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

Study Overview
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Brief Summary
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The objective of this randomized clinical trial is to compare pain levels during and after insufflation with carbon dioxide or in subjects that will undergo endoscopic fulguration with argon to reduce the diameter of the gastrojejunal anastomosis. The investigators hypothesize that carbon dioxide will be superior in causing less pain and leading to less discomfort.

Detailed Description
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Laparoscopic gastric bypass surgery is one of the strategies oriented towards weight reduction in obese patients. Although in the short term it has a high degree of success, weight regain is common in the long term, in part due to the dilatation of the anastomosis that allows food to pass without barriers and hinders the purpose of bypass surgery. Fulguration with argon is an endoscopic technique that reduces the diameter of the anastomosis, offering resistance to food passage and improving patient outcomes. Although carbon dioxide is the current standard for laparoscopic surgery, its use for fulguration with argon as compared to ambient air has not been investigated in the setting of the stenosis of a dilated anastomosis following gastric bypass surgery. stenosis. Therefore, to investigate pain during and after this procedure, investigators will conduct a randomized clinical trial comparing carbon dioxide and ambient air. The secondary aims will be to measure the diameter of the gastrojejunal anastomosis during three endoscopic sessions and in a final control examination eight weeks after the third session; to determine whether the patient loses weight or not by the final control objective after three sessions of endoscopic fulguration with argon; to analyze if the method employed is able to reduce body weight to the minimum weight achieved after bariatric surgery;and to investigate whether there is a correlation between the percentage reduction in anastomotic diameter and the percentage loss of regained weight.

Official Title
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A Multicenter Randomized Clinical Trial of Carbon Dioxide (CO2) Versus Air Insufflation for the Application of Argon Plasma to Reduce the Gastrojejunal Anastomosis in Individuals With Weight Regain After Bypass Surgery.

Conditions
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Dilatation of Anastomosis, Bypass Complication, Obesity

Intervention / Treatment
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* Drug: Carbon dioxide
* Drug: Ambient air
* Drug: Argon fulguration


Participation Criteria
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Eligibility Criteria
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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;

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Carbon dioxide<br>Argon fulguration will be performed using CO2 for insufflation. After using a disposable endoscopic catheter, argon plasma (Argon 2) (MAE, Ribeirão Preto, Brazil) will be applied in a 1-cm band around the entire circumference of the gastrojejunal anastomosis at an intensity of 90 W and a flow rate of 2 L/min. | Drug: Carbon dioxide<br>* Carbon dioxide will be used as an insufflating gas during argon fulguration of the dilatated anastomosis.<br>* Other names: Carbon dioxide insufflation;Drug: Argon fulguration<br>* The dilatated anastomosis from the gastric bypass surgery will be reduced in diameter using fulguration with argon. Patient in both groups will be placed in the left lateral decubitus position, with anesthesia being performed exclusively using propofol; adequate cardiopulmonary monitoring will be carried out during the entire procedure. After sedation, endoscopy will be performed with an Olympus CV-180 endoscope (Olympus, Tokyo, Japan) and analysis and measurement of the anastomosis will be achieved using Raptor foreign body forceps (Endoscopy Group US, Inc., Mentor - Ohio, USA). The images will be transferred to an Olympus EvisExera II processor connected to a computer with the ZScan 5 program (Goiânia, GO, Brazil).<br>* Other names: Argon;|
| Active Comparator: Ambient air<br>Argon fulguration will be performed using ambient air for insufflation. After using a disposable endoscopic catheter, argon plasma (Argon 2) (MAE, Ribeirão Preto, Brazil) will be applied in a 1-cm band around the entire circumference of the gastrojejunal anastomosis at an intensity of 90 W and a flow rate of 2 L/min. | Drug: Ambient air<br>* Ambient air will be used as an insufflating gas during argon fulguration of the dilatated anastomosis.<br>* Other names: Ambient air insuflattion;Drug: Argon fulguration<br>* The dilatated anastomosis from the gastric bypass surgery will be reduced in diameter using fulguration with argon. Patient in both groups will be placed in the left lateral decubitus position, with anesthesia being performed exclusively using propofol; adequate cardiopulmonary monitoring will be carried out during the entire procedure. After sedation, endoscopy will be performed with an Olympus CV-180 endoscope (Olympus, Tokyo, Japan) and analysis and measurement of the anastomosis will be achieved using Raptor foreign body forceps (Endoscopy Group US, Inc., Mentor - Ohio, USA). The images will be transferred to an Olympus EvisExera II processor connected to a computer with the ZScan 5 program (Goiânia, GO, Brazil).<br>* Other names: Argon;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Pain Visual Analogue Scale | A visual scale to assess self-reported pain going from 0 to 10. | Before surgery, and after eight weeks of the first endoscopic session. The outcome will be the substraction of the initial value and the final value of pain. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in diameter of the gastrojejunal anastomosis | Analysis and measurement in millimeters of the anastomosis will be achieved using Raptor foreign body forceps (Endoscopy Group US, Inc., Mentor - Ohio, USA). | Before surgery, and after eight weeks of the first endoscopic session. | 
| Weight reduction | The final weight measured in kilograms after eight weeks of the initial surgery will be subtracted from the weight at the start of the trial | Before surgery, and after eight weeks of the first endoscopic session. |