Analgesia requirements of different anaesthesia application methods on thoracotomy cases and evaluation of postoperative cognitive function

Faster recovery from general anaesthesia and improve better mental functions is one of the important aims of anaesthesiologists.40 patients in status ASA I-III, 18-80 years of age undergoing elective lung surgery were randomly divided into two groups. Group I: General anaesthesia (maintenance; Isoflurane+ 50% O2 +air) +Thoracic Epidural Analgesia (bupivacaine) Group II: General anaesthesia (maintenance; Total Intravenous Anaesthesia, propofol+ 50% O2 + air)+ Thoracic Epidural Analgesia (bupivacaine). A thoracal epidural catheter was inserted into all patients preoperatively. Peroperative hemodynamic changes, analgesia requirements, arterial blood gases measurements were recorded. Postoperative hemodynamic changes were recorded and to evaluate cognitive function, the Short Orientation Memory Concentration Test (SOMCT) administered to all patients.Depth of anaesthesia was adjusted to keep a bispectral indeks of between 40 and 60 in both of the groups. There were no significant differences on hemodynamic changes between the groups. The peroperative analgesia requirement of propofol group was lower. 30 minutes after the one-lung ventilation; arterial blood measurements of PO2 values were decreased in both of the groups.In our trial we suggested that different anaesthesia application methods; inhalation or TIVA are both effective for hemodynamic control in thorocotomy surgeries. 15 minutes after the extubation the SOMCT scores of patients was significantly higher in isoflurane group than propofol group. There were no significant differences of SOMCT scores between the groups 3 hours after the extubation. But we concluded that assessment of cognitive function trials requires even larger group of patients.Key Words: Isoflurane, TIVA, One-lung Ventilation, Cognitive Function