Oxygen Reserve Index in One-Lung Ventilation During Elective Thoracic Operations

Study Overview
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Brief Summary
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The investigators' goal is to perform an observational cohort study investigating the use of oxygen reserve index (ORi) in patients undergoing elective thoracic surgery and one-lung ventilation (OLV). For this purpose, ORi values are recorded and compared to the other collected hemodynamical and oximeter parameters. The primary hemodynamic parameters include heart rate (HR) and blood pressure (BP), while; oximeter device-related parameters include peripheral oxygen saturation, perfusion index (PI), and pleth variability index (PVI). The investigators' secondary goal is to investigate relationships between these hemodynamical and oximeter parameters using statistical analysis methods.

Detailed Description
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The main objective of this study is to investigate the possible benefits of using the oxygen reserve index (ORi) parameter during one-lung ventilation (OLV) and elective thoracic operations. For this purpose, ORi values are compared to primary hemodynamical parameters of blood pressure (BP) and heart rate (HR) and Meanwhile, a device from Masimo Inc, USA, provides oximeter-related parameters, including peripheral oxygen saturation, perfusion index (PI), and pleth variability index (PVI). The secondary objective is to investigate possible statistically significant correlations between these hemodynamical and oximeter parameters using appropriate statistical methods. The study participants are patients undergoing video-assisted thoracotomy surgical procedures (VATS) or open thoracotomy for suspicion and possible lung tumor removal. The surgical operation of either lobectomy, pneumonectomy, lung biopsy, or wedge resection is considered during this procedure. The inclusion and exclusion criteria are summarized in another section of the clinicaltrials.gov registration document. All patients in the study receive a similar anesthetic management protocol. Premedication is not required in the study. After admitting a patient to the operating theatre, pulse oximetry SpO2, electrocardiogram, and noninvasive blood pressure monitoring are established. Heart rate (HR), mean arterial pressure (MAP), systolic blood pressure (SBP), and diastolic blood pressure (DBP) are measured at certain time points. Anesthesia requires induction of anesthesia with intravenous doses of propofol (Pofol, Fresenius Pharmaceutical, Turkey), 2 to 3 mg/kg, rocuronium (Esmeron, Organon Pharmaceuticals, U.S.A.) at a dose of 0.6 mg/kg, and fentanyl (Janssen fentanyl, Janssen Pharmaceutical, Belgium) at a dose of 2 to 3 mcg/kg. Tracheal intubation requires the use of a left Robertshaw double-lumen tube. During anesthesia, one-lung ventilation (OLV) is provided to all patients in addition to mechanical ventilation. The anesthesia maintenance includes inhalational anesthetic of sevoflurane (Sevorane, Abbott Pharmaceutical, USA) at an end-tidal concentration of 1 to 2% to provide a sufficient minimum alveolar concentration to establish anesthesia and intravenous fentanyl boluses at a dose of 0.2 mcg/kg every hourly to provide analgesia and to keep mean arterial blood pressure between 60 and 80 mmHg. In addition to standard follow-up parameters, oxygen reserve index (ORi), perfusion index (PI), pleth variability index (PVI) is monitored for each patient at certain time points. Hypoxemia during OLV was defined as peripheral oxygen saturation (SpO2) value of less than 95% when the inspired oxygen fraction (FiO2)value is equal to or greater than 60% on a pulse oximetry device. Hemodynamic and oximeter data were continuously monitored. The parameters that are in need of investigation include; MAP, SBP, DBP, HR, SpO2, PaO2, ORi, PI, and PVI values. These data are monitored at thirteen different time points during the period of anesthesia induction and maintenance of the surgery. The device used in this study is called the Radical-7 Pulse CO-Oximeter device for the measurement of ORi, PI, and PVI. A correlation between these values was investigated on the continuous graphs. The duration of surgery, anesthesia, OLV, and total 100% oxygen application time are recorded. Blood gas analysis was provided at DL5 at a 5-minute time point and blood gas analysis was performed for prolonged surgeries and for surgeries with high bleeding performance that required other analysis. Routinely, patients are ventilated with 50% FiO2 (50% oxygen + 50% air mixture, 1 liter/minute fresh gas flow) after induction. The value of FiO2 rises depending on pulse oximeter values between the values of 60% and 100% in order to keep SpO2 values greater than 94. The incidence of thromboembolic complications, arrhythmia, pneumonia, the duration of hospital and intensive care unit stay is recorded.

Official Title
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Oxygen Reserve Index and Its Relations With Primary Hemodynamical and Oximeter Parameters During Elective Thoracic Surgical Operations

Conditions
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One-Lung Ventilation, Hypoxemia During Surgery, Oxygen Reserve Index, Perfusion Index, Pleth Variability Index

Intervention / Treatment
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* Device: Masimo Radical-7 Pulse CO-Oximeter


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: All patients at ages between 22 to 80 years old, American Society of Anesthesiologists Physical Status (ASA-PS) risk groups of 1 to 3 Elective thoracic surgery Operational types of thoracic surgery include; either open lung resection with thoracotomy or video-assisted thoracic surgery (VATS) operative procedure along with general a anesthesia, DLT insertion, and OLV for all patients Exclusion Criteria: Refusal to participate in a study, History of severe asthma, Severe renal and hepatic insufficiencies, Pregnancy, History of previous pulmonary resection, Hemoglobinopathies.

Ages Eligible for Study
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Minimum Age: 22 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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Arms and Interventions

| Intervention/Treatment |
| --- |
|Device: Masimo Radical-7 Pulse CO-Oximeter|The Masimo Radical-7 Pulse CO-Oximeter is a device for the measurement of pulse oximetry, oxygen reserve index (ORi), perfusion index (PI), and pleth variability index (PVI). The device is the product of a company called Masimo Inc, Irvine, CA, USA|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Main Outcome Measure-(1) | Baseline time point measurement of oxygen reserve index (ORi) equals to zero for predicting hypoxemia during one-lung ventilation | Baseline time point after patient's arrival into operating room before anesthesia induction during elective thoracic operation | 
| Main Outcome Measure-(2) | Preoxygenatiom time point measurement of oxygen reserve index (ORi) equals to zero for predicting hypoxemia during one-lung ventilation | Preoxygenation time point before anesthesia induction during elective thoracic operation | 
| Main Outcome Measure-(3) | Third time point measurement of oxygen reserve index (ORi) equals to zero for predicting hypoxemia during one-lung ventilation | Third time point during thoracic operation defined as; five minutes after tracheal intubation during two-lung ventilation in the supine position during elective thoracic operation | 
| Main Outcome Measure-(4) | Fourth time point measurement of oxygen reserve index (ORi) equals to zero for predicting hypoxemia during one-lung ventilation | Fourth time point during thoracic operation defined as; 5 minutes after placing the patient in a lateral position with two-lung ventilation during elective thoracic operation | 
| Main Outcome Measure-(5) | Fifth time point measurement of oxygen reserve index (ORi) equals to zero for predicting hypoxemia during one-lung ventilation | Fifth time point during thoracic operation defined as; at 1 minute after OLV placement during elective thoracic operation | 
| Main Outcome Measure-(6) | Sixth time point measurement of oxygen reserve index (ORi) equals to zero for predicting hypoxemia during one-lung ventilation | Sixth time point during thoracic operation defined as; at 2 minute after OLV placement during elective thoracic operation. | 
| Main Outcome Measure-(7) | Seventh time point measurement of oxygen reserve index (ORi) equals to zero for predicting hypoxemia during one-lung ventilation | Seventh time point during thoracic operation defined as; at 5 minute after OLV placement during elective thoracic operation. | 
| Main Outcome Measure-(8) | Eighth time point measurement of oxygen reserve index (ORi) equals to zero for predicting hypoxemia during one-lung ventilation | Eighth time point during thoracic operation defined as; at 10 minute after OLV placement during elective thoracic operation. | 
| Main Outcome Measure-(9) | Ninth time point measurement of oxygen reserve index (ORi) equals to zero for predicting hypoxemia during one-lung ventilation | Ninth time point during thoracic operation defined as; at 15 minute after OLV placement during elective thoracic operation. | 
| Main Outcome Measure-(10) | Tenth time point measurement of oxygen reserve index (ORi) equals to zero for predicting hypoxemia during one-lung ventilation | Tenth time point during thoracic operation defined as; at 30 minute after OLV placement during elective thoracic operation. | 
| Main Outcome Measure-(11) | Eleventh time point measurement of oxygen reserve index (ORi) equals to zero for predicting hypoxemia during one-lung ventilation | Eleventh time point during thoracic operation defined as; at 45 minute after OLV placement during elective thoracic operation. | 
| Main Outcome Measure-(12) | Twelfth time point measurement of oxygen reserve index (ORi) equals to zero for predicting hypoxemia during one-lung ventilation | Twelfth time point during thoracic operation defined as; at 60 minute after OLV placement during elective thoracic operation. | 
| Main Outcome Measure-(13) | Thirteenth time point measurement of oxygen reserve index (ORi) equals to zero for predicting hypoxemia during one-lung ventilation | Thirteenth time point during thoracic operation defined as; at 90 minute after OLV placement during elective thoracic operation. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Secondary Outcome-(1) | A correlation between ORi and peripheral oxygen saturation (SpO2), ORi and perfusion index (PI), and ORi pleth variability index (PVI) parameters that we collected during operation in patients undergoing elective thoracic surgery and one-lung ventilation (OLV) | During anesthesia induction and maintenance of elective thoracic operation | 
| Secondary Outcome-(2) | The Patients' demographic parameters and co-morbid diseases | Twenty-four hours prior to elective thoracic surgery operation | 
| Secondary Outcome-(3) | Measurement of mean arterial pressure (MAP) | During elective thoracic surgery every five minutes continuously | 
| Secondary Outcome-(4) | Measurement of systolic blood pressure (SBP) | During elective thoracic surgery every five minutes continuously | 
| Secondary Outcome-(5) | Measurement of diastolic blood pressure (DBP) | During elective thoracic surgery every five minutes continuously | 
| Secondary Outcome-(6) | Measurement of heart rate (HR) | During elective thoracic surgery every five minutes continuously | 
| Secondary Outcome-(7) | Arterial blood gas analysis during elective thoracic surgical operation | Five minutes after placing the patient in a lateral position with two-lung ventilation | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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ventilation, hypoxemia, one-lung ventilation, oxygen, perfusion