產(chǎn)科麻醉英文版

1、Obstetric Anesthesia Department of anesthesiologyCui Xiao Guang,PHYSIOLOGIC CHANGES OF PREGNANCY 1,Cardiovascular System : cardiac output , heart rate Hematologic System : blood volume increases by up to 45% , re

2、d cell volume increases by only 30% --physiologic anemia,Respiratory System : increase in the respiratory minute volume and work of breathingGastrointestinal System : risk of incidence of aspiration↑en

3、dotracheal intubation: the risk Renal System : GFR rises 50% ; glycosuriaCentral Nervous System :↑ sensitivity to anesthetics.,PHYSIOLOGIC CHANGES OF PREGNANCY 2,,PLACENTAL TRANSFER OF ANESTHETIC DRUGS,Placen

4、ta transport : Simple diffusion Facilitated diffusion Active transport PinocytosisReadily cross : low molecular weights, high lipid solubility , non-ionized

5、 Approximately 50% of the umbilical venous blood bypasses the liver.,Morphine,Placental transfer is rapidMother: uterus reactiveness↓ orthostatic hypotension nausea vo

6、miting delayed gastric emptyingFetus: respiratory depression,Pethidine,Most commonly used during labor intramuscular dose : 50 -100 mg Time of IM: before expulsion 1 h or 4 huterine contraction, f

7、requency and intension ↑,Fentanyl Alfentanil Sufentanil,Placental transfer is rapid    Low dose: 10 -25 µg fentanyl or 5-10 µg sufentanil in subarachnoid space PCEA: low dose of fentanyl and 0

8、.1%-0.3% ropivacaine,Tramadol,Placental transfer No inhibiting uterine contraction No Respiratory depression,Diazepam,Readily cross the placenta Half-lives: 48 hours Problems: sedation, hypotonia,

9、 cyanosis, impaired metabolic responses to stress.,Midazolam,Plasma protein binding: 94% Respiratory depression: depended on dose 0.075 mg/kg – no problem 0.15 mg/kg – different deg

10、ree,Chlorderazin,Preeclampsia and eclampsia IM：12.5 – 25 mg Overdose: central inhibition,Promethazine,Prevent emesis Appears in fetal blood within 1 to 2 minutes after intravenous injection in the mother Reaches e

11、quilibrium within 15 minutes,Droperidol,Pregnant woman: 慎用Apgar score ↓,Thiopental sodium,Neonatus sleep: little Premature and intrauterine embarrass: carefully using,Ketamine,High doses (greater than 2 mg/kg) may c

12、ause low Apgar scores and abnormalities in neonatal muscle toneLabor pains of uterine contraction↓Uterine muscular tension and contraction force↑Contraindication: psychosis, gestational hypertension syndrome or p

13、reeclampsia, metrorrhexis,Propofol,Recommendation: induction: <2.5 mg/kg maintenance: 2.5-5.0 mg/kg/h Discontinue gravidity only,N2O,Placental transfer is rapid Mother’s respiration, ci

14、rculation and Uterine muscular contraction force↑ 20-30 s before of first stage of labor: 50% O2 and 50% N2O, maximum<70%,Enflurane and Isoflurane,Light anesthesia: no inhibition Deep anesthesia: mot

15、her: inhibition of uterine contraction, uterine bleeding fetus: disadvantage,Sevoflurane,Placental transfer is more rapid than halothane Inhibition of uterine contraction: >halothane

16、,Succinylcholine,Cholinesterase: normal dose→no placental transfer Dose > 300 mg or single dose is larger: still have placental transfer,Nondepolarizing Muscle Relaxants,Onset is quick, maintanence is short a

17、nd placental transfer is leastAtracurium: 0.3 mg/kg,Local anesthetics,Factors:Protein binding: Molecular weightLiposolubility Catabolism in the placent,Local anesthetics,Procaine Lidocaine Bupivacaine Ropivacai

18、ne,ANESTHESIA FOR CESAREAN SECTION,Choice depends on : the indications for the surgery the degree of urgency maternal status desires of the patient,Spinal Anesthesia,Hyperbaric bupivacaine Advantages : rap

19、id onset, little risk of local anesthetic toxicity, minimal transfer to the fetus, infrequent failure. Disadvantages : finite duration hypotension headache

20、,Epidural Anesthesia,L 2～3 or L 1～2 1.5%～2% Lidocaine or 0.5% Ropivacaine emergency cesarean section,Combined Spinal-Epidural Technique,Increased dramatically in popularity Advantages : rapid onset

21、 supplemented at any time anesthetic dose↓ sacral nerves block is sufficient,General Anesthesia,rapid induction: obviate positive pressure ventilation oppress the cricoid cartil

22、age mainterance: light ansthesia vomiting, backstreaming and aspiration: atropine, 0.5 mg, IM or glycopyrolate, 0.2 mg, IM,Supine hypotensive syndrome,Incidence: 2%～30% Time: after 28 weeks, special

23、ly 32～36 weeks Symptoms: ◆ hypotension, ◆ dizziness, ◆ nausea, ◆ chest distress, ◆ cold sweat, ◆ to yawn, ◆ pulse rate↑, ◆ pallescenceMechanismPrev

24、ent,High risk pregnancy,Emergency operation : late trimester of pregnancy: hemorrhage gestational hypertension syndrom and eclampsia Selective operation : hypertension

25、 cardiac disease diabetes multifetation,Placenta Previa and Placental Abruption,Preanesthtic preparation: blood coagulation function DIC sifting test acute rena

26、l failure Principle: general anesthesia: active bleeding, hypovolemic shock, definite blood coagulation disfunction or DIC intraspinal anesthesia: condition of mother and fetus is okay Management,,degre

27、es of abruptio placentae. A, Concealed hemorrhage. B, External hemorrhage. C, Complete placental separation.,,Types of placenta previa.,Management of anesthesia,Announcements of the induction: difficult airway

28、 cricoid cartilage backstreaming and aspiration Prepare to salvage the blood coagulation disfunction and the hemorrhoea. Prevent the acute renal function failure: urine volume

29、 urea nitrogen and creatinine Prevention and cure of DIC,Pregnancy-induced hypertension syndrome,Incidence: 10.3% Cause of death: cerebrovascular accident, pneumonedema, liver necros

30、is Pathophysiology: systemic arteriola systole, < 200 µm, calcium ion, pachemia, hypovolemia→whole blood and plasma viscosity↑and hyperlipemia→microcirculation perfusion↓→intravascular

31、 coagulation,Pregnancy-induced hypertension syndrome complicating cardiac failure,Digitalization, diuresis, morphine, ↓BP. Anesthesia: epidural anesthesia general anesthesia Management: 毛花苷C -- m

32、aintenance dose: 0.2-0.4 mg furosemide (呋塞米）-- 20-40 mg oxygen maintain stabilization of the respiratory and circulatory system,Severe Pregnancy-induced hypertension syndrome,Preanesthesia prepa

33、re: ★ information of medication ★ magnesium sulfate ★ hypotensive drug ★ liquid intake and output volume Anesthesia: termination of pregnancy epidural anesthesia: no blood coagulation d

34、isfunction, no DIC, no shock and no cataphora general anesthesia: safe of mother > fetus Management:,HELLP syndrome,cardiac failure cerebral hemorrhage placental abruption blood coagulation disfunction

35、haematolysis hepatic enzyme↑ thrombocytopenia acute renal failure,Management 1,trying stable anesthesia: ↓stress reaction: fentanyl avoid to use ketamine SBP: 140～150 mmHg, DBP: about 90 mmHg

36、 ganglioplegic or nitroglycerin maintain heart, kindey and lung function: treatment of complication:,Management 2,basic monitoring: ◆ECG ◆ SpO2 ◆ NIBP ◆ CVP

37、 ◆ urine volume ◆ blood gas analysis prepare to salvage the neonatal asphyxia ICU postoperation analgesia,Multiple Births,pathophysiology: ◆abdominal aorta and inferior vena cava compression;

38、 ◆ fetal lung maturity; ◆ incidence of postpartum hemorrhage. anesthesia: epidural anesthesia management: ◆ addition of volume: colloid ◆ oxygen, prevention and cure of Supine hypotensive syndrome

39、 ◆ preparation of resuscitation of newborn,Neonatal asphyxia and emergency treatment,ASSESSMENT OF THE FETUS AT BIRTH,Apgar score is a simple, useful guide,,,,,,,,,,,,,,,,,,,,,,,,,,,Apgar score,1-minute score --- deg

40、ree 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,R

41、esuscitation of newborn,A ( Airway) B ( Breathing) C (Circulation) D (Drug) E (Evaluation),Initial resuscitation,Incubation: 27～31℃ Position: Suctioning: mouth and nose Stimulate:,,Complete it within 20s,Evaluati

42、on and further treatment,Evaluation: according to breath, heart rate and skin colour Normal: stop resuscitation No spontaneously brathing, HR<100/min: bag respirator HR<80/min: closed cardiac massage; trache

43、al intubation, medication,Bag respirator,Maniphalanx pressurize Tidal volume: 20～40ml I : E = 1.5:1 RP: 30～40/min first twice: pressure – 30～40 cmH2O subsequently: pressure – 10～20 cmH2O,RESUSCITATION EQUIPMENT,C

44、losed cardiac massage,HR: 120/minDepth: 1～2cm,,RESUSCITATION DRUGS,30s after the closed cardiac massage, still can’t recovery : drug Epinephrine: 0.1～0.2mg/kg, intratracheal drop in,Hypovolemia causes,umbi

45、lical cord was clamped and cut earlier intrauterine asphyxia placental abruption hemorrhage too much: antepartum or intrapartum,Detection of Hypovolemia,arterial blood pressure and CVP ↓ pale skin poor capil

46、lary refill extremities are cold pulses are weak or absent,Treatment 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

47、/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 of sodium bicarbonat

48、e(mmol): = [0.6×BW(kg)×(normal BE-present BE)]/4 sodium bicarbonate <1 mmol/kg/minSodium bicarbonate should not be infused －unless ventilation is adequate.,Monitoring After resuscitation,temperature

49、breath heart rate blood pressure urine volume,Gynecologic anesthesia,Special position: head down and lithotomy position Old age: comorbidities Emergency case: exfetation, ovarian cyst intortion, perineal p