Obesity and perioperative noninvasive ventilation in bariatric surgery.

The incidence and prevalence of obesity continues to increase globally. Physicians will therefore provide care for an increasing number of obese patients in their clinical practice. Optimal management of these patients is required to minimize the risk of perioperative complications that increase morbidity and mortality. Obesity affects the respiratory function. It is generally associated with reduced lung volume with increased atelectasis, decreased lung and chest wall compliance, increased airway resistance, and moderate to severe hypoxemia. These physiologic alterations are generally more pronounced in obesity complicated by obstructive sleep apnea syndrome or obesity hypoventilation syndrome. Anesthesia and surgery can profoundly impair respiratory function, increasing the risk of postoperative respiratory complications and acute respiratory failure. Certain comorbidities associated with obesity (e.g., metabolic syndrome, obstructive sleep apnea, pulmonary disease) further increase the risk of perioperative complications. Non-invasive ventilation (NIV) is emerging as an important strategy to minimize perioperative complications. It may ameliorate obesity-related comorbidities, counteract upper airway obstruction, reduce hypoventilation and atelectasis, improve gas exchange and respiratory function, relieve dyspnea, and decrease breathing effort in obese patients in the perioperative period. Thus, NIV may lower the risk of acute respiratory failure after bariatric surgery. Selecting the appropriate interface and type of NIV is fundamental for increasing the likelihood of NIV success in such high-risk patients. NIV is a safe therapy, which should be considered in the perioperative period to help optimize the management of obese patients undergoing bariatric surgery and improve their postoperative course.