Currently, the following strategies have been explored to improve the lung functions of the patients with morbid obesity during and after laparoscopic abdominal surgeries: (1) Increase tidal volume, (2) Positive end-expiratory pressure (PEEP), and (3) Vital capacity maneuver (VCM) ( 21, 22). All these pulmonary complications are further complicated in patients with morbid obesity, hence, anesthetic care for these patients during and after laparoscopic surgery is more challenging, not only to the anesthesiologists but also to the surgeons and pulmonologists. Consequently, postoperative pulmonary complications, such as atelectasis and mismatching of the ventilation/perfusion ratio, may occur in the patients undergoing laparoscopic abdominal surgery ( 17– 20). However, the pneumoperitoneum and steep Trendelenburg position can cause a decrease in respiratory compliance, increase of intrathoracic pressure, and the reduction of functional residual volume ( 14– 16). It has been reported that a minimally invasive laparoscopic surgery in patients with morbid obesity and with endometrial cancer was associated with fewer complications and fewer days of hospital stay compared to open surgery ( 11– 13). Laparoscopic sleeve gastrectomy benefits patients with obesity by providing a quicker post-surgery recovery and shorter hospital stays ( 7– 10). These alterations include a reduced functional residual capacity (FRC), reduced lung and chest wall compliance, increased lung resistance, reduced oxygenation, and increased work of breathing ( 5, 6). In this regard, compared to a normal healthy person, significant alteration of respiratory mechanics exists in obesity, which is further augmented with general anesthesia or with underlying lung diseases. This is due to patients with obesity having altered respiratory mechanics and metabolic syndrome/s ( 3, 4). Pulmonologists are also confronted with properly ventilating these patients, along with maintaining normal lung function when they emerge from general anesthesia.

As a result of the current obesity epidemic, anesthetists are not the only ones challenged with anesthetizing patients with obesity. In the European Union (EU) countries, approximately 40–50% of men and 25–35% of women were overweight and 15–25% of men and women were obese in 2008 ( 2). It has been reported by the National Health and Nutritional Examination Survey (NHANES) that the prevalence of obesity in the USA was 40.4% for women and 35% for men in 2016 ( 1). The prevalence of obesity is increasing worldwide. The PaO 2 and oxygen index (OI) before and after intubation with mechanical ventilation were significantly higher at 30°-RTP compared to that at supine position, and in contrast, the P A−aO 2 before and after intubation with mechanical ventilation was significantly reduced at 30°-RTP compared to that at supine position.Ĭonclusion: During and after laparoscopic sleeve gastrectomy, patients with morbid obesity had improved lung function, reduced pulmonary shunt, reduced P A−aO 2 difference, and increased PaO 2 and oxygen index at 30°-RTP compared to that supine position. Patients' static lung compliance (Cstat), during mechanical ventilation, was significantly improved at 30°-RTP (36.8 ± 6.7) compared to that of those in a supine position (33.8 ± 7.3, p < 0.05). Pulmonary shunt (Qs/Qt) after extubation was significantly lower at 30°-RTP (18.82 ± 3.60%) compared to that at supine position (17.13 ± 3.10%, p < 0.01). Results: A total of 15 patients with morbid obesity were enrolled in this self-compared study. Before intubation, after intubation with mechanical ventilation, and after extubation, arterial blood was collected for blood oxygenation and gas analysis after posturing the patients at supine position or 30° reverse Trendelenburg position (30°-RTP). Methods: Patients with morbid obesity (BMI ≥ 30 kg/m 2, ASA I – II grade) who underwent laparoscopic sleeve gastrectomy at our hospital from June 2018 to January 2019 were enrolled in this prospective study.

3Education Centre, China Medical Tribun, Beijing, Chinaīackground: This study aimed to evaluate the impact of patients' positioning before and after intubation with mechanical ventilation, and after extubation on the lung function and blood oxygenation of patients with morbid obesity, who had a laparoscopic sleeve gastrectomy.2Department of Anesthesiology, The First Affiliated Hospital of Xiamen University, Xiamen, China.1Department of Anesthesiology, China-Japan Union Hospital of Jilin University, Changchun, China.

Dengyu Gao 1 †, Lu Sun 2 †, Ning Wang 1, Yubo Shi 1, Jianli Song 1, Xiaoying Liu 1, Qiyao Yang 3 and Zhenbo Su 1 *