Effects of 1:1 Inspiratory to Expiratory Ratios on Oxygenation and Intrapulmonary Shunt Fraction During One Lung Ventilation in the Obese Patients

Sponsor

Yonsei University (Other)

Overall Status

Completed

CT.gov ID

NCT02185378

Collaborator

(none)

Enrollment

Location

Arms

Duration (Months)

Patients Per Site Per Month

Study Details

Study Description

Brief Summary

One-lung ventilation, even in patients with healthy weight, causes an impairment in gas-exchange and respiratory mechanics. We hypothesized that oxygenation during the one-lung ventilation in obese patients would be improved by applying inverse-ratio ventilation, reducing atelectasis in the dependent lung and resulting in reduced shunt. Because of the restrictive ventilatory effects of obesity, these patients often show a decreased functional residual capacity and decreased expiratory reserve volume, leading to an overall decreased tidal volume. These reduction leads to arterial hypoxemia, V-Q mismatch and Rt to Lt shunting. There are few studies on the one lung ventilation in obese patients about this prolonged inspiratory time ventilatory method. We plan to investigate the effect of this ventilation method in obese patients during one lung ventilation.

Condition or Disease	Intervention/Treatment	Phase
Obese Patients, One Lung Ventilation	Procedure: I:E ratio 1:2 Procedure: I:E ratio 1:1	N/A

Study Design

Study Type:

Interventional

Actual Enrollment :

36 participants

Allocation:

Non-Randomized

Intervention Model:

Parallel Assignment

Masking:

Triple (Participant, Care Provider, Investigator)

Primary Purpose:

Other

Official Title:

Effects of 1:1 Inspiratory to Expiratory Ratios on Oxygenation and Intrapulmonary Shunt Fraction During One Lung Ventilation in the Obese Patients

Study Start Date :

Jul 1, 2014

Actual Primary Completion Date :

Jan 1, 2015

Actual Study Completion Date :

Jan 1, 2015

Arms and Interventions

Arm	Intervention/Treatment
Active Comparator: I:E ratio 1:2 We plan to evaluate the improvement on respiratory function with different ventilation I:E ratios (1:2 vs. 1:1) during the one-lung ventilation in an obese patients.	Procedure: I:E ratio 1:2 We plan to evaluate the improvement on respiratory function with different ventilation I:E ratios (1:2 vs. 1:1) during the one-lung ventilation in an obese patients.
Active Comparator: I:E ratio 1:1 The purpose of our study is to compare the effects of minimal prolonged 1:1 IE ratioventilation on respiratory mechanics and oxygenation with conventional 1:2 IE ratio ventilation during OLV in obese patients.	Procedure: I:E ratio 1:1 The purpose of our study is to compare the effects of minimal prolonged 1:1 IE ratioventilation on respiratory mechanics and oxygenation with conventional 1:2 IE ratio ventilation during OLV in obese patients.

Arm

Intervention/Treatment

Active Comparator: I:E ratio 1:2

We plan to evaluate the improvement on respiratory function with different ventilation I:E ratios (1:2 vs. 1:1) during the one-lung ventilation in an obese patients.

Procedure: I:E ratio 1:2

We plan to evaluate the improvement on respiratory function with different ventilation I:E ratios (1:2 vs. 1:1) during the one-lung ventilation in an obese patients.

Active Comparator: I:E ratio 1:1

The purpose of our study is to compare the effects of minimal prolonged 1:1 IE ratioventilation on respiratory mechanics and oxygenation with conventional 1:2 IE ratio ventilation during OLV in obese patients.

Procedure: I:E ratio 1:1

Outcome Measures

Primary Outcome Measures

Changes of the intrapulmonary shunt fraction and respiratory dynamic parameter [T1 (10min before one lung ventibation) T2 (30min after one lung ventilation started)T3 (60min after one lung ventilation started) T4 (10min after two lung ventilation)]
shunt fraction Qs/Qt = (CcO2- CaO2)/(CcO2- CvO2), CcO2 = Hgb x 1.34 x ScO2 + PcO2 x 0.003, lung compliance : Compliance= Vt / Pplat, physiologic dead space : Vd/Vt = 1.14 x (PaCO2 - PETCO2)/PaCO2- 0.005

Eligibility Criteria

Criteria

Ages Eligible for Study:

40 Years to 80 Years

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

Inclusion Criteria:

Above 40 years of age.
American Society of Anesthesiologists (ASA) Physical Status I, II, III.
Obesity (BMI >25 kg/ m2 )
thoracic surgical procedure

Exclusion Criteria:

severe functional liver or kidney disease
diagnosed HF ( NYHA class >3)
reduced pulmonary diffusion capacity < 80%

Contacts and Locations

Locations

	Site	City	State	Country	Postal Code
1	Department of Anaesthesiology and Pain Medicine, Anaesthesia and Pain Research Institute, Yonsei University College of Medicine	Seoul		Korea, Republic of	120-752

Sponsors and Collaborators

Yonsei University

Investigators

Principal Investigator: Young Jun Oh, MD,PhD, Department of Anaesthesiology and Pain Medicine, Anaesthesia and Pain Research Institute, Yonsei University College of Medicine

Study Documents (Full-Text)

None provided.

More Information

Publications

None provided.

Responsible Party:

Yonsei University

ClinicalTrials.gov Identifier:

NCT02185378

Other Study ID Numbers:

4-2014-0302

First Posted:

Jul 9, 2014

Last Update Posted:

Mar 18, 2019

Last Verified:

Mar 1, 2019

Additional relevant MeSH terms:

Respiratory Aspiration

Obesity

Study Results

No Results Posted as of Mar 18, 2019