The Clinical Observation Of Pretreatment Of Dexmedetomidine On General Anesthesia Surgeries For Young Adults And The Elderly

Objective:Through the observation of the pretreatment of dexmedetomidine on young adults and elderly patients for general anesthesia surgeries, we try to discuss the issues on dosage of propofol, induction and awakening time, hemodynamic and anesthesial side effects.Methods:A total of 80 patients undergoing selective thyroidectomy surgery practicing general anesthesia were divided into 2 groups: young adults group(20~39 years old) and aged patients group(66~80 years old), 40 patients for each age group with ASAⅠ~Ⅱ grade and each age group were randomly divided into two groups: youth DEX group, youth COMP group and aged DEX group, aged COMP group with 20 patients for each group. 10 mins before the general anesthesia, the patients in youth DEX group and aged DEX group received 0.5ug / kg DEX which was diluted to 10 ml over 10 min by pumped infusion before anesthesia induction. Youth DEX group and aged COMP group simply received normal saline in the same way. The ways of anesthesia induction and anesthesia maintenance were same. Plasma concentration of propofol was regulated to maintain depth of anesthesia by inthaoperative BIS value around 45±5. The HR, SBP and DBP of patients were recorded at the point of entering the operative room(T0),before inducing(T1),after inducing(T2),at intubation(T3),cut skin(T4),30 mins after skin cut(T5),after the operation(T6) and at extubation.The propofol’s plasma concentration(Cp) of patients at each point from T2 to T6 were recorded. The propofol’s induction dosage and total dosage,induction time and recovery time were recorded.The pain score, sedation score and vomiting score when 24 hours after surgery were recorded.Results:1.The target-controlled plasma concentration:Comparing within the same age groups,Young COM Group was significantly higher than Young DEX Group, Aged COM Group was significantly higher than Aged DEX Group(P <0.05); Comparing among the different age groups,Aged DEX Group was significantly lower than Young DEX Group(P <0.05),Aged DEX Group, Aged COM Group were significantly lower than Young COM Group(P <0.05).2.Propofol’s induction dosage and total dosage:Comparing within the same age groups, the Propofol’s induction dosage and total dosage of Young COM Group were significantly higher than that of Young DEX Group, Aged COM Group were significantly higher than Aged DEX Group(P <0.05);Comparing among the different age groups,the Propofol’s induction dosage and total dosage of Aged DEX Group were significantly less than that of Young DEX Group,the Propofol’s induction dosage of Aged COM Group was significantly greater than that of Young DEX Group, the total amount of Propofol’s dosage of Aged COM Group was significantly smaller than that of Young DEX Group(P <0.05); The Propofol’s induction dosage and total dosage for Aged DEX Group and Aged COM Group were significantly less than that of the Young COM Group(P <0.05).3.Hemodynamic:Compared at T2 point, the HR、SBP and DBP of Young COM Group and Aged COM Group at T3, T4 and T7 point increased significantly(P <0.05).The HR、SBP and DBP value of Young DEX Group at T7 increased more than that when at T2(P <0.05).4.Induction time: Comparing within the same age groups, the Young COM Group’s induction time was significantly longer than that of the Young DEX Group(P <0.05),the induction time of the Aged COM Group was significantly longer than that of Aged DEX Group(P <0.05);Comparing among the different age groups,Aged COM Group’s induction time was significantly longer than that of the Young DEX Group(P <0.05),Aged DEX Group’s induction time was significantly shorter than that of Young DEX Group(P <0.05); Aged DEX Group induced the shortest, whereas Young COM Group induced the longest. 5.Recovery time: Compared with Young Group, Aged Group were significantly longer(P<0.05).6.The VAS score、Ramesay score、postoperative nausea and vomiting score of the four groups showed no difference when 24 hours after surgery,there was no statistical significance(P>0.05).7.Adverse reaction:the four groups did not appear severe bradycardia,hypotension, chills,postoperative delirium and intraoperative awareness.Conclusion:1.The same dosage of dexmedetomidine has different effects on patients with different ages, when DEX is pretreated for anesthesia for the elderly; the dosage of propofol was significantly less than that of young people.2. Pretreatment of dexmedetomidine can help stable hemodynamic in patients, and the elderly are more stable than the youth.3.The Pretreatment of dexmedetomidine can significantly reduce the anesthesia induction time, and the elderly is shorter than the youth.