The Effect Of The CPAP On The Lung Surgery Side During OLV With The Bronchial Blocker Technique For Thoracoscopy Surgery

Objective:To observe the application effect of continuous positive airway pressure（CPAP）on the lung surgery side and the best pressure during one-lung ventilation（OLV）with the bronchial blocker（BB）technique for patients undergoing thoracoscopic lung tumor resection.Methods:120 patients,who were scheduled for thoracoscopic lung tumor resection and one lung anesthesia with the appliance of bronchial blocker,were included in this study.All patients who met the following requirements and signed informed consent were entered into the study:the body mass index（BMI）18.5²5kg/m2;aged 40⁶5yr;ASA classification I or II;no gender limitation;FEV1/FVC%>70%;no obvious abnormality in lung function;no restrictive ventilation function or obstructive ventilation function;no abnormality in cardiac function;no cardiovascular system disease,the ejection fraction>50%;no anemia and other hematological diseases;no chemotherapy or radiotherapy history.Four groups were divided according to random number table:Group A（no CPAP）,Group B（CPAP=3cm）,Group C（CPAP=4cm）and Group D（CPAP=5cm）.Group A is the normal control group,in which CPAP was not performed.3cm H₂O、4cm H₂O、5cm H₂O CPAP was respectively applied in Group B、Group C、Group D.General anesthesia induction after all patients entered the operation room.Before the pleural was open to the atmosphere,two lung ventilation was performed with the following respiratory parameters were set as tidal volume（Vt）8¹0ml/kg,respiratory rate（f）12/min,I:E1:2,to maintain PetCO2 35⁴5mmHg.Fresh gas flow rate and inspired fraction of oxygen（FiO₂）were 2 L/min and 0.8.Before the opening of the pleura,respiratory circuit and the endotracheal tube was disconnect for 2 minutes to make the lung collapse naturally then performed the BB,connected respiratory circuit and the endotracheal tube,change two lung ventilation to single lung ventilation.Respiratory parameters were set as Vt 6⁸ml/kg,f 12/min,I:E1:2.to maintain PetCO₂ 35⁴5mmHg.Fresh gas flow rate and inspired fraction of oxygen（FiO₂）were 2 L/min and0.8.The general information of patients and perioperative period were recorded.Result:1.General characteristics:there is no significant difference among the four groups in the four groups to age,height,weight,gender,PaO₂,FEV1/FVC,surgical type ratio,fluid volume and urine volume（P>0.05）.2.At 30 min when OLV,there is no statistical significance for PaO₂amang the four groups（P>0.05）.At 60 min when OLV,the PaO2 of group C and D was higher than that of Group A and B（P<0.05）;the PaO₂ did not significantly differ between A and B;and also between C and D（P>0.05）.There is no significance difference between 30 min and 60 min in Group A and B;The PaO₂ of group C and D at 60 min was significantly higher than that of 30 min（P<0.05）.3.There was no obviously lung inflation in Group A and B（P>0.05）,the rate of pulmonary segments inflation was highest in Group C,the rate of lung lobe inflation was highest in Group D,the differences between groups were statistically significant（P>0.05）.4.There was no significant difference between Group A,B and C on the influence of operator（P>0.05）,the rate of influence was highest in Group D（P<0.05）.5.The hospital stays and the number of infectionwithin 7 days shows no significant differences between the 4 groups（P>0.05）.Conclusion:4cm H₂O CPAP could effectively improve oxygenation during single lung ventilation for patients who were scheduled for thoracoscopic lung tumor resection and one lung anesthesia with the appliance of bronchial blocker.It does not affect the operation and does not increase the incidence of postoperative adverse reactions.