急诊剖宫产的 麻醉选择和术中处理,费敏 2010-3-26,Definition,Abdominal delivery a surgical procedure that permits delivery of the infant through incisions in the abdominal and uterine wall.,Cesarean Section,Caedere Seco Pompilius II 730 BC not widely used until the 1920s,Indications for Cesarean Section,Repeat Scheduled Failed attempt at vaginal delivery Dystocia Abnormal presentation Transverse lie Breech Multiple gestation,Fetal stress/distress Deteriorating maternal medical illness Preeclampsia Heart disease Pulmonary disease Hemorrhage Placenta previa Placental abruption,Cesarean Section,60% unplanned More extensive peripartum monitoring Lower threshold for surgical intervention,What is an emergency Caesarean section? -Category 1 & 2,Category 1 Indication,Placental abruption uterine rupture cord prolapse Actively bleeding placenta praevia Intrapartum hemorrhage Presumed fetal compromise with severely abnormal CTG and/or severe fetal acidosis,The 30-minute rule,a maximum decision-to-delivery time of 30 min for Category 1 situation Association of Anaesthetists of Great Britain and Ireland and ObstetricAnaesthesists Association. Guidelines for obstetric anaesthesia services; 2005. Hillemanns P, Strauss A, Hasbargen U, et al. Crash emergency cesarean section: decision-to-delivery interval under 30 min and its effect on Apgar and umbilical artery pH. Arch Gynecol Obstet 2005; 273:161165. anaesthetist informed delivery,Perianesthetic Evaluation,A directed history and physical examination platelet count An intrapartum blood type and screen for all parturients reduces maternal complications Perianesthetic recording of the fetal heart rate reduces fetal and neonatal complications,A directed history and physical examination,Maternal health and anesthetic history Relevant obstetric history Airway and heart and lung examination Baseline blood pressure Back examination when neuraxial anesthesia is planned or placed,Platelet count,A routine intrapartum platelet count does not reduce maternal anesthetic complications Suspected preeclampsia or coagulopathy Eclamptic - plt 80*109 .l-1 Moodley J, Jjuuko G, Rout C. Epidural compared with general anaesthesia for Caesarean delivery in conscious women with eclampsia. British Journal of Obstetrics and Gynaecology 2001; 108: 37882.,Aspiration Prophylaxis,clear liquids up to 2h before induction of anesthesia A fasting period for solids 68 h(fat content?) Further restriction morbid obesity, diabetes, difficult airway nonreassuring fetal heart rate pattern Antacids, H2 Receptor Antagonists, and Metoclopramide reduces maternal complications,Perianesthetic Maternal Position,Aortocaval compression 3 mechanisms uteroplacental perfusion venous return C.O. and BP Obstruction of uterine venous drainage uterine venous pressure and uterine artery perfusion pressure Compression of aorta or common iliac arteries uterine artery perfusion pressure,Perianesthetic Maternal Position,Avoid aortocaval compression Kinsella SM. Editorial. Lateral tilt for pregnant women: why 15 degrees? Anaesthesia 2003; 58: 8357.,Choices of Anesthesia,General anesthesia Regional anesthesia Local anesthesia,Choices of Anesthesia,depends on the indications for the surgery the degree of urgency maternal and fetus status desires of the patient Safest + most expedient,midwife,anesthetist,obstetrician,Regional anesthesia,85% emergency Caesarean section 3% Regional anesthesia require conversion to GA,Regional anesthesia,Epidural anesthesia spinal anesthesia Combined Spinal/Epidural (CSE),Epidural ,As fast as GA Titrated dosing and slower onset risk of severe hypotension and reduced uteroplacental perfusion Duration of surgery not an issue Less intense motor blockade Lower extremity “muscle pump” may remain intact incidence of thromboembolic disease,Epidural ,Risk of systemic local toxicity Greater placental transfer of drug than with spinal BUT does not affect neonatal Apgar score and of little clinical significance when appropriate doses used Risk of high spinal,Epidural,The speed of onset The choice of local anesthetic Possible adjuvants,Epidural,0.5% bupivacaine 0.75% ropivacaine 0.5% levobupivacaine 2-chloroprocaine lidocaine 1.8% lidocaine, 0.76% bicarbonate and 1 : 200 000 epinephrine Allam J. Anaesthesia 2008; 63:243249.,Epidural failure,24% fail to achieve a pain-free operation Kinsella SM. A prospective audit of regional anaesthesia failure in 5080 caesarean sections. Anaesthesia 2008; 63:822832. Conversion to Spinal anesthesia? unpredictable high-spinal blocks a relative contraindication to give spinal anaesthesia following epidural analgesia in labour the dose of local anesthesia by 2030% and use addition of opioids a normal dose of local anesthesia after 30 min since the last dose of epidural with no documented block,Spinal ,Simple Rapid onset Dense blockade Negligible maternal risk of systemic local toxicity Minimal transfer of drug to infant Negligible risk of local anest