01Principles and purposeThe professional or clinical skill and the decisions it supports.
Risk stratification is useful when it changes care. It can identify a need for anaesthetic review, preoperative optimisation, specialist postoperative monitoring or a more detailed discussion about whether an operation serves the patient’s goals. A numerical estimate alone does none of these things. The central task is to combine the likely benefit of treating the surgical condition with the burdens of the intervention and recovery, including what may happen if surgery is delayed or not performed.
Frailty describes vulnerability to adverse outcomes after a stressor and is related to reduced physiological reserve. It is not synonymous with chronological age, one chronic diagnosis or living with a disability. Two people of the same age can have very different recovery needs, and someone who appears dependent during an acute admission may have been independent before becoming ill. Surgical assessment should therefore establish baseline function and the source of that information, then identify modifiable problems and the support needed across the entire pathway.
Key points
- Risk depends on the person, the procedure and its urgency; age alone is not a sufficient decision rule.
- Use a validated surgical risk tool to supplement clinical assessment and explain its endpoint, population and uncertainty.
- Assess frailty from usual function and a validated approach, with collateral information where needed; acute illness can distort the bedside impression.
- Distinguish frailty, disability, comorbidity, cognition and capacity rather than treating them as interchangeable labels.
- Compare surgery with realistic alternatives and non-operative care using outcomes that matter to the individual.
- Link identified risks to optimisation, senior involvement, postoperative support and a documented review of the shared plan.
02Situations and prioritiesThe context, relevant information and actions that matter most.
Assess patient factors such as organ dysfunction and reserve, procedure factors such as expected physiological stress and blood loss, and urgency that limits preparation. A modest operation may still be difficult for someone with severe unstable disease; a large operation may be tolerated differently by otherwise similar patients with different function. Explain these interactions instead of attributing the whole risk to age.
Ask what the person ordinarily does at home, how far they walk, what stops them, and what help is needed with everyday tasks. Establish whether limitations arise from breathlessness, pain, neurological impairment, fatigue or social circumstances. The reason matters: poor mobility caused by a local joint problem should not automatically be interpreted as the same cardiopulmonary limitation as exertional breathlessness.
Use an appropriate validated frailty assessment, informed by usual function and collateral history where necessary. CPOC and BGS recommend documenting frailty in older surgical patients and younger people at risk, and comprehensive geriatric assessment for people living with frailty identified at CFS 5 or above. The assessment should lead to action on associated cognitive, nutritional, functional and medicine-related problems.
Identify pre-existing cognitive difficulty and possible acute delirium, but do not infer inability to make a decision from age, frailty or a diagnosis alone. Support communication and assess decision-making ability for the specific choice when needed. A family member can provide invaluable baseline information without automatically taking over a decision that the patient can make.
Ask which outcomes the person values: symptom relief, time at home, independence, survival, avoiding repeated admissions or maintaining a particular role. A treatment can improve one outcome while risking another. Identifying that trade-off early allows clinicians to discuss realistic recovery trajectories rather than focusing solely on whether the patient will survive the operation.
03Assessment and interpretationHow to gather information, assess the situation and recognise uncertainty.
Consider the information, its meaning and its limitations before deciding what follows.
- 01
Validated perioperative risk assessment - Why
- Provide a structured estimate that supplements clinical judgement and supports planning.
- Interpretation and limitations
- Choose a tool validated for the procedure and setting, enter accurate current inputs and identify the outcome and time horizon it predicts. A mortality model does not directly predict loss of independence or quality of life. Do not extrapolate a model beyond its intended population or imply that an estimate is a personalised certainty.
- 02
Frailty assessment and collateral history - Why
- Identify vulnerability and the need for broader perioperative assessment.
- Interpretation and limitations
- Document the tool, relevant baseline information and who provided it. Avoid grading solely from how the patient performs during an acute illness. When disability or another condition complicates interpretation, seek experienced assessment and use the tool’s intended scope rather than forcing an unsupported numerical label.
- 03
Targeted medical and functional assessment - Why
- Identify reversible disease or specific risk that could alter the operative plan.
- Interpretation and limitations
- Use symptoms, examination and the proposed procedure to select tests such as ECG, renal studies or further cardiopulmonary evaluation. Routine indiscriminate testing can delay care without answering a relevant question. New unstable symptoms need assessment in their own right, not merely entry into a calculator.
- 04
Nutrition, cognition and recovery resources - Why
- Find factors that affect recovery and can be addressed before and after surgery.
- Interpretation and limitations
- Screen nutritional risk and assess cognition, medicines, mobility, support at home and likely rehabilitation needs. Laboratory values alone do not describe nutritional status. Relate each finding to a practical action and responsible professional so a multidisciplinary assessment becomes a deliverable care plan.
04Worked approachesCases with ordered reasoning, an action and a check of the outcome.
01Worked case: a risk discussion with competing goalsPlan around the person’s prioritiesAn 81-year-old is considering elective major abdominal surgery. They live alone with help for shopping, have recently lost weight and say that remaining at home matters more to them than a small gain in life expectancy. The operation may relieve symptoms but could involve prolonged recovery.+
- 1Establish baseline function, nutritional history, comorbidities and the meaning of the help they receive. Use an appropriate frailty assessment and a validated operative-risk tool, with senior interpretation of the procedure and expected recovery.
- 2Ask the person to explain their concerns and desired outcome. Discuss expected benefit, major complications, possible increased care needs and alternatives, including what non-operative care would involve and the risks of leaving the condition untreated.
- 3Arrange targeted optimisation and multidisciplinary input for the identified problems. If frailty assessment supports it, involve comprehensive geriatric assessment rather than treating a score as a yes-or-no permission for surgery.
- 4The decision is a shared, documented plan that may be to proceed with added support, reconsider timing, choose another treatment or decline surgery. The scenario does not provide enough information to choose one outcome on the patient’s behalf.
- 5Verify understanding by asking the patient to describe the options and likely recovery in their own words. Record their priorities, remaining questions, review arrangements and who will coordinate optimisation and the final decision.
02Risk-informed preparationConvert a risk factor into actionAssessment identifies a modifiable problem before an operation whose urgency permits some preparation.+
- 1Define the problem and the plausible benefit of addressing it, such as investigation of anaemia, improved nutrition or management of unstable cardiopulmonary symptoms. Avoid promising that optimisation eliminates risk.
- 2Agree what can realistically be achieved within the available time, with the surgical and anaesthetic teams weighing the consequences of delay. In urgent disease, optimisation and operative preparation may need to proceed together.
- 3Allocate treatment, review and communication responsibilities, and revisit the risk discussion when new information changes the balance. Specify the postoperative setting and support rather than assuming a routine ward will meet every need.
03Emergency risk conversationCommunicate when time is limitedA person with substantial comorbidity requires an urgent decision about an abdominal emergency and cannot undergo prolonged prehabilitation.+
- 1Assess reversible physiological threats and obtain the necessary senior surgical, anaesthetic and critical-care input. Gather essential baseline function and preferences alongside treatment rather than delaying urgent care for a lengthy assessment tool.
- 2Explain the immediate condition, expected benefit and burdens of surgery, realistic alternatives and uncertainty in concise language. Support the patient’s participation and address decision-making difficulties appropriately.
- 3Document the agreed plan, including postoperative support and treatment-escalation discussions where relevant. Revisit decisions if the condition, prognosis or expressed preferences change.
05Feedback, follow-up and evidenceReview outcomes, seek feedback and identify what to improve.
- After optimisation, assess whether the intended problem improved and whether that changes the operative plan; completion of appointments is not the same as an improved clinical state.
- Update risk information when new illness, deterioration or a change in the proposed procedure makes earlier estimates less applicable.
- Monitor recovery against the person’s baseline function and agreed goals, including cognition, mobility and ability to manage at home, alongside ordinary complication surveillance.
- At discharge and subsequent review, communicate ongoing rehabilitation and support needs and identify who will address a recovery trajectory that differs from expectations.
06Special situationsVariants, exceptions and circumstances that change the usual approach.
Absolute risk needs a denominator
When giving numerical risk, identify how many people out of the same-sized group experience the outcome over the same period. Explain both occurrence and non-occurrence without switching denominators. A relative increase alone can sound dramatic while leaving the patient unable to judge the size of the risk.
Prediction differs from preference
A model estimates an outcome under defined conditions; it does not determine whether that outcome is acceptable to the person. Two patients with similar estimated risk may make different reasonable choices because they value independence, symptom relief or longevity differently.
Frailty is an invitation to plan
Identifying vulnerability should prompt better coordination and proportionate support, not automatic exclusion. Equally, it should not be dismissed as inevitable ageing. Describe the associated needs and how the perioperative pathway will address them, including rehabilitation and communication.
Avoid false precision
A risk estimate may look exact because a calculator prints a decimal. Input uncertainty, model limitations and differences from the development population still matter. Communicate the estimate as one source of evidence within a clinical discussion and state important outcomes that the tool does not predict.
07Common pitfallsFrequent interpretation and management errors.
- 01
Using an age threshold alone to decide access to surgery ignores individual reserve, benefit and preferences.
- 02
Assigning frailty entirely from temporary dependence during an acute illness can overstate the person’s usual vulnerability.
- 03
Equating a mortality estimate with the chance of returning home independently misuses the model’s endpoint.
- 04
Listing risks without discussing alternatives, expected benefit and the patient’s priorities produces an incomplete shared decision.