Factors Affecting a Change in Pulmonary Function Following Laparoscopic Sleeve Gastrectomy: A 1-Year Observational Study

Background: Obesity may lead to impaired pulmonary function because of both the condition itself and its associated comorbidities. The change in pulmonary function following laparoscopic sleeve gastrectomy (LSG) and the factors affecting it were evaluated in our study. Methods: A retrospective study was carried out on 61 patients undergoing LSG between January 2014 and January 2015 for morbid obesity (body mass index [BMI] ≥40 kg/m2), who were at least 12 months post-op. Our analysis considered pre- and 12-month postoperative demographic data; the presence of comorbidities; smoking habit; American Society of Anesthesiologists (ASA) scores; weight; BMI values and spirometry results. Results: The study comprised 61 cases: 8 men (13%) and 53 women (87%), with a mean age of 36.08 ± 8.47 years. Preoperative and 12-month postoperative values for weight and BMI differed significantly (both p < 0.001). The spirometry results 12 months postoperatively revealed a significant reduction in forced expiratory volume in the first second (FEV1): p < 0.001; an increase in FEV1%: p < 0.001 and reductions in FEV1/forced vital capacity (FVC) and FEV1/FVC% values: p < 0.001 compared with preoperative values. Smoking, ASA scores and the presence of comorbidities were also seen to affect pulmonary function; whereas obesity onset age (childhood or adulthood) showed no impact. Conclusions: In morbidly obese patients, weight loss following LSG, the presence of comorbidity, smoking and the ASA score may affect pulmonary function.