interests decision or provide some other missing treatment authority. Check the applicable criteria and local process rather than treating every operation—or every emergency—the same way.
Let urgency shape the timing, not erase the safeguards
Ask the surgeons to explain the clinical time window: what harm is expected if the operation is delayed, how soon it may occur, and whether a less invasive or temporary option could safely bridge the gap. ‘Urgent’ should describe the risk of waiting, not serve as a shortcut around assessment.
If the patient lacks capacity, no valid applicable refusal or authorized proxy decision prevents the proposed treatment, the patient’s relevant wishes cannot be established in time, and treatment is immediately necessary to save life or prevent serious deterioration, emergency guidance may support proceeding under the applicable legal framework. The operation still needs a defensible rationale, and the least restrictive option should be chosen where there is a choice.
An emergency alone does not cancel a valid, applicable advance refusal or a decision made by an authorized attorney or deputy. The Mental Capacity Act has a narrow interim provision: while a relevant issue is being referred to the Court of Protection, life-sustaining treatment or an act reasonably believed necessary to prevent serious deterioration may be provided. This is not a general emergency override; seek urgent legal advice and pursue the court decision when this provision is relevant.
If delay is safe, use that time to improve the patient’s ability to decide, seek collateral and verify legal documents. If there is a serious dispute about the patient’s wishes, the proxy’s authority, or the balance of benefits and burdens, seek senior, ethics and legal advice, including advice about court involvement. Do not assume that urgency itself resolves a dispute.
Treat resistance as a separate decision
A best-interests decision about surgery does not automatically settle whether, or how, treatment may be delivered over active resistance. Under the Mental Capacity Act, restraint can fall within the section 5 protection only when there is a reasonable belief that it is necessary to prevent harm to the person and it is proportionate to the likelihood and seriousness of that harm. The Act’s least-restrictive principle also matters. Its ordinary care-and-treatment powers do not permit an act that conflicts with a decision made by an attorney or deputy acting within their authority; follow the legal escalation route above if such a conflict arises.
Plan any proposed restraint or sedation with the surgical, anaesthetic and relevant clinical teams. Use the least restrictive effective approach, minimize fear and distress, and review it as circumstances change. Restraint is not punishment, and a blanket claim that ‘life-saving surgery permits any force’ is not a safe legal or clinical conclusion. For substantial force or unresolved legal uncertainty, obtain urgent institutional legal advice.
Make the record show the reasoning
Document the specific operation and decision assessed; the relevant capacity findings and their connection to delirium; the support offered; and why waiting for reassessment is or is not safe. Record the clinical options and likely consequences, evidence of prior wishes or values, the people consulted, any advance decision or proxy authority checked, who made the decision and under what authority, and why the chosen plan is proportionate. If restraint is proposed, record its purpose, necessity, proportionality, alternatives considered, and review plan.
Practical takeaways
- A capacity finding about surgery is not, by itself, consent or authority to operate.
- If time allows, support decision-making, address delirium contributors, and reassess.
- Treat relatives as sources of information unless they hold verified legal authority.
- Weigh the person’s wishes and values alongside clinical benefit, burdens, alternatives, and the consequences of no surgery.
- Keep emergency treatment and restraint decisions specific, proportionate, and documented; urgency does not by itself override an applicable refusal or authorized proxy decision.
- Check the law where care is being delivered.
