Open Access
Feature Article

What's new in weight loss management and surgery?

Open Access
Feature Article

What's new in weight loss management and surgery?

Tamara C Preda, Veronica A Preda, REGINALD V. LORD

Figures

© animated healthcare ltd/spl/diomedia.com
© animated healthcare ltd/spl/diomedia.com
Dr Veronica Preda is a Consultant Endocrinologist at Macquarie University Hospital; and Senior Clinical Lecturer at Macquarie University, Sydney. Dr Tamara Preda is a General Surgeon at Liverpool Public Hospital, St Vincent’s and Prince of Wales Private Hospitals; and Clinical Lecturer in Surgery at the University of Notre Dame, Sydney. Professor Reginald Lord is an upper Gastrointestinal Surgeon at St Vincent’s Public and Private and Macquarie University Hospitals; and Professor and Head of Surgery at the University of Notre Dame, Sydney, NSW. Dr Veronica Preda and Professor Lord are both members of the multidisciplinary Healthy Weight Clinic at MQ Health, Macquarie University Hospital, Sydney, NSW.

Laparoscopic adjustable gastric band

Following the first successful laparoscopic placement of an adjustable gastric band in 1995, uptake rates were high and promising initial results were reported (Figure 1b). Over time, the laparoscopic adjustable gastric band (LAGB) procedure has fallen out of favour because of problems with obstruction due to ingested food being stuck at the narrow lumen of the band, gastro-oesophageal reflux, which can be severe, and other complications including band slippage, band erosion and port and tubing problems. Although many patients have long-term satisfactory weight loss and control of obesity comorbid conditions, long-term failure of weight loss in up to 62% of patients has been reported.26

Patients with inadequate weight loss may have an overly tight band, which induces consumption of soft high-energy foods and drinks. In these patients, adjustment of the band fluid to an ideal volume combined with dietary advice may be sufficient to restart weight loss. In many other patients, however, band removal is performed, followed by a different bariatric operation.

Roux-en-Y gastric bypass

RYGB is more technically demanding and metabolically disruptive than sleeve gastrectomy, with significantly higher morbidity and mortality rates. This operation results in gastric restriction and intestinal malabsorption. The procedure involves restricting the size of the stomach by stapling to create a small proximal pouch; the bypassed stomach remains in situ and is subsequently difficult to examine endoscopically. A Roux alimentary limb of jejunum is anastomosed to the gastric pouch, with the biliopancreatic juice entering the bowel 50 cm or lower at a second anastomosis (Figure 1c). Malabsorption is therefore induced by bypassing normal absorption of ingested food in the foregut. Complications include anastomotic leak, internal herniation, bowel obstruction and nutritional problems due to the malabsorption. 

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Despite the higher morbidity and mortality profile of RYGB compared with either sleeve gastrectomy or LAGB, gastric bypass should be considered in some patients, such as those with markedly severe obesity, significant gastro-oesophageal reflux disease, especially with Barrett’s disease, and those with severe type 2 diabetes. A single anastomosis variant of the bypass operation is increasingly popular; high quality longer-term follow-up data comparing it with sleeve gastrectomy or RYGB are awaited, but it seems clear that there are fewer complications with the single anastomosis bypass operation compared with RYGB.

Follow up after surgery

In the early postoperative phase, patient progress is monitored closely with dietitian input. Patients progress from a fluid-only diet, to puree and soft food, and eventually to a relatively normal diet in most over the course of two to four weeks. Some patients report permanent inability to tolerate some foods such as steak or bread, especially in those who have undergone LAGB surgery. It is important that patients remain well hydrated and that protein intake is 60 to 80 g/day, for which commercially formulated liquid very low-calorie diet meals are useful. 

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Deficiencies of many micro and macronutrients can occur postsurgery and monitoring for these should be undertaken. The most common deficiencies and patients most at risk are listed in Table 2. A typical set of blood tests for a patient who has undergone sleeve gastrectomy at six months, 12 months and annually thereafter includes a full blood count and measurement of albumin, calcium, magnesium, phosphate, folate, parathyroid hormone, 25-hydroxy vitamin D, iron, transferrin and vitamin B12 levels.