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

NCT02185378 | Completed

• 1 other identifier: 4-2014-0302
• Study Type: interventional
• Target: 36
• Locations: 1 country
• Sites: 1

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.

Conditions

Obese Patients, One Lung Ventilation

Outcome Measures

Primary Outcomes (1)

• Changes of the intrapulmonary shunt fraction and respiratory dynamic parameter

  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

  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)

Study Arms (2)

I:E ratio 1:2

ACTIVE COMPARATOR

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

I:E ratio 1:1

ACTIVE COMPARATOR

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

Interventions

I:E ratio 1:2 PROCEDURE

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.

I:E ratio 1:2

I:E ratio 1:1 PROCEDURE

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.

I:E ratio 1:1

Eligibility Criteria

• Age: 40 Years - 80 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

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

You may not qualify if:

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

Sponsors & Collaborators

• Yonsei University: lead

Study Sites (1)

Department of Anaesthesiology and Pain Medicine, Anaesthesia and Pain Research Institute, Yonsei University College of Medicine

Seoul, 120-752, South Korea

Location

Study Officials

• Young Jun Oh, MD,PhD

  Department of Anaesthesiology and Pain Medicine, Anaesthesia and Pain Research Institute, Yonsei University College of Medicine

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NON RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR
• Purpose: OTHER
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: July 3, 2014
• First Posted: July 9, 2014
• Study Start: July 1, 2014
• Primary Completion: January 1, 2015
• Study Completion: January 1, 2015
• Last Updated: March 18, 2019

Record last verified: 2019-03

Locations

KR (1)