Effect Of One-lung Ventilation Strategy On Postoperative Pulmonary Complications In Patients With TV-assisted Thoracoscopy Pneumonectomy

Objective:One-lung ventilation strategy with high end-expiratory pressure（PEEP）and low tidal volume during surgery whether reduced that the incidence of postoperative pulmonary complications（PPCs）after TV-assisted thoracoscopy pneumonectomy in lung cancer patients with ARISCAT Score≥26.Methods:Sixty-eight cases of lung cancer patient with ARISCAT Score≥26,who underwent TV-assisted thoracoscopy pneumonectomy were selected for analysis with randomized,single-blind and controlled trial in Cancer Hospital of Guangxi Medical University.Thirty-three cases in the group of high PEEP were set during one-lung ventilation with tidal volume of 5 ml/kg under the predicted weight,and 10 cm H₂O of the intraoperative PEEP.Thirty-five cases in the group of low PEEP were received conventional protective ventilation during one-lung ventilation with tidal volume of 6 ml/kg at predicted body weight,and PEEP of 5 cm H₂O during the procedure.Respiratory frequency of all patients in two groups were 12 to 18 breaths per minute,with the ratio of inhalation and exhalation were 1:2.The respiratory frequency were adjusted to maintain the end-expiratory carbon dioxide partial pressure between 35 to55mm Hg,the fraction of inhaled oxygen concentration were 1.0,and lung recruitment were performed at the same time.The main end point indicators were PPCs that occurred within 7 days after surgery,including atelectasis,pneumonia,acute respiratory distress syndrome（ARDS）,and aspiration pneumonia.Secondary outcome measures included that duration of intensive care unit（ICU）,postoperative hospital stay,and 30-day mortality.One ml of whole blood were taken from the radial artery of the patients and blood gas analysis as follows:before the operation（T1）,15 minutes after the one-lung ventilation（T2）,and before the end of operation（T3）respectively.The partial arterial carbon dioxide pressure（Pa CO₂）,oxygenation index（Pa O₂/Fi O₂）,the mean arterial pressure（MAP）and heart rate（HR）were recorded at three time points respectively.The blood loss,urine volume,fluid volume and duration in the operative patients were also recorded respectively.Results:Thirteen cases of them（19.1%）occurred that pulmonary complications as follows:pneumonia,atelectasis,ARDS,and aspiration pneumonia within 7days of surgery respectively.The two lung protection strategies had different prognosis for patients undergoing thoracic surgery.The incidence of PPCs in the group of high PEEP were 9.1%,and the incidence of PPCs in the group of low PEEP were 28.5%,the probability of complications in the high PEEP group were lower significantly（P<0.05）.No cases of ARDS or aspiration pneumonia occurred that in either group.Postoperative pneumonia occurred that in 6 cases of them（17.1%）in the low PEEP group,and 3 cases of them（9.1%）in the group of high PEEP respectively.There were no significant difference between the patients in two groups（P>0.05）.No cases of atelectasis occurred in the group of high PEEP after surgery,but 4 cases of atelectasis（11.4%）in the group of low PEEP,and the difference were statistically significant between the two groups（P<0.05）.There were no differences in ICU resuscitation time,postoperative hospital stay or mortality between the patients in two groups.Conclusion:The use of lower tidal volume combined with higher PEEP and alveolar recruitment during single-lung ventilation can significantly reduce the incidence of pulmonary complications after TV-assisted thoracoscopic pneumonectomy in lung cancer patients with ARISCAT Score≥26,and that were helpful for improve intraoperative lung oxygenation function in the patients.