Effect Of Hypoxic Preconditioning Before One-lung Ventilation On Oxygenation In Patients Undergoing Lobectomy

Objective:To investigate the effect of hypoxic preconditioning（HPC）before one-lung ventilation on oxygenation in patients undergoing lobectomy.Methods:Select 58 patients who underwent elective lobectomy in our hospital.They were divided into treatment group（P group）and control group（N group）according to the random number table,with 29 cases in each group.After anesthesia-induced intubation and before one-lung ventilation（OLV）,hypoxia in group P reduced SpO₂ to 90%,and then reoxygenation increased SpO₂ to 100%,and continued ventilation for 3minutes,repeated twice The arterial blood gas was measured at the end of each treatment,and the hypoxia tolerance time of SpO₂ from 100%to 90%was recorded.Group N was subjected to routine ventilation.Radial arterial and internal jugular vein blood were measured for blood gas measurement and intrapulmonary shunt rate（Qs/Qt）before and after OLV（T0）,OLV30min（T1）,OLV 60min（T2）,and OLV 90min（T3）.Platelet（PLT）and mean platelet volume（MPV）were measured at T0,T1,T2,and T3.Record the OLV time,vital signs at each time during the operation,and end-expiratory carbon dioxide(P_ETCO₂)and peak airway pressure（Peak）.Results:There was no significant difference in OLV time between the two groups during operation.During the two HPC sessions,the hypoxia tolerance time was extended from（6.9±1.3）min to（7.9±1.1）min（P<0.05）,no serious adverse reactions were observed.After OLV,the levels of PaO₂ in the two groups were significantly lower than before OLV,but PaO₂ at each time point in the N group was more significantly lower than that in the P group（P<0.05）.After OLV,the Qs/Qt of the two groups was higher than before OLV,but the Qs/Qt of each time point in the N group was more significant higher than that of the P group（P<0.05）.There was no significant difference in PLT and MPV between the two groups（P>0.05）.Conclusion:Hypoxic pretreatment before one-lung ventilation is safe for patients.It can reduce Qs/Qt in patients during OLV,increase PaO₂,and improve the oxygenation of patients undergoing lobectomy.The effect may not be significantly related to platelet count and its function.