1、Obstetric Anesthesia 12Respiratory System:increase in the respiratory minute volume and work of breathingGastrointestinal System:risk of incidence of aspirationendotracheal intubation Renal System:GFR rises 50%;glycosuriaCentral Nervous System:sensitivity to anesthetics.3lO2(Consumption 消耗)+20 to+50
2、%lMV(Minute Ventilation分钟通气量)+50%lTV +40%lPaO2 +10%lPaCO2 -15%lHCO3 -15%lFRC -20%4Placenta 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 li
3、ver.5lNarcotic analgesic morphine pethidine fentanyl alfentanil sufentanil lGeneral anesthetics propofol l吗啡、哌替啶、芬太尼6Placental transfer is rapidMother:uterus reactiveness orthostatic hypotension nausea vomiting delayed gastric emptyingFetus:respiratory depression7Most commonly used during labor intr
4、amuscular dose:50-100 mg Time of IM:before expulsion 1 h or 4 huterine contraction,frequency and intension 8 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%ropivacaine9 Placental transfer No inhibiting uterine c
5、ontraction No Respiratory depression10 Readily cross the placenta Half-lives:48 hours Problems:sedation,hypotonia,cyanosis,impaired metabolic responses to stress.11 Plasma protein binding:94%Respiratory depression:depended on dose 0.075 mg/kg no problem 0.15 mg/kg different degree 12 Pregnant woman:
6、慎用Apgar score 13 Neonatus sleep:little Premature and intrauterine embarrass:carefully using14High 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,
7、gestational hypertension syndrome or preeclampsia,metrorrhexis15 Recommendation:induction:2.5 mg/kg maintenance:2.5-5.0 mg/kg/h Discontinue gravidity only16 Placental transfer is rapid Mothers respiration,circulation and Uterine muscular contraction force 20-30s before of first stage of labor:50%O2
8、and 50%N2O,maximumhalothane19 Cholinesterase:normal doseno placental transfer Dose 300 mg or single dose is larger:still have placental transfer 20Onset is quick,maintanence is short and placental transfer is leastAtracurium:0.3 mg/kg21Factors:lProtein binding:lMolecular weightlLiposolubility lCatab
9、olism in the placent22 Procaine Lidocaine Bupivacaine Ropivacaine23Choice depends on:l the indications for the surgeryl the degree of urgencyl maternal statusl desires of the patient24 Hyperbaric bupivacaine Advantages:rapid onset,little risk of local anesthetic toxicity,minimal transfer to the fetu
10、s,infrequent failure.Disadvantages:finite duration hypotension headache25 L 23 or L 12 1.5%2%Lidocaine or 0.5%Ropivacaine emergency cesarean section26 Increased dramatically in popularity Advantages:rapid onset supplemented at any time anesthetic dose sacral nerves block is sufficient27 rapid induct
11、ion:obviate positive pressure ventilation oppress the cricoid cartilage mainterance:light anesthesia vomiting,backstreaming and aspiration:atropine,0.5 mg,IM or glycopyrolate,0.2 mg,IM28 Incidence:2%30%Time:after 28 weeks,specially 3236 weeks Symptoms:hypotension,dizziness,nausea,chest distress,cold
12、 sweat,to yawn,pulse rate,pallescence29 Emergency operation:late trimester of pregnancy:hemorrhage gestational hypertension syndrom and eclampsia Selective operation:hypertension cardiac disease diabetes multifetation 30 Preanesthtic preparation:blood coagulation function DIC sifting test acute rena
13、l failure Principle:general anesthesia:active bleeding,hypovolemic shock,definite blood coagulation disfunction or DIC intraspinal anesthesia:condition of mother and fetus is okay Management31degrees of abruptio placentae.A,Concealed hemorrhage.B,External hemorrhage.C,Complete placental separation.3
14、2 Types of placenta previa.33 Announcements 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
15、of DIC34 Incidence:10.3%Cause of death:cerebrovascular accident,pneumonedema,liver necrosis Pathophysiology:systemic arteriola systole,fetus Management:37l cardiac failurel cerebral hemorrhagel placental abruptionl blood coagulation disfunctionl haematolysisl hepatic enzymel thrombocytopenial acute
16、renal failure38 trying stable anesthesia:stress reaction:fentanyl avoid to use ketamine SBP:140150 mmHg,DBP:about 90 mmHg ganglioplegic or nitroglycerin maintain heart,kindey and lung function:treatment of complication:39 basic monitoring:ECG SpO2 NIBP CVP urine volume blood gas analysis prepare to
17、salvage the neonatal asphyxia ICU postoperation analgesia40 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
18、syndrome preparation of resuscitation of newborn4142 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)Com
19、pletely pink Reflex irritability(response to insertion of a nasal catheter)Absent Grimace Cough,sneeze Muscle tone Limp Some flexion of extremities Active motion 43 1-minute score -degree of asphyxia 5-minute score-prognosis evaluated at 1 and 5 minutes.should not wait until 1 minute has passed befo
20、re initiating resuscitation.normal:7-10 mild asphyxia:4-6 severe asphyxia:0-3 44l A(Airway)l B(Breathing)l C(Circulation)l D(Drug)l E(Evaluation)45l Incubation:2731l Position:l Suctioning:mouth and nosel Stimulate:Complete it within 20s46l Evaluation:according to breath,heart rate and skin colourl N
21、ormal:stop resuscitation l No spontaneously brathing,HR100/min:bag respiratorl HR80/min:closed cardiac massage;tracheal intubation,medication47 Maniphalanx pressurize Tidal volume:2040ml I:E=1.5:1 RP:3040/min first twice:pressure 3040 cmH2O subsequently:pressure 1020 cmH2O4849HR:120/minDepth:12cm505
22、1 30s after the closed cardiac massage,still cant recovery:drug Epinephrine:0.10.2mg/kg,intratracheal drop in52 umbilical cord was clamped and cut earlier intrauterine asphyxia placental abruption hemorrhage too much:antepartum or intrapartum53 arterial blood pressure and CVP pale skin poor capillar
23、y refill extremities are cold pulses are weak or absent54 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 55Respiratory acidosis is corrected by controlling ventilationMetabolic acidosis is c
24、orrected by infusing sodium bicarbonate.Requisite amount of sodium 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.56l temperaturel breathl heart ratel blood pressurel urine volume57 Special position:head down and lithotomy position Old age:comorbidities Emergency case:exfetation,ovarian cyst intortion,perineal position trauma,uterine perforation More other:selective operation Hysteroscope and Laparoscopic Surgery:58
