Effect of Different Oxygen Concentration on Postoperative Pulmonary Complications After Pulmonary Reexpansion

Effect of Different Oxygen Concentration on Postoperative Pulmonary Complications After Pulmonary Reexpansion Following One-lung Ventilation in Thoracic Surgery（DOC-PCT Trial）- A Prospective Randomized Controlled Clinical Study.

To evaluate the effect of 80% inspiratory oxygen fraction (FiO2) and 30% FiO2 on the incidence of pulmonary complications after pulmonary reexpansion following one-lung ventilation and 2-hour postoperative within the first 7 days after thoracic surgery, based on lung protective ventilation strategy.

Postoperative pulmonary complications (PPCs) account for the highest proportion (about 84%) among all the factors leading to death in thoracic surgery. High FiO2 was used in perioperative period. However, there is increasing evidence that high FiO2 in non-thoracic surgery can increase respiratory related adverse events and even mortality. The guideline also suggests that low FiO2 (30-50%) during surgery while ensuring moderate level of oxygenation would be more beneficial to the prognosis of patients. Whereas, the selection of oxygen concentration in thoracic surgery is still unclear, especially which oxygen concentration ventilation is more beneficial to reduce PPCs after pulmonary reexpansion. Strict randomized controlled clinical studies are urgently needed to verify the differences in the incidence of PPCs in patients with different oxygen concentration ventilation strategies. The study aim is to evaluate the effect of 80% FiO2 and 30% FiO2 on the incidence of pulmonary complications after pulmonary reexpansion following one-lung ventilation and 2-hour postoperative within the first 7 days after thoracic surgery, based on lung protective ventilation strategy, and to provide clinical basis for optimizing perioperative management of thoracic surgery and effectively reducing the occurrence of perioperative pulmonary complications

Inclusion Criteria:1. Elective thoracic surgery: lung surgery, esophageal surgery, mediastinal surgery, etc.; 2. One-lung ventilation: double lumen bronchial cannula or occluder is used for isolation of one lung; 3, American Society of Anesthesiology (ASA) grade I ~ III; 4, 18 years ≤ age < 80 years; 5. Estimated operation time ≥2 hours; 6. Agree to participate and sign the informed consent.

Exclusion Criteria:

1. Severe lung infection occurs within 1 month;
2. Coronary heart disease or heart failure occurs within 2 or 3 months;
3. Preoperative oxygen saturation is less than 94%; 4, Need continuous oxygen therapy; 5, BMI>35 kg/m2;

6. Pregnant women; 7. Preoperative Hb<70g/L or haematocrit<30%.