OBES SURG (2009) 19:1468–1470 DOI 10.1007/s11695-009-9935-2 CASE REPORT When the Brakes Came Off: Re-feeding Oedema after Deflation of a Gastric Band: A Case Report Royce P. Vincent & Simon J. B. Aylwin & Carel W. le Roux Received: 24 February 2009 / Accepted: 30 July 2009 / Published online: 13 August 2009 # Springer Science + Business Media, LLC 2009 Abstract Bariatric surgery is now the treatment of choice for morbid obesity, but is not without risk. Patients are cared for in specialised centres, but complications can present to nonspecialised centres. We describe life-threatening re-feeding oedema in a patient following routine deflation of a gastric band. Band deflation or removal may be required for various reasons, but rapid release of the band without additional supplementation of electrolytes may be dangerous due to re-feeding syndrome. Keywords Bariatric surgery . Gastric banding . Re-feeding oedema Introduction Bariatric surgery currently represents the treatment of choice for morbid obesity. Most surgical procedures are carried out in low-risk individuals and the perioperative morbidity and mortality rates are low [1]. However, as clinical experience expands the spectrum of long-term complications is becoming evident, nutritional disorders such as protein-calorie malabsorption [2], vitamin and trace element deficiencies [3] and post-prandial hypoglycaemia R. P. Vincent : C. W. le Roux (*) Department of Chemical Pathology, King’s College Hospital NHS Foundation Trust, Denmark Hill, London SE5 9RS, UK e-mail: c.leroux@imperial.ac.uk S. J. B. Aylwin Department of Endocrinology, King’s College Hospital NHS Foundation Trust, Denmark Hill, London SE5 9RS, UK [4] are increasingly recognised. In this report, we describe a patient who developed a nutrition-related disorder—re-feeding oedema—following routine deflation of a gastric band. Case Report A 23-year-old female weighing 120 kg (body mass index (BMI) of 41 kg/m2) underwent laparoscopic adjustable gastric banding primarily for reasons of body image dysphoria. She had no history of an eating disorder prior to gastric banding. Over the subsequent 12 months, she experienced reduced appetite and restriction to food ingestion due to the band and lost 75 kg to a nadir weight of 56 kg (BMI 19 kg/m2). After weight loss, she developed bulimic behaviour with binge eating and deliberate purging. During this time, her menstrual periods became infrequent. Two years after the procedure, in view of the excessive weight loss and maladaptive behaviour, she opted to have the band fully deflated. Following the deflation, her appetite and food intake increased rapidly and she was able to eat without any restriction. Five days later, she presented to the emergency department having gained 12 kg in weight, with bilateral leg swelling and lower back pain. Examination revealed severe bilateral pitting oedema of her legs extending to the abdomen and upper limbs. Biochemical analysis on admission revealed marked hypophosphataemia with a serum phosphate of 0.29 mmol/L (normal 0.8– 1.4 mmol/L), an albumin of 34 g/L (35–50 g/L), deranged liver function tests with an aspartate aminotransferase of 253 IU/L (10–50 IU/L) and gamma glutamic transpeptidase 96 IU/L (1–55 IU/L). Other investigations to exclude a pathological oedema-forming state were normal including an echocardiogram, abdominal and pelvic ultrasound scan and 24-h urine protein excretion. Re-feeding syndrome was OBES SURG (2009) 19:1468–1470 diagnosed, and she made a rapid recovery with diuretic therapy but without specific nutritional replacement and was discharged home 5 days later. Two months following this episode, the gastric band was removed which resulted in 17 kg weight gain. One year later, she weighed 75 kg (BMI 32 kg/m2). Currently, she does not have any symptoms of binge eating and her menstrual cycle is regular. Discussion Gastric banding involves the introduction of an adjustable silastic band encircling the proximal portion of the stomach with a subcutaneous port linked to the band [5]. The band can be adjusted by introducing fluid through the port, thus leading to more pressure on the gastro-oesophageal junction and a reduction in appetite [6]. The average excess weight loss in clinical practise after 2 years following gastric banding is around 50% [5]. The 136% excess weight loss in this case is beyond normal expectation and was probably due to several factors: the restriction of the band and the abnormal eating behaviour that followed. The reduction in appetite that occurs with the gastric band is reversed when the band is deflated and this can contribute to the excessive drive to consume food [6]. Re-feeding syndrome describes a clinical presentation that consists of a marked oedema and metabolic disturbances that occur as a result of reinstitution of nutrition, amongst patients who are starved or severely malnourished. Re-feeding oedema was first described in prisoners of war after the Second World War [7] and usually occurs within 4 days of re-feeding [8]. Patients can develop fluid and electrolyte disorders, especially hypophosphataemia, hypokalaemia, hypomagnesaemia along with neurologic, pulmonary, cardiac, neuromuscular and haematologic complications which can lead to mortality [8]. Most effects result from a sudden shift from fat to carbohydrate metabolism after re-feeding in combination with decreased intracellular phosphate stores. The investigations performed on admission excluded hypoalbuminaemia, cardiac failure, renal failure, chronic liver 1469 disease and obstruction to venous outflow as contributors to her generalised oedema. Prolonged starvation leads to low insulin levels, which are rapidly reversed when carbohydrates are introduced. During re-feeding, the increased secretion of insulin can result in significant oedema [9]. Insulin can promote sodium and potassium re-absorption mainly in the distal tubule and thick ascending limb of Henle’s loop which have the greatest density of insulin receptors [9, 10] as well as increase capillary permeability [10]. Specifically, insulin promotes the cell surface expression of the epithelial sodium channel [11] within the glomerular apparatus, leading to enhanced sodium re-absorption. Glucagon has also been implicated since glucagon has a natriuretic effect, and low levels favour an anti-natriuresis effect in the distal tubule [12]. During re-feeding, production of gonadotrophins, oestrogens and progestogens increase. Oestrogen has been shown to induce pronounced non-genomic endothelial dependent nitric oxide mediated vasodilation [13]. Hence, the pathogenesis of re-feeding oedema is complex. Phosphate is a major intracellular anion. Serum concentrations do not optimally assess body stores for electrolytes which are distributed intracellularly. While body stores of phosphate can be depleted by starvation, serum concentrations may appear normal [14]. Increased insulin secretion following re-feeding causes an intracellular flux of phosphate. It is also increasingly required for high-energy phosphate compounds during anabolism, especially when glucose is the major source of energy. This increased demand and the depleted phosphorus state due to starvation contributes to the severe hypophosphataemia seen in re-feeding syndrome. The major electrolyte changes that occur with re-feeding syndrome are summarised in Table 1. Conclusion Currently, gastric banding is increasingly used as a treatment option for severe-morbid obesity. Even though patients are cared for in specialised centres, complications can present after banding or reversal of banding. Band Table 1 Major electrolyte disturbances during re-feeding syndrome Electrolyte Serum concentration Mechanism Systems affected Sodium Potassium Increases Decreases Increased re-absorption in the kidney Increased demand and intracellular flux Phosphate Magnesium Decreases Decreases Increased demand and intracellular flux Increased demand and intracellular flux Cardiovascular, Cardiovascular, respiratory Cardiovascular, Cardiovascular, respiratory, neurological renal, hepatic, gastrointestinal, neuromuscular, hepatic, neuromuscular, respiratory, haematological gastrointestinal, neuromuscular 1470 deflation or removal may be required for a variety of reasons: excessive weight loss, persistent vomiting or the development of abnormal eating behaviour. Rapid release of the band without additional supplementation of electrolytes may be dangerous as re-feeding syndrome represents risk to this group of patients. Authors and contributors Vincent RP: I declare that I participated in the literature search, drafting of the paper, obtaining written consent from the patient and that I have seen and approved the final version. Aylwin SJB: I declare that I participated in drafting of the paper; critically reviewed its content and that I have seen and approved the final version. le Roux CW: I declare that I participated in drafting of the paper; critically reviewed its content and that I have seen and approved the final version. Conflicts of interest None References 1. Smith FJ, Holman CD, Moorin RE, et al. Incidence of bariatric surgery and postoperative outcomes: a population-based analysis in Western Australia. Med J Aust. 2008;189:198–202. OBES SURG (2009) 19:1468–1470 2. Malinowski SS. 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