Effect of Anesthetics on Oxygenation and Microcirculation During One-lung Ventilation

Study Overview
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Brief Summary
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One-lung ventilation during thoracic surgery may affect systemic oxygenation and peripheral microcirculation by hypoxic pulmonary vasoconstriction. Both intravenous and inhalational anesthetics can be used during one-lung ventilation. However, there is still a controversy which anesthetic would be more appropriate during one-lung ventilation in the perspective of oxygenation and microcirculation. The investigators hypothesized that intravenous and inhalational anesthetics may affect oxygenation and microcirculation differently during one-lung ventilation.

Detailed Description
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Patients undergoing thoracic surgery including one-lung ventilation will be randomized to receive intravenous (propofol) or inhalational (desflurane) anesthetic. Systemic oxygenation can be evaluated by measuring partial pressure of oxygen in arterial blood analysis. Microcirculatory parameters can be obtained from vascular occlusion test. Among those parameters, recovery slope during vascular occlusion test is known to reflect recruitment of microvasculature in response to hypoxic or ischemic insult. In this study, we will compare arterial partial pressure of oxygen and recovery slope during one-lung ventilation between propofol and desflurane group.

Official Title
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Effect of Anesthetics on Oxygenation and Microcirculation During One-lung Ventilation

Conditions
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Mechanical Ventilation Complication

Intervention / Treatment
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* Drug: propofol
* Drug: desflurane


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: undergoing thoracic surgery including one-lung ventilation Exclusion Criteria: refuse to enroll BMI over 30 kg/m(2) severe obstructive or restrictive lung disease preoperative supplemental oxygen, intubated, or mechanical ventilatory support preoperative arterial partial pressure of oxygen < 60 mmHg pregnancy history of coronary artery disease preoperative continuous infusion of vasopressor or inotropes cannot undergo vascular occlusion test: anatomical abnormality of both arms, severe peripheral vascular disease, presence of A-V fistula

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 90 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: propofol<br>Propofol is used as a maintenance anesthetic to patients in the propofol group. Intervention: propofol infusion by target-controlled infusion for maintaining anesthesia propofol (Fresofol MCT 2%) target effect site concentration: 4 5 mcg/ml, during general anesthesia | Drug: propofol<br>* Patients are randomized to receive intravenous anesthetic (propofol) or inhalational anesthetic (desflurane) as a maintenance anesthetic.<br>* Other names: propofol (Fresofol(R)2 MCT 2%, Fresenius Kabi);|
| Experimental: desflurane<br>Desflurane is used as a maintenance anesthetic to patients in the desflurane group. Intervention: Desflurane administration for maintaining anesthesia desflurane (Suprane) inhalation as 6 8 vol% during general anesthesia | Drug: desflurane<br>* Patients are randomized to receive intravenous anesthetic (propofol) or inhalational anesthetic (desflurane) as a maintenance anesthetic.<br>* Other names: desflurane (Suprane(R), Baxter Healthcare);|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| arterial partial pressure of oxygen | Primary outcome is arterial partial pressure of oxygen 30 min after one-lung ventilation during thoracic surgery in propofol and desflurane groups. | 30 min after one-lung ventilation | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| recovery slope | Secondary outcome is recovery slope measured by vascular occlusion test 30 min after one-lung ventilation during thoracic surgery in propofol and desflurane groups. | 30 min after one-lung ventilation | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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oxygenation, microcirculation, one-lung ventilation, thoracic surgery