Dr Claire McLintock
Auckland DHB
Dr Claire McLintock MBChB (Edin) FRACP, FRCPA is an obstetric physician and haematologist at National Women’s Health, Auckland City Hospital where she is Clinical Director of Regional Maternity Services including obstetric medicine and maternal fetal medicine. She has a special interest in haematological problems in pregnancy, with particular interests in venous thromboembolism, thrombocytopenia, preeclampsia, maternal morbidity and mortality, obstetric haemorrhage and management of anticoagulation in pregnant women with mechanical heart valves.


Claire is a Council member and President-elect of the International Society on Thrombosis and Haemostasis and is Chair of its Education and Outreach Committee and its Membership & Communication Subcommittee. She is a member of the Steering Committee for ISTH World Thrombosis Day. She is a past-President of the Australasian Society of Thrombosis and Haemostasis and of the Society of Obstetric Medicine of Australia and New Zealand.

She is active in clinical research and is Co-Principle Investigator of the EPPI study assessing the impact of enoxaparin on the risk of recurrent early onset preeclampsia and intrauterine growth restriction, she is a member of the steering committee for an Australasian NHMRC funded registry for Massive Transfusion. She is lead investigator of the FibUpFront PPH study that aims to determine if early administration of fibrinogen concentrate improves outcomes in severe PPH. She leads the NZ branch of the Australasian Maternity Outcomes Surveillance System looking at severe maternal morbidity in complications including antenatal pulmonary embolism, peripartum hysterectomy, amniotic fluid embolism, eclampsia, rheumatic heart disease, massive transfusion in obstetrics, and placenta accreta.

ABSTRACT

Management of Postpartum Haemorrhage: a Haematologist’s View
Dr Claire McLintock. Haematologist & Obstetric Physician, Service Clinical Director, Regional Maternity Services, Women’s Health, Auckland City Hospital.

Postpartum haemorrhage (PPH) is a major global cause of maternal mortality and morbidity. Attempts to minimize the clinical impact of PPH include primary prevention with measures to increase the awareness of women who are at risk from PPH, but most women with major PPH do not have identifiable risk factors. Minimising adverse outcomes includes ensuring a rapid recognition and response to postpartum bleeding with education emphasizing the importance of early transfer and escalation of care to secondary or tertiary centres for women who do not respond to initial measures. A coordinated response for women with uncontrolled bleeding includes the use of effective uterotonic agents, transfusion with blood and plasma products to maintain circulating blood volume and tissue oxygenation and correct coagulopathy; obstetric assessment for problems such as retained placenta, genital tract trauma and interventions such as balloon tamponade, uterine artery embolization and hysterectomy.

A critical feature of obstetric haemorrhage is development of coagulopathy, particularly early-onset coagulopathy that develops even before massive transfusion causes haemodilution. Early consumption of fibrinogen followed by hyperfibrinolysis is a feature of obstetric complications such as placental abruption, amniotic fluid embolism and retained fetus after intrauterine demise but even in PPH not due to these conditions early consumption of fibrinogen is described. Studies have shown that when PPH is diagnosed, women with lower mean levels of fibrinogen go onto develop more severe haemorrhage. These hypothesis-generating observational studies support the association of a low fibrinogen concentration with development of more severe haemorrhage. They do not answer the important question as to whether early replacement of fibrinogen will modify the risk of severe haemorrhage developing subsequently. A recently published study by the Danish group: FibPPH (Pre-emptive treatment with fibrinogen concentrate for postpartum haemorrhage: randomized controlled trial) by Wikkelso et al demonstrated no benefit in terms of the reduction of transfusion of red blood cells in women who have a normal fibrinogen at the time of bleeding. The mean fibrinogen concentration at time of enrolment was 4.5g/L with a range of 3.2 – 5.8 g/L; none of the women in the study had a fibrinogen under 3g/L. We know from other studies that fibrinogen less than 3.2g/L is a predictor of the severity of PPH and in trauma and cardiothoracic surgery low fibrinogen of less than 2g/L is associated with more severe bleeding.

The approach to management of obstetric haemorrhage involves immediate resuscitation with fluid to maintain circulating blood volume, with rapid recourse to transfusion of red blood cells to maintain tissue oxygenation. At the same time an obstetric survey is required to identify and treat the cause of bleeding, which in the majority of cases will be due to uterine atony, with retained placenta and genital tract trauma remaining important causes. Coagulopathy frequently occurs early in the setting of PPH and urgent bloods should be taken for standard coagulation studies, which are increasingly being supplemented by point-of-care testing using thromboelastography TEG or ROTEM.

Rheumatic Heart Disease in Pregnancy: cardiac outcome in the New Zealand AMOSS cohort

Authors: C McLintock1, F Mahony1, B Peat2, A Coverdale1, M Wheeler1, A Ekeroma2, W Harrison2

Affiliation: 1=Auckland District health Board, Auckland, New Zealand, 2 = Counties Manukau District Health Board, Auckland, New Zealand

Background: The Australasian Maternity Outcomes Surveillance System (AMOSS) studies a variety of uncommon serious obstetric conditions aiming to improve the safety and quality of maternity care in Australia and New Zealand.  Rheumatic heart disease (RHD) is one condition studied by AMOSS.

Aim: Determine the prevalence and severity of RHD in women in NZ to assess the rate and type of cardiac complications in this cohort.

Methodology: Observational prospective cohort study of pregnant women with RHD in NZ (data collection 1/10/2012-31/12/2014). Data sources: Perinatal and Maternal Mortality Review Committee’s Local Coordinators, Lead Maternity Carers, Cardiologists, Obstetric Physicians and District Health Board coding.  Data collection and data entry completed by national RHD coordinator.  

Results: 130 women were identified who had 147 pregnancies. The median age was 27 years and their ethnicity was Maori 40% (n=64), Pacifica 54% (n=74) and other  6% (n=7). Eighty-two (63%) women lived in the greater Auckland region. Women with RHD numbered about 1 in 200 of all Pacifica women and 1 in 500 Maori women who gave birth over the period compared to 1 in 15,000 NZ European women. Cardiac complications developed in 24 women (15.6%), 79% (n=19) with severe RHD and 21% (n=5) with non-severe RHD. Of the 41 (28%) women with echocardiographic features consistent with severe RHD, 41% (n=19) developed cardiac complications in pregnancy. Women who developed cardiac complications were asymptomatic at the beginning of pregnancy. There were no maternal deaths.

Conclusion: This study suggests that clinical symptoms alone are unhelpful in indentifying which women with a history of RHD need high-risk care and emphasises the importance echocardiographic assessment of these women. The high prevalence of RHD in high-risk populations suggests a potential role for screening Maori and Pacific in pregnancy for unrecognsied RHD.