Oxygenation Test During General Anesthesia

Morbid Obesity Clinical Trial

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?

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT01559402
• Other study ID #: Dnr 2011 / 462
• Status: Completed
• Phase: N/A
• First received: March 12, 2012
• Last updated: August 31, 2014
• Start date: March 2012
• Est. completion date: March 2014

Study information

• Verified date: August 2014
• Source: Landstinget Västmanland
• Contact: n/a
• Is FDA regulated: No
• Health authority: Sweden: Regional Ethical Review Board
• Study type: Interventional

Clinical Trial 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.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 40
• Est. completion date: March 2014
• Est. primary completion date: March 2014
• Accepts healthy volunteers: No
• Gender: Both
• Age group: 18 Years to 50 Years

Eligibility

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

Allocation: Randomized, Endpoint Classification: Safety/Efficacy Study, Intervention Model: Factorial Assignment, Masking: Single Blind (Subject), Primary Purpose: Treatment

Related Conditions & MeSH terms

• Morbid Obesity
• Obesity, Morbid

Intervention

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 carbon dioxide (CO2) level of 5 %. During emergence from anesthesia 100 % oxygen is used.
• 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.
• No CPAP and 100% oxygen
This intervention follows a standard protocol without the use CPAP during induction of anesthesia.

Locations

Country	Name	City	State
Sweden	Operationskliniken, Västmanlands sjukhus Västerås	Västerås

Sponsors (1)

Lead Sponsor	Collaborator
Landstinget Västmanland

Country where clinical trial is conducted

Sweden, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Change in peripheral O2 saturation(SpO2)during and 1 hour after anesthesia in comparison to awake before anesthesia.	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.	Change in SpO2 from 5 min before start of anesthesia, to 5 min after intubation, 5 min before extubation and 1 hour after extubation.	Yes
Secondary	Arterial blood gas values for saturation (SaO2)	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.	5 min before anesthesia, 5 min after intubation, 5 min before extubation and 1 hour after anesthesia.	Yes
Secondary	Arterial oxygen tension (PaO2)	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.	5 min before start of anesthesia, 5 min after intubation, 5 min before extubation and 1 hour after extubation.	Yes