BODY:
Effective treatment of morbid obesity normalises cardiac risk factors and
helps improve or resolve co-morbidity states such as diabetes and obstructive
sleep apnoea. According to Mr Stephen Pollard, several studies have shown the
Roux-en-Y gastric bypass to be superior to the more traditional vertical
banded gastroplasty in achieving adequate and sustained weight loss.
Indications
* Morbidly obese patients aged 18-60 should be considered for surgery if
their body mass index (BMI) is >40, or >35 if associated with significant
obesity-related co-morbidity such as osteoarthritis, diabetes mellitus,
hypertension or obstructive sleep apnoea (BMI is calculated as weight
(kg)/height (m2)).
Contraindications
* Significant cardiac disease with an abnormal echocardiogram and extensive
psychiatric problems in the past are relative contraindications.
* Previous vertical banded gastroplasty that has failed to achieve weight
loss is not a contraindication.
Alternative treatments
* Conventional dieting will always achieve weight loss, but these patients
characteristically regain all the lost weight and often overshoot as soon as the
restriction is lifted.
* Jejuno-ileal bypass is now outlawed because of the high risk of liver
failure from malnutrition.
* Vertical banded gastroplasty has produced disappointing long-term results
in terms of function, with vomiting a frequent symptom. Weight loss is often not
maintained after the first few years due to dilation of the gastric pouch or
disruption of the staple line.
Availability
* Vertical banded gastroplasty is available at many centres, but the
gastric bypass - in spite of its proven track record in the US - is available
in only a handful of units that have a specialist interest in surgery for
obesity. St James's Hospital in Leeds is the most active UK centre, performing
50-60 cases each year. Most referrals come directly from GPs.
Pre-operative work-up
* Exclusion of underlying metabolic causes for the obesity, with thyroid,
adrenal and sex hormone estimations.
* Measurement of cholesterol and lipids.
* Selected patients undergo overnight monitoring for obstructive sleep
apnoea.
Time in hospital/off work
* Seven days in hospital.
* Three to six weeks off work depending on physical activity required.
Complication rate in best hands
* Mortality - less than 1 per cent; generally from cardiac causes.
* Significant risk of wound infection (10 per cent) and incisional hernia
formation (10 per cent).
* Leakage from or stenosis of gastroenterostomy and staple line disruption
seen in less than 2 per cent.
Success rate
* All patients will lose weight. Some 10 per cent will achieve inadequate
weight loss (defined as less than 40 per cent of their excess weight). Most
achieve loss of two-thirds of their excess in the first year and >80 per cent
after three years. Around 40 per cent will achieve and maintain their ideal
body weight.
* >90 per cent of diabetics come off insulin.
* >80 per cent of hypertensives come off all treatment.
* >90 per cent of urinary incontinent patients become continent.
Post-operative care
* Diet supervised by hospital dietitian, who must stay in contact.
* Ranitidine, 150mg per day (risk of ulceration at gastroenterostomy).
* Proprietary multivitamin supplements, one per day.
* Calcium in peri- and post-menopausal females.
* Oral zinc supplements if hair loss reported (25 per cent).
Post-operative warning signs
* Early vomiting is usually caused by poor compliance.
* Delayed vomiting after meals may suggest stenosis of gastroenterostomy.
* Weight gain - very uncommon but might suggest staple line disruption or
dilatation of gastroenterostomy.
