Nebulized Epoprostenol (FLOLAN) and Phenylephrine on One Lung Ventilation (OLV)

Study Overview
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Brief Summary
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This is a pilot study of a new use of Epoprostenol via inhalation (Epoprostenol is approved for intravenous use). The purpose of this study is to administered inhaled Epoprostenol and intravenous Phenylephrine to improve arterial oxygen tension during one-lung anesthesia either with volatile anesthesia (Sevoflurane) or with intravenous anesthesia (Propofol).

Official Title
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A Pilot Study of the Effects of Nebulized Epoprostenol (Flolan) and Systemic Phenylephrine on Arterial Oxygenation During One Lung Ventilation

Conditions
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Oxygenation During One Lung Ventilation

Intervention / Treatment
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* Drug: Inhaled Epoprostenol and phenylephrine
* Drug: Sevoflurane
* Drug: Propofol


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients undergoing esophagectomy via video assisted thoracoscopy surgery or open thoracotomy. Patients greater than eighteen years old that have the capacity to provide consent. Patients who weigh 89kg or less. Patients with a preoperative platelet count > 100,000mm3 Exclusion Criteria: Contraindication or allergy to any of the study drugs e.g. epoprostenol, phenylephrine, sevoflurane or propofol. Spirometry: Force expiratory Volume (FEV1) less than 80% predicted for age. Patients with spirometry indicative of obstructive lung disease are less likely to develop hypoxemia during OLV compared to patients with normal spirometry . These patients are likely to have a smaller treatment effect if any. A history of a bleeding diathesis. Use of a platelet inhibitor within the last seven days e.g. Aspirin, clopidogrel

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: Treatment
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Inhaled Epoprostenol, phenylephrine, sevoflurane<br>Inhaled Epoprostenol (Flolan), phenylephrine, volatile anesthesia maintenance (Sevoflurane) | Drug: Inhaled Epoprostenol and phenylephrine<br>* After 30 minutes of one-lung ventilation, Epoprostenol 50 ng/kg/min is administered via nebuliser in the anesthesia circuit with phenylephrine administered intravenously<br>* Other names: Prostacyclin;Drug: Sevoflurane<br>* Volatile maintenance anesthesia<br>|
| Other: Inhaled Epoprostenol phenylephrine & Propofol<br>Inhaled Epoprostenol (Flolan), phenylephrine and intravenous anesthesia maintenance (Propofol) | Drug: Inhaled Epoprostenol and phenylephrine<br>* After 30 minutes of one-lung ventilation, Epoprostenol 50 ng/kg/min is administered via nebuliser in the anesthesia circuit with phenylephrine administered intravenously<br>* Other names: Prostacyclin;Drug: Propofol<br>* Intravenous maintenance anesthesia<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Increase of arterial oxygen tension in mmHg, during one-lung ventilation surgery, in response to combined nebulized epoprostenol/phenylephrine treatment |  | Changes measured during surgery, from start of treatment at 30 minutes after one-lung ventilation (T30) to end of the 30 minutes treatment (T60). | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in base status in pH |  | Changes measured during surgery, from start of treatment at 30 minutes after one-lung ventilation (T30) to end of the 30 minutes treatment (T60). | 
| Differences between anesthetic technique -volatile vs. intravenous- in increase of arterial oxygen tension in mmHg, during one-lung ventilation surgery, in response to combined nebulized epoprostenol/phenylephrine treatment |  | Changes measured during surgery, from start of treatment at 30 minutes after one-lung ventilation (T30) to end of the 30 minutes treatment (T60). | 
| Changes in mean arterial blood pressure in mmHg |  | Changes measured during surgery, from start of treatment at 30 minutes after one-lung ventilation (T30) to end of the 30 minutes treatment (T60). | 
| Changes in platelet function count |  | Changes measured during surgery, from start of treatment at 30 minutes after one-lung ventilation (T30) to end of the 30 minutes treatment (T60). | 
| Changes in acid status in pH |  | Changes measured during surgery, from start of treatment at 30 minutes after one-lung ventilation (T30) to end of the 30 minutes treatment (T60). |