Comparison of Postoperative Pulmonary Complications Between Smokers and Nonsmokers

Cigarette smoking is a well-established risk factor for adverse postoperative outcomes, including respiratory complications. However, many studies have primarily focused on major complications such as pneumonia, reintubation, or prolonged mechanical ventilation, often underestimating early and subtle pulmonary effects of smoking. This study aims to fill that gap by evaluating early minor postoperative pulmonary events-specifically cough, airway secretions, and wheezing-within the first 24 hours after extubation in adult patients undergoing elective abdominal surgery. The study is designed as a prospective observational cohort conducted in a single tertiary-care hospital. Adult patients (aged 18-65) undergoing elective abdominal surgery under general anesthesia will be included. Participants will be classified into two groups based on smoking history: current smokers and non-smokers. The primary outcome is the occurrence of early minor pulmonary complications, including secretion burden requiring aspiration, Peripheral Oxygen Saturation(SpO₂ ) desaturation (SpO₂ \<90%), presence of audible wheezing, and persistent postoperative cough. These events will be documented by trained clinical staff using standardized clinical criteria and data collection forms. The hypothesis of this study is that active smokers are more likely to develop early minor pulmonary complications within the first 24 hours after surgery compared to non-smokers. The findings will contribute to a better understanding of early perioperative respiratory risk among smoking patients and may support the refinement of risk assessment and preoperative counseling.