Use this URL to cite or link to this record in EThOS: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.664449
Title: Postpartum haemorrhage : new insights from published trials and the development of novel management options
Author: Aflaifel, Nasreen
ISNI:       0000 0004 5363 7064
Awarding Body: University of Liverpool
Current Institution: University of Liverpool
Date of Award: 2015
Availability of Full Text:
Access from EThOS:
Access from Institution:
Abstract:
Postpartum haemorrhage (PPH) is the most common cause of maternal mortality leading to an estimated 86, 000 deaths/year. The most common cause of PPH is failure of the uterus to contract properly (uterine atony). Several measures have been introduced to prevent and treat atonic PPH, but in spite of active management of the third stage of labour (AMTSL), maternal deaths from PPH still occur. PPH can kill rapidly within two hours or less. PPH has long been recognised as a dangerous complication for mothers. In order to optimise the prevention and treatment of PPH, different approaches have been introduced and modified over the last century. We reviewed the regimes used in the management of the third stage of labour between 1917 and 2011 as described in the successive editions of the ‘Ten Teachers’ books. Throughout the Ten Teachers series, uterotonic drugs have always been taught as being the best initial measure to manage PPH. However, the importance of bimanual uterine compression (BMC) has increased gradually, moving from third to first treatment option over the editions (Aflaifel and Weeks, 2012a). The components of the AMTSL package for PPH prophylaxis have recently been extensively examined in clinical trials. Its effectiveness in reducing blood loss is now known to be almost all due to the uterotonics (Aflaifel and Weeks, 2012b). However, clinical trials evaluating the efficacy of uterotonics in treating PPH are comparatively rare. Where present they usually compare two uterotonics with an absence of control group, as it is unethical to leave a bleeding woman untreated. A recent innovation is to model the likely outcomes in the absence of uterotonic therapy through histograms. This also allows an assessment of the efficiency of treatment by measuring the number of women who stop bleeding shortly after administering treatments. This model has never previously been applied to databases in which uterotonics were used for prophylaxis. In a secondary analysis of 4 large randomised trials, small secondary histogram peaks (primarily attributed to a treatment effect) were still present even if uterotonic therapy had not been used. Furthermore, the study revealed that women were commonly treated at low levels of blood loss (< 500 mls). It was also seen that, of those diagnosed with PPH (≥ 500 mls), most stopped bleeding at blood losses of around 700 mls even if they did not receive any uterotonic therapy. This should warn against ascribing all the effect to uterotonic therapy. As well as stopping spontaneously, other physical therapies may also have been used concurrently and may have had an effect. The evidence from the histogram study suggested that use of additional uterotonic is not a good surrogate for PPH in the research context. Chapter 4 reports on evaluations of the outcomes that are used by researchers in PPH trials. In the 121 studies evaluated, there was a huge diversity in choosing the outcomes (PPH prevention). The most common was ‘Incidence of PPH ≥ 500 mls’, which was mentioned in 21% (25/121) of trials. The study interestingly showed that use of additional uterotonic was used for sample size calculation in 6% (7/121) of studies as a surrogate for PPH. The above findings emphasise the importance of physical measures in the early treatment of PPH. BMC is thought to help in treating PPH, although there are no clinical trials on its effectiveness. A survey was therefore conducted amongst obstetric care providers in the UK to look at the frequency of BMC use in clinical practice and the attitudes towards its use. The survey found that, although clinicians find BMC effective, it is rarely used as the procedure is considered to be too tiring and too invasive. If, however, BMC could be performed in a less invasive manner, then it could act as an effective low-cost treatment for those PPHs arising from atony. The thesis concludes with an investigation into a new low cost intervention that might contribute to the early physical management of PPH. The ‘PPH Butterfly’ is a new device that is designed to make uterine compression simpler, less tiring and less invasive. It was compared to the standard BMC in a mannequin model. The main objective was to compare the efficacy of the PPH Butterfly to standard BMC in producing sustained uterine compression. The study revealed that the PPH Butterfly is simple to use on a mannequin model, even among obstetric care providers with little experience. It produces an equivalent amount of pressure to BMC, but neither method produced sustained compression over the 5 minutes of use. It also demonstrates the feasibility of using a mannequin model for teaching and performing BMC.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.664449  DOI: Not available
Keywords: RG Gynecology and obstetrics
Share: