Postnatal Thromboprophylaxis

7/28/2019 Postnatal Thromboprophylaxis

1/10

1

Policy 3.7-07WACS

Title: POSTNATAL THROMBOPROPHYLAXIS

Description: Postpartum ThromboprophylaxisTarget Audience: All Obstetric Medical Staff, Anaesthetists, Midwives, PharmacyKey Words: Postnatal Thromboprophylaxis

Policy Supported: LGH Womens & Childrens Services - Clinical Protocol

Purpose:

This Procedure dictates the measures to be taken to minimise the incidence of venous

thromboembolism (VTE) in postnatal women.

The procedure does not deal with

1. postnatal prophylaxis for women already on antenatal prophylaxis

2. therapy of established VTE

3. antenatal prophylaxis

4. diagnosis of VTE

Background:

Pregnant women have a 5 to 10-fold increase in VTE compared with non-pregnant women

giving an incidence of clinical VTE of about 1 per 1000 (Doyle 2004, RCOG 2004). Few

figures are available for the rate of subclinical VTE in pregnant women.

While there is an equal distribution of VTE throughout pregnancy, the daily risk is greatest

in the few weeks following delivery.

VTE is the commonest cause of maternal death in Australia with an incidence, in the last

reported triennium (1994-6) of 9 deaths 8 with VTE as major cause, 1 with VTE as

contributory cause (ectopic). This is a rate of VTE deaths to total pregnancies of just over 1

per 100,000. Of these 9 deaths, six were postpartum, two were in the first trimester and

one was at 33 weeks.

The risk after caesarean is considerably increased. Only 20% of women were delivered by

caesarean (C/S) in the above report, but 4 of the 6 postpartum deaths from VTE occurred

in women whod had a caesarean birth. The reason for the caesarean e.g. severe pre-

eclampsia, is often a contributing factor but surgery itself greatly increases VTE.

Womens & Childrens Services

Policy August 2006

SDMS ID: P2010/0307-001


2/10

2

POSTNATAL THROMBOPROPHYLAXIS (TP) THERAPIES

1. All postnatal womenAdequate hydrationEarly mobilisation

2. High-risk postnatal women defined as:-

a. All caesarean (CS) deliveries or extended pelvic surgery e.g. hysterectomy for PPHb. Vaginal deliveries with 4 or more risk factors:i. General Risk Factors

1. Age > 35 years2. Booking BMI > 30kg / m2 *

3. Para 4 or more

4. Major intercurrent illness5. Major current infection6. Gross varicose veins7. Heterozygous Factor V Leiden or Prothrombin Gene Mutation8. Family history of VTE in first degree relative

Pregnancy-related Risk Factors1. Pre-eclampsia2. Immobility 4 days or longer3. Labour >12 hours4. Forceps/ventouse delivery5. Major blood loss

morbidly obese women (Booking BMI >40) should have postnatal TP even if noother risk factors are present

High risk women are to be given Low Molecular Weight Heparin (LMWH) Enoxaparine(Clexane):-

40mg s.c. on a once-daily basisthe first dose should be given within 4 hours of delivery, usually on return to the ward ordelivery suite HDU, unless there are specific written instructions in the operation report andmedication chart that it is to be withheld or delayed.subsequent doses should be given nocte from the first post-operative dayadministration should be away from wound site (alternating lateral upper thigh suitable afterCS)at least 2 hours must elapse between insertion or removal of epidural / spinal andsubsequent Clexane administration i.e. wait 2 hours after insertion/removal ofepidural/spinal before giving ClexaneAt least 12 hours must elapse between last prophylactic dose of Clexane and subsequent

insertion or removal of an epidural / spinal (24 hours if therapeutic doses) i.e. wait 12 hoursafter Clexane before inserting or removing epidural / spinal. Liaise with the AnaestheticService is advisable.administration should be continued daily until discharge or until Day 5 if mobilising well byserum platelet levels usually do not need to be checked (see below)

Very High Risk postnatal women defined as:-a. Paralysis of lower limbsb. Homozygous Sickle Cell Disease (HbSS)c. Previous spontaneous VTE (i.e. no probably cause)d. Previous provoked VTE with any thrombophiliae. Lupus anticoagulant or high-titre anticardiolipin antibody

f. AT III, Protein C, Protein S deficiency (on non-pregnant serum sample)g. Homozygous Factor V Leiden or Prothrombin Gene Mutation, or double

heterozygote


3/10

3

These women are to be given Low Molecular Weight Heparin (LMWH) Enoxaparine (Clexane)as above but continuing for8 weeks post-partum. Consultation with haematologists is advisable.Serum platelet levels will need to be checked (see below).

MONITORINGTESTING SERUM PLATELET LEVELS POSTNATALLY

No previous LMWH received in previous three months:-o Women having LMWH for 5 days or less do not need platelets checkedo Women still on LMWH on Day 6 should have platelets tested. Further testing should

occur second-daily until Day 14 (or until woman ceases LMWH if less that 14 days)o If platelets normal and patient remains on LMWH, thereafter check platelet levels

monthlyo Cease LMWH if platelets drop below 50% of pre-treatment level or below 100 x 10 9/L.

Seek urgent haematological review.LMWH received in previous three months, then discontinued, now recommenced *:-

o Begin testing platelet levels on Day 2o Test second-daily until Day 14o If platelets normal and patient remains on LMWH, thereafter check platelet levels

monthlyo Cease LMWH if platelets drop below 50% of pre-treatment level of 100 x 10 9 / L. Seek

urgent haematological review

*This does not apply to women who have been on LMWH in the antenatal period who arecontinuing it without a break into the postnatal period who only require platelet testing once amonth.

CONTRA-INDICATIONS TO THROMBOPROPHYLAXIS WITH CLEXANE1. Majorantepartum or postpartum blood loss which is not yet stable.2. Blood epidural/spinal3. Renal Impairment:

a. Clexane should be used in caution in women with impaired renal function.

b. Standard Heparin S/C may be used as an alternative in such patients (5000u b.d.or t.d.s)c. Alternatively Clexane dosage should be modified according to the hospital protocol

for Clexane in the presence of renal failure. (Appendix 2).

OTHER THERAPIES1. Intermittent Pneumatic Compression (IPC) In Addition to Clexane)

a. All pregnant women should have IPC used intra-operativelyb. Postnatal women nursed in the delivery suite HDU for severe pre-eclampsia or

other serious medical conditions are a particularly high-risk group and should haveIPC commenced intraoperatively and continued without interruption (except forshowering and ambulation) for 5 days or until full mobilisation / discharge.

2. Intermittent Pneumatic Compression (IPC) In Lieu of Clexanea. Occasional women will not be suitable for Clexane e.g. major antepartum or

postpartum blood loss which is not yet stable or particularly bloody epidural / spinal.Such women should have IPC commenced intraoperatively and continued withoutinterruption (except for showering and ambulation) for 5 days or until fullmobilisation / discharge. Clexane should be started when considered safe.

3. Graduated Compression Stockings (GCS)a. Well-fitted BCS are effective in VTE prophylaxis in non-pregnant women but have

not been adequately studied in pregnant women.b. GCS are probably less effective in thromboprophylaxis than LMWH and prolonged

IPC.c. GCS have little to add to TP in patients already on LMWH or prolonged IPC and

therefore have only limited place in the postnatal woman. In general, women usingprolonged IPC do not also need GCS.


4/10

4

d. GCS may have a place in antenatal women on prolonged bed rest.

4. WarfarinWomen who may require prolonged postpartum TP may be switched to Warfarin in thepostnatal period. When no contra-indications exists (eg: active bleeding) Warfarin maybe commenced 24 hours postpartum with the Clexane continuing until therapeuticWarfarin levels are achieved.Breastfeeding is not contra-indicated with Clexane or Warfarin.

ANTENATAL PROPHYLAXISWhile full consideration of antenatal TP is outside the scope of this postnatal procedure, thefollowing should be noted:

High-risk women with significant thrombophilia or previous VTE will often require antenatalanticoagulation with LMWH in either prophylactic or therapeutic doses. Such women should bemanaged on a case by case basis, usually in consultation with the haematology department.Low-risk women on bed rest (placenta praevia, PPROM, short cervix) have a significantlyincreased tendency to VTE. Consideration should be given to the use of well-fitting below-knee GCS in such women.

Attachment 1. Abbreviations

Attachment 2. Clinical Notes

Attachment 3. References

Signature: Dr A Dennis _____________________Co-Director- MedicalWACS

Sue McBeath _____________________Co-Director NursingWACS

Date: _______________________


5/10

5

ATTACHMENT 1.

Abbreviations: -

BMI Body Mass Index measured as kg / m

CS Caesarean SectionDVT Deep Vein ThrombosisGCS Graduated Compression Stockings (previously known as TEDS)IPC Intermittent Pneumatic Compression (calf compressors)LMWH Low Molecular Weight HeparinPE Pulmonary Embolus / EmbolismPPH Postpartum HaemorrhagePPROM Premature Preterm Rupture of MembranesTP ThromboprophylaxisUH Unfractionated heparinV/Q SCAN Ventilation Perfusion Lung Scan looking for evidence of PE

VTE Venous Thromboembolism


6/10

6

ATTACHMENT 2.

Some pregnant women have an even higher risk but there currently exists little data to

allow quantification of the magnitude of each risk factor.

Little data exists regarding efficacy of VTE prophylaxis in pregnant women (Gates 2002)

The risk after caesarean can be significantly modified by thromboprophylaxis. Following

the 1995 introduction of post-caesarean TP in the UK, the VTE deaths after CS dropped

from 15 (1994-6) to 4 (1997-9). In the recently released 2000-2002 Report, the deaths after

CS had jumped back up to 10 out of 17 postnatal deaths, often because indicated TP was

inadequately provided.

VTE is common after spontaneous vaginal delivery as well, with over 90% of the vaginal

deliveries which resulted in fatal VTE being spontaneous rather than instrumental (9 of 10

in 1997-9 RCOP Report; 7 of 7 in 2000-2 RCOG Report). Most of these women were

either >35 years and/ or obese.

Of the 17 postnatal VTE deaths in the latest 2000-2 UK report, 16 had clearly identifiable

risk factors, many of which were not recognised.

Age is a major risk factor. A woman aged 40 years has sixty times the rate of VTE of a

woman aged 25 years (RCOG 1995). In non-pregnant women, the rate of VTE for a 15 y.o.

is < 5 per 1000,000 while the rate for an 80y.o. is 500 per 100,000 (White 2003)

Obesity is a major risk factor for VTE. A linear relationship exists between BMI and risk of

VTE.

While this Procedure only deals with postpartum TP, the increased thrombotic risk existsfrom the beginning of the first trimester. About three-quarters of antenatal deaths occur in

the first trimester. (8 of 13 in RCOG Report 1997-9, 7 of 8 in RCOG Report 2000-2, 2 of 3

in 1994-6 Australian Report). Hyperemesis, haemorrhage, surgery, ectopic and

hyperstimulation after fertility treatment are major risk factors.

Two LMWHs are widely used in pregnant women enoxaparine (Clexane) and dalteparine

(Fragmin). Clexane has been chosen in this Procedure since it is the favoured LMWH for

post-operative.

Low dose unfractionated heparin (UH) and LMWH are equally effective in TP but LMWH

has the advantages of :-

Longer half-life allowing once-daily administration

Less bleeding problems

Less thrombocytopenia

Less osteoporosis if used long-term

The risk of heparin-induced thrombocytopenia is extremely low with LMWH and has never

been reported in pregnancy (RCOG 2004). Current guidelines still recommend checking

platelet levels.


7/10

7

Caesarean wound haematoma is about 2% with both LMWH and unfractionated heparin

(Greer 2001).

Misdiagnosis of VTE is extremely common all pregnant women with leg and / or chest

symptoms need to be considered as possibly having VTE.

A normal D-dimer result has a high negative predictive value, while an elevated result can

be due to pregnancy alone and therefore has a lower positive predictive value c.f. the non-

pregnant woman.

None of the following is contraindicated in pregnancy

chest xray

V/Q scan

limited venogram

IPC can be made available for prolonged antenatal or postnatal use by contacting B6a.

Below-knee IPC is thought to be as effective as full length IPC (Vanek 1998, Morris 2004)

The data supporting IPC in significant prevention of VTE relate only to use commenced

intraoperative and continued without a break for at least several (about 5) days

postoperatively (Clarke-Pearson 1993)

There is little or no data supporting efficacy of IPC used only intraoperative or even

continued for 24 hours post-op (Clarke-Pearson 1984). However, many thrombi are known

to begin intraoperative and IPC has rare or no morbidity. It should therefore be used

intraoperative in all pregnant women.

GCS exert gradually diminishing pressure up the leg, with the commonly available brands

exerting approximately 10-18 mmHg at the ankle, 8-14mmHg at the calf and 6-12mmHg atthe thigh. This is to be distinguished from the higher pressure gradients found in the

considerably more expensive compression stockings used by patients with venous / valve

insufficiency.

There is conflicting evidence as to whether GCS enhance the effectiveness of IPC. Until

the matter is clarified, women under our care will not usually be given both.

While there is little comparative data (Byrne 2001, Amarigiri 2004), below knee GCS are

probably as effective as thigh-length. They are certainly more comfortable, less likely to

wrinkle / band, and less likely to become soiled. As a result, compliance is greater.

COST- EFFECTIVENESS OF PROCEDURE

There are no data available on the cost-effectiveness of TP in pregnant women, but there is

extensive data that confirms the cost-effectiveness of TP in surgical and critical-care

patients.

Since the maternal death rate is only just over 1 per 1000,000 pregnancies, and since at

least 25% of postnatal women will require prophylaxis, the dollar and time-cost of saving

one life is likely to be considerable.

On the other hand, the rate of non-fatal clinical VTE is about 1 per 1000 pregnant women

with subclinical VTE likely to be considerably more common.


8/10

8

As well, the maternal death rate from VTE currently exceeds that from

hypertension/eclampsia and yet much greater resources are devoted to managing the

latter.

The consequences of VTE include not only fatal PE, but also:-

o Delayed discharge from hospital or requiring readmission

o Costly diagnostic testing

o Complications from anti-coagulant therapy

o Recurrent VTE

o Pulmonary hypertension in 5% after PE

o Long-term morbidity from post-thrombotic syndrome with persistent occlusion of

valvular/venous incompetence developing in 80% after DVT (severe in 10%)

causing:-

Chronic leg swelling

Leg ulcers

Pain

Loss of mobility

Loss of income

(Berquist 1990, Kearon 2003, Geerts 2004)

COSTS

o Clexane = $4.50 per preloaded 40mg syringe

o GCS = $5.70 per pair

o IPC sleeves = $60 per pair average (range $50 - $105).


9/10

9

ATTACHMENT 3.

References:-Amaragiri SV, Lees TA. Elastic compression stockings for prevention of DVT. CochraneReview. The Cochrane Library 2004, Issue 2.

Bergqvist A. Late symptoms after pregnancy-related deep vein thrombosis BJOG 1990;

97:338-341

Byrne B. DVT prophylaxis: the effectiveness and implications of using below-knee or thigh-length graduated compression stockings. Heart And LungJuly-August 2001; 30(4):277-284

Clarke-Pearson DL, Creasman WT et al. Perioperative external pneumatic calfcompression as thromboembolism prophylaxis in gynecology: report of randomisedcontrolled trial. Gynecol Oncol1984; 18: 226-32

Clarke-Pearson DL et al. A randomised trial of low-dose heparin and intermittentpneumatic calf compression for the prevention of DVT after gynaecologic oncologysurgery. AmJOG April 1993;168(4):1146-54

Doyle NM, Monga M. Thromboembolic disease in pregnancy. O & G Clinics N.Am2004;31:319-344.

Gates S, Brocklehurst P, Davis LJ. Prophylaxis for VTE in pregnancy and early postnatalperiod. Cochrane Review. The Cochrane Library 2004, Issue 2.

Geerts WH et al. Prevention of venous thromboembolism: the seventh American College

of Chest Physicians conference on antithrombotic and thrombolytic therapy. ChestSeptember 2004;126:338S-400S.

Greer IA. The acute management of venous thromboembolism in pregnancy.CurrOpO&G Dec 2001; 13(6):569-575

Kearon D. Natural history of VTE. Circulation June 17 2003;107(23) Supplement:I-22 to I-30

Maternal Mortality UK 1997-9. Why mothers die. (www.cemach.org.uk/publications)

Maternal Mortality UK 2000-2. Why mothers die. (www.cemach.org.uk/publications)

Maternal Mortality Australia 1994-6. (www.nhmrc.gov.au/publications)

Morris, RJ. Evidence-based compression: prevention of stasis and deep vein thrombosis.Annals Of Surgery February 2004;239(2):162-171

RCOG 2004, January. Thromboprophylaxis during pregnancy, labour and after vaginaldelivery Guideline No. 37 (www.rcog.org.uk)

RCOG 2001, April. Thromboembolic disease in pregnancy and the puerperium: acutemanagement. Clinical Green Top Guideline (www.rcog.org.uk)
http://www.cemach.org.uk/publicationshttp://www.cemach.org.uk/publicationshttp://www.cemach.org.uk/publicationshttp://www.cemach.org.uk/publicationshttp://www.cemach.org.uk/publicationshttp://www.cemach.org.uk/publicationshttp://www.nhmrc.gov.au/publicationshttp://www.nhmrc.gov.au/publicationshttp://www.nhmrc.gov.au/publicationshttp://www.rcog.org.uk/http://www.rcog.org.uk/http://www.rcog.org.uk/http://www.rcog.org.uk/http://www.rcog.org.uk/http://www.rcog.org.uk/http://www.rcog.org.uk/http://www.rcog.org.uk/http://www.nhmrc.gov.au/publicationshttp://www.cemach.org.uk/publicationshttp://www.cemach.org.uk/publications


10/10

10

RCOG 1995. Report of working party on prophylaxis against VTE in O & G. (Obtained viaRCOG library from Elaine [email protected])

Vanek VW. Meta-analysis of effectiveness of intermittent pneumatic compression deviceswith a comparison of thigh-high to knee-high sleeves AmSurg1998;64(11):1050-8.

White RH. The epidemiology of VTE. Circulation June 17, 2003;107(23) Supplement. I-4to I-8.
mailto:[email protected]:[email protected]:[email protected]:[email protected]

Documents

Postnatal Thromboprophylaxis