Effect of Anesthetic Conditions on Stapling Thickness and Quality

Study Overview
=================
Brief Summary
-----------------
the excluded stomach during sleeve gastrectomy can be investigated post removal outside the patient. During stapling it is common to reduce systolic arterial blood pressure (SAP) below 100 mmHg to reduce peritoneal perfusion and have better compression. Higher intra abdominal pressures reduce also the peritoneal and mucosal perfusion and might help to improve stapling compression. Stapling compression can be evaluated by measuring stapling thickness and compare it with stomach wall thickness or by measuring leaks during leak test or better outside the patient on the excised stomach with a bursting pressure.

Detailed Description
-----------------
Patients are randomized to two groups: group standard perfusion means that the SAP is kept between 100 and 140 mmHg by adapting depth of anesthesia, by level of post expiratory pressure or by giving vasoconstriction. low perfusion group means that systolic blood pressure is kept below 100 mmHg from the first linear staple till the last by using a Clevidipine infusion to regulate the blood pressure accurate just below 100 mmHg for a short time while needed. goal directed fluid therapy using 100 ml/h fluid intravenous and extra load of fluid if pulse pressure variation > 20 % increase intra abdominal pressure (IAP) up to 20 mmHg inly during stapling and return to minimum IAP needed to achieve 3 liter workspace. The resected stomach is removed and analyzed outside the body before throwing away:

Official Title
-----------------
Impact of Low Perfusion by High Intraabdominal Pressure and Low Blood Pressure on Stapling Quality Measured as Thickness Difference Between Staples and Stomach Wall and by Bursting Pressure of Excluded Stomach

Conditions
-----------------
Gastrectomy

Intervention / Treatment
-----------------
* Procedure: low perfusion state
* Procedure: normal perfusion state


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: primary sleeve gastrectomy Exclusion Criteria: allergy to one of the drugs used intra operative liver, renal, cardiac or lung disease with limited function

Ages Eligible for Study
-----------------
Minimum Age: 18 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Diagnostic
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: low perfusion
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: low perfusion<br>fluid restriction based on the goal directed fluid therapy is maintained during the whole case and a state of low perfusion is created by reducing the systolic blood pressure below 100 mmHg by vasoactive medications like cleviprex or nicardipine, by increasing positive end expiratory pressure (PEEP) and by a very short period of a high IAP of 20 mmHg only during firing. | Procedure: low perfusion state<br>* reduce SAP below 100 mmHg<br>|
| Experimental: normal perfusion<br>Perfusion pressure is maintained above 100 mmHg with free fluid loading iv and the lowest IAP possible during the whole procedure. | Procedure: normal perfusion state<br>* maintain SAP above 100 mmHg<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| staple thickness in mm | each staple is measured with thickness monitor | on excised stomach before being discarded within 1 hour after surgery | 
| stomach thickness in mm close to staple measurement | with a constant pressure thickness is measured every 10 seconds till 1 minute | on excised stomach before being discarded within 1 hour after surgery | 
| bursting pressure in mmHg | excised stomach is inflated with air under water with increasing pressure that is recorded. At moment of first bubbles intra gastric pressure is recorded | on excised stomach before being discarded within 1 hour after surgery |