Comparison Between CPAP and HFJV During One-lung Ventilation in VATS

Study Overview
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Brief Summary
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This study compares two ventilatory techniques (continuous positive airway pressure vs high frequency jet ventilation) during one-lung ventilation (OLV) in video-assisted thoracic surgery (VATS). All patients were ventilated with both ventilatory techniques and parameters of gas exchange were determined through arterial blood gas test.

Detailed Description
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One-lung ventilation is mandatory during most thoracic surgery procedures. During OLV, collapsed lung develops an intrapulmonary shunt leading to arterial hypoxemia. Since arterial hypoxemia is a critical intraoperative problem, many times , anesthesiologists have to use rescue ventilation strategies on non-dependent lung to improve arterial oxygen levels. The use of continuous positive airway pressure on non-dependent lung has become the most common technique to achieve that aim. High-frequency jet ventilation on non-dependent lung may be considered as an alternative way of ventilation of the non-dependent lung during one-lung ventilation because it provides a suitable gaseous exchange while facilitating minimizing surgical field motion. However, this ventilation maneuver is rarely use by thoracic anesthesiologists. Over the last years, video assisted thoracic surgery (VATS) has become widely utilized. This surgical technique becomes even more dependent on immobilization of the operation field than open-chest thoracic procedures. There is a lack of evidence in the current literature regarding the use of HFJV in VATS. The purpose of this study is to evaluate the effects of HFJV as an alternative for the treatment of hypoxemia in VATS. One-lung ventilation is mandatory during most thoracic surgery procedures. During OLV, collapsed lung develops an intrapulmonary shunt leading to arterial hypoxemia. Since arterial hypoxemia is a critical intraoperative problem, many times , anesthesiologists have to use rescue ventilation strategies on non-dependent lung to improve arterial oxygen levels. The use of continuous positive airway pressure on non-dependent lung has become the most common technique to achieve that aim. High-frequency jet ventilation on non-dependent lung may be considered as an alternative way of ventilation of the non-dependent lung during one-lung ventilation because provide suitable gaseous exchange while facilitate minimizing surgical field motion. However , this ventilation maneuver is rarely use by thoracic anesthesiologists. Over the last years, video assisted thoracic surgery (VATS) has become widely utilized. This surgical technique becomes even more dependent on immobilization of the operation field than open-chest thoracic procedures. There is a lack of evidence in the current literature about the use of HFJV in VATS. The purpose of this study is to evaluate the effects of HFJV as an alternative for the treatment of hypoxemia in VATS.

Official Title
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Comparison Between Continuous Positive Airway Pressure and High-frequency Jet Ventilation in Nondependent Lung During One-lung Ventilation in Video-assisted Thoracoscopic Surgery

Conditions
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One-Lung Ventilation, Thoracic Surgery, Video-Assisted

Intervention / Treatment
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* Procedure: CPAP
* Procedure: HFJV


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Subject requiring one-lung ventilation Subject under video-assisted thoracic surgery Exclusion Criteria: Pregnant Emergent surgery Hemodynamic instability

Ages Eligible for Study
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Minimum Age: 18 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: Crossover Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: One-Lung Ventilation<br>During one-lung ventilation, when the chest is open, the non-dependent lung is collapsed and manipulated by the surgeon. It is the routine procedure during video-assisted thoracic surgery. | |
| Active Comparator: CPAP to non-dependent lung<br>The patient will be randomly assigned to the study arm Continuous Positive Airway Pressure (CPAP). CPAP will be applied for 20 minutes to the non-dependent lung at a pressure of 2-3cmH20 using the disposable Mallinckrodt Bronchocath CPAP system. | Procedure: CPAP<br>* A recruitment maneuver will be applied to the ventilated lung. Immediately continuous positive airway pressure, at a pressure of 2-3cmH2O will applied to the non-ventilated lung for 20 minutes by the Mallinckrodt Bronchocath Disposable CPAP system (a recognised anesthetic breathing system design for CPAP).<br>|
| Experimental: HFJV to non-dependent lung<br>The patient is randomly assigned to the study arm High-frequency jet ventilation (HFJV). HFJV will be applied for 20 minutes to the non-dependent lung with a driving pressure of a 0.6 atm, respiratory rate 100 cycles per minute using the Monsoone III Jet Ventilator (Acutronic, Hirzel, Switzerland). | Procedure: HFJV<br>* A recruitment maneuver will be applied to the ventilated lung. Immediately, high-frequency jet ventilation, with a driving pressure of 0.5 atm and a respiratory rate of 100 cycles per minute will applied to the non-ventilated lung for 20 minutes using the Monsoone III Jet Ventilator (Acutronic, Hirzel, Switzerland). Monsoone III is a recognised ventilator design for HFJV.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| PaO2/FiO2 | Ratio of the arterial oxygen partial pressure (PaO2) to the inspired oxygen fraction (FiO2) determination. Time 0 (the patient is anesthetized and being ventilated on two lungs). Time 20 minutes (patient has been ventilated on one lung for 20 minutes). Time 40 minutes (following a period of 20 minutes on one intervention arm [either CPAP or HFJV]. The patient will then enter second intervention arm). Time 60 minutes ( 20 minutes after second intervention arm [either CPAP or HFJV]) | 1 day | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| PaCO2 | Arterial carbon dioxide partial pressure determination. Time 0 (the patient is anesthetized and being ventilated on two lungs). Time 20 minutes (patient has been ventilated on one lung for 20 minutes). Time 40 minutes (following a period of 20 minutes on one intervention arm [either CPAP or HFJV]. The patient will then enter second intervention arm). Time 60 minutes ( 20 minutes after second intervention arm [either CPAP or HFJV]) | 1 day | 
| Operative field conditions | Surgeon's subjective opinion about operating conditions during the interventions: impossible surgical access, acceptable operative filed or excellent operative field). Time 20 minutes (patient has been ventilated on one lung for 20 minutes). Time 40 minutes (following a period of 20 minutes on one intervention arm [either CPAP or HFJV]. The patient will then enter second intervention arm). Time 60 minutes ( 20 minutes after second intervention arm [either CPAP or HFJV]) | 1 day | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Hypoxia, High-Frequency Jet Ventilation, Continuous Positive Airway Pressure