Anesthesia for Cesarean Section Emergent CS General Anesthesia

Anesthesia for Cesarean Section -Emergent C/S & General Anesthesia Department of Anesthesiology, NTUH R 3 Chang-Fu Su

Cesarean Section • C/S rate 14 -15% at US (20 -25% at Taiwan) • Anesthesia: 3 -12% maternal death – Majority during G/A: failed intubation, ventilation, oxygenation and pulmonary aspiration of gastric content – Risk factor: obesity, hypertensive disorder of pregnancy, emergently performed procedure.

Indication for Cesarean Section-1 • Repeat cesarean section – Scheduled – Failed attempt at vaginal delivery • Dystocia • Abnormal presentation – Transverse lie – Breech presentation – Multiple gestation

Indication for Cesarean Section-2 • Fetal stress/distress • Deteriorating maternal medical illness – Preeclampsia – Heart disease – Pulmonary disease • Hemorrhage – Placenta previa – Placenta abruption

Preparation of Anesthesia • Preanesthetic medication – Sedative drug(x), atropine (x, not routine) • Intravenous fluids – 15 -20 ml/kg L/R or N/S within 30 min – In urgent situation, not necessary to wait – Keep BP , improve uteroplacental perfusion • Maternal position (avoid aortocaval compression , left uterine displacement) • Monitoring

Anesthetic technique • Spinal anesthesia – For most elective and urgent C/S • Epidural anesthesia – Decrease likelihood of hypotension • Combined Spinal-Epidural anesthesia • General anesthesia

Epidural anesthesia • Advantage – Titration (volume dependent, not gravity dependent), decreased likelihood of hypotension – Incremental dose (for longer operation) • Disadvantage – Dural puncture : 1/200 -1/500 in experienced hands, higher in training institution – If unintentional dural puncture, PDPH incidence is 5085% – Slower onset

General anesthesia • Regional anesthesia is best in most C/S • Avoid GA in difficult intubation, hx of malignant hyperthermia, severe asthma • Risk of maternal aspiration and neonatal depression

General anesthesia for C/S Method (1) • Left uterine displacement, monitor, preoxygenation , wait for operator preparation • Cricoid pressure (rapid sequence induction) • Induction: ketamine(1. 0 mg/kg) or thiopental (4 mg/kg) and SCC(1. 0 -1. 5 mg/kg) or (rocuronium) • Intubation with a smaller ET tube • 30%-50% N 2 O in O 2 and low concentration volatile inhalation anesthetic

General anesthesia for C/S Method (2) After delivery • Increase N 2 O with or without low concentration volatile inhalation anesthetic • Opioid • Intravenous hypnotic agent (benzodiazepine, barbiturate, propofol) if needed • Muscle relaxant • Extubation awake with intact airway reflex

Emergency Cesarean Section(1)Stable • Chronic uteroplacental insufficiency • Abnormal fetal presentation with ruptured membrane (not in labor) • ==>Preferred anesthetic technique : Epidural, spinal

Emergency Cesarean Section(2)Urgent • • • Dystocia Failed trial of forceps Active genital herpes infection with ROM Previous classical C/S and active labor Cord prolapse without fetal distress Variable deceleration with prompt recovery and normal FHR variability • Extension of preexisting epidural anesthesia or Spinal

Emergency cesarean section(3)Stat • • Massive maternal hemorrhage Ruptured uterus Cord prolapse with fetal bradycardia Agonal fetal distress (e. q. , prolonged bradycardia or late deceleration with no FHR variability) • General unless preexisting epidural anesthesia can be extend satisfactorily

Other indication for GA for C/S? • Severe pre-eclampsia (hypertension, proteinuria) – HELLP (Hemolysis, Elevated Liver Enzyme, and Low Platelets) • Eclampsia • Contraindication for regional anesthesia ( patient deny, local infection, bleeding tendency, local infection over injection area, allergy to local anesthetic)

Discussion • Does low concentration volatile halogenated agent or non-depolarizing muscle relaxant depress uterine contraction? • Does Opioid accumulate in breast milk? (45 min, 10 hr) • Is our GA patient under enough anesthesia?

Thanks for your attention!