倫敦帝國大學 馬大青博士 右美托咪定

1ClinicalApplicationsofDexmedetomidine:

Frombenchtobedside

Dr.DaqingMaMD,PhDAnaesthetics,PainMedicine&IntensiveCareDepartmentofSurgery&CancerImperialCollegeLondonMagillAnaesthesiadepartmentChelseaandWestminsterHospitalAnnualmeetingofChineseSocietyofAnesthesiology-Sept24,2010Beijing

新晨衛(wèi)星會OutlineIntroduction LaboratorybenchworkBedside:clinicalapplications(sedation;painrelief;anaesthesia)Conclusions Alpha-2adrenoceptoragonist–HistoryOlddrugforveterinaryanaesthesiasince1967.Centralalpha-2receptorbeingestablishedat1981.

Xylazine+Ketamineforrodents…Cattle

AnxiolysisAnalgesiaSedationAnaestheticsparingCytoprotection

Clonidine

2:1=200:1>10min9-12hrs20%1.7-2.5L/kgLiver50%Kidney30%Faeces20%Dexmedetomidine

2:1=1600:1>5min2hrs94%200L?????ClClNNHNHNNHCCH3HCH3H3CAlpha-2adrenoceptoragonist-PharmacokineticsSelectivityt1/2

t1/2

BindingtoalbuminVolumedistributionMetabolisedAlpha-2adrenoceptoragonist-PharmacodynamicsCa++Ca++Ca++––+Decreasein

influxofCa++Decreaseinaction

potentialdueto

hyperpolarization

2A

2ARGoGkK+K+K+Alpha-2adrenoceptoragonist-PharmacodynamicsHypotensionBradycardiaImidazolinereceptoragonist–DexTwosubtypesofimidazolinereceptorI1andI2I1receptors:restricteddistributionintheventrolateralmedulaI2receptors:Brain,kidneyandpancreas,functionnotclearDexmedetomidine:SedationDexmedetomidinevssedationorsleepThesleepswitch:hypothalamiccontrolofsleepandwakefulness(Saperetal,2001)DexmedetomidinevssedationorsleepDEXinducedaqualitativelysimilarpatternofc-Fos(aneuronalactivationmarker)expressioninratsasseenduringnormalNREMsleep:i.e.AdecreaseintheLCandTMNAnincreaseintheVLPO.(Nelsonetal,Anesthesiology2003)DexmedetomidinevsCytoprotection(Qiaoetal.CriticalCare2009)DexmedetomidinevsCytoprotection(Qiaoetal.CriticalCare2009)OutcomesinMVpatientssedatedwithDexmedetomidineDoseused:Dex1.5μg/kg/hr<120hrs.OutcomesinMVpatientssedatedwithDexmedetomidineSepsisvsnoSepsisEfficacyoutcomesinpatientstreatedwithDexvsMidazolamDoseused:Dex0.2-1.4μg/kg/hruntilextubationor30days.LongtermsedationwithDex–acasereportBoysufferedlivercirrhosisHadlivertransplantationattheageof9monthsLong-termMVSedatedwithmidazolam(1.7mg/kg/hr)andFentanyl(3.5μg/kg/hr)-inadequate.Onpostopertiveday29,Dexwasadded(1.4μg/kg/hr).SupplementwithmidazolamorketamineWasextubated10weeksafteroperationConclusion:Dexwasusedfor2weekswithnosignsofwithdrawaleffects.DexcanbeusedforsedationforaninfantwhoreuiredMVforaprolongedperiodoftime.Dexmedetomidine:AnalgesiaDexmedetomidinevsAnalgesiaSalineDex1μgDex3.