Anaesthesia for bariatric surgery

Abstract

The word ‘bariatric’ is derived from the Greek words baros meaning ‘weight’ and iatrics meaning ‘medical treatment’. Obesity is one of the greatest health challenges facing Western countries. Obesity is defined as a body mass index (BMI) .30 kg m, whereas those with a BMI .35 and .55 kg m are considered ‘morbidly’ obese and ‘super morbidly’ obese, respectively. Recent figures suggest that up to 23% of men and 25% of women in the UK are obese. Associated obesity-related medical conditions include hypertension, coronary artery disease, sudden (cardiac) death, restrictive lung disease, obstructive sleep apnoea (OSA), diabetes mellitus, gallstones, a range of cancers (breast, gynaecological, and gastrointestinal), degenerative joint disease, and socioeconomic and psychosocial impairment. Quality of life and life expectancy are reduced. Obesity also leads to an increased demand for health-care services. Studies have shown that weight loss of 5– 10% of initial body weight can improve glucose intolerance, type II diabetes mellitus, hypertension, and hyperlipidaemias. Treatment for overweight patients should encompass a multidisciplinary team offering a complete weight loss programme, which includes diet and lifestyle modification alongside increased physical activity. Approved drug therapy may also have a role in weight loss. Unfortunately, weight loss obtained by these non-invasive measures is rarely sustained, which has led to bariatric surgery increasingly being offered as a solution. Bariatric surgery has been recommended by the National Institute of Clinical Excellence as a treatment for obesity. Bariatric procedures may achieve weight loss of more than 50% of excess weight. Bariatric surgery is relatively safe, has low morbidity and mortality, and can provide longterm sustained weight loss with significant improvement of co-morbidity and quality of life in the morbidly obese patient. It is one of the fastest growing areas of surgery in terms of patient numbers treated. This reflects both the ability of bariatric surgical procedures to provide a solution to an otherwise insoluble problem and the evolution of safer, less invasive surgical methods. This article will focus on anaesthesia and how it relates directly to the speciality of bariatric surgery. For a more detailed and generalized review of obesity and how it relates to anaesthesia, the reader is directed to alternative text for further reading.