Preoperative pulmonary evaluation to prevent postoperative pulmonary complications

Postoperative pulmonary complications (PPCs) arise from a complex interplay of patient, surgical, and anesthesia-related factors. Despite their significant impact, there are currently no standardized guidelines recommending a comprehensive preoperative approach to assessing patients with PPC risk factors. Preoperative pulmonary evaluation (PPE) plays a pivotal role in identifying underlying patient conditions, undiagnosed diseases and optimal treatments. PPE involves systematic identification of patient, surgical, and anesthesia-related risk factors. Severe PPCs include atelectasis, pneumonia, respiratory failure, pulmonary embolism, and worsening chronic lung disease. Surgical urgency, type, duration, approach of the surgical procedure, and comorbidities influence PPC rates, with cardiac, thoracic, abdominal, and vascular surgeries being particularly vulnerable.Patient-related risk factors encompass non-pulmonary and pulmonary factors. Aging populations increase surgical demand, with advanced age and frailty predicting higher morbidity and mortality risks. Conditions like congestive heart failure, obesity, obstructive sleep apnea, and smoking heighten PPC risks. Asthma, chronic obstructive pulmonary disease, interstitial lung diseases, pulmonary hypertension, previous pulmonary thromboembolism, acute respiratory infections, and COVID-19 impact pulmonary risk profiles. Surgery and anesthesia-related risk factors include the site of surgery, operation time, and emergency surgery. Surgery near the diaphragm elevates PPC risk, while longer operation times correlate with increased PPC incidence. Emergency surgeries pose challenges in risk assessment. Anesthetic techniques influence outcomes, with regional anesthesia often preferable. Neuromuscular blocking agents impact PPCs, and protective ventilation strategies can mitigate complications.As current literature lacks a comprehensive approach to PPE, in this review, we present a comprehensive approach to preoperative pulmonary approach to surgical patients to help in risk stratification, further optimization, as well as shared decision making between the surgeon and the patients and their family prior to consenting for a major surgical procedure.