Pregnant women and pregnant people could suffer a potentially fatal blood vessel blockage if their risk is not properly assessed during pregnancy and the first six weeks after birth, says HSIB’s latest report.
The report charts a national investigation that has explored the assessment of risk factors for what is known as a venous thrombosis (VT). A VT occurs when a blood clot forms and causes a blockage in a person’s vein. This can lead to venous thromboembolism (VTE) when the part of the clot breaks off and travels through the bloodstream, blocking a blood vessel elsewhere in the body. Pregnant women and people are at increased risk of developing a VT than those who are of the same age and not pregnant. While rare, a VTE can lead to the death of those who are pregnant and has been cited as a leading direct cause of maternal death.
Risk factors for VTE are routinely assessed at key stages before and after birth, and HSIB specifically focused their investigation on why this existing risk scoring is hard to apply consistently in practice. Their aim was to identify factors that limit the effectiveness of VTE risk assessment policies and identify opportunities to improve patient safety. To highlight the risks and inconsistences, HSIB examined the case of Alice, a 26-year-old woman, who had experienced a pulmonary embolism (PE) 11 days after giving birth to her second child. She had VTE assessments undertaken during and after her pregnancy. She had zero risk factors in her assessment while she was pregnant. However, after her caesarean birth, Alice’s risk assessment score indicated that a preventative dose of a blood-thinning medication would be required. Alice was started on a daily injection of low-molecular-weight heparin and was discharged from hospital. Alice had been prescribed the preventative dose of LMWH based on her weight of 48kg at her initial booking in appointment.
After she was treated for her PE, an investigation (by the hospital) found that Alice may not have received an appropriate preventative dose to help prevent the VTEas her weight after the birth of her baby had increased to 56kg. Preventative doses are different for pregnant women and pregnant people under 50kg and over 50kg. National guidance changed on weight after Alice was discharged from hospital.
HSIB’s investigation found that for healthcare staff, carrying out a robust assessment of risk factors for VTE is challenging, particularly in complex and busy environments. Multiple competing demands, exacerbated by distractions and interruptions, mean healthcare professionals are constantly having to balance risk and safety for the pregnant women/pregnant people they care for and are trading off the thoroughness of assessments to improve efficiency. HSIB also identified that recommendations by MBRRACE-UK (Mothers and Babies: Reducing Risk through Audits and Confidential Enquiries across the UK) for the development of a tool to make the current assessment of VTE risk factors simpler and more reproducible, have not been acted on.
The national investigation identified while there are recommendations for prescribing of medication to thin the blood if a pregnant woman / pregnant person is identified as being at risk, the preventative and treatment dose(s) have not been formally tested in clinical trials. National research studies are ongoing to address identified knowledge gaps within the evidence base, and therefore HSIB haven’t explored this aspect further to avoid duplicating work.
The report concludes with local learning that maternity providers across the country can take on board to help support the assessment of risk factors for VTE. The report also makes safety observations at a national level which are aimed at improving usability of risk assessment tools and the benefits of future research.
Nichola Crust, National Investigator, said: “Our investigation emphasises how important it is that risk assessments for VTE are simple to implement and prioritises those most at risk. From the evidence we gathered, including discussions with NHS staff, it was clear that there are huge challenges and that the time allocated to undertake holistic, individualised risk assessments that meets the needs of the pregnant person is not enough. This is impacted on by workforce challenges, problems with IT and lack of interoperability and competing demands. Where possible, we need to involve pregnant women and pregnant people in these assessments.
“If assessments are not carried out fully, and VTE occurs, the additional treatment needed can cause distress and anxiety at a time when pregnant women and pregnant people may already feel vulnerable. In a small number of cases, the VTE can have a devastating outcome, sadly leading to the death of a soon to be or new mother. The investigation we have carried out adds to the evidence that is already being gathered nationally in this area and offers a crucial perspective on where risk assessments can be improved to ensure the best care during pregnancy and the postnatal period.”