Postoperative Hypoxia and Body Position

Study Overview
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Brief Summary
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The study aims at investigate whether the oxygen partial pressure is improved in the prone position postoperative after abdominal surgery. Included are 50 adults operated with abdominal surgery. The Intervention is turning from supine to prone position and then back to supine position while measuring whether an improvement occurs in oxygen saturation and oxygen partial pressure, or not.

Detailed Description
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Postoperative hypoxia complicates 30% - 50% of abdominal surgeries. The cause of postoperative restrictive lung function and hypoxia is unknown. Previous studies report that oxygen partial pressure decreases by an average of 2 kPa after abdominal surgery, while carbon dioxide partial pressure is unchanged and vital capacity decreases by 35%. Patients are operated and treated in the post anesthesia care unit in the supine position. The study aims at investigate whether the oxygen partial pressure is improved in the prone position postoperative after abdominal surgery or not. Inclusion: 50 adults operated with abdominal surgery. Exclusion: Esophageal surgery, Abdominal vessel surgery. Decline participation. Intervention: turning from supine to prone position and then back to supine position again. Primary outcome: Change in oxygen saturation and oxygen partial pressure. Secondary outcome: Change in carbondioxide partial pressure Procedures: Partial blood gas is taken before surgery. On the day of surgery or the day after: starting in supine position with continuous measurements of oxygen saturation from pulse oximetry, transcutaneous carbon-dioxide partial pressure and blood gas. Then turning to prone position and then back to supine position.

Official Title
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Postoperative Hypoxia and Body Position

Conditions
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Postoperative Complications, Abdominal Surgery, Hypoxia

Intervention / Treatment
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* Other: change in body position


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Being operated within 2 in the abdomen because of upper gastrointestinal surgery, colorectal surgery, urological surgery or emergency surgery Must be able to turn from supine position to prone position in the bed Exclusion Criteria: Esophageal surgery, Abdominal vessel surgery. Decline participation.

Ages Eligible for Study
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Minimum Age: 18 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
Intervention Model: Sequential Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: From supine to prone to supine position<br>Prone position | Other: change in body position<br>* changing from supine to prone position and the back to supine<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Mean change in oxygen partial pressure in supine vs. prone position. | Oxygen partial pressure | Through study completion, an average of 1 year | 
| Mean change in oxygen saturation pressure in supine vs. prone position. | Oxygen saturation | Through study completion, an average of 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Mean change in carbon dioxide partial pressure pressure in supine vs. prone position. | Carbon dioxide partial pressure | Through study completion, an average of 1 year |