Prevention of vte

25
PREVENTION OF VTE IN OBSTETRIC POPULATION BY Dr Kanddy Loo O&G Updates 1/11/14 O&G department Miri hospital

Transcript of Prevention of vte

Page 1: Prevention of vte

PREVENTION OF VTE IN OBSTETRIC POPULATIONBY Dr Kanddy Loo

O&G Updates

1/11/14

O&G department

Miri hospital

Page 2: Prevention of vte

CASE SCENARIO

• 40 year-old P6, post emergency caesarean sectionfor acute fetal distress D 6

• Had BMI of 40

• Presented with acute onset of SOB and chest pain

• Denied calf swelling

• Otherwise, no known medical illness; normotensive antenatally and intrapartumly

• Examination showed tachycardia and tachypnoea; with saturation under room air of 80%; normotensive

• Lungs examination was unremarkable

Page 3: Prevention of vte

PROBABLE DIAGNOSIS…..

Page 4: Prevention of vte

INTRODUCTION

• Pulmonary embolism remains the leading direct cause of maternal death

• Most of the patients who died from PE have identifiable risks• 70% of women who died from PE in UK between 2003-2005 had identifiable risk

• Thromboprophylaxis antenatally and postnatally – estimated to reduce risk of VTE in obstetric patients by up to 2/3

• Objective of this lecture• Introduction of state VTE prevention programme• Risk stratification of patient according to VTE score to identify patients for

thromboprophylaxis

• Antenatal VTE occur in the first trimester • Therefore assessment and prophylaxis, if indicated should be given as early as possible

in pregnancy

Page 5: Prevention of vte

MATERNAL MORTALITY - UK

CEMACH 2003-2005 CEMACH 2006-2008

Page 6: Prevention of vte

MATERNAL MORTALITY - MALAYSIA

Page 7: Prevention of vte

PATHOPHYSIOLOGY

• Incidence of VTE in pregnancy – 60/100000 woman-years

• 12 fold increase compared to non pregnant population

• Virchow’s Triad

Page 8: Prevention of vte
Page 9: Prevention of vte

SARAWAK VTE PREVENTION PROGRAMME

• Introduced on 1 July 2013

• To be implemented over Sarawak state• Initially hospital based• Expanded to primary health care centre on Mac 2014

• Obstetric patients are assessed based on modified VTE scoring system• Done as early in pregnancy as possible• Repeat assessment if there’s emergence of new risk factors/during hospitalisation

• Start thromboprophylaxis if• VTE score 3 or more antenatally and continue postnatally for 6 weeks• VTE score 2 or more postnatally – for at least 1 week• Patient with additional persistent risk factor (lasting more then 1/52 postnatal) should

thromboprophylaxis should be extended for up to 6 weeks or longer

Page 10: Prevention of vte
Page 11: Prevention of vte

VERY HIGH VTE RISK

• Needs antenatal high-dose thromboprophylaxis (high prophylactic – 12 hourly or 75% of treatment dose) antenatally and postnatally 6 weeks

• Very high risk factors

• Recurrent VTE associated with APS

• Patient on long term anticoagulation

• Antithrombin deficiency

Page 12: Prevention of vte

HIGH RISK

• Thromboprophylaxis antenatally and 6 weeks postnatally

• Risk factors

• Previous unprovoked, estrogen related (pregnancy/pills induced), recurrent VTE

• Previous VTE with risk factors (family history of VTE, thrombophyilia or other risk factors

• Asymptomatic thrombophilia (combine defects, homozygous Factor V Leiden)

• Combination of 3 or more risk factors

Page 13: Prevention of vte

INTERMEDIATE RISK

• Postnatal thromboprophylaxis (duration ranges from 1 – 6 weeks)

• Single previous VTE associated with temporary risk factor with no other risk factors (thromboprophylaxis upto 6 weeks postnatal)

• Asymptomatic thrombophilia (except antithrombin deficiency, combined defects, homozygous FVL) – 1 week prophylaxis or 6 weeks if presence of other risk factors

• Presence of 2 or more risk factors

Page 14: Prevention of vte

THROMBOPHILIA SCREENING

• Only done for those VTE provoked by minor risk factors

• Antenatal thromboprophylaxis till postnatal 6/52

• Previous VTE with thromphilia

• Asymptomatic thrombophilia with other risk factors

• Asymptomatic thrombophilia

• Combine defects

• Homozygous Factor V Leiden

• Postnatal thrombophylaxis

• Other asymptomatic thrombophilia without other risk factors

Page 15: Prevention of vte

ANTI COAGULANT AGENTS

• Low molecular weight heparin

• Agents of choice

• As effective as and safer then the unfractionated heparin

• Lower risk of Heparin induced thrombocytopaenia and osteoporosis

• Risk of bleeding - <2% with prophylactic dose

• Monitoring of anti-Xa levers is not required if women have normal renal function

• Unfractionated Heparin

• Shorter half life

• More complete reversal of its activity

• May be used around the time of delivery in women with very high risk of thrombosis

Page 16: Prevention of vte

• Fondaparinox• Licenced for prevention and treatment of VTE outside pregnancy• Similar efficacy to LMWH• Limited experience in pregnancy

• Although no adverse effects were observed in newborns, it is premature to conclude its safety in pregnancy• Reserved for women intolerance to heparin• Local setting – used in postnatal thrombophylaxis

• Warfarin• Associated with warfarin embriopathy

• 5% risk when exposed between 6 – 12 weeks• For patient with mechanical heart valve• Can be used postnatally – 5 – 7 days post delivery• Safe in breastfeeding

• Other anti coagulant – avoided in pregnancy

• Graduated elastic compression stocking

Page 17: Prevention of vte
Page 18: Prevention of vte

CONTRAINDICATION TO THROMBOPROPHYLAXIS

• Antenatal or postpartum bleeding

• Massive PPH – risk factor for VTE; therefore risk and benefits of thromboprophylaxisshould be weighted

• Increased risk of major haemorrhage

• Bleeding diathesis, including thrombocytopaenia

• Platelet less than 75 x 109

• Acute stroke in last 4 weeks

• Severe renal disease

• Severe liver disease

• Uncontrolled hypertension (SBP>200mmHg; DBP>120mmHg)

Page 19: Prevention of vte

ANAESTHESIA

• Regional techniques should not be used at least 12 hours after previous prophylactic dose of LMWH

• 24 hours after last dose of therapeutic dose

• 4 hours after last dose of unfractionated heparin

• LMWH should not be given for 4 hours after regional anaesthesia or after removal of epidural catheter

• Epidural catheter should not be removed within 10 – 12 hours of the last dose

Page 20: Prevention of vte

QUIZ – SCENARIO 1

• 40 year-old; primigravida; subfertility for 20 years

• BMI 32

• Currently at 10 weeks…..

Page 21: Prevention of vte

• At 12 weeks, she was admitted with hyperemesis gravidarum….

• At 30 weeks, she was again admitted and treated as acute appendicitis; appendicectomy was done

Page 22: Prevention of vte

• At 38 weeks, she has EMLSCS for fetal compromise; complicated with massive PPH and had massive transfusion….

Page 23: Prevention of vte

QUIZ – SCENARIO 2

• 30 year-old G2P1 at 8 weeks; came for booking

• Previous history of postpartum DVT; completed warfarin treatment for 6 months

• Currently well, no leg swelling

• BM1 25

Page 24: Prevention of vte

• At 36 weeks, she presented with SROM with TMSL and os was only 1 cm….

• Postnatally….

Page 25: Prevention of vte

THANK YOU