Evaluation of risk factors for postoperative pulmonary complications after elective open upper abdominal surgery in chronic obstructive pulmonary diseases patients

Abstract

Background: Postoperative pulmonary complications (PPCs) range from 9% to 40% in various nonthoracic surgeries. Various risk factors are attributed for these complications. The aim of this study was to determine the risk factors for PPC in chronic obstructive pulmonary disease (COPD) patients submitted to elective open upper abdominal surgery. Materials and Methods: This was a prospective cohort study conducted in a tertiary care center after obtaining ethical committee clearance. Two hundred and twenty-nine of 427 patients planned for elective abdominal surgeries were labeled as COPD based on spirometry test. PPC and various factors affecting it were analyzed. Pre- and intra-operative data were collected and their association with the occurrence of PPC was analyzed. Relationship between PPC and other variables was tested by linear and logistic regression. Multivariate logistic regression was performed using a backward stepwise approach and accepting statistical significance at P < 0.05. Results: Of 229 COPD patients, 34 (14.84%) suffered PPC. The mean age was 55.76 ± 8.40 years with 78.6% being male. Patients having age >50 years and the American society of anesthesiologists IV status were more prone to developing PPC. The multivariate analysis revealed body mass index (BMI) >30 kg/m2, duration of surgery >150 min, and pCO2>45 mmHg in arterial blood gas as independent predictors of PPC. Conclusions: The present study concluded that increased pCO2, BMI, and longer duration of surgery increase PPC in COPD patients. Hence, preoperative optimization of pCO2, BMI, and a proper plan to shorten the duration surgery may reduce PPC in COPD patients undergoing open upper abdominal surgeries.