Effect of thoracic epidural anesthesia with bupivacaine on arterial oxygenation during one-lung ventilation

JIANG Daming; WANG Lijun; GU Lianbing

Abstract：Objective To study the effects of thoracic epidural anesthesia(TEA) with bupivacaine on oxygenation, shunt fraction during one-lung ventilation( OLV) . Methods Sixty patients who had prolonged periods of OLV for elective thoracic surgery for esophageal cancer were randomized into two groups. Thirty patients ( group A) were anesthetized with propofol/atracurium/epidural thoracic bupivacaine 0?5%. In another 30 patients ( group B) , fentanyl/propofol/atracurium anesthesia was used. A double-lumen en-dotracheal tube was inserted, and mechanical ventilation with 100% oxygen was used during the entire study. Arterial and venous blood gases were recorded before surgery in a lateral position with two-lung ventilation, 15 and 30 min after OLV ( OLV+15 and OLV+30, respectively) in all patients. PaO2, venous central oxygen tension, arterial and central venous oxygen saturation, venous admixture per-centage (Qs/Qt) were measured. Results The mean values for PaO2 during OLV in the group A after 15min with (219?3±48?2)mm-Hg and 30min with ( 174?7 ± 37?6 ) mmHg were significantly lower compared with the group B ( 268?1 ± 81?2mmHg and 221?6 ± 87?0mmHg, respectively) . Furthermore, Qs/Qt was significantly increased in group A during OLV. And, blood pressure was signifi-cantly lower in group A during surgery. There were no significant differences. Conclusion We conclude that using the TEA regimen is associated with a lower PaO2 and a larger intrapulmonary shunt during OLV than with total anesthesia alone.