产科麻醉英文版.ppt

ObstetricAnesthesiaPhysiologicChangesOfPregnancyCardiovascularSystem:cardiacoutput,heartrateHematologicSystem:bloodvolumeincreasesbyupto45%,redcellvolumeincreasesbyonly30%physiologicanemiaRespiratorySystem:increaseintherespiratoryminutevolumeandworkofbreathingGastrointestinalSystem:riskofincidenceofaspirationendotrachealintubationRenalSystem:GFRrises50%;glycosuriaCentralNervousSystem:sensitivitytoanesthetics.PhysiologicChangesOfPregnancyChangesOfRespiratorySystem lO2(Consumption消耗)+20to+50%lMV(MinuteVentilation分钟通气量)+50%lTV+40%lPaO2+10%lPaCO2-15%lHCO3-15%lFRC-20%Placental Transfer Of Anesthetic Drugs Placenta transport:Simple diffusion Facilitated diffusion Active transport PinocytosisReadily cross:low molecular weights,high lipid solubility,non-ionized Approximately 50%of the umbilical venous blood bypasses the liver.lNarcoticanalgesicmorphinepethidinefentanylalfentanilsufentanillGeneralanestheticspropofoll吗啡、哌替啶、芬太尼Morphine Placental transfer is rapidMother:uterus reactiveness orthostatic hypotension nausea vomiting delayed gastric emptyingFetus:respiratory depressionPethidine Most commonly usedduring labor intramuscular dose:50-100 mgTime of IM:before expulsion 1 h or 4 huterine contraction,frequency and intension Fentanyl Alfentanil Sufentanil Placental transfer is rapid Low dose:10-25 g fentanyl or 5-10 g sufentanil in subarachnoid space PCEA:low dose of fentanyl and 0.1%-0.3%ropivacaineTramadol Placental transfer No inhibiting uterine contraction No Respiratory depressionDiazepam Readily cross the placentaHalf-lives:48 hours Problems:sedation,hypotonia,cyanosis,impaired metabolic responses to stress.MidazolamPlasma protein binding:94%Respiratory depression:depended on dose 0.075 mg/kg no problem 0.15 mg/kg different degree Droperidol Pregnant woman:慎用ApgarscoreThiopentalsodiumNeonatus sleep:little Premature and intrauterine embarrass:carefully usingKetamine High doses(greater than 2 mg/kg)may cause low Apgar scores and abnormalities in neonatal muscle toneLabor pains of uterine contractionUterine muscular tension and contraction forceContraindication:psychosis,gestational hypertension syndrome or preeclampsia,metrorrhexisPropofol Recommendation:induction:2.5 mg/kg maintenance:2.5-5.0 mg/kg/h Discontinue gravidity onlyN2OPlacental transfer is rapid Mothers respiration,circulation and Uterine muscular contraction force 20-30s before of first stage of labor:50%O2 and 50%N2O,maximumhalothaneSuccinylcholine Cholinesterase:normal doseno placental transfer Dose 300 mg or single dose is larger:still have placental transfer Nondepolarizing Muscle Relaxants Onset is quick,maintanence is short and placental transfer is leastAtracurium:0.3 mg/kgLocal anestheticsFactors:Proteinbinding:MolecularweightLiposolubilityCatabolismintheplacentLocal anesthetics Procaine Lidocaine Bupivacaine RopivacaineAnesthesiaForSesareanSection Choicedependson:theindicationsforthesurgerythedegreeofurgencymaternalstatusdesiresofthepatientSpinalAnesthesia Hyperbaric bupivacaine Advantages:rapid onset,little risk of local anesthetic toxicity,minimal transfer to the fetus,infrequent failure.Disadvantages:finite duration hypotension headacheEpiduralAnesthesia L 23 or L 121.5%2%Lidocaineor0.5%Ropivacaine emergency cesarean sectionCombinedSpinal-EpiduralTechnique Increased dramatically in popularity Advantages:rapid onset supplemented at any time anesthetic dosesacral nerves block is sufficientGeneralAnesthesiarapidinduction:obviatepositivepressureventilationoppressthecricoidcartilagemainterance:lightanesthesiavomiting,backstreamingandaspiration:atropine,0.5mg,IMorglycopyrolate,0.2mg,IMSupinehypotensivesyndrome Incidence:2%30%Time:after 28 weeks,specially 3236 weeks Symptoms:hypotension,dizziness,nausea,chest distress,cold sweat,to yawn,pulse rate,pallescenceHigh risk pregnancy Emergency operation:late trimester of pregnancy:hemorrhage gestational hypertension syndrom and eclampsia Selective operation:hypertension cardiac disease diabetes multifetationPlacenta Previa and Placental Abruption Preanesthtic preparation:blood coagulation function DIC sifting test acute renal failure Principle:general anesthesia:active bleeding,hypovolemic shock,definite blood coagulation disfunction or DIC intraspinal anesthesia:condition of mother and fetus is okay Managementdegrees of abruptio placentae.A,Concealed hemorrhage.B,External hemorrhage.C,Complete placental separation.Types of placenta previa.Management of anesthesiaAnnouncements of the induction:difficult airway cricoid cartilage backstreaming and aspiration Prepare to salvage the blood coagulation disfunction and the hemorrhoea.Prevent the acute renal function failure:urine volume urea nitrogen and creatinine Prevention and cure of DICPregnancy-induced hypertension syndromeIncidence:10.3%Cause of death:cerebrovascular accident,pneumonedema,liver necrosis Pathophysiology:systemic arteriola systole,fetusManagement:HELLP syndrome lcardiacfailurelcerebralhemorrhagelplacentalabruptionlbloodcoagulationdisfunctionlhaematolysislhepaticenzymelthrombocytopenialacuterenalfailureManagement 1tryingstableanesthesia:stressreaction:fentanylavoidtouseketamineSBP:140150mmHg,DBP:about90mmHgganglioplegicornitroglycerinmaintainheart,kindeyandlungfunction:treatmentofcomplication:Management 2basicmonitoring:ECGSpO2NIBPCVPurinevolumebloodgasanalysispreparetosalvagetheneonatalasphyxiaICUpostoperationanalgesiaMultiple Births pathophysiology:abdominal aorta and inferior vena cava compression;fetal lung maturity;incidence of postpartum hemorrhage.anesthesia:epidural anesthesia management:addition of volume:colloid oxygen,prevention and cure of Supine hypotensive syndrome preparation of resuscitation of newbornNeonatal asphyxia and emergency treatment ASSESSMENT OF THE FETUS AT BIRTH Apgar score is a simple,useful guide-The Apgar scoring system Score*Sign 0 1 2 Heart rate Absent Less than 100/min More than 100/min Respiratory effort Absent Slow,irregular Good,crying Color Blue,pale Body pink,extre mities blue(acrocyanosis)Completely pink Reflex irritability(response to insertion of a nasal catheter)Absent Grimace Cough,sneeze Muscle tone Limp Some flexion of extremities Active motion Apgar score 1-minute score -degree of asphyxia 5-minute score-prognosis evaluated at 1 and 5 minutes.should not wait until 1 minute has passed before initiating resuscitation.normal:7-10 mild asphyxia:4-6 severe asphyxia:0-3 Resuscitation of newborn lA(Airway)lB(Breathing)lC(Circulation)lD(Drug)lE(Evaluation)Initial resuscitation lIncubation:2731lPosition:lSuctioning:mouthandnoselStimulate:Completeitwithin20sEvaluation and further treatmentlEvaluation:accordingtobreath,heartrateandskincolourlNormal:stopresuscitationlNospontaneouslybrathing,HR100/min:bagrespiratorlHR80/min:closedcardiacmassage;trachealintubation,medicationBag respiratorManiphalanxpressurizeTidalvolume:2040mlI:E=1.5:1RP:3040/minfirsttwice:pressure3040cmH2Osubsequently:pressure1020cmH2ORESUSCITATION EQUIPMENTClosed cardiac massage HR:120/minDepth:12cmRESUSCITATION DRUGS 30s after the closed cardiac massage,still cant recovery:drug Epinephrine:0.10.2mg/kg,intratracheal drop inHypovolemia causes umbilical cord was clamped and cut earlier intrauterine asphyxia placental abruption hemorrhage too much:antepartum or intrapartumDetection of Hypovolemia arterial blood pressure and CVP pale skin poor capillary refill extremities are cold pulses are weak or absentTreatment of Hypovolemia intravascular volume expansion blood,plasma,crystalloid,Albumin 10 mL/kg of normal saline,1 to 2 g/kg of 25%albumin,or 10 mL/kg of plasma.Care must be taken Correction of Acidosis Respiratory acidosis is corrected by controlling ventilationMetabolic acidosis is corrected by infusing sodium bicarbonate.Requisite amount ofsodium bicarbonate(mmol):=0.6BW(kg)(normal BE-present BE)/4 sodium bicarbonate 1 mmol/kg/minSodium bicarbonate should not be infused unless ventilation is adequate.Monitoring After resuscitationltemperaturelbreathlheartratelbloodpressurelurinevolumeGynecologic anesthesiaSpecialposition:headdownandlithotomypositionOldage:comorbiditiesEmergencycase:exfetation,ovariancystintortion,perinealpositiontrauma,uterineperforationMoreother:selectiveoperationHysteroscopeandLaparoscopicSurgery: