Medicine for the Obstetric AnaesthetistCathy Nelson-Piercy

Consultant Obstetric Physician, Guy’s & St Thomas’ Foundation Trust and Imperial College Healthcare Trust

Professor of Obstetric Medicine, King’s Health Partners

KCL Division of Women’s Health

MBRRACE - Maternal death rate 2003-12(Three year rolling averages)

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Direct and Indirect maternal death rate

Direct maternal death rate

Indirect maternal death rate

Indirect maternal deaths 1985-2011(Three year periods)

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1985-1987 1988-1990 1991-1993 1994-1996 1997-1999 2000-2002 2003-2005 2006-2008 2009-2011

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Causes of maternal death

Causes of maternal death

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Solid bars show indirect causes, hatched bars show direct causes

74% of women who died 2009-12 had a pre-existing medical disorder

Medical Problems in Pregnancy

Pre-existingAsthmaEpilepsyHypertensionDiabetesNeurologicalSLE / RA / CTDRenalCardiac

Pregnancy - specificPre-eclampsia

Thromboembolism

Gestational Diabetes

Obstetric cholestasis

Hyperemesis

Acute Fatty Liver Pregnancy

CoincidentalPneumonia, H1N1,Malaria, Hepatitis

• 1188 currently pregnant

• 5605 recently pregnant (within 42 days)

• 12.1% of total female admission aged 16-50 years

• Mean age 30

• Maternity admissions 290/100,000 maternities

• Maternal death rate 14/100,000 in 2011 CMACE report

ICNARC 2009-2012 Page 7

Pregnant Post partumObstetric 9% 70%PPH 36%Pre-eclampsia 2% 4%HELLP 0.7% 2.5%Non obstetric 91% 30%Pneumonia 23% 4.3%Pulmonary oedema

1.9% 1.6%

Pelvic infection 1.9%AKI 0.3% 0.8%Asthma 8% 0.6%Cardiovascular 8% 5.6%GI 10% 4.5%Neuro 9% 3.5%Endo 12% 1.6%

Page 9

Acute Medical Problems on Labour Ward

Chest pain

Breathlessness

Oliguria/ anuria/ AKI

Headache

Seizure

Sepsis

Page 10

Diagnosis of PE in pregnancySuspected PE

ABG, ECG, CXR

Start anticoagulation LMWH treatment dose UNSTABLE

STABLE Clinically urgent (out of hours)

DOPPLER USS LEGS

Anticoagulate with LMWH Thrombolysis/i.v. heparin/ thrombectomy

Portable echo

Suggestive of massive PE

CTPA

+ve -ve

CXR abnormalCXR normal

V/Q scan

+ve

-ve

+ve-veStop

anticoagulation

Still suspicious of PE

ABG, arterial blood gas; ECG, electrocardiogram; CXR, Chest X-ray; USS, ultrasound sonography; CTPA, computerised tomography pulmonary angiography Modified from: Scarsbrook et al. Clin Radiol 2006;61:1–12

Treatment of acute PE in pregnancy

High dose LMWH:

eg. Enoxaparin 1mg/kg/bd (= ACS dose)

NOT 1.5 mg/kg od (= non-pregnant dose)

RCOG Green Top Guideline no. 37b

Thrombolysis:SHOULD NOT BE WITHELD in massive PE, with haemodynamic instability

Ahearn et al. 2002;

Leonhardt G et al. J Thromb Thrombolysis. 2006;21:271-6.

Case 1

Page 14

SVT

Vagotonic manoeuvres are safe

Adenosine – safe

Verapamil is effective second line therapyUp to 10mg can be given without affecting fetal HR

Beta-blockers also safe

•39 yr old asian, 37 weeks pregnant

•c/o dizziness and epigastric pain

•o/e sweaty, BP 94/68, HR 84

Case 2

Case 2: which of the following are appropriate?

A. Troponin

B. Thrombolysis

C. Transfer to catheter lab

D. Primary angioplasty

E. Aspirin

F. Clopidogrel

Case 3

• 38 year old primip, 39 weeks pregnant

• C/o chest and back pain

• O/e BP 165/85, HR 124, O2 sats 97%

• Urinalysis NAD

• ‘Writhing around the bed’, ‘won’t lie down to be examined’

• Not in labour!

Page 20

• Not all chest pain and breathlessness = PE

• Beware the hypertensive (systolic) woman with chest pain

• CXR

• Echo

Acute severe asthma

Nebulized beta2 agonists + ipratropium

Oxygen – sats 94-98%

Oral / intravenous corticosteroids

Mg SO4

Intravenous theophylline

Intravenous beta 2 agonists

Consider delivery if ventilation required

Acute asthma is very unusual in labour

6/10/06

Case 4

33 year old womanReadmitted day 5 post emLSCS (for pre-eclampsia) c/o SOB and wheezyHad been discharged home day 3 post LSCS – well

O/EBreathless, sweaty SaO2 70% on RA; 100% on 15LBP 170/90 P75 SRUrine: 1+ proteinCVS: Raised JVP, HS normalChest – bilateral wheezing, scattered crepsAbdo – soft, non tenderPeripheral oedema to thighs

AIR

pH 7.49

PaCO2 4.1

PaO2 6.2

BEx 0.6

Echo normal; Diagnosis = postpartum pre-eclampsia

Postpartum pre-eclampsia

Pregnancy related hypertension and proteinuriaoccurring after 20/40

Symptoms: visual disturbance, headache, RUQ pain, peripheral / facial oedema

Incidence of pre-eclampsia: 2-5% of all pregnanciesIncidence of pulmonary oedema in PET: 2.3-2.9%

Sibai 1987 AJOG

36 year old woman, BMI 34Readmitted day 9 post elCS (for pl praevia) c/o SOB and pleuritic painHad been discharged home day 3 post LSCS – well7 day course LMWH – poor compliance; diclofenac 50 mg tds

O/EBreathless, sweaty SaO2 82% on RA; 100% on 15LBP 130/85 P78 SRCVS: Raised JVP, HS normalChest – scattered basal crepsAbdo – soft, non tenderPeripheral oedema to thighs

Case 5

ABG on Air

pH 7.39

PaCO2 4.8

PaO2 8.8

BE -3.5

Echo normal; Diagnosis = fluid overload secondary to diclofenac

Pulmonary oedema

Pre-eclampsiaReduced colloid osmotic pressureIatrogenic Fluid shiftsBeware syntocinon Beware NSAIDs

CardiacPeripartum cardiomyopathyMitral stenosisCardiac ischaemia

Drugs e.g. tocolytics, NSAIDs

Management of pulmonary oedema

OxygenStop IV fluidsDiureticsDiamorphineInvestigate cause = ECHOPPCM = Deliver / ACEIThromboprophylaxis

Peripartum cardiomyopathyDefinition: idiopathic cardiomyopathy presenting with heart

failure secondary to LV systolic dysfunction toward the end of pregnancy or in the months following delivery, where no other cause of heart failure is found. It is a diagnosis of exclusion. The left ventricle may not be dilated but the ejection fraction is nearly always reduced below 45%.

Incidence: 1 in 3000-15000 Risk factors: multiple pregnancy, age, hypertension, ethnicityMortality rate (US studies) 3-9%Failure to fully recover after one episode predicts recurrence in future pregnancy

Pulmonary arterial hypertensionSystemic ventricular dysfunction LVEF < 30%, NYHA III/IVPrevious PPCM with any residual LV impairmentSevere mitral stenosisSevere symptomatic aortic stenosisDilated Aortic root

> 45 mm Marfan> 50 mm bicuspid AoV

Severe coarctation

Advise against pregnancy

Delivery - Complex Care Plan

Physiology and cardiovascular stress of labour

Sympathetic response increases heart rateAutotransfusion increases stroke volumeIncrease cardiac output, oxygen consumption, A-V O2 diff Hyperventilation causes respiratory alkalosis

Ventricular failure,

impaired filling, outflow obstruction

Reduced colloid osmotic

pressure

Pulmonary oedema

Increased CO

Abnormal aorta or coronary

dissection arrhythmia

Vaginal delivery is generally preferable

Advantages

Less blood lossGreater haemodynamic stabilityAvoidance of surgical stressLess post-op infectionLower risk thromboembolismFewer pulmonary complications

butIt is less predictable for the teamIOL often for practical reasonsHigher risk of em LSCS

Cardiac indications for LSCS

Abnormal aortic root > 4.5 cmAortic aneurysm or dissectionSeverely impaired LV

Shortening the second stage of labour

Limiting the active second stage (pushing) in cases where the surges in BP may be particularly harmful eg aortopathy

No pushing – forceps/ventouse

Time limited – 30 mins on no evidence

Symptom limited eg ischaemic heart disease, LV failure, severe LVOTO

Uterotonic Drugs in cardiac patients

• All uterotonics have haemodynamic consequences

• However cardiac patients do not tolerate obstetric haemorrhage well.

The contraindications to uterotonics are relative.

Oxytocin

• First-line for prophylaxis and treatment of uterine atony– Rapid onset of action but short duration

• Side effects: free water retention

Tachycardia/ECG change Hypotension

• Avoid bolus – Give 5U in 50 mls saline over 20 mins– Then 40-60U in 500mls over 4-6 hrs

Br J Anaesth 2007

Prostaglandins

• PG E1 (misoprostol) selective vasodilator• Maybe used for uterine atony – less

successful than ergot +oxytocin1

• BUT best for cardiac patients….

• PG F2α (haemabate/carboprost) – causes vasoconstriction and bronchospasm

• Should be avoided especially in PHT1 Lokugamage etal. Acta Obstet Gynaecol Obstet 2007; 99: S202-5

Ergot

Reports of:

• Severe hypertension → seizure and stroke1

• Coronary vasospasm → MI2 and death3

• Elevated PA pressures and pulmonary oedema

• Normal healthy women developing severe HTN

1 Abouleish E. Anesth Analg 1976; 55: 813-52 Hayashi Y et al. Intern Med 2003;42: 983-6

3 Lin YH et al. Acta Obstet Gynecol Scand 2005; 84: 1022

Order of Use in a cardiac patient

1) Oxytocin– Diluted in at least 20 mls– Titrate to effect carefully

2) Misoprostol– 800 µg per rectum

….Go beyond if life-threatening haemorrhage……3) PG F2α

– Do not use in asthma, shunt, elevated PA pressures, single ventricle

4) Ergotamine– Do not use in pre-eclampsia, coronary artery

disease, aortopathies, aneurysms

KCL Division of Women’s Health

Thank you for your attention