Oxygenation Test During General Anesthesia

Not Applicable

Completed

• Conditions: Morbid Obesity
• Interventions: Procedure: CPAP and 100% oxygen; Procedure: No CPAP and 100% oxygen; Procedure: CPAP and 31% oxygen

• Registration Number: NCT01559402
• Lead Sponsor: Region Västmanland

Brief Summary

The study investigates if applying a special ventilatory strategy during anesthesia for laparoscopic gastric by pass, produces less atelectasis and better oxygenation in spite of using 100 % oxygen during pre oxygenation and induction of anesthesia. The study investigates oxygenation with blood gas samples but also with a new method that might give more information without the use of blood gas samples.

Primary: Oxygenation in patients with morbid obesity improves if preoxygenation, induction and maintenance of anesthesia is performed with either a continuous positive airway pressure (CPAP) or a positive end expiratory pressure (PEEP), respectively, of 10 cm H2O, in comparison to a technique without CPAP but with a PEEP of 10 cm H2O.

Secondary: The improved oxygenation during anesthesia can be prolonged inte the postoperative period if emergence from anesthesia is performed without high levels of oxygen.

Detailed Description

Not available

Study Timeline

• Study Start: 2012-03
• Study First Submitted: 2012-03-12
• Study First Submitted QC: 2012-03-19
• Study First Posted: 2012-03-21
• Primary Completion: 2014-03
• Study Completion: 2014-03
• Status Verified: 2014-08
• Last Update Submitted: 2014-08-31
• Last Update Posted: 2014-09-03

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 40

Inclusion Criteria

• Adult patients scheduled for elective surgery of Morbid Obesity.
• ASA 1-2. (ASA = American Society of Anesthesiologists classification).
• "Body mass index" (BMI) ≥ 35 but < 50

Exclusion Criteria

• "ASA 3"
• Anticipated difficult intubation.
• Major bleeding.
• Problems with ventilation necessitating protocol aberrations.
• Obstructive sleep apnea syndrome with CPAP treatment at home.
• Angina Pectoris

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: FACTORIAL

Arm && Interventions

Group	Intervention	Description
Start O2 100% and CPAP 10, end O2 100%.	CPAP and 100% oxygen	This arm describes some aspects of ventilation during anesthesia for laparoscopic gastric bypass. Pre-oxygenation is with an inspiratory oxygen fraction(FIO2) of 1.0, supplied by a continuous positive airway pressure of 10 centimeters of water(cmH2O), during anesthesia a positive end-expiratory pressure of 10 cmH2O is used and during emergence from anesthesia a FIO2 of 1.0 is used. The intervention associated with this arm is labeled CPAP and 100% oxygen.
Start O2 100% and CPAP 0, end O2 100%.	No CPAP and 100% oxygen	This arm describes some aspects of ventilation during anesthesia for laparoscopic gastric bypass. Pre-oxygenation is with a FIO2 of 1.0, without a continuous positive airway pressure, during anesthesia a positive end-expiratory pressure of 10 cmH2O is used and during emergence from anesthesia a FIO2 of 1.0 is used. The intervention associated with this arm is labeled No CPAP and 100% oxygen.
Start O2 100% and CPAP 10, end O2 31%.	CPAP and 31% oxygen	This arm describes some aspects of ventilation during anesthesia for laparoscopic gastric bypass. Pre-oxygenation is with a FIO2 of 1.0, supplied by a continuous positive airway pressure of 10 cmH2O, during anesthesia a positive end-expiratory pressure of 10 cmH2O is used and during emergence from anesthesia a FIO2 of 0.3 is used. The intervention associated with this arm is labeled CPAP and 31% oxygen.

Primary Outcome Measures

Name	Time	Method
Change in peripheral O2 saturation(SpO2)during and 1 hour after anesthesia in comparison to awake before anesthesia.	Change in SpO2 from 5 min before start of anesthesia, to 5 min after intubation, 5 min before extubation and 1 hour after extubation.	During anesthesia SpO2 is measured at three different levels of oxygen; 21, 26 and 31 % respectively as long as SpO2 does not go lower than 87 % and compared to SpO2 immediately before anesthesia. SpO2 breathing air one hour after anesthesia is compared to SpO2 before anesthesia.

Secondary Outcome Measures

Name	Time	Method
Arterial blood gas values for saturation (SaO2)	5 min before anesthesia, 5 min after intubation, 5 min before extubation and 1 hour after anesthesia.	During anesthesia SaO2 is measured at three different levels of oxygen; 21, 26 and 31 % respectively as long as SpO2 (sic! does not go lower than 87 % and compared to SaO2 immediately before anesthesia. SaO2 breathing air one hour after anesthesia is compared to SaO2 before anesthesia.
Arterial oxygen tension (PaO2)	5 min before start of anesthesia, 5 min after intubation, 5 min before extubation and 1 hour after extubation.	During anesthesia PaO2 is measured at three different levels of oxygen; 21, 26 and 31 % respectively as long as SpO2 (sic) does not go lower than 87 % and compared to PaO2 immediately before anesthesia. PaO2 breathing air one hour after anesthesia is compared to PaO2 before anesthesia.

Trial Locations

Locations (1)

Operationskliniken, Västmanlands sjukhus Västerås; 🇸🇪 Västerås, Sweden