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

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

Case example 1. ผู้ป่วย อายุ 30 ปี น้ำหนัก 75 กก. ตั้งครรภ์ 34 สัปดาห์ ความดันเลือด 210/ 110 มม.ปรอท บวม โปรตีนในปัสสาวะ 4+ (severe preeclampsia) 2. ผู้ป่วย อายุ 30 ปี น้ำหนัก 134 กก. ตั้งครรภ์37 สัปดาห์ ความดันเลือด 200/ 110 มม.ปรอท บวม โปรตีนในปัสสาวะ (severe preeclampsia & obesity) 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) 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)

Severe Preeclampsia : definition Hypertension SBP >160, DBP > 110 mmHg Proteinuria >5 gm/24 h 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)

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

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

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

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

Management in Severe Preeclampsia. 1. ผู้ป่วย อายุ 30 ปี น้ำหนัก 75 กก 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, 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 Anesthesia for cesarean section - Choice of anesthesia - regional vs. general anesthesia regional is safer(difficult intubation) - Epidural vs. Spinal anesthesia - Epidural, - if has been used for vaginal delivery - can be used for cesarean section

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

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

Spinal anesthesia in severe preeclampsia 2005 - Large RCT* - Spinal vs. epidural *Visalyaputra S, et al. 2005 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

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

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 to blunt 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)

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

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

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

Elevated Liver Enzymes = aspartate dehydrogenase (AST) > 70 U/L 3. Anesthesia in severe preeclampsia with 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 )

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

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

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 Vaginal delivery *: systemic narcotics * Dyer RA, et al 2007 cesarean section Risk vs benefit of RA & GA should be weighed - GA : if no difficult airway detected - Spinal anesthesia (small needle, good hands)

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

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

Q & A