Carbon Dioxide Versus Air Insufflation for the Application of Argon Plasma to Reduce the Gastrojejunal Anastomosis

Inclusion Criteria: * Regain of at least 10.0% of the minimum weight reached after the gastric bypass; * Ability to understand study procedures; * Signed the informed written consent form; * Possible to complete all the stages of the study. Exclusion Criteria: * Presence of very tight restrictive ring preventing the advancement of the endoscopy device; * Stenosis of the anastomosis preventing the progression of the endoscopy device before the end of the three endoscopic sessions; * History of liver diseases such as cirrhosis or chronic active hepatitis; * Patients who required anticoagulant therapy with the exception of antiplatelet agents; * Pregnant women or those intending to become pregnant within 12 months after fulguration with argon; * Participant in another ongoing clinical research; * Recent history of neoplasia (less than 5 years); * Alcoholism or drug use; * HIV positive; * Unbalanced or uncontrollable psychiatric disorders; * Anemia or severe nutritional deficiencies; * Allergy to anesthetic compounds; * Impossibility to return within defined periods for consultations and endoscopic sessions of fulguration with argon; * Inability to follow nutritional guidelines after each endoscopic session; * Inability to understand study procedures;