The Influence Of Circadian Rhythm On The Anesthetic Dosage Of Elderly Male Patients

Objective:The purpose of this study was to evaluate if circadian rhythm affect thedosage of propofol and remifentanil in elderly male patients under thegeneral anesthesia.Materials and Methods:One hundred elderly male patients undergoing emergency surgery wasslected from June2014to September2014in the first hospital of jilinuniversity. ASA EⅠor E ⅡWithout a history of neurological andpsychiatric diseases and psychiatric history of drug use, alcohol and illicitdrugs, travel across time zones, sleeping disorder. Preoperative andpostoperative liver and kidney function abnormal. Operation time within3to2hours.According to the operation time patients were divided into daygroup(08:00to14:00), night group (19:00to03:00).Preoperative fasting,6h, water deprivation4h, without giving any sedation, analgesic drugs.Cleaning the patient’s forehead with75%alcohol, paste electrodes, testeach electrode resistance less than8k Ω, start Nareotrend monitoring.Oxygen inhalation with mask5L/min, Anesthesia was induced with,fentanyl3μ g/kg, cisatracurium0.15mg/kg, propofol2mg/kg.mechanical ventilation. Anesthesia was maintained with continuous infusion of propofol5mg/kg.h and remifentanil1μg/kg.h. Musclerelaxant is given at appropriate time.In according to the NTI toadjustment the infusion speed of propofol.maintain NTI between46to37.according to the hemodynamic changes to adjust the speed offentanyl,maintain blood pressure and heart rate fluctuations in basic valuerange30%. Intraoperative if HR less than50times/min,0.3mg atropinewas given. At the end of the operation, stop the infusion of propofol andfentanyl. Pressure(MAP) heart rate(HR) and NTI were recorded at thetime of before induction of anesthesia (T0), immediately after intubation(T1), operation starting (T2), the end of operation (T3), and the totaldosage of propofol and fentanyl.Results:All patients were successfully complete the study, no adverse eventsoccurred during operation. There were no significant difference betweentwo groups in operation time MAP HR and NTI.But in the night group,the total dosage of propofol was3.6±0.9mg/kg.h and remifentanil was9.4±0.7ug/kg.h,significantly less than the day group.Conclusion:The circadian rhythm has some influence on anesthetic dosage in theelderly male patients undergoing general anesthesia,it can save anestheticduring night.