Perioperative risk assessment - focus on functional capacity.

Area of Science:

• Preoperative Medicine
• Risk Stratification
• Functional Capacity Assessment

Background:

• Functional capacity, or cardiopulmonary fitness, is linked to muscular strength, balance, and frailty.
• Poor functional capacity correlates with increased postoperative morbidity, particularly noncardiovascular complications.

Purpose of the Study:

• To review how functional capacity aids in preoperative risk stratification.
• To evaluate the strengths and limitations of methods for estimating functional capacity.

Main Methods:

• Review of existing literature on functional capacity assessment methods.
• Analysis of patient interviews (structured vs. unstructured) and various exercise tests.

Main Results:

• Unstructured patient interviews are poor predictors of outcomes.
• Structured interviews using validated questionnaires (e.g., Duke Activity Status Index) or standardized physical activity questions predict moderate-to-severe and cardiovascular complications.
• Cardiopulmonary exercise testing (CPET) shows the most consistent association with complication risks.
• Simpler exercise tests like the 6-min walk test require further evaluation.

Conclusions:

• Structured interviews with validated questionnaires or standardized physical activity questions offer a straightforward approach to assessing functional capacity.
• Exercise tests, particularly CPET, are supported by strong evidence for functional capacity assessment.
• Further research is needed to define the role of simpler exercise tests in preoperative evaluation.