Oxygenation Test During General Anesthesia - Full Text View

Purpose

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.

Condition	Intervention
Morbid Obesity	Procedure: CPAP and 100% oxygen Procedure: CPAP and 31% oxygen Procedure: No CPAP and 100% oxygen

Study Type:	Interventional
Study Design:	Allocation: Randomized Endpoint Classification: Safety/Efficacy Study Intervention Model: Factorial Assignment Masking: Single Blind (Subject) Primary Purpose: Treatment
Official Title:	Application of Protective Ventilation Improves Oxygenation During and After Anesthesia. Is it Possible That a Special Procedure, an Oxygenation Test, Can Replace Arterial Blood Gases When Evaluating Oxygenation?

Resource links provided by NLM:

MedlinePlus related topics: Gas Obesity Oxygen Therapy

U.S. FDA Resources

Further study details as provided by Landstinget Västmanland:

Primary Outcome Measures:

Change in peripheral O2 saturation(SpO2)during and 1 hour after anesthesia in comparison to awake before anesthesia. [ Time Frame: Change in SpO2 from 5 min before start of anesthesia, to 5 min after intubation, 5 min before extubation and 1 hour after extubation. ] [ Designated as safety issue: Yes ]
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:

Arterial blood gas values for saturation (SaO2) [ Time Frame: 5 min before anesthesia, 5 min after intubation, 5 min before extubation and 1 hour after anesthesia. ] [ Designated as safety issue: Yes ]
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) [ Time Frame: 5 min before start of anesthesia, 5 min after intubation, 5 min before extubation and 1 hour after extubation. ] [ Designated as safety issue: Yes ]
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.

Estimated Enrollment:	80
Study Start Date:	March 2012
Estimated Study Completion Date:	December 2014
Estimated Primary Completion Date:	December 2014 (Final data collection date for primary outcome measure)

Arms	Assigned Interventions
Experimental: Start O2 100% and CPAP 10, end O2 100%. 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.	Procedure: CPAP and 100% oxygen During pre oxygenation and induction of anesthesia 100 % oxygen is used with a continuous positive airway pressure of 10 cmH2O, during maintenance of anesthesia a positive endexpiratory pressure of 10 cm H20 is used with controlled volume ventilation aiming at an end tidal carbondioxid (CO2) level of 5 %. During emergence from anesthesia 100 % oxygen is used. Other Name: Preventive ventilation
Experimental: Start O2 100% and CPAP 10, end O2 31%. 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.	Procedure: CPAP and 31% oxygen During pre oxygenation and induction of anesthesia 100 % oxygen is used with a continuous positive airway pressure of 10 cm H2O, during maintenance of anesthesia a positive endexpiratory pressure of 10 cm H20 is used with controlled volume ventilation aiming at an end tidal CO2 level of 5 %. During emergence from anesthesia 31 % inspiratory oxygen or the inspiratory oxygen level needed to achieve a SpO2 of at least 96 % (if 31 % oxygen is not enough), is used. Other Name: Preventive ventilation
Experimental: Start O2 100% and CPAP 0, end O2 100%. 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.	Procedure: No CPAP and 100% oxygen This intervention follows a standard protocol without the use CPAP during induction of anesthesia. Other Name: Standard protocol.

Eligibility

Ages Eligible for Study:	18 Years to 50 Years
Genders Eligible for Study:	Both
Accepts Healthy Volunteers:	No

Criteria

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

Contacts and Locations

Please refer to this study by its ClinicalTrials.gov identifier: NCT01559402

Contacts

Contact: Lennart Edmark, MD

046 21 173000

lennart.edmark@ltv.se

Locations

Sweden
Operationskliniken, Västmanlands sjukhus Västerås	Recruiting
Västerås, Sweden, 721 89
Principal Investigator: Lennart Edmark, MD

Sponsors and Collaborators

Landstinget Västmanland

Investigators

Principal Investigator:

Göran Hedenstierna, Prof.

Uppsala University Hospital

More Information

No publications provided

Responsible Party:	Lennart Edmark, Principal Investigator, Landstinget Västmanland
ClinicalTrials.gov Identifier:	NCT01559402 History of Changes
Other Study ID Numbers:	Dnr 2011 / 462
Study First Received:	March 12, 2012
Last Updated:	January 28, 2013
Health Authority:	Sweden: Regional Ethical Review Board

Additional relevant MeSH terms:

Obesity
Obesity, Morbid
Overnutrition
Nutrition Disorders
Overweight
Body Weight
Signs and Symptoms

Anesthetics
Central Nervous System Depressants
Physiological Effects of Drugs
Pharmacologic Actions
Central Nervous System Agents
Therapeutic Uses

ClinicalTrials.gov processed this record on May 23, 2013