Impact of OFA During LPV on Postoperative Oxygen Saturation

Study Overview
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Brief Summary
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Opioids used intra operative increase the amount of opioids needed post operative to control post operative pain. if opioids are given post operative, we assume that more atelectasis and hypoxia takes place even after lung protective ventilation. These postoperative lower oxygen saturations will require giving more frequent oxygen therapy.

Detailed Description
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This is an observational study where the attending anesthesiologist decides to use opioid free or opioid general anesthesia based on his/her expertise. Every patient gets a lung protective ventilation and emergence from anesthesia using the principles set forward in the consensus meeting by Young C BJA 2019. A lung recruitment followed by high PEEP is given when lung compliance decreases below 40 ML/cmH20. The lowest oxygen saturation without adding oxygen therapy is noted post extubation at moment of admission in PACU, after having given an opioid as analgesic and at moment of discharge from PACU.. If post operative satuation drops below 94% oxygen therapy is given and noted.

Official Title
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Observational Study Evaluating the Impact of Opioid Free Anesthesia During Lung Protective Ventilation on Postoperative Oxygen Saturation.

Conditions
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Decreased Lung Compliance, Oxygen Requirement

Intervention / Treatment
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* Procedure: opioid anesthesia
* Procedure: opioid free anesthesia


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: major surgery where intubation with mechanical ventilation is required obese patients with BMI > 35 Exclusion Criteria: spontaneous breathing during procedure allergic to any of the drugs used in both groups severe liver, renal, cardiac or pulmonary disease

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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| opioid anesthesia<br>classical anesthesia using sufentanil to block sympathetic reactions during surgery. This decision is based on the anesthesiologist experience and not determined by the patient or procedure. | Procedure: opioid anesthesia<br>* opioid anesthesia means using sufentanil during surgery<br>|
| opioid free anesthesia<br>anesthesia using non opioids like dexmedetomidine, lidocaine, magnesium and ketamine to block sympathetic reactions during surgery. This decision is based on the anesthesiologist experience and not determined by the patient or procedure. | Procedure: opioid free anesthesia<br>* opioid free anesthesia means giving no opioids during surgery<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| oxygen requirement post operative to maintain saturation above 94% | oxygen saturation | first 24 hours post operative | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| postoperative pain | postoperative pain measured by VAS score | first 24 hours post operative | 
| postoperative opioid consumption | postoperative opioid consumption measured by morphine equivalents | first 24 hours post operative |