Obesity is a complex multi-system disorder, which is increasingly
recognized as one of the greatest challenges faced by health care systems throughout
the world. Obesity is classified on the basis of both the BMI and the fat distribution.
Surgical bariatric procedures can achieve up to 50% weight loss and this is sustained
for a longer period of time. The procedures, although not without risk, are relatively
safe with low morbidity and mortality rates. A key marker for increased risk of
perioperative complications is central obesity. The presence of obstructive sleep apnoea
is an independent marker of risk that leads to the doubling of postoperative respiratory
and cardiac complications. Obese patients will have a markedly different volume of
distribution of drugs as a result of the adipose tissue. To compensate for these changes
drug dosing in obese patients is based on a combination of adjusted body weight, total
body weight, ideal body weight and lean body mass. Adequate time and preparation is
essential to provide safe conditions to anaesthetise obese patients. There are specific
considerations for the intra-operative anaesthetic management of obese individuals,
which need to be adhered to for the safe conduct and reversal of anaesthesia. Most
patients presenting for bariatric surgery can be discharged to a ward environment.
However, some patients carry an increased risk and as such may be required to be cared
for in a high dependency or an intensive care unit. In addition, a number of patients
may require specific measures for safe hospital discharge.
Keywords: Anaesthesia, Anaesthetic management, Analgesia, Bariatric surgery,
Monitoring, Obesity hypoventilation syndrome, Obstructive sleep apnoea, Postoperative
care, Respiratory function, Risk stratification scores.
