Heated Circuit for One-lung Ventilation

Study Overview
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Brief Summary
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One-lung ventilation interrupts oxygenation. The effect of heated humidifed breathing circuit on arterial oxygenation during one-lung ventilation has not been investigated. The investigators will investigate the effect of the heated humidifed breathing circuit on oxygenation during one-lung ventilation in patients undergoing thoracoscopic surgery.

Official Title
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Effect of Heated-humidified Circuit on Arterial Oxygenation in Patients Undergoing One-lung Ventilation for Thoracoscopic Surgery

Conditions
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One-lung Ventilation, Oxygenation, Temperature

Intervention / Treatment
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* Device: Heated and humidified breathing circuit on
* Device: Heated and humidified breathing circuit off


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: American Society of Anesthesiologist class I-II Patients scheduled for one-lung ventilation for thoracoscopic surgery Exclusion Criteria: Obesity Severe obstructive or restrictive lung disease Preoperative oxygen supply Preoperative intubated state or under mechanical ventilatory support Baseline arterial partial pressure of oxygen (PaO2) < 70 mmHg Symptomatic coronary or peripheral arterial disease Renal failure Preoperative continuous infusion of inotropes or vasopressor Pregnancy

Ages Eligible for Study
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Minimum Age: 19 Years
Maximum Age: 80 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: Supportive Care
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Control<br>Heated breathing circuit will turned off. | Device: Heated and humidified breathing circuit off<br>* Heated and humidified breathing circuit will be turned off.<br>|
| Experimental: Heat<br>Heated breathing circuit will be turned on. | Device: Heated and humidified breathing circuit on<br>* Heated and humidified breathing circuit will be turned on.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Arterial oxygenation | Arterial oxygenation (mmHg) will be measured by arterial blood analysis. | At 30 minutes after one-lung ventilation | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Arterial oxygenation | Arterial oxygenation (mmHg) will be measured by arterial blood analysis. | At 0, 15, 45, and 60 minutes after one-lung ventilation | 
| Mean arterial pressure | Mean arterial pressure (mmHg) will be measured. | At 0, 15, 30, 45, and 60 minutes after one-lung ventilation | 
| Heart rate | Heart rate (beats/min) will be measured. | At 0, 15, 30, 45, and 60 minutes after one-lung ventilation | 
| Temperature | Body temperature (°C) will be measured. | At 0, 15, 30, 45, and 60 minutes after one-lung ventilation | 
| Central venous pressure | Mean central venous pressure (mmHg) will be measured by a central venous catheter. | At 0, 15, 30, 45, and 60 minutes after one-lung ventilation | 
| Cardiac index | Cardiac index (l/min/m^2) will be measured by pulse-contour analysis. | At 0, 15, 30, 45, and 60 minutes after one-lung ventilation | 
| Pressure peak | Peak pressure of ventilation (cmH2O) will be measured. | At 0, 15, 30, 45, and 60 minutes after one-lung ventilation | 
| Pressure plateau | Plateau pressure of ventilation (cmH2O) will be measured. | At 0, 15, 30, 45, and 60 minutes after one-lung ventilation | 
| Arterial carbon dioxide | Arterial carbon dioxide will be measured. | At 0, 15, 30, 45, and 60 minutes after one-lung ventilation | 
| Arterial blood acidosis | Arterial blood acidosis will be measured. | At 0, 15, 30, 45, and 60 minutes after one-lung ventilation | 
| Oxygen saturation of arterial blood | Oxygen saturation of arterial blood (%) will be measured. | At 0, 15, 30, 45, and 60 minutes after one-lung ventilation |