SIPHRE Shock Index in Pregnancy: Haemorrhage Risk Evaluation. Shock index as a predictor of adverse outcome in maternal haemorrhage

每天有800名妇女死于怀孕和分娩，其中99%发生在中低收入国家。如果不及时发现和处理，出血可在几小时内导致死亡，是全球孕产妇死亡的主要原因。早期发现和有效管理依赖于监测生命体征，包括心率和血压。我们有有效的管理，以防止因出血死亡，但大多数死亡或严重的发病率发生，因为延误或不合格的治疗，在诊断和管理;在许多中低收入国家（LMIC），由于缺乏工作人员/设备或设备运行不良，我们的项目是一项生命体征比率的验证研究，称为休克指数（SI）-一个简单的计算使用心率除以血压。我们以前在妊娠和出血中对SI的研究表明，这是识别受损患者的一种上级方法。由于SI易于测量，易于应用于日常实践，我们希望证明它是早期识别出血患者预后不良（大手术，大失血或死亡）的有效工具，旨在降低LMIC的孕产妇死亡率和发病率。CRADLE VSA（CVSA）设备可准确测量血压和心率，并将结果显示在屏幕上。它显示了与休克指数阈值一致的红色/琥珀色/绿色交通灯警告系统，以提醒用户患者的风险危害，从而允许即使是未经培训的卫生工作者也能迅速转诊或升级管理。CVSA设备经过我们团队15年的设计和广泛验证，成为最便宜，最准确的设备，可以测量我们在怀孕期间看到的高血压和低血压。它被公认为全球健康领域30大影响力创新之一。它已经被开发用于LMIC，重量轻，价格便宜，坚固耐用，易于使用。在CRADLE 3试验中对CVSA的使用进行了广泛研究。塞拉利昂的国家数据显示，该计划的实施使孕产妇死亡率降低了60%（RR 0.37 CI 0.25 - 0.550）。在成功之后，塞拉利昂卫生部目前正在全国范围内推广CRADLE VSA设备，由DIFD，WHO，UNICEF和JICA提供支持。我们提出了一项关于塞拉利昂休克指数的前瞻性验证研究，在塞拉利昂，不良后果非常普遍，以获得大量数据来支持SI作为早期识别出血母亲妥协的工具。SL拥有世界上最高的死亡率（每100，000名活产婴儿中有1，165人死亡）。在英国，这是每10万人中有9人）。将收集所有发生出血（失血量超过500 ml）的妊娠/产后女性的数据，包括首次和最差生命体征以及临床结局。将评价休克指数预测不良临床结局的性能，并与现有生命体征评分进行比较。LMIC中没有用于识别受损患者的标准化早期预警系统。在对SI进行验证后，我们提出了一项试验，以评估SI在LIC出血患者的分诊和管理中的作用。预计将SI作为分诊/转诊标准的护理包将改善护理。由于可避免的孕产妇死亡和未遂事件通常与血流动力学损害的识别延迟有关，因此这种简单的自动预警系统可用于世界各地的LIC。

800 women die in pregnancy and childbirth each day, 99% of these occur in low-middle income countries (LMICs). Haemorrhage can cause death within a few hours if not recognised and managed quickly and is the leading cause of maternal death worldwide. Early detection and effective management rely on monitoring of vital signs , including heart rate and blood pressure. We have effective management to prevent death from bleeding, but most deaths or severe morbidities occur because of delayed or substandard care in the diagnosis and management; in many low- middle income countries (LMIC) vital signs are not measured due to lack of staff/ equipment or poorly functioning devices, leaving the recognition of compromised patients to crude visual estimation of blood loss alone or late signs such as collapse.Our project is a validation study of a vital signs ratio called shock index (SI)- a simple calculation using heart rate divided by blood pressure. Our previous work on SI in pregnancy and haemorrhage suggests it is a superior way of recognising compromised patients. Since SI is simple to measure and easy to apply to daily practice, we hope to demonstrate it is an effective tool for early recognition of bleeding patients at risk of poor outcome (major surgery, major blood loss or death) with the aim to reduce maternal mortality and morbidity in LMIC. The CRADLE VSA (CVSA) device accurately measures blood pressure and heart rate, displaying the results on a screen. It shows a red/amber/green traffic light warning system consistent with shock index thresholds to alert users to the patient's risk compromise, thus allowing prompt referral or escalation of management by even untrained health workers. The CVSA device has been designed and extensively validated by our team over 15 years to become the cheapest and most accurate device to measure BP at the high and low range we see in pregnancy. It is recognised as one of the top thirty high impact innovations in global health. It has been developed for use in LMIC being light, inexpensive, robust and easy to use. The use of the CVSA was extensively researched in the CRADLE 3 trial. In country data from Sierra Leone (SL) showed its implementation reduced maternal death rate by 60% (RR 0.37 CI 0.25 to 0.550). Following its success, the Department of Health in Sierra Leone are now rolling out the CRADLE VSA device nationwide, supported by DIFD, WHO, UNICEF and JICA.We propose a prospective validation study of shock index in Sierra Leone, where adverse outcomes are so prevalent, in order to obtain large data to support SI as a tool for earlier recognition of compromise in bleeding mothers. SL has the world's highest mortality rate (1,165 deaths per 100,000 live births. In the UK this is 9 per 100,000). Data including first and worst vital signs and clinical outcomes will be collected on all pregnant/postpartum women who suffer with haemorrhage (blood loss over 500mls). The performance of shock index to predict adverse clinical outcomes will be evaluated and compared to existing vital signs scores. A standardised early warning system for recognition of compromised patients does not exist for use in LMIC. Following validation on SI we propose a trial to evaluate the effect of SI in triage and management of bleeding patients in LIC. It is anticipated that a care bundle that incorporates SI as a triage/referral criteria will improve care. Since avoidable maternal deaths and near-misses are often related to delays in recognition of hemodynamic compromise this simple automated early warning system could be used in LIC worldwide.