Respiratory management of the obese patient undergoing surgery

Obesity, as defined by a body mass index (BMI) of ≥30 kg/m2 (1), has almost doubled since 1980 to affect an estimated 671 million individuals worldwide (2). Furthermore, morbid obesity, defined as a BMI above 40 kg/m2, is rising (3). In the United States, China and United Kingdom (UK), obesity has a current prevalence of 32%, 4% and 25%, respectively in adult males and 34%, 5% and 25% respectively in adult females (2). The direct cost to the NHS in England for treating obesity, and its related morbidity, is estimated to be above ￡4 billion (4). The UK reported a 30-fold increase in the number of bariatric surgical procedures over ten years, a ten-fold increase in the number of hospital episodes primarily related to obesity over a decade (5) and it has been estimated that 25% of all UK patients admitted to intensive care units (ICU) are obese with 7% morbidly obese (6). It is therefore not surprising that the respiratory management of obese subjects, in particular in the pre- and peri-operative stage, represents a growing challenge to surgeons, pulmonologists, anesthetists and intensivists (7,8). This review will detail the physiological effects of obesity on the respiratory system and report the evidence-based strategies to manage the pre- and peri-operative phase