Effects of Different Oxygen Concentrations on Pulmonary Complications in Patients Undergoing Radical Resection of Esophageal Cancer

Study Overview
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Brief Summary
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Radical operation of esophageal cancer is complicated and traumatic, and ventilation with one lung in lateral position and ventilation with both lungs after supine position requires long-term tracheal intubation and ventilator-assisted ventilation, and the incidence of postoperative pulmonary complications is high.

Detailed Description
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Therefore, we should explore the most appropriate lung protection ventilation strategy to reduce the occurrence of pulmonary complications. The recommended standard of international expert group on lung protective ventilation strategy points out that the lowest concentration of oxygen (≤40%) should be inhaled as much as possible during mechanical ventilation to maintain normal blood oxygen level (SpO2≥94%). If the mixed gas with low inhaled oxygen concentration can achieve ideal oxygen saturation and arterial oxygen partial pressure, it may reduce the postoperative pulmonary complications of the subjects. However, there are few reports on the influence of different oxygen concentrations on pulmonary complications in patients undergoing radical resection of esophageal cancer. This study intends to explore the influence of different oxygen concentrations on pulmonary complications in patients undergoing radical resection of esophageal cancer.

Official Title
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Effects of Different Oxygen Concentrations on Pulmonary Complications in Patients Undergoing Radical Resection of Esophageal Cancer

Conditions
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Atelectasis, Postoperative

Intervention / Treatment
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* Drug: 30%Oxygen
* Drug: 60%Oxygen


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: American Association of Anesthesiologists (ASA) patients with I-II physical condition; Patients with preoperative partial pressure of blood gas and oxygen greater than 80mmHg who were scheduled for elective esophageal cancer surgery were operated in the right lateral position first and then in the supine position. Exclusion Criteria: there is a history of acute lung injury with acute respiratory distress syndrome within three months; Heart failure (classified by new york Heart Association) is greater than grade IV, there is a serious liver and kidney dysfunction (children with grade B or C liver failure, glomerular filtration rate < 30 ml/min); Body mass index > 30kg/m2； coagulation dysfunction; Patients receiving neoadjuvant chemotherapy; Operation time exceeds 10h The amount of bleeding is more than 800ml, and the total fluid volume is more than 3000ml.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 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: Experimental: 30% Oxygen<br>Before anesthesia induction, the participants inhaled pure oxygen through the mask for 5 minuets. After successful anesthesia induction, FiO2 will be adjusted to 60% in one lung ventilation and 30% FIO2 in both lungs ventilation, and the total gas flow rate will be set at 2L/min. All patients will be performed via the lung protective ventilation strategy. The respiratory parameters are VT: 6-8ml/kg, PEEP: 6-8 cm H2O, RR: 1:2. Manual lung recruitment maneuvers will be performed after tracheal intubation and before tracheal extubation, however when intraoperative oxygen saturation is less than 92% the manual lung recruitment maneuver will be done too. Arterial blood will be collected for blood gas analysis. Patients in both groups will be extubation the operating room and then sent to the PACU. patients should transfer to 60% Oxygen group if intraoperative oxygen saturation less than 85%. | Drug: 30%Oxygen<br>* 60%FiO2 in one lung ventilation and 30% FIO2 in both lungs ventilation<br>|
| Placebo Comparator: Experimental: 60% Oxygen<br>Before anesthesia induction, the participants inhaled pure oxygen through the mask for 5 minutes. After successful anesthesia induction, FiO2 will be adjusted to 100% in one lung ventilation and 60% FIO2 in both lungs ventilation, and the total gas flow rate will be set at 2L/min. All patients will be performed via the lung protective ventilation strategy. The respiratory parameters are VT: 6-8ml/kg, PEEP: 6-8 cm H2O, RR: 1:2. Manual lung recruitment maneuvers will be performed after tracheal intubation and before tracheal extubation, however when intraoperative oxygen saturation is less than 92% the manual lung recruitment maneuver will be done too. Arterial blood will be collected for blood gas analysis. Patients in both groups will be extubation the operating room and then sent to the PACU. | Drug: 60%Oxygen<br>* 100%FiO2 in one lung ventilation and 60% FIO2 in both lungs ventilation<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| the occurrence of atelectasis | The primary outcome is the occurrence of atelectasis scanned by computerized tomography in the operating room within 40 minutes after awakening | On the operating room within 40 minutes after awakening | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| oxygenation index | The secondary outcome is the comparison of the oxygenation index between the two groups, which is calculated and compared from the results of intraoperative blood gas analysis | On the operating room within 40 minutes after awakening |