About pitfalls of patients follow-up after gastric bypass for obesity

During the follow-up of obese patients operated for gastric surgery, practitioners must be vigilant for several reasons. The semiology of the surgical complications is often misleading. Physicians may consider that because of weight loss and comorbidities improvement, the patient is cured. Moreover, the positive situation created by weight loss leads the patient to minimize symptoms and difficulties. Several clinical situations require attention and rigorous evaluation. Abdominal pain should be a warning sign of surgical complications, requiring urgent response (intestinal obstruction, internal hernia, cholecystitis). Pain semiology can guide complementary investigations such as oesogastroduodenal fibroscopy useful to diagnose anastomotic ulcers occasionally resulting in anemia. Recurrent postprandial pain evokes an internal hernia, for which exploratory laparoscopy should be discussed. Faintness is particularly frequent after gastric bypass and most often associated with postprandial hypoglycemia. Practitioners should have a higher awareness of symptoms consistent with neuroglycopenia in patients with a history of bariatric surgery. First of all, uptake of hypoglycemic drugs and neurological and cardiological causes should be eliminated. Furthermore, in the presence of fasting neuroglycopenic signs, an insulinoma must be eliminated. In the presence of hypoglycemic faintness, dietary measures (fractionated meals, low glycemic index) are necessary but not always sufficient. Treatment (acarbose, calcium channel blockers, diazoxide or octreotide) could be discussed although their effectiveness is not clearly demonstrated. Occasionally, some teams suggest surgery of the gastric pouch or distal pancreatectomy. After gastric surgery, nutritional deficiencies are common (iron and vitamin D especially). Neurological complications are rare but potentially serious such as Gayet-Wernicke encephalopathy or neuropathy, most often related to deficiencies in vitamins B1, B12 or B6. Physicians must be vigilant in case of rapid weight loss, surgical complications, intercurrent diseases, vomiting or protein malnutrition. Recent appearance of neurological signs should be treated promptly without waiting for laboratory confirmation of vitamin deficiency. The infusion of glucose after surgery must always be accompanied by a parenteral supplementation of B1 vitamin. Finally, weight curve must be carefully monitored. An unusual weight loss leads to search intercurrent diseases such as surgical complications or neoplasia and psychological disturbance. (C) 2011 Societe francaise de nutrition. Published by Elsevier Masson SAS. All rights reserved.