Bariatric Surgery – The GP as Gatekeeper – A GP's Perspective

Given the exponential rate of these procedures, we also have a duty to maintain a level of awareness of the potential short and long term complications unique to this set of patients.¹

We all know examples of the heart sink morbidly obese patient, the chronic diabetic, the desperate infertile young woman with polycystic ovarian syndrome or the middle-aged chronic osteoarthritic patient who is too overweight to receive a new hip or knee. The improvement in these patients’ quality of life from bariatric procedures is inarguable. This visible and often dramatic change encourages others, often less suitable, to consider a surgical weight reduction option – but at what cost? Are we doing our patients a service or disservice when we refer them for a bariatric procedure? And what should we be aware of to provide optimum care for these patients post procedure?

Each bariatric surgical procedure carries its own set of pros and cons which need to be carefully considered in selecting patients. The commonly known “lap band” procedure has been mostly accepted in this country to date.² This is due to its relatively low immediate peri-operative risk compared to its counterparts. However it produced the lowest percentage weight loss and highest re-operative rates, mainly due to band migration/slippage (15-20%), erosion (4%), unsatisfactory weight loss and untreatable reflux.^3,4,5 Additionally, the burden of lifelong follow up with the band should be considered, along with patient-reported reduced quality of life. It is well known that many patients abandon the weight control benefits of having saline in the band completely, due to its significant impact on their lifestyle. It is noteworthy that the success of the band is directly linked with the quality of long term post-operative care.⁵

This is important, from a GP perspective, when considering whether to refer for bariatric procedures and to whom. This is because all surgical interventions carry short and long term risks which, when balanced against positive outcomes, is clear for morbidly obese patients only, i.e. a BMI > 40, or 35 with associated co-morbidities, who are referred to practitioners who actively promote long term follow up.^{3, 4, 5} This is particularly relevant when considering patients who are close to these cutoffs or whose co-morbidities could be considered “soft”. Helping patients adjust their expectations of bariatric surgery and improve their understanding of the relevant procedures is important prior to referral.

Lifelong follow up and increased awareness of complications is equally important at a General Practice level. New data published in the Medical Journal of Australia highlights the unique nutritional requirements of this set of patients and, as the primary provider of ongoing care for many bariatric patients, GPs have an important role in monitoring nutritional levels and providing appropriate advice.⁶

A recent Coronial case highlighted some of the long term serious complications unique to this set of patients. A middle-aged woman died 21 months after lap band surgery, following a bout of protracted vomiting, despite being seen by a GP in the days leading up to her death.⁷ The Coroner determined that this likely preventable death was contributed to by the GP’s lack of understanding of the seriousness of prolonged vomiting in this patient population and the misperception by the patient herself that vomiting was quite normal following bariatric procedures. The severe force of vomiting had caused herniation of the stomach through the band, obstructing its blood supply and causing gastric necrosis, respiratory aspiration and rapid death.

Before we simply put a letter of referral together, it is our duty to inform ourselves and our colleagues of the overall long and short term risks and benefits of the available procedures, and to carefully consider the health outcomes for our patients. We must also remember that the real medicine is in the follow up – the science of maintaining behavioural change.

Dr Natalie Sumich, General Practitioner
WA PMLC Member, MDA National

View a Physician’s perspective – Bariatric surgery: Is There Anything New – provided in this edition of Defence Update. You can also read the Anaesthetist’s and Bariatric Surgeon’s perspectives.

References
1. Australian Institute of Health and Welfare. Weight Loss Surgery in Australia. Canberra: AIHW, 2010. (AIHW Cat. No. HSE 91.) Available at: aihw.gov.au/publication-detail/?id=6442472385&tab=2.
2. Brown, W. Bariatric Surgery Works, We Just Need to Ensure it’s Safe, 7 June 2012. Available at: theconversation.com/bariatric-surgery-works-we-just-need-to-ensure-its-safe-6756.
3. Carlin AM et al. The Comparative Effectiveness of Sleeve Gastrectomy, Gastric Bypass, and Adjustable Gastric Banding Procedures for the Treatment of Morbid Obesity. Annals of Surgery 2013; 257(5):791-7.
4. Chang S et al. The Effectiveness and Risks of Bariatric Surgery: An Updated Systematic review and Meta-analysis, 2003-2012. JAMA Surgery 2014;149(3):275-87.
5. O’Brien E et al. Long-term outcomes after bariatric surgery: fifteen-year follow-up of adjustable gastric banding and a systematic review of the bariatric surgical literature. Ann Surg 2013;257(1):87-94.
6. Guidelines Fall Short on Bariatric Surgery. Dixon J. MJA 2014;200(8):459-60.
7. Vicker, E. Record of Investigation of Death: Coroner’s Case. 5-6 March 2013. Available at: coronerscourt.wa.gov.au/_files/Levissianos_finding.pdf.