Anesthesia in severe preeclampsia

1. Anesthesia in severe preeclampsia Shusee Visalyaputra Siriraj Hospital Mahidol University Thailand.

2. Outline • 4 case examples • Definition & pathophysiology 3. Management -preoperative evaluation - anesthetic management in each case - anesthesia for vaginal delivery - anesthesia for cesarean section - choice of anesthesia epidural anesthesia spinal anesthesia general anesthesia 4.Q & A

3. 2. ผู้ป่วย อายุ 30 ปี น้ำหนัก 134 กก. ตั้งครรภ์37 สัปดาห์ ความดันเลือด 200/ 110 มม.ปรอท บวม โปรตีนในปัสสาวะ (severe preeclampsia & obesity) Case example 3. ผู้ป่วย . อายุ 32 ปี น้ำหนัก 70 กก. ตั้งครรภ์ 32 สัปดาห์ ความดันเลือด160/ 100 มม.ปรอท บวม เจ็บใต้ชายโครงขวา โปรตีนในปัสสาวะ 4+ ผลตรวจทางห้องปฏิบัติการพบ เกล็ดเลือดต่ำ 63,000/ มม3 หน้าที่ตับผิดปกติ (an aspartate aminotransferase (AST) > 70 U/L, lactatedehydrogenase (LDH) > 600 U/L), Bilirubin 1.mg/dL ( HELLP syndrome, which is one form of severe preeclampsia) 1. ผู้ป่วย อายุ 30 ปี น้ำหนัก 75 กก. ตั้งครรภ์ 34 สัปดาห์ ความดันเลือด 210/ 110 มม.ปรอท บวม โปรตีนในปัสสาวะ 4+ (severe preeclampsia) 4. ผู้ป่วย อายุ 30 ปี น้ำหนัก 65 กก. ตั้งครรภ์ 35 สัปดาห์ มีอาการชัก1ครั้งก่อนมารพ ความดันเลือดสูง 200/ 120 มม.ปรอท บวม โปรตีนในปัสสาวะ 4+(Eclampsia, which is one form of severe preeclampsia)

4. Hypertension SBP >160, DBP > 110 mmHg • Proteinuria >5 gm/24 h Severe Preeclampsia : definition • Either one of end organ damage- Oliguria (<400 ml/24 h) - Cerebral edema - blurred vision, headache, convulsion - Pulmonary edema - Hepatic dysfunction - epigastric pain, HELLP - Intrauterine growth retardation (IUGR)

5. Pathophysiology first trimester Invasion of trophoblast incomplete maternal spiral arteries  placental ischaemia  released of inflammatory stimuli  second trimester endothelial cells damage, dysfunction  cytokines production  & vasoconstriction, platelet aggregation hypertension & proteinuria & end organ damage

6. Renal - proteinuria, oliguria Hepatic - elevated liver enzymes, - liver cells damage, HELLP Heart - cardiomyopathy Pathophysiology : End organ dysfunction or damage CNS - cerebral edema eclampsia Lung - pulmonary edema “no known about unequal involvement of each organs in each patient”

7. Cerebral dysfunction Airway edema Pulmonary edema Severe hypertension, tachycardia Liver dysfunction t Urine output Fetal well being Preoperative Evaluation Global Endothelial cells Dysfunction = Every organs involvement

8. Fluid- lack of evidence support* - 80 ml/h (by expert opinion) Drugs-uncertainty in drug of choice to treat hypertension * * - use with local experience, on known side effects (by expert opinion) *Duley L, et al. Cochrane database 2000 * Young PF 2000 **von Dadelszen P, et al 2007 Management in Severe Preeclampsia CVP-no correlated with PCWP at >8 mmHg - keep CVP 4-6 mmHg (by expert opinion)

9. Anesthesia for vaginal delivery - Epidural anesthesia - better pain relief - attenuate BP response to pain - better control of maternal BP - improved utero placental blood flow - can be used for cesarean section Management in Severe Preeclampsia 1. ผู้ป่วย อายุ 30 ปี น้ำหนัก 75 กก. ตั้งครรภ์ 34 สัปดาห์ ความดันเลือด 210/ 110 มม.ปรอท บวม โปรตีนในปัสสาวะ 4 + (diagnosis = severe preeclampsia) normal coagulation profiles, Platelet count 150,000 mm3,

10. Anesthesia for cesarean section - Choice of anesthesia - regional vs. general anesthesia regional is safer(difficult intubation) Management in Severe Preeclampsia - Epidural vs. Spinal anesthesia - Epidural, - if has been used for vaginal delivery - can be used for cesarean section

11. 20 yrs • Avoid RA (hypotension might compromise NB) - small prospective study* - CSE, Epidural, GA - no sig. dif. in BP, NB 1995 12 yrs - large retrospective study** - spinal & epidural anesthesia - no. sig. dif in BP, NB 1999 8 yrs * Wallace, et al 1995 **Hood DD & Regina 1999 Spinal anesthesia in severe preeclampsia

12. * spinal anesthesia severe preeclampsia vs healthy parturient frequent of hypotension 16%53% 1b, A 2003 **- spinal vs GA - severe preeclampsia with nonreassuring fetal heart trace 1b, A 2003 Hemodynamic changes – similar 1 min Apgar - lower in GA gr. 5 min Apgar - similar Umbilical pH - 7.20 vs. 7.23 * Aya et al, 2003 **Dyer et al, 2003 Spinal anesthesia in severe preeclampsia

13. 2005 - Large RCT* - Spinal vs. epidural *Visalyaputra S, et al. 2005 Spinal anesthesia in severe preeclampsia Hypotension = 51% vs. 33% Degree of hypotension =10 mmHg (95% CI 4-17 mmHg) Period of hypotension = median 1 vs 0 min Ephedrine requirement = median 6 vs 0 mg 1&5 min Apgar Scores = similar Umbilical blood gas = similar

14. General Anesthesia in Preeclampsia • Airway edema is common - Mandatory to reexamine the airway soon before induction, then make decision to go on rapid sequence induction or awake intubation or spinal block (mother,s life Vs baby,s life) (giving a dead new born to the alive mother is better than giving a dead wife to the alive husband) • Laryngoscopy and intubation may  severe BP • Labetolol & NTG are commonly used acutely • Nifedipine 10 mg SL,hydralazine 20 mg titration • Fentanyl (2.5 mcg/kg), alfentanil (10 mcg/kg), lidocaine may be given to blunt response

15. General Anesthesia in Preeclampsia • Steps of GA -Evaluate upper airway - Antacid prophylaxis,LUD - Non invasive monitoring • Decrease BP to around 140/90 mmHg by using - Labetolol & NTG are commonly used acutely - Nifedipine 10 mg SL,hydralazine 20 mg titration • Fentanyl (2.5 mcg/kg), alfentanil (10 mcg/kg), lidocaine may be given toblunt response • Thiopenthal,S Choline, cricoid pressure • S Choline, nitrous oxide, 1/4 Mac. volatile agents • Narcotics after delivery • Awake extubation • Postoperative closed observation (respiration. BP,urine output, consciousness)

16. Conclusion in patient no.1 (severe preeclampsia, with platelets > 100,000 mm3 not obese) Vaginal delivery: epidural anesthesia Cesarean section: Epidural or CSE is still the technique of choice, although nowadays, good evidences support the use of spinal anesthesia in preeclamptic patients (with platelets count > 100,000/mm3). GA, if needed,airway should be evaluated first, decrease BP before intubation, postop close observation for residual relaxation, hypertension,pulmonary edema,eclampsia

17. patient no.2 (severe preeclampsia with obesity)

27. Conclusion in patient no.2 (severe preeclampsia with obesity) Vaginal delivery: epidural anesthesia (sitting) Cesarean section: Epidural or CSE(sitting): the technique of choice but may be difficult, Spinal(sitting): may be easier & nowadays, good evidences support the use of spinal anesthesia in preeclamptic patients (with platelets count > 100,000/mm3). GA, (severe preeclampsia + obesity + emergency = bad combination), airway should be evaluated before rapid sequence induction, if looks difficult, change to RA or awake intubation

28. 3. Anesthesia in severe preeclampsiawith platelets <100,000/mm3 (HELLP) HELLP Syndrome (Hemolysis = abnormal peripheral smear,(bilirubin >1.2 mg%, LDH > 600 U/L) Elevated Liver Enzymes = aspartate dehydrogenase (AST) > 70 U/L Low Platelets = <100,000/mm3 )

29. *Dexamethasone 6 mg q 6 h x 4 doses steroid without steroid Platelets count 88,000 + 40,000 vs. 72,000 + 20,000/mm3 3b, B 3b, B 4, C ** 37 patients with platelet <90,000/mm3 steroid without steroid RA used 42% (11/26)0% (0/11) *O’ Brien JM, et al 2002 **Martin JN Jr, et al 2003 Dexamethasone can increase RA rate in HELLP Syndrome

30. Tromboelastogram (TEG) - measure all phase of blood coagulation - 14% of severe preclampsia have platelet count <100,000/m3 * Maximum Amplitude (MA) of 53 (normal) is correlated with platelet count 54,000/mm3 (95% CI 40,000-75,000) 4, C *Orlikowski CE, et al 1996 Sharma SK, et al 1999 Which level of platelet count that RA can be used?

31. Vaginal delivery *: systemic narcotics * Dyer RA, et al 2007 Conclusion in patient no.3 HELLP syndrome, (platelets < 100,000 mm3 ) • Since severe preeclampsia has dynamic status of the disease, recent platelet levels should be determined before performing RA cesarean sectionRisk vs benefit of RA & GA should be weighed - GA : if no difficult airway detected - Spinal anesthesia (small needle, good hands)

32. Pathophysiology* - hyperperfusion & loss of autoregulation (rather than focal ischaemia) - vasogenic edema in MRI RA in Eclampsia ** - 66 stable eclamptic patients, - 37 epidural, 2 spinal 4 , C * * * - use GA in patients with depressed level of consciousness, ventilation into postpartum. - use RA in patients with normal levels of consciousness 5 , D * Belfort MA, et al 2006 ** Moodley J, et al 2001 *** Dyer DA, 2007 patient no.4 (Eclampsia)

33. Final Conclusion:Severe Preeclampsia Vaginal delivery: epidural or systemic analgesics Cesarean section elective - epidural, spinal,CSE urgency, non reassuring fetal heart trace - spinal emergency, severe fetal bradycardia (prolapsed cord) - GA (evaluate upper airway, then rapid sequence, awake or change to RA) In HELLP, patients with platelet count <100,000/mm3 GA or spinal ( if platelet>75,000/mm.3) In Eclampsia RA is suggested in stable eclamptic patient with good consciousness

34. Q & A