MULTIVARIATE-ANALYSIS OF FACTORS ASSOCIATED WITH POSTOPERATIVE PULMONARY COMPLICATIONS FOLLOWING GENERAL ELECTIVE SURGERY

Objective: To develop a predictive model identifying perioperative con ditions associated with postoperative pulmonary complications (PPCs). Design: A prospective survey of patients whose preoperative history an d physical examination, spirometric, PaO2 and PaCO2 analysis, and oper ative results were recorded. These patients underwent postoperative ca rdiopulmonary examinations until they were discharged from the hospita l; their medical records were also reviewed until they were discharged from the hospital. Setting: The Louisville Veterans Administration Me dical Center, Louisville, Ky. Patients: A randomly chosen sample of pa tients aged 40 years or older who required elective, nonthoracic surge ry under general or spinal anesthesia and who were hospitalized at lea st 24 hours postoperatively. Main Outcome Measure: An analysis of risk factors associated with the development of 1 or more of the following conditions: acute bronchitis, bronchospasm, atelectasis, pneumonia, a dult respiratory distress syndrome, pleural effusion, pneumothorax, pr olonged mechanical ventilation, or death secondary to acute respirator y failure. Results: Postoperative pulmonary complications developed in 16 (11%) of 148 patients. The risk factors found to be higher among t hose with PPCs compared with those without PPCs were postoperative nas ogastric intubation (81% vs 16%, P < .001), preoperative sputum produc tion (56% vs 21%, P = .005), and longer anesthesia duration (480 vs 30 9 minutes, P < .001). Upper abdominal surgery was performed in 11 (69% ) of the 16 patients with PPCs and in 20 (15%) of the 132 patients wit hout PPCs (P < .001); this difference lost significance in multivariat e analysis. The final linear logistic model included postoperative nas ogastric intubation (odds ratio [OR], 21.8), preoperafive sputum produ ction (OR, 4.6), and longer anesthesia duration (OR exp[0.01x] for an increase in x minutes) (1 minute of additional anesthesia time increas es the OR to 1.01), resulting in 92%, accuracy in predicting PPCs. Con clusions: We identified 3 potentially modifiable risk factors for PPCs , If validated, our results may lead to modifications of perioperative care that will further reduce PPCs.