Pharmacokinetic Comparison Of Domestic Alfentanil In Teenagers And Young Adults

Objectives To compare the pharmacokinetic characteristics of domestic alfentanil in teenagers and young adults,and analyze the pharmacokinetic significance,so as to provide important reference value for anesthesiologists in the rational application of alfentanil in clinical work.Methods A total of 60 patients with ASAⅠ-Ⅱgrade who underwent selective under general anesthesia were selected,regardless of gender,including 30 teenagers（13-15 years old）and30 young adults（25-45 years old）with BMI<28kg·m^-2.There was no serious concomitant injury,diabetes,pregnancy,lactation,serious heart,liver and kidney dysfunction,and no history of allergy to anesthetic drugs and vasoactive drugs.After entering the room,non-invasive blood pressure,Heart rate,Electrocardiograph,Pulse blood oxygen saturation and bispectral index were monitored.Open upper limb intravenous drip of sodium lactate Ringer injection.The contralateral radial artery catheterization was performed to facilitate blood sampling.Routine anesthesia induction was performed with intravenous injection of midazolam 0.02-0.05mg·kg^-1,etomidate 0.2-0.3 mg·kg^-1,cisatracurium 0.2-0.3mg·kg^-1,and single intravenous injection of alfentanil 50μg·kg^-1 during induction.Three to five minutes later,the trachea was intubated and mechanical ventilation was performed.Sevoflurane 3%-4%and oxygen flow 1-2L·min^-1 were inhaled continuously for anesthesia maintenance in both groups during the operation.The appropriate depth of anesthesia was maintained during the operation（BIS value fluctuated from 40 to 60）.One-third of the induced dose of cisatracurium was given intravenously every half hour,with the last intravenous injection not later than half an hour before the end of surgery.MAP,HR,Sp O₂ and BIS were recorded at five time points 30min before anesthesia induction（T₀）,at induction time（T₁）,at cutaneous incision（T₂）,at the end of surgery（T₃）and 2h after surgery（T₄）.3ml of arterial blood samples were taken at each time point before and 1min,2min,3min,5min,7min,10min,15min,30min,60min,120min,240min and 300min after the injection of alfentanil and placed in one-time vacuum vasopressor after heparinization.The samples were immediately centrifuged for 10min(3000r·min^-1),and 1ml of plasma after precise absorption was placed in a test tube and stored at-80℃for measurement.Liquid chromatography-tandem mass spectrometry（LC-MS/MS）was used to detect the concentration of drug in plasma at different time points.DAS 3.0 software was used for pharmacokinetic parameters analysis,and SPSS 19.0 was used for statistical analysis.Results 1 There was no significant difference in gender,BMI,anesthesia time,operation time and sevoflurane inhalation between the two groups（P>0.05）;2 There were statistically significant differences in age in general information between the two groups （P<0.05）;3 HR in the adolescent group（Group II）was higher than that in the young adult group（Group I）at T₁ and T₂,and the difference was statistically significant（P<0.05）;4 The pharmacokinetic parameters of A、B、α、t_1/2α、β、t_1/2β、CL、K₁₂、K₂₁were not significantly different between the two groups（P>0.05）;5 Vd in the teenagers group（0.4712±0.1725）L·kg^-1 was lower than that in the young adults group（0.6156±0.2701）L·kg^-1,and the difference was statistically significant（P<0.05）;6 K₁₀ in the adolescent group（0.0144±0.0044）min^-1was lower than that in the young adults group（0.0311±0.0116）min^-1,and the difference was statistically significant（P<0.05）.Conclusions 1 It was found that the pharmacokinetics of alfentanil in the two groups were consistent with the open two-compartment model.The pharmacokinetic characteristics of alfentanil in teenagers were not significantly different from those in young adults,suggesting that teenagers should follow the medication principles of adults in the clinical application of alfentanil.2 After intravenous administration of alfentanil,a rapid peak in plasma concentration followed by a rapid decline was observed,which was consistent with the first-order elimination kinetics.Figure 14;Table 6;Reference 128...