Focus on: BariatricAnaesthetic considerations and management of the obese patient presenting for bariatric surgery
Introduction
Historically, obesity has been associated with affluence and fertility. With rates of both adult and childhood obesity rapidly rising, obesity no longer signifies affluence but is instead becoming one of the leading public health issues facing the developed world. Between 1993 and 2004, the prevalence of adults in England with a Body Mass Index (BMI) of 30 kg/m2 or greater increased from 13.6% to 24.0% in men and from 16.9% to 24.4% in women. If recent trends in adult obesity continue, it has been projected that approximately a third of all adults (almost 13 million individuals) will be obese by 2012.1 Obesity has long been recognized as a precursor of morbidity and premature mortality. Epidemiological studies show morbidity and mortality to be positively correlated with a BMI > 30 kg/m2, and individuals with a BMI > 35 kg/m2 at aged 50 years have double the risk of premature death.
The field of bariatric surgery in the UK has undergone exponential growth within the last decade. Bariatric surgery is associated with improved rates of sustained weight loss, long-term reduction in obesity-related disease and a decline in long-term mortality.2
The obese patient presents particular challenges for the anaesthetist. We can expect to be increasingly confronted with this patient population, as the demand for bariatric intervention escalates. This article reviews the anaesthetic assessment and management of the morbidly obese patient presenting for bariatric surgery. The surgical management of obesity is discussed elsewhere in this issue by Khwaja and Bonanomi.3
Section snippets
Background
The World Health Organization (WHO) classifies obesity based on BMI, and describes;
Class I obesity – BMI of 30–34.99,
Class II obesity – BMI of 35–39.99,
Class III obesity – BMI equal to or greater than 40.
Individuals with a BMI of 35 or greater who have concomitant, obesity-associated disease or those with a BMI of 40 or greater, regardless of co-morbidities, are described as morbidly obese. Although BMI is the most commonly used tool for assessing the severity of obesity, it is not necessarily
Pre-operative assessment
The objective of pre-operative assessment is to optimize patient outcomes. It facilitates the appropriate selection of patients suitable for bariatric surgery, enables timely identification and treatment of pre-existing medical conditions, and determines how and where each patient should be managed post operatively. The bariatric multi-disciplinary team (MDT) approach to pre-operative assessment ensures that patients are appropriately selected, informed and motivated, and optimized medically.
Intra-operative management
Bariatric patients should be managed at a facility that is appropriately equipped and staffed. This includes specialised interventional, diagnostic, transport and operating room equipment, and access to critical care facilities. In 2007, the AAGBI recommended that each hospital should have a designated consultant anaesthetist and theatre staff member who are responsible for ensuring that the operating suite is adequately resourced to safely manage the morbidly obese patient.17
Routine monitoring
Post-operative management
Bariatric patients are at increased risk of both early and late post-operative complications. Initial post-operative considerations include airway and respiratory support, pain control and prevention of thromboembolism.
Extubation in morbid obesity carries serious risk of loss of airway control, rapid onset of hypoxaemia, haemodynamic instability and pulmonary aspiration. At the end of the procedure, patients should be extubated by experienced anaesthetists in the semi-upright or sitting
Conclusion
The number of patients resorting to bariatric surgery for sustained weight loss is increasing exponentially. These patients are at increased risk of peri-operative complications by the presence of obesity related co-morbidities, and not their BMI per se. Preoperative identification and optimization of associated disease in conjunction with perioperative management by a multidisciplinary team is essential to optimize patient outcome and reduce healthcare costs.
Conflict of interest
Neither author, nor their relatives, have received money, gifts, or other compensation from any organization, institution, or business that may be affected financially by your publication.
Neither author, nor their relatives, have been employed by an organization, institution, or business that may be affected financially by your publication.
Neither author, nor their relatives, have been in a supervisory position that may be affected financially by your publication.
Neither author, nor their
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