Laryngeal Mask Airway in Lower Abdominal Surgery

Study Overview
=================
Brief Summary
-----------------
We measure in this study lung function of 100 patients immediately after major lower abdominal surgery. We compare lung function, when either endotracheal intubation, or laryngeal masks are used for airway protection during surgery. The hypothesis is that the use of laryngeal masks is associated with less impairment of lung function in the immediate postoperative phase.

Official Title
-----------------
Comparison of Lung Function in Patients After Lower Abdominal Surgery Exceeding 2hrs Under the Use of Laryngeal Mask vs. Endotracheal Tube for Airway Management

Conditions
-----------------
Major Lower Abdominal Surgery

Intervention / Treatment
-----------------
* Device: Laryngeal mask with gastric access
* Device: Endotracheal tube


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria - patients scheduled for elective retropubic radical prostatectomy Exclusion Criteria: - increased risk of aspiration due to hiatal hernia, morbid obesity, or facial malformations

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

Sexes Eligible for Study
-----------------
Male

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

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

Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Endotracheal Intubation<br>Clinical routine for longer lasting procedures | Device: Endotracheal tube<br> <br> |
| Experimental: Laryngeal Mask<br>Laryngeal mask with gastric access and drainage as airway management instead of endotracheal intubation | Device: Laryngeal mask with gastric access<br> <br> |

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

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The change between pre- and postoperative forced expiratory volume in one second (FEV1) in lung function | The lung function is quantified by using Spirometry and pulse oximetry. Spirometry is performed in a standardized way according to the recommendations of the American Thoracic Society (ATS) and European Respiratory Society (ERS) | one day prior to surgery, 1 hour after surgery (recovery room), at day one after surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Vital capacity (VC) measured by spirometry. | Spirometry is performed in a standardized way according to the recommendations of the American Thoracic Society (ATS) and European Respiratory Society (ERS) | one day prior to surgery, i hour after after surgery (recovery room), at day one after surgery | 
| Forced vital capacity (FVC) |  | one day prior to surgery, one hour after surgery (recovery room), at day one after surgery | 
| mid-expiratory flow (MEF 25, 50, 75) |  | one day prior to surgery, one hour after surgery, at day one after surgery | 
| Peak expiratory flow (PEF) |  | one day prior to surgery, one hour after surgery (recovery room) , at day one after surgery |