Incidence of postpartum haemorrhage defined by quantitative blood loss measurement: a national cohort

Background Visual estimation of blood loss following delivery often under-reports actual bleed volume. To improve accuracy, quantitative blood loss measurement was introduced for all births in the 12 hospitals providing maternity care in Wales. This intervention was incorporated into a quality improvement programme (Obstetric Bleeding Strategy for Wales, OBS Cymru). We report the incidence of postpartum haemorrhage in Wales over a 1-year period using quantitative measurement. Methods This prospective, consecutive cohort included all 31,341 women giving birth in Wales in 2017. Standardised training was cascaded to maternity staff in all 12 hospitals in Wales. The training comprised mock-scenarios, a video and team drills. Uptake of quantitative blood loss measurement was audited at each centre. Data on postpartum haemorrhage of > 1000 mL were collected and analysed according to mode of delivery. Data on blood loss for all maternities was from the NHS Wales Informatics Service. Results Biannual audit data demonstrated an increase in quantitative measurement from 52.1 to 87.8% (P  1000 mL, > 1500 mL and > 2000 mL was 8.6% (8.3 to 8.9), 3.3% (3.1 to 3.5) and 1.3% (1.2 to 1.4), respectively compared to 5%, 2% and 0.8% in the year before OBS Cymru. The incidence (95% CI) of bleeds of > 1000 mL was similar across the 12 hospitals despite widely varied size, staffing levels and case mix, median (25th to 75th centile) 8.6% (7.8–9.6). The incidence of PPH varied with mode of delivery and was mean (95% CI) 4.9% (4.6–5.2) for unassisted vaginal deliveries, 18.4 (17.1–19.8) for instrumental vaginal deliveries, 8.5 (7.7–9.4) for elective caesarean section and 19.8 (18.6–21.0) for non-elective caesarean sections. Conclusions Quantitative measurement of blood loss is feasible in all hospitals providing maternity care and is associated with detection of higher rates of postpartum haemorrhage. These results have implications for the definition of abnormal blood loss after childbirth and for management and research of postpartum haemorrhage

Reduction in massive postpartum haemorrhage and red blood cell transfusion during a national quality improvement project, Obstetric Bleeding Strategy for Wales, OBS Cymru: an observational study

Background Postpartum haemorrhage (PPH) is a major cause of maternal morbidity and mortality and its incidence is increasing in many countries despite management guidelines. A national quality improvement programme called the Obstetric Bleeding Strategy for Wales (OBS Cymru) was introduced in all obstetric units in Wales. The aim was to reduce moderate PPH (1000 mL) progressing to massive PPH (> 2500 mL) and the need for red cell transfusion. Methods A PPH care bundle was introduced into all 12 obstetric units in Wales included all women giving birth in 2017 and 2018 (n = 61,094). The care bundle prompted: universal risk assessment, quantitative measurement of blood loss after all deliveries (as opposed to visual estimation), structured escalation to senior clinicians and point-of-care viscoelastometric-guided early fibrinogen replacement. Data were submitted by each obstetric unit to a national database. Outcome measures were incidence of massive PPH (> 2500 mL) and red cell transfusion. Analysis was performed using linear regression of the all Wales monthly data. Results Uptake of the intervention was good: quantitative blood loss measurement and risk assessment increased to 98.1 and 64.5% of all PPH > 1000 mL, whilst ROTEM use for PPH > 1500 mL increased to 68.2%. Massive PPH decreased by 1.10 (95% CI 0.28 to 1.92) per 1000 maternities per year (P = 0.011). Fewer women progressed from moderate to massive PPH in the last 6 months, 74/1490 (5.0%), than in the first 6 months, 97/1386 (7.0%), (P = 0.021). Units of red cells transfused decreased by 7.4 (95% CI 1.6 to 13.2) per 1000 maternities per year (P = 0.015). Red cells were transfused to 350/15204 (2.3%) and 268/15150 (1.8%) (P = 0.001) in the first and last 6 months, respectively. There was no increase in the number of women with lowest haemoglobin below 80 g/L during this time period. Infusions of fresh frozen plasma fell and there was no increase in the number of women with haemostatic impairment. Conclusions The OBS Cymru care bundle was feasible to implement and associated with progressive, clinically significant improvements in outcomes for PPH across Wales. It is applicable across obstetric units of widely varying size, complexity and staff mixes

Cell-type–specific eQTL of primary melanocytes facilitates identification of melanoma susceptibility genes

Most expression quantitative trait locus (eQTL) studies to date have been performed in heterogeneous tissues as opposed to specific cell types. To better understand the cell-type–specific regulatory landscape of human melanocytes, which give rise to melanoma but account for <5% of typical human skin biopsies, we performed an eQTL analysis in primary melanocyte cultures from 106 newborn males. We identified 597,335 cis-eQTL SNPs prior to linkage disequilibrium (LD) pruning and 4997 eGenes (FDR < 0.05). Melanocyte eQTLs differed considerably from those identified in the 44 GTEx tissue types, including skin. Over a third of melanocyte eGenes, including key genes in melanin synthesis pathways, were unique to melanocytes compared to those of GTEx skin tissues or TCGA melanomas. The melanocyte data set also identified trans-eQTLs, including those connecting a pigmentation-associated functional SNP with four genes, likely through cis-regulation of IRF4. Melanocyte eQTLs are enriched in cis-regulatory signatures found in melanocytes as well as in melanoma-associated variants identified through genome-wide association studies. Melanocyte eQTLs also colocalized with melanoma GWAS variants in five known loci. Finally, a transcriptome-wide association study using melanocyte eQTLs uncovered four novel susceptibility loci, where imputed expression levels of five genes (ZFP90, HEBP1, MSC, CBWD1, and RP11-383H13.1) were associated with melanoma at genome-wide significant P-values. Our data highlight the utility of lineage-specific eQTL resources for annotating GWAS findings, and present a robust database for genomic research of melanoma risk and melanocyte biology

Developing low-cost intelligent wireless sensor networks for aquatic environments

Aquatic environments are extremely difficult for developing, deploying, and maintaining wireless sensor networks. Networks deployed in aquatic settings face multiple challenges, such as marine fowling of equipment, limited power supply, communications difficulties, and \ud restricted accessibility for maintaining and updating sensor nodes. The SEMAT project is an initiative to create "smart", low-cost, heterogeneous wireless sensor networks, tailored to alleviating the aforementioned constraints. Networks can be instantly deployable with minimal setup overheads and can utilise equipment from multiple vendors. This paper presents our experiences with developing the initial technologies to establish SEMAT for field tests. We present the design methodology and challenges faced for creating a marine-based heterogeneous wireless sensor network platform. The result is a low cost solution, with sufficient accuracy for undertaking a study into the factors contributing to Lyngbya algae blooms in Deception Bay, Queensland. The platform builds a case for the merits of the final SEMAT system, as ultimately many of the software and basic hardware challenges for future aquatic deployments have been overcome. This is significant as it allows researchers to focus on the area under study, rather than the specifics of setting up and managing the network

Overcoming the technical problems associated with effective coastal monitoring systems

Coastal and aquatic ecosystems contain a wealth of information that is largely untapped. Understanding the complex dynamics of marine environments will enable scientists to propose sound methods for how to better manage these valuable resources in a sustainable manner. Emerging wireless sensor network technologies are now providing marine scientists with tools to gather data on key ecological factors in ways never previously thought possible. However, various technical, commercial, and logistical factors make it difficult to effectively develop and utilize coastal monitoring technology. This paper examines the main issues associated with wireless sensor network technologies for use in coastal monitoring applications. It describes the challenges faced by the developers, the conflicting push and pull influences by vendors, and the logistical/operational issues for deploying sensor networks in harsh marine environments. We describe the lesions learnt from several real-world sensor network systems currently in use on the Great Barrier Reef, Deception Bay and Heron Island. The experience gained from these deployments can be used as a blue print for future coastal monitoring applications so that cheaper, more cost effective, and user-friendly systems will result. This will enable end users to better understand the sensitive ecological factors that effect these environments, without being burdened by the underlying technical detail

Benefits of building wireless sensor networks on commodity hardware and software stacks

The majority of wireless sensor networks are built on bespoke platforms, that is, custom designed and built hardware with a light weight software stack. There are a number of advantages to this approach. First, the ability to closely match and minimise the resource requirements (e.g., power consumption and communications protocols) to those that are suitable for the intended deployment. Second, as an entire hardware and software stack is often designed or at least optimised for each deployment, the latest advances can be quickly incorporated. However, this model generally requires the expertise of hardware and software engineers to design and build the system. In turn, this increases the cost and tends to shift the focus away from the initial science towards the development of the wireless sensor networks. This paper explores the utility and practicality of building wireless sensor networks based on commercially available embedded single board computing platforms using standard consumer operating systems. Our test bed was built using Gumstix computing platform, running a Linux Operating System (OS) with a java-based middleware coupled to low-cost scientific grade sensors. Test deployments have found this to be a highly versatile solution, able to leverage the flexibility of commodity hardware and software while maintaining reasonable utility

Real time data streaming in sensor networks: integrating SAL with the RBNB Data Turbine

Developing a large sensor-based observation system faces two serious challenges: 1) incompatible sensor technologies from different manufacturers; and 2) complexity of the data streaming process. Sensor Abstraction Layer (SAL) is a middleware integration platform which enables a single interface to view and control heterogeneous sensors regardless of the technologies involved. Although SAL addresses the software compatibility issue of sensors from different manufacturers, it provides limited support for real-time visualisation of the sensed data. Real-time data streaming is extremely useful for scientific modelling and presenting study results for which the sensor network has been designed to investigate. This limitation of SAL can be improved through using existing purpose-built technologies such as the Ring Buffer Network Bus Data Turbine. The Data Turbine is an open-source data management system which provides services for data stream management, routing, monitoring and visualisation. This paper introduces SAL-T (Transmission) which integrates SAL with the Data Turbine. SAL-T is an extra software layer that facilitates the management of the sensed data from SAL into the Data Turbine. Performance tests have been conducted using SAL-T in a simulated data streaming environment indicative of a wireless sensor network. The tests showed that SAL-T dramatically reduced network traffic and improved transmission times