Expiratory and Plasma Propofol Concentration in Gastrological Surgery Patients

Study Overview
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Brief Summary
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Determination of accuracy With Edmond (reg) expiratory propofol measurement Device, compared With concommitant plasma samples of propofol

Detailed Description
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Edmon (trade mark) is a New Device from BBraun, measuring the expiratory concentration of propofol in anaesthetized patients. The investigators will test the accuracy and stability of such measurements in comparison With plasma propofol Levels. The investigators will test during target Control infusion (Marsh model) and assumed stable plasma Levels. Plasma samples of propofol will be taken for comparison With exhaled propofol.

Official Title
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Expiratory and Plasma Propofol Concentration in Bariatric and Cholecystectomy Patients

Conditions
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Bariatric Surgery Candidate, Cholecystectomy

Intervention / Treatment
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* Device: Edmon (reg), BBraun


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: • Patients admitted to Oslo University Hospital, scheduled for elective laparoscopic bariatric surgery or elective laparoscopic cholecystectomy. Both genders. Age 18-60 years, both inclusive. BMI ≥ 20 kg/m2, 10 patients with BMI 20-30, and 10 patients with BMI > 40 ASA classification I-III Exclusion Criteria: • Known hypersensitivity or other contraindication to propofol administered as Target Controlled Infusion. Patients which during a preoperative visit are deemed not to tolerate propofol bolus or infusion as administered by Target Controlled Infusion. Ongoing neuroleptic medication.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 60 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: Supportive Care
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: One Group of morbidly obese patients for bariatric surgery One Group of normal weight cholecystectomy
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Bariatric surgery<br>Patients due for bariatric surgery, BMI > 30 | Device: Edmon (reg), BBraun<br>* exhaled propofol will be compared With plasma propofol values<br>* Other names: propofol plasma sample;|
| Experimental: Cholecystectomy<br>Normal weight patients due for cholecystectomies | Device: Edmon (reg), BBraun<br>* exhaled propofol will be compared With plasma propofol values<br>* Other names: propofol plasma sample;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| exhaled propofol concentration | parts per billion | start of anaesthesia to end of anaesthesia, 2-3 hours in total | 
| propofol plasma concentration | microg pr ml | 4-6 samples in the period between start and end of anaesthesia | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| calculated plasma concentration | Marsh model prediction, microg pr ml | From start of anaesthesia until end of anaesthesia, 1-3 hrs in total | 
| BIS | Bispectral index value, score = 0-100 | from start of anaesthesia until end of anaestheisa, 1-3 hours in total | 
| calculated effect site concentration | Marsh model, microg pr ml | from start of anaesthesia until end of anaesthesia, 1-3 hours in total | 
| EEG Power spectrum | Spectral edge value (Hz) | f | 
| EEG Power distribution | % representation relative Power of Alpha, Beta, Theta, Gamma band | from start of anaesthesia until end of anaesthesia, 1-3 hours in total |