Correlative Study On The Relationship Between Gender Difference And The Dosage Of General Anesthetics In The Elderly

Objective:This study explores whether there is gender difference for the elderly in the dosage of etomidate for induction of general anesthesia and propofol for maintenance of anesthesia,provides a reference for the precise and appropriate anesthesia for elderly patients,ensures the safety of general anesthesia for the elderly and facilitates early postoperative rehabilitation.Methods:99 patients who were scheduled to undergo elective surgery under general anesthesia from September 2018 to December 2019 in the Second Hospital of Jilin University were randomly selected with the standard of ASA II-III grade,40-90 kg weight and 65-85 years of age.Two groups were divided according to the gender:the elderly male group(M group,46 cases)and the elderly female group(F group,53 cases).All patients were fasted before the operation,opened the intravenous access of upper limb after entering the operating room and given 1 mg penehyclidine hydrochloride.Non-invasive blood pressure,electrocardiogram and blood oxygen saturation were monitored routinely,and invasive blood pressure was also monitored at the same time.Moreover,the bispectral index monitor is connected to monitor the depth of anesthesia.All patients of both two groups were given rapid induction of total intravenous anesthesia: midazolam 0.05 mg/kg,fentanyl 4 μg/kg,cis atracurium benzenesulfonate 0.15 mg/kg,and finally,the etomidate was injected at a constant speed of 1 ml/s.The injection was stopped when the BIS value was lower than 60,and the dosage of etomidate was recorded.Propofol and remifentanil were infused intravenously to maintain the depth of anesthesia of all patients in both groups.Fentanyl citrate 2 μg/kg and cis atracurium benzenesulfonate 0.05 mg/kg were added at the beginning of the operation,then cis atracurium 0.05 mg/kg was added every 40 minutes and fentanyl citrate 2 μg/kg was added every 1 hour.It was expected to stop adding the muscle relaxants 1 hour before the end of operation.The initial infusion speed of propofol and remifentanil was 5 mg/(kg·h)and 15 μg/(kg·h),respectively,and then the dosage was adjusted according to the BIS value to maintain its value between 40 and 60.At the end of the operation,the infusion of anesthetics was stopped immediately.After the patient regained consciousness and spontaneous breathing,the endotracheal tube was removed and the patient was sent to the post anesthesia care unit.The following indexes of patients in both two groups were recorded:(1)the height,weight,age,ASA grade,operation time,anesthesia time,operation type and other general information of patients in both two groups;(2)the number of patients with hypertension,diabetes,heart disease and cerebrovascular disease before operation;(3)the mean arterial pressure,heart rate,BIS value and blood oxygen saturation of patients in both two groups at the time of entering operating room(T0),before induction(T1),intubation(T2),the beginning of operation(T3),the end of operation(T4)and extubation(T5);(4)the intraoperative application of vasoactive drugs of patients in both two groups;(5)the intraoperative infusion volume and urine volume of patients in both two groups;(6)postoperative follow-up of patients with intraoperative awareness and delirium;and(7)the dosage of etomidate during general anesthesia induction of patients in both two groups,maintenance dosage of propofol(B),maintenance dosage of fentanyl citrate(F),maintenance dosage of remifentanil(R),and maintenance dosage of cis atracurium benzenesulfonate(H).Results:1.There was no statistically significant difference in age,ASA grade,operation type,operation time and anesthesia time for patients between two groups(P > 0.05),but there were statistically significant differences in height and weight(P < 0.01);2.There was no statistically significant difference in the proportion of patients with hypertension,diabetes,heart disease,cerebrovascular disease,and other special conditions for patients between two groups(P > 0.05);3.There were relatively statistically significant difference in:(1)the mean arterial pressure at the time of T2(intubation),T3(at the beginning of operation),T4(at the end of operation)and T5(extubation);and(2)the heart rate at the time of T1(before induction)and T3(at the beginning of operation)for patients between two groups(P < 0.05).There was no statistically significant difference in the MAP and the HR for patients in both two groups at any other point of time(P > 0.05),and there was no statistically significant difference in the blood oxygen saturation and the BIS value at each point of time(P > 0.05);4.There was no statistically significant difference in the intraoperative application of vasoactive drugs for patients in both two groups(P > 0.05);5.There was no statistically significant difference in intraoperative fusion volume and urine volume for patients between two groups(P > 0.05);6.There was no intraoperative awareness and postoperative delirium for patients in both two groups(P > 0.05);7.There was no statistically significant difference in the dosage of etomidate during general anesthesia induction,maintenance dosage of propofol(B),maintenance dosage of fentanyl citrate(F),maintenance dosage of remifentanil(R),and maintenance dosage of cis atracurium benzenesulfonate(H)for patients between two groups(P > 0.05).Conclusions:There was no statistically significant difference in the dosage of etomidate per kilogram used for the induction of anesthesia between elderly male patients and elderly female patients.There was no statistically significant difference in the dosage of propofol per kilogram hour for the maintenance of anesthesia between elderly male patients and elderly female patients,but the dosage of etomidate for induction and propofol for maintenance of anesthesia in both of two groups were lower than the minimum dosage recommended in the operation instruction.It can be concluded that the gender difference can be ignored while using etomidate for induction and propofol for maintenance during clinical anesthesia for the elderly,which is significantly different from previous research results that the dosage of propofol for female patients is significantly larger than that for male patients.