Obstetric embolism

OBSTETRIC EMBOLISM

Dr. Rafaie AminConsultant Obstetrician & GynaecologistSarawak General Hospital

OBSTETRIC EMBOLISM

• AFE (Amniotic Fluid Embolism)

• VTE (Venous Thromboembolism)

Number of maternal deaths in Malaysia2006 - 2008

Causes 2006 2007 2008

Amniotic Fluid Embolism 9 17 17

Pulmonary Embolism 9 7 23

Total 18 24 40

Report on confidential inquiries into maternal deaths in Malaysia, 2006-2008

Table: Causes of maternal deaths in Malaysia; 2008-2012p

CAUSES OF MATERNAL DEATHS (MALAYSIA)

2008 2009 2010 2011 2012p

n % n % n % n % n %

Postpartum Haemorrhage

26 19.5 20 13.0 11 7.5 19 14.6 15 12.3

Hypertensive Disorders in Pregnancy

14 10.5 18 11.7 25 17.1 25 19.2 21 17.2

Associated Medical Conditions

24 18.0 51 33.1 46 31.5 37 28.5 36 29.5

Obstetric Embolism 40 30.0 23 14.9 30 20.5 16 12.3 20 16.4

Obstetric Trauma 5 3.8 4 2.6 10 6.8 12 9.2 3 2.5

Source of data : Bhg. Kesihatan Keluarga, KKM

VTE

• DVT• PE

Pregnancy

Immobility & stasis

LSCS & Other surgeries

Increased risk of VTE in pregnancy 1. Pregnancy increases risk of VTE by 6 folds 2. Increase in factor VIII, IX, X, fibrinogen 3. Decreased in fibrinolytic activity, anti-thrombin and

fall in protein S 4. Venous stasis in pregnancy5. Caesarean sections further increases the risk

approximately by 10-20 folds

Signs and Symptoms of DVT

• 50% of all DVT cases are asymptomatic • DVT signs & symptoms includes;

Swelling in one or both legsPain or tenderness in one or both legsWarmth in the skin of the affected legRed or discoloured skin in the affected legLeg fatigue

DVT

Pulmonary Embolism (PE)

• PE is a potentially life-threatening condition. • PE usually happens due to an underlying blood clot in

the leg (DVT) in over 90% of cases.• A massive pulmonary embolism carries up to 80%

risk of death

Signs & Symptoms of PE• PE symptoms vary greatly, depending on how much of the

lung is involved, the size of the clot and the overall health of the patient

• Signs and symptoms includes;Shortness of breath. Chest pain. Cough. (bloody or blood-streaked sputum)WheezingClammy or bluish-coloured skinRapid or irregular heartbeat

Diagnosis of VTE

• Clinical diagnosis of VTE has a low sensitivity.• Definitive diagnosis should be pursued in the

first possible instance.• All clinically suspected VTE should have

diagnostic testing to confirm or refute the diagnosis.

• Unresolved diagnosis causes unnecessary anxiety to both the patients and clinicians.

Diagnosing a PE

• Chest X-ray.– May be normal– May show unequal

density of the hemithorax

– Most frequent finding is a small pleural effusion .

– May show consolidation– Wedge shaped opacities– Elevated hemidiaphragm

Diagnosing PE: ECG• Tachycardia• Right axis deviation• Right bundle branch block

• S1Q3T3 - uncommon

• Changes in the ECG may be transient and may also revert to normal as the patient gets better.

Diagnosis of PE• D-dimer: if negative not likely PE• Pulmonary angiogram (CTPA)• Ventilation-perfusion scan (V/Q scan) – not widely

available

Patients suspected to have VTE / PE

• This is considered a MEDICAL EMERGENCY!• Trigger RED alert

• Consult an O&G specialist from nearest hospital• Immediate referral to nearest specialist hospital• Escort by Medical Officer where possible for the

transfer to the specialist hospital • Ask for Obstetric Retrieval Team if available

During transfer

• Ambulance must be equipped with:o BP / PR monitoringo Pulse oxymetero Oxygen and high flow masko Equipment and drugs for maternal resuscitation

Management in Specialist Hospital• Suspected PE in clinic/district hospital Urgent referral to

Obstetrician /Physician and discuss on:

o Heparinisation / anti-coagulationo Intubation (for suspected PE)o Further investigations

• Jointly managed with Physician / Hematologist / Radiologist / Anaesthetist

• Nurse in High Dependency Unit or ICU (for suspected PE)

Management of VTE

• All suspected cases of DVT / PE should have treatment commenced upon clinical suspicion.

• Objective confirmation of DVT can await until modality and its expertise becomes available.

• Diagnosis should not delay commencement of treatment (where available, 1st dose of anticoagulation therapy should be given prior to transfer)

Treatment: Drug of choice

• The treatment of choice for VTE in pregnancy is low molecular weight heparin (LMWH) LMWH is superior to UFH in terms of efficacy.UFH is associated with more side effects.

• The following LMWH is recommended in pregnancy:1. Enoxaparin2. Tinzaparin3. Dalteparin

LMWH

• Routine monitoring of platelet counts is not indicated.

• Anti-Xa level monitoring is not indicated unless when the weight is less than 50kg or more than 90kg.

• The target level is 0.5-1.2

• Sampling should be done 4 hours post dose.

Anticoagulation: LMWH• Enoxaparin: 1 mg/kg subcutaneously every 12 hours

• Tinzaparin: 175 IU/kg subcutaneously OD

• Dalteparin: 150-200 IU/kg subcutaneously OD (max dose 18,000 IU daily)

• For DVT, repeat doppler studies after 5 - 7 days of

anticoagulation to check if clot has resolved!

Anticoagulation: UFH

Subcutaneous: 10,000 IU twice dailyIV Infusion:

5000 IU stat bolus followed by 1000 IU/hour by continuous IV infusion.

Bolus dose of 80 IU/kg IV stat followed by 18 IU/kg/hour by continuous IV infusion

The dosage adjusted to maintain the aPTT at 1.5 to 2.5 Platelet counts to be monitored daily during IV treatment &

weekly for 4 weeks then monthly during SC treatment. Heparin-induced thrombocytopenia is rare

Duration of treatment

• Depends on the cause • Outside pregnancy a total of 3 - 6 months treatment is

recommended.

• In pregnancy therapeutic doses is to be continued through pregnancy till 6 weeks postpartum.

• Within the 6 weeks postpartum, therapy should be extended to complete a minimum total treatment duration of 3 months.

LMWH- Regional anaesthesia

• Wait at least 12 hours after a prophylactic dose before block• Wait at least 24 hours after a therapeutic dose before block• Wait at least 10 hours after dose before removing catheter• After catheter removal wait 2 - 4 hours before next dose• To stop injections 24 hours before a planned delivery

(induction or caesarean)• Advised to omit injection at onset of labour

LMWH – regional anaesthesia & labour

UFH: regional anaesthesia & labour

Unfractionated heparin (subcutaneous)• Wait at least 4 hours after a dose before block or catheter removal• Wait at least 1 hour before dosing after procedure (catheter insertion or withdrawal)Unfractionated heparin (intravenous)• Stop infusion 2-4 hours before block• Start infusion > 1 hour after block• Remove epidural catheter no sooner than 2 - 4 hours after

discontinuation of infusionLabour – stop at onset of labour

Treatment: Postpartum• Active management of 3rd stage• PPH prophylaxis should be instituted

Blood grouped and savedlarge IV access 40 units oxytocin infused after delivery of placenta

• Therapeutic dose can be recommenced 4 hours postpartum (also for operative delivery)

• LSCS- recommended to insert drain

Treatment:

• Use of warfarin for maintenance therapy may be considered in the 2nd trimester up to 36 weeks or in the postnatal period.

• Women should be counseled that both heparins and warfarin are safe during breastfeeding.

Treatment: Unstable PE

• In severe cases of PE with cardiorespiratory compromisea) Consider thrombolytic therapy (e.g. alteplase,

streptokinase) although no clear survival benefits have been established.

b) Complications include 3-5% non-fatal maternal haemorrhage and 2% fetal demise.

c) If all fails, get cardiothoracic input for thoracotomy (Pulmonary embolectomy)

Does guidelines work?

• There has been a significant decline in deaths from PE following the publication and implementation of guidelines that were recommended in previous confidential enquiry reports. (Confidential Enquiry into Maternal Deaths, UK)

• The number of deaths in the UK attributed to PE were 18 between 2006-2008 compared to 41 in 2003-2005.

• Evidence that clinical guidelines works…..

CPG on VTE

• Published in August 2013• “All women should be assessed at

booking and after delivery or if they are admitted to the hospital for any reason or develops other problems”

• “All should be stratified into risk groups according to risk factors and offered thromboprophylaxis with LMWH where appropriate”

Strategy to reduce risk of VTE in pregnancy

• Modifying risk factors in women planning to embark on pregnancy – PPC Clinic

• Improve awareness among health staff and public• Guidelines• Appropriate management of pregnant women based

on VTE risk stratification

Patients with known Risk FactorsPRE PREGNANCY• High risk patients contemplating pregnancy e.g.:

1. Previous history of VTE /PE2. Protein S and Protein C deficiencies3. Collagen diseases especially SLE4. Anti-phospholipid Antibody Syndrome5. Other risk factors e.g. obesity, elderly, hypertensive, ART, smoker,

varicose veins, paraplegia, IV drug users

• Refer to PPC clinic: Health clinics with FMS O&G Specialist clinics

PPC Clinic

• Counseling on individual risk of VTE• To reduce BMI below 30kg/m2• Stop smoking• Limit number of pregnancies• Optimizing chronic medical illnesses• Effective and appropriate contraception

VTE Risk factors• Age above 35 years • Weight > 80kg or pre pregnancy/

booking BMI> 30 • Parity > 3 • Past history of thromboembolism • Thrombophilia • Gross varicose veins • Immobility e.g. long haul travel,

hospital stay > 3 days • Pre-eclampsia • Caesarean section • IV drug user

• Prolonged labour > 12 hours or instrumental deliveries

• Medical conditions: a) heart disease (especially

prosthetic valves) b) nephrotic syndrome c) systemic inflammatory

diseases. • Massive postpartum haemorrhage • Systemic infection • Hyperemesis gravidarum • Dehydration • OHSS

Antenatal Assessment

VERY HIGH RISK• Recurrent VTE associated with either anti-

thrombin deficiency or anti-phospholipid syndromeRequire higher dose of LMWH (high prophylactic

12-hourly or 75% of treatment dose)Antenatal + 6 weeks postnatal or until conversion

to warfarin

Antenatal Assessment

HIGH RISK• Single VTE with thrombophilia or

unprovoked / estrogen-related • Previous recurrent VTE (>1 episode)

Require antenatal + 6 weeks postnatal thromboprophylaxis

Antenatal Assessment

INTERMEDIATE RISK• Single previous VTE with no family history or

thrombophilia• Thrombophilia but no VTE• Has medical co-morbidities• Intravenous drug user• Surgical procedure Consider antenatal + 7 days up to 6 weeks postnatal

thromboprophylaxis

Antenatal Assessment

• All women must undergo documented assessment for VTE risk at the following:a)Pre-pregnancy (@ PPC Clinic)b)Early pregnancy (@ booking)c)Every admission

Postnatal Assessment

• All postpartum women must undergo documented assessment for VTE risk

• Encourage ambulation • Avoid dehydration• Advised to seek treatment early in nearest health center

if feeling unwell • LMWH is the agent of choice • LMWH & warfarin are safe during breastfeeding

VTE Training Manual 2012

54

Postnatal Assessment – Risk Factors

• All antenatal risk factors• Anyone requiring antenatal thromboprophylaxis• Caesarean section (Emergency & Elective)• Mid-cavity rotational operative delivery• Prolonged hospital admission ( > 3 days)• Prolonged labour (>12hours)• PPH >1.5L or blood transfusion

Postnatal Assessment – Risk Categories

• HIGH RISK: require at least 6 weeks postnatal thromboprophylaxis

• INTERMEDIATE RISK (score > 2): consider at least 7 days of postnatal thromboprophylaxis

• LOW RISK (score of < 2): advise on mobilization and adequate hydration

• NEW GREEN TOP GUIDELINE: at least 10 days postnatal prophylaxis for score of 2 or more

VTE Training Manual 2012

56

RISK FACTORS: Tick Tick Discharge(Tick)

Score

DATE:

ANTENATAL:

Previous VTE (estrogen related, unprovoked or recurrent) 3

Previous VTE (provoked, eg accident) 2

Thrombophilia 2

Medical illness (SLE, Cardiac, Connective tissue, Renal disease, Malignancy)

2

Family history of VTE 1

Age >35 years 1

Parity > 3 1

Obesity a) (BMI>40kg/m2) 2

b) (BMI>30kg/m2) 1

Gross varicose veins 1

Smoker/ IVDU 1

Multiple pregnancy 1

CURRENT EVENTS OR ADMISSION:

Hyperemesis Gravidarum requiring admission 1

Pre-eclampsia 1

Dehydration/ OHSS**

Hospital stay / immobilization > 3days 1

Systemic infection (eg active TB, pneumonia) 1

Chorioamnionitis 1

Surgery in pregnancy or puerperal period (includes BTL within 42 days of delivery. Exclude ERPOC & minor T&S*)

1

Long travel by road/air travel > 8 hours non stop 1

DELIVERY (CURRENT PREGNANCY):

Caesarean section (emergency & elective) 2

Instrumental delivery 1

PPH > 1.5 L 1

Prolonged labour > 24 hours 1

Third/fourth degree perineal tear 1

Vulvo/vaginal haematoma 1

Septic miscarriage/ Molar pregnancy 1

TOTAL SCORE

Name of 1st assessor

Name of 2nd assessor

Name of 3rd assessor

Sarawak VTE Risk Assessment Form (Hospitals)Name: NRIC: Assessment should be performed:

• At antenatal booking• During each hospital admission• Reassessment whenever required• Post delivery before discharge

When to give thromboprophylaxis:1) ANTENATALLY – score > 3 (duration of

thromboprophylaxis to be decided or discussed with an O&G specialist)

2) POSTNATALLY – score > 2 (Rx duration for 7 days)

Weight Enoxaparin (Clexane)

S/C Heparin Tinzaparin (Innohep)

<50kg 20mg OD - - 50-90kg 40mg OD 5000 units BD 4500units OD

91-130kg 60mg OD Insufficient evidence of efficacy

7000units OD

131-170kg 80mg OD 9000units OD

Dosage for thromboprophylaxis:

SARAWAK VTE RISK ASSESSMENT FORM:

NEW RECOMMENDATIONS FROM THE JUST RELEASED GREEN TOP GUIDELINES, APRIL 2015 ON VTE IN PREGNANCY

SOME OF THESE RECOMMENDATIONS WOULD BE IMPLEMENTED IN THE STATE…..

Sarawak VTE Risk assessment Form (May, 2015)

Antenatal assessmentAntenatal assessment

Score < 3 SCORE 3 Score > 4

< 28 WKS >28 WKSCounselling on ambulation, avoid dehydration, +/- compression stocking

Reassess risk if requires prolonged admission or develops new problems

Non specialist hospital

Specialist hospital

Coded yellow

Discuss with Buddy Specialist or O&G specialist on-call

Initiate thromboprophylaxis (consult O&G specialist if unsure of duration)

Shared care between MO/FMS/Specialist

E-Discharge Notifications (specific instructions, home visits)

Home visit by health staff (review compliance, symptoms’- use check list)

FMS/ Specialist follow up but shared care allowed

Coded yellow

Initiate thromboprophylaxis

Documented follow up plans

E-Discharge Notifications (specific instructions)

Home visit by staff (review compliance, symptoms’- use check list)

Follow-up with specialist clinic or shared care

MANAGEMENT FLOWCHART - MAY 2015

• ANTENATALLY – score > 4 (other than for previous VTE or thrombophilia), consider thromboprophylaxis from 1st trimester and may consider to continue up to 6/52 postnatally after risk reassessment (specialist decision)

• ANTENATALLY – score 3 (other than for previous VTE or thrombophilia), consider thromboprophylaxis from 28 weeks onwards

• POSTNATALLY – score > 2 (other than for previous VTE or thrombophilia), consider thromboprophylaxis for at least 10 days

Who should be given thromboprophylaxis?

• LMWH is the preferred thromboprophylaxis

• Antenatal women admitted for hyperemesis gravidarum, OHSS or surgery (score of 4 each): consider prophylaxis with LMWH unless there is a specific contraindication (e.g. risk of bleeding)

• In hyperemesis gravidarum & OHSS, VTE prophylaxis should be given until the relief of symptoms

• IVF pregnancy & dehydration are considered risk factors (score of 1 each)

Other new recommendations

• Women who had emergency caesarean section (score of 2) should be given VTE prophylaxis for 10 days after delivery.

• Women who had elective caesarean section (score of 1) plus 1 other risk factor should be given 10 days of VTE prophylaxis

• • If heparin was used after caesarean section (or other surgery), the

platelet count should be monitored every 2-3 days from day 4-14 or until heparin is stopped

• Women with recurrent VTE require higher doses of LMWH and co-managed with a Hematologist/Physician

Other NEW recommendations :

VTE Checklist during home visits by nurses:

If a patient develops any of these signs or symptoms, refer immediately to the nearest clinic or hospital for review by a doctor.

Patients should be advised to ambulate, drink adequately and to seek medical treatment if feeling unwell during every visit

Check if the patient is compliant to treatment

THROMBOEMBOLISM CHECK LIST FOR ANTENATAL OR POST-NATAL HOME VISITS:

1) General well-being Y N

a) Is the patient ambulating? b) Is the patient drinking well? c) Does the patient look dehydrated? d) Does the patient have fever?

2) Signs & symptoms’ of DVT Y N a) Leg swelling (usually unilateral) b) Calf pain (even at rest) c) Redness of calf d) Feeling unwell (unable to mobilize) e) Non pitting swelling f) Increased warmth of the limb g) Reduced capillary filling

3) Signs & symptoms’ of pulmonary embolism Y N a) Shortness of breath b) Chest pain (more during breathing) c) Cough (dry or blood stained) d) Pulse rate >100 e) Respiratory rate >24 f) Cyanosis g) Unconscious

Please note:

If a patient develops any of these signs or symptoms, refer immediately to the nearest clinic or hospital for review by a doctor.

Please advise patients to ambulate, drink adequately and to seek medical treatment if feeling unwell during every visit

Please ensure if the patient is compliant to the medication or injections being prescribed

Assessed by:

Name: ………………………………………………….. Signature: …………………………………………….. Date: ………………………

MMR Sarawak 1998 – 2013(direct & indirect causes)

Excluding foreignersSource of data : maternal mortality report 2003, SHD, MOH Enquiry of maternal death 2005; SHD enquiry list

15 deaths due to PE from 2008-2012

4 deaths due to PE in 2012

1 PE death in 2013

VTE- contraception

• Progestogen only pills• Implanon• Mirena & Cu- IUCD • Depo-provera • Avoid combined OCP, transdermal patches &

intravaginal rings

Do not increase risk of VTE

RECOMMENDATIONS• Definitive diagnosis of DVT/PE in pregnancy should be obtained

for all cases as it carries a long- term implication for future pregnancies.

• All at-risk patients in pregnancy and postpartum should be offered thromboprophylaxis.

• A standard checklist should be developed and used by the O&G services.

• The percentage of compliance to these checklists should be monitored at the hospital level.

• Awareness and the importance of thromboprophylaxis should be increased among the nursing personnel and junior medical officers

Case scenario 1

37 year-old woman at 28 weeks of gestation with PE. Her BMI is 35. She complained of leg swelling that makes it difficult to walk. 1. How is pedal oedema of pregnancy different from swelling of

DVT? 2. What are the risk factors present for DVT in this woman? 3. Upon assessing, you find that the woman most likely has DVT

of the right leg. What are your possible actions? 4. At the receiving hospital, you think it would be DVT. What

are your actions? 5. How do you diagnose a lower limb DVT?

1. Pedal oedema is usually bilateral. DVT of the lower limb is usually unilateral and it may be red, warm and tender

2. Risk factors: Gender, age, BMI, PE, immobility, pregnancy 3. Refer to MO/FMS/O&G specialist, arrange to be reviewed

urgently in clinic or ETD4. Confirm diagnosis then treat OR start treatment and confirm

diagnosis. Anticoagulation with heparin/LMWH/warfarin. Give analgesia, TED stocking, elevate leg +/- antibiotics

5. Investigations: pulsed Doppler or venogram

Case scenario 1: answer

Case scenario 2

35years old para 2 post SVD day 5, no antenatal complication or post natal complication till date. She complained of swollen left lower limb and mild chest discomfort upon review during the home visit on day 5. 1. What should be checked? 2. What is the next step? 3. While arrangement was being made for admission she

suddenly complained of pleuritic chest pain and SOB? 4. What do you do?

Case scenario 2: Answer

1. CHECK LIST – home visit postnatal check list 2. High suspicion of DVT, refer to be reviewed in

clinic with MO/FMS stat. Advisable for admission for confirmation of diagnosis.

3. Suspicion of PE. 4. Urgent referral and arrange transfer to nearest

specialist hospital. If heparin is available initiate anticoagulation after discussing with O&G specialist/Physician

Thank you!