Cardiac Arrest in the Obstetric Suite

1. Cardiac Arrest in the Obstetric Suite

2. Case Summary: 1 A 40 year old woman, 37 weeks pregnant with TWINS arrives at the hospital Cervix: 6 cm dilated. Patient is in severe pain. Labor is progressing rapidly Epidural block: 15 ml 0.125% bupivacaine + fentanyl 75 �g 15 minutes later - patient is still in severe pain 12 ml 0.25% bupivacaine given in two increments Patient is comfortable. You go to bed and fall into a deep sleep�...

3. Case Summary: 2 Obstetrician and anesthesiologist called �stat� to labor room Membranes ruptured spontaneously 10 min ago 3 min ago, the patient complained of difficulty breathing and lost consciousness Fetal heart rate: 90 beats/min Vaginal bleeding Patient cyanotic Maternal BP and Pulse not obtainable

4. Case Summary: 3 Patient mask ventilated with Ambu bag and O2 No improvement� Cardiac arrest team called �stat� You start CPR with the aid of the nurse Code team arrives - starts Advanced Cardiac Life Support (ACLS) Patient is intubated - she aspirates gastric contents! ASYSTOLE diagnosed

5. Case Summary: 4

6. Case Summary: 5 Delivery of male infants: A: Apgar: 0, 1, 4 (at 1, 5, and 10 minutes) B: Apgar: 0, 0, 0

7. Case Summary: 6 Maternal heart rate returns BP 100/70; Pulse 130 Significant bleeding

8. Possible Causes of Cardiac Arrest Amniotic fluid embolism Pulmonary embolism Hemorrhage (including ruptured uterus) Myocardial infarction, cardiomyopathy High spinal (or sub-dural) anesthesia Spinal opioid respiratory depression Drug overdose or toxicity

9. �Let�s Do an Elective C/Section�� Healthy 30 y old primigravida with twins for elective C/S (breech/Vx) 5 ft 4 inches tall, 70 kg Patient is active: runs 5 miles x 3 each week Pre-operative: BP = 98/60; Pulse 52 Fluid preload - 1500 ml crystalloid solution Uncomplicated spinal at L3/4, patient sitting Bupivacaine 12 mg + Fentanyl 10 �g + Morphine 0.2 mg

10. Continued: Patient is placed supine, left uterine displacement Block T4 bilaterally (3 min after spinal) �I don�t feel well� My hands are numb� �I can�t breathe.� Poor hand strength - patient cannot raise arm Patient is anxious, diaphoretic, nauseated

11. Events after Spinal Block for Cesarean Section

12. Cardiac Arrest during Spinal for Cesarean Section Code team called; trachea intubated CPR / ACLS started Immediate Cesarean Section performed Delivery: 5 min after arrest occurred Apgar scores: A: 5, 6, 7 B: 3, 4, 5 Babies to Intensive Care; severely acidotic

13. Post-Delivery Course Mother responds to epinephrine: 1 mg x 3 after 10 minutes of resuscitation (5 min after delivery) BP 160/110, P 140 To ICU, intubated Mother has residual neurologic deficit; memory and concentration significantly impaired Unable to work or care for babies Babies appear normal at 2 years of age

14. Possible Outcomes Mother and babies die or brain-damaged Mother and babies intact Mother intact, babies die or impaired Mother brain damaged, babies intact Family takes legal action against hospital, anesthesiologist, obstetrician

15. Cardiac Arrest in Pregnancy Maternal diagnosis Fetal condition and maturity How rapidly and appropriately medical and nursing personnel respond Resources available in hospital

16. Cardiac Arrest in Pregnancy Maternal diagnosis Fetal condition and maturity How rapidly and appropriately medical and nursing personnel respond Resources available in hospital

20. Cardiac Arrest in Pregnancy:Complicated by Physiologic Changes Rapid development of hypoxia, hypercapnia, acidosis Risk of pulmonary aspiration Difficult intubation AORTO-CAVAL COMPRESSION by pregnant uterus when mother supine Changes greater in multiple pregnancy, obesity

23. Cardiac Arrest in Pregnancy:Special Problems Cardiac output during closed chest massage in CPR only ~ 30% normal Cardiac output in the supine pregnant woman is decreased 30-50% due to aortocaval compression Combined effect of above: There may be NO cardiac output!

24. Important Questions How should we perform Emergency Cardiac Care (CPR and ACLS) in the pregnant patient? Should we do anything differently?

25. Guidelines 2000 for Cardiopulmonary Resuscitation and Emergency Cardiac Care Anticipatory treatment of cardiac arrest Emphasis on Automatic External Defibrillators (AEDs) Competent bag-mask ventilation - may be better than intubation attempts Use of amiodarone 300 mg IV (in place of lidocaine*) Vasopressin 40 mg x 1 (alternative to repeated doses epinephrine 1 mg IV every 3-5 min*) Family presence during resuscitation

26. Cardiac Arrest in Pregnancy Anticipatory treatment: Lateral or tilt position 100% oxygen IV fluid bolus Evaluate all drug therapy Basic Life Support: Uterine displacement (manual, hip wedge, etc.) Compress higher on sternum than usual Advanced Cardiac Life Support

27. Cardiopulmonary Resuscitation in Pregnancy LEFT UTERINE DISPLACEMENT - how? EARLY ENDOTRACHEAL INTUBATION START CESAREAN SECTION BY 4 MIN (if > 20 weeks): helps both mother and fetus EARLY OPEN CHEST MASSAGE (~ 15 min) Consider cardiopulmonary bypass: Amniotic fluid embolus, drug toxicity

30. Cardiopulmonary Resuscitation in Pregnancy LEFT UTERINE DISPLACEMENT - MANUAL EARLY ENDOTRACHEAL INTUBATION START CESAREAN SECTION BY 4 MIN (if > 20 weeks): helps both mother and fetus EARLY OPEN CHEST MASSAGE (~ 15 min) Consider cardiopulmonary bypass: Amniotic fluid embolus, drug toxicity

31. Resuscitation Drugs in Pregnancy Epinephrine, amiodarone, vasopressin, norepinephrine, dopamine as clinically indicated Epinephrine, atropine, lidocaine via trachea at 2 to 2.5 times usual IV dose if no central access Greater acidosis and aortocaval compression may necessitate larger doses of bicarbonate

32. Why is Urgent Delivery Indicated? Maternal brain damage may start at ~ 4-6 min What is good for mother is usually good for baby Most intact newborns delivered within 5 min Closed chest massage is less effective with time CPR may be totally ineffective before delivery: Many reports of mother �coming back to life� after delivery

33. Cardiac Arrest in Pregnancy: Older Approach < 24 weeks: Fetus non-viable - try not to deliver Mother is the only consideration > 24 weeks: Consider both mother and fetus Mother is 1st priority Monitor fetal well-being Try to avoid delivery before 32 weeks

34. Cardiac Arrest in Pregnancy: Current Approach < 20 weeks uterine size: Aortocaval compression not significant Delivery may not help > 20-24 weeks uterine size: Aortocaval compression significant (no venous return at low perfusion pressures) Start Cesarean Section by 4 minutes Delivery by 5 minutes

35. Advantages of Early Delivery Aortocaval compression relieved: Venous return ?, Cardiac output ? Ventilation improved: Functional Residual Capacity ? Oxygenation improved Oxygen consumption ?, CO2 production ? Improved maternal and newborn survival

39. �Perimortem� Cesarean Section Start by 4 minutes, deliver by 5 minutes May help even if performed later Have �stat� C/S kit available Perform operation in patient�s room: Can move to OR after delivery Don�t worry about sterility Vertical abdominal incision quickest Prepare for uterine hypotonia and bleeding

40. Optimal Outcome

41. Optimal Outcome

44. Common Problems in Obstetrics Denial of problem ? delay in response Communication errors Obstetric staff not prepared for catastrophes Inadequate response from transfusion or labs Back-up help cannot find the Obstetric Suite! No specialty in-house surgeons (e.g., for airway, vascular, cardiac problems) No ICU facilities

45. Preparation for Obstetric Emergencies Essential equipment immediately available Help for anesthesiologists, surgeons, nurses Written protocols for common emergencies Procedures for urgent lab tests (including coagulation tests) and reporting of results Mandatory training in CPR and ACLS for pregnant patients for all personnel Emergency drills / simulator training

46. �CODE OB� Operator receives call - initiates �Code OB� Team includes: Usual �Code Blue� team Obstetrician (in-house) Obstetric anesthesiologist Newborn resuscitation team and equipment Surgical nurse with emergency Cesarean tray Start CPR & ACLS and prepare for C/S

47. What is Essential Equipment? Pulse oximeter Cardiac arrest cart; defibrillator Automatic Electric Defibrillator (AED)? Cesarean section instruments Difficult intubation equipment (including LMA, jet ventilator, fiberoptic laryngoscope) Thoracotomy instruments Blood warmer and rapid fluid infuser Central venous and arterial line equipment Malignant hyperthermia kit

51. High Incidence of Cardiac Arrest Following Spinal Anesthesia Incidence as high as 1:1000 - 1:1600 surgical cases Death or brain damage in 90% patients Vagal predominance important contributor Treatment should include: Strong vagolytic agent (atropine) Alpha- or mixed agonists (phenylephrine, epinephrine) Fluids (colloids, crystalloid)

52. Management of High Spinal in Pregnancy Evaluate severity and progression of symptoms Left uterine displacement DO NOT elevate patient�s head - ? cerebral perfusion 100% O2 by mask: Cricoid pressure, mask ventilation Intubate (thiopental, succinylcholine only if patient awake) Rapid infusion of crystalloid, colloids Bradycardia: treat with atropine Pressors: Ephedrine, Phenylephrine, Epinephrine

53. Cardiac Arrest During Regional Block High sympathetic block Cardio-accelerators (T1 - 4) blocked Complete vasodilation ? No venous return Vagal predominance Vasopressin may be better than epinephrine: Vasoconstrictor at high doses Transfers blood from peripheral to central compartment Prolonged action of single dose (10-20 min 1/2 life) Fewer adverse effects than epinephrine

54. Epinephrine vs. Vasopressin for Resuscitation during Epidural Anesthesia (in pigs)Coronary Perfusion Pressure after Epidural Saline

55. Epinephrine vs. Vasopressin for Resuscitation during Epidural Anesthesia (in pigs)Coronary Perfusion Pressure after Epidural Bupivacaine

56. The Efficacy of Epinephrine and Vasopressin for Resuscitation during Epidural Anesthesia (in pigs) Vasopressin lasted longer than epinephrine Greater acidosis with epinephrine Post-resuscitation, more hypertension and tachycardia after epinephrine Trend to better survival with vasopressin Bradycardia requiring atropine more frequent after vasopressin �Vasopressin may be a more desirable vasopressor for resuscitation during epidural blockade��

57. The Cesarean Delivery Decision - Not an Easy One! Has 3-4 min passed since cardiac arrest? Has the mother responded to resuscitation? Was resuscitation optimal - can it be improved? Is an immediately treatable condition (e.g, seizures) present? If so, C/S may not be necessary

58. The Cesarean Delivery Decision - Not an Easy One! Has the mother suffered an inevitably fatal injury? Has so much time passed that maternal survival with good outcome is impossible? In most cases in late pregnancy, immediate delivery benefits mother and/or baby

59. Summary Cardiac arrest is the final common pathway for many conditions Maternal and fetal survival depend on rapid and skilled resuscitation Consider early (< 5 min) Cesarean delivery Training in ACLS for pregnant woman essential for maternity unit personnel Be prepared!!

60. Summary Cardiac arrest is the final common pathway for many conditions Maternal and fetal survival depend on rapid and skilled resuscitation Consider early (< 5 min) Cesarean delivery Training in ACLS for pregnant woman essential for maternity unit personnel Be prepared!!

61. Summary Cardiac arrest is the final common pathway for many conditions Maternal and fetal survival depend on rapid and skilled resuscitation Consider early (< 5 min) Cesarean delivery Training in ACLS for pregnant woman essential for maternity unit personnel Be prepared!!