Supplemental Oxygen and Complications After Abdominal Surgery (The PROXI-trial)

Study Overview
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Brief Summary
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Aim: To investigate the effect of high intra- and postoperative oxygen concentration (80%, as opposed to normally 30%) on surgical wound infection and pulmonary complications after abdominal surgery. Background: Surgical wound infection is a common and serious complication. Tissue oxygen tension is often low after surgery and the resistance against infection depends on this factor through bacterial killing by neutrophils. Oxygen is a substrate in this reaction, and it is hypothesized that by increasing the arterial oxygen tension, the risk of surgical wound infection is reduced. Previous studies to test this hypothesis have shown entirely different results. Hence, the clinical decision between high and normal oxygen concentration is still controversial. Primary hypothesis of study: Use of 80% oxygen decreases the incidence of surgical wound infection after abdominal surgery. Secondary objectives: To investigate the effect 80% oxygen on pulmonary complications (atelectasis, pneumonia, respiratory insufficiency), second operation, mortality and length of postoperative hospitalization and admission to intensive care unit after abdominal surgery.

Official Title
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PeRioperative OXygen Fraction - Effect on Surgical Site Infection and Pulmonary Complications After Abdominal Surgery (The PROXI-trial)

Conditions
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Laparotomy

Intervention / Treatment
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* Drug: Oxygen


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 18 years or older. Laparotomy, acute or elective. In case of gynaecological surgery only if malignancy is suspected (defined as risk of ovarian malignancy index >200 or a specimen with atypical or neoplastic cells). Exclusion Criteria: Other surgery within 30 days (except surgery in local anaesthesia). Chemotherapy within 3 months. Inability to give informed consent. Inability to keep oxygen saturation above 90% without supplemental oxygen (measured preoperatively by pulse oximetry).

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: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: A<br>Fraction of inspired oxygen (FiO2) = 0.30 | Drug: Oxygen<br>* During and 2 hours after surgery<br>|
| Active Comparator: B<br>FiO2 = 0.80 | Drug: Oxygen<br>* During and 2 hours after surgery<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Surgical wound infection |  | 14 days after surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Atelectasis, pneumonia, respiratory insufficiency, second operation, mortality, length of postoperative hospitalization, admission to intensive care unit. |  | 30 days after surgery |