Perioperative Assessment, Monitoring, and Coexisting Disease
Risk stratification
Perioperative assessment answers three questions: what is the patient's baseline reserve, what is the surgical stress, and what can be modified before incision? ASA physical status summarizes overall disease burden but does not predict a specific outcome. Functional capacity is practical: patients who can climb a flight of stairs or walk briskly (≥4 METs) generally tolerate major noncardiac surgery without further cardiac testing; those below 4 METs with risk factors need individualized evaluation.
The Revised Cardiac Risk Index (RCRI) uses six predictors: high-risk surgery, history of ischemic heart disease, heart failure, cerebrovascular disease, insulin-treated diabetes, and creatinine >2 mg/dL. It estimates perioperative major adverse cardiac events but is not a universal screening tool.
Coexisting disease management: continue beta-blockers, avoid routine bridging of anticoagulants, stop direct oral anticoagulants according to drug, renal function, and bleeding risk, and optimize asthma or COPD before elective surgery. Obstructive sleep apnea requires postoperative monitoring and opioid-sparing plans.
Traps
Treating a single abnormal test as an automatic cancellation; using RCRI in isolation; assuming all anticoagulants need bridging; missing frailty and cognitive impairment.
Worked example
A patient with insulin-treated diabetes and stable angina undergoing open colectomy has two RCRI predictors (high-risk surgery, insulin-treated diabetes). That is an intermediate-risk combination; document risk, optimize medical therapy, and arrange appropriate postoperative monitoring rather than ordering routine stress testing.