Shock index: an effective predictor of outcome in postpartum haemorrhage?

Maternal mortality due to obstetric hemorrhage by surgical injury during cesarean section: A nationwide study

INTRODUCTION

Obstetric hemorrhage remains a largely preventable cause of maternal mortality globally. The contribution of uterine atony to hemorrhage-related maternal mortality has decreased in France, while the contribution of other causes of obstetric hemorrhage such as surgical injury during cesarean has been reported to increase. However, little evidence exists regarding the risk factors and care processes of women who died from this cause of hemorrhage. Therefore, we aimed to describe the clinical profile, underlying mechanisms, and preventability factors among women who died from obstetric hemorrhage by surgical injury during cesarean section.

MATERIAL AND METHODS

Nationwide analysis of all hemorrhage-related maternal deaths by surgical injury during cesarean in France identified by the nationwide permanent enhanced maternal mortality surveillance system (ENCMM) between 2007 and 2018. We described the characteristics of the women, delivery hospitals, circumstances of hemorrhage, features of obstetric and resuscitation/transfusion care, and main preventability factors.

RESULTS

Between 2007 and 2018, hemorrhage-related maternal mortality in France decreased from 1.6/100 000 live births (95% CI 1.1-2.2) (39/2 472 650) in 2007-2009 to 0.8/100 000 live births (95% CI 0.5-1.3) (19/2 311 783) in 2016-2018. Hemorrhage-related maternal mortality ratio due to surgical injury during cesarean increased from 0.08 (95% CI 0.01-0.3) (2/2 472 650) to 0.2 (95% CI 0.07-0.5) (5/2 311 783) per 100 000 live births. Among the 18 women who died from surgical injury during cesarean over the 12-year study period, we report a high prevalence of obesity (67%, 12/18), previous cesarean (72%, 13/18), and second-stage cesareans (56%, 10/18). In 22% (4/18), cesarean section was performed in a hospital providing <1000 births annually, with no blood bank (39%, 7/18) or no adult intensive care (44%, 8/18) on-site. Overall preventability of deaths was 94% (17/18). Main preventability factors were related to delay in hemorrhage diagnosis (77%, 14/18) due to late recognition of abnormal parameters (33%, 6/18) and late bedside ultrasound (56%, 10/18), and delay in management due to insufficient surgical skills (56%, 10/18).

CONCLUSIONS

In France, surgical injury during cesarean section is an increasing, largely preventable contributor to hemorrhage-related maternal mortality, as other causes of fatal hemorrhage have become less frequent. The profile of these women showed a high prevalence of obesity, previous cesarean, second-stage cesarean, and delivery in hospitals with limited medical and surgical resources, which suggests explanatory mechanisms for the fatal outcome and opportunities for prevention.

Management of maternal pulse and blood pressure abnormalities during labour and childbirth: evidence-based algorithms for intrapartum care decision support

AIMS

To develop evidence-based clinical algorithms for assessment and management of abnormal maternal pulse and blood pressure during the intrapartum period.

POPULATION

Low risk singleton, term, pregnant women in labour.

SETTING

Institutional births in low- and middle-income countries.

SEARCH STRATEGY

A review of the literature was performed to retrieve evidence-based guidelines, systematic reviews, and papers on maternal pulse and blood pressure during labour. We searched a number of international clinical guidelines and PubMed using the corresponding key terms in November 2018 and updated the search in May 2020.

CASE SCENARIOS

Four common intrapartum case scenarios of abnormal pulse and blood pressure were identified for which algorithms were developed: hypertension, hypotension, tachycardia and bradycardia. Algorithms were constructed after reviewing guidelines and relevant papers, with input from a panel of experts. Thresholds for upper and lower limits of normal maternal pulse and blood pressure measurements are defined, evidence-based interventions for the initial management of abnormal parameters are described (resuscitation and monitoring) and guidance is provided on exploration of the potential causes for each case scenario, with links to pathways for their management.

CONCLUSIONS

Evidence-based algorithms to support the identification, and management of deviations in pulse and blood pressure during intrapartum care have been developed for hypertension, hypotension, tachycardia and bradycardia. The algorithms focus on initial resuscitation and monitoring, with an exploration of causes and early identification of underlying maternal conditions. These algorithms will help provide a standardised approach to investigation and management of these abnormal parameters to guide clinical practice.

TWEETABLE ABSTRACT

Algorithms for abnormal maternal pulse and blood pressure during labour allow standardised approach to early identification and management of complications.

TWEETABLE ABSTRACT

Clinical algorithms for management of third stage abnormalities

AIMS

To develop algorithms for identifying, managing and monitoring postpartum haemorrhage (PPH) and other third stage of labour abnormalities after vaginal delivery.

POPULATION

Women with low-risk singleton term pregnancies who have had a vaginal delivery.

SETTING

Hospital settings with a particular focus on healthcare facilities in low- and middle-income countries (LMICs).

SEARCH STRATEGY

Searches for international and national guidance documents, research databases (Cochrane, Medline and CINAHL) and published systematic reviews. Searches were limited to work published in English between 1 January 2008 and 31 December 2018.

CASE SCENARIOS

Four interlinked case scenarios were identified for algorithm development: (1) an approach to PPH after vaginal delivery, (2) uterine atony, (3) genital tract trauma and (4) retained placenta/placental products.

CONCLUSIONS

The development of clear approaches to the assessment, resuscitation, treatment and monitoring of the four case scenarios are presented as algorithms, based on available evidence. They need to be field tested and evaluated for effectiveness, and may be adapted for electronic decision support tools using artificial intelligence in different settings. Further research is needed around multimodal sequential packages of care for PPH, conservative surgical measures, resuscitation in LMICs, and how a respectful maternity care focus can be incorporated into the algorithms.

TWEETABLE ABSTRACT

Algorithm development for standardised approaches to managing PPH in low-resource settings.

Predictive performance of Shock Index for postpartum hemorrhage during cesarean delivery

BACKGROUND

The Shock Index (SI), defined as heart rate divided by systolic blood pressure, is reportedly an early surrogate indicator for postpartum hemorrhage (PPH). However, most previous studies have used clinical data of women who delivered vaginally. Therefore, we aimed to evaluate the SI pattern during cesarean delivery and determine its usefulness in detecting PPH.

METHODS

This was a single-center retrospective study using the clinical data of women (n = 331) who underwent cesarean delivery under spinal anesthesia at term between 2018 and 2021. We assessed the SI pattern stratified by total blood loss and evaluated the predictive performance of each vital sign in detecting PPH (total blood loss ≥1000 mL) based on the area under the receiver operating characteristic curve (AUROC).

RESULTS

At 10-15 min after delivery, the mean SI peaked between 0.84 and 0.90 and then decreased to a level between 0.72 and 0.77, which was similar to that upon entering the operating room. Among 331 women, 91 (27.5%) were diagnosed with PPH. There was no correlation between SI and total blood loss (rs = 0.02). The SI had low ability to detect PPH (AUROC 0.54, 95% confidence interval 0.47 to 0.61), which was similar to other vital signs (AUROCs 0.53-0.56).

CONCLUSION

We determined the pattern of SI during cesarean delivery. We found no correlation between SI and total blood loss. Unlike in vaginal delivery, the prognostic accuracy of SI for PPH detection in cesarean delivery was low.

Evaluation of the holding-up uterus technique for placenta accreta spectrum cesarean hysterectomy in shocked patients with a high shock index: a case series study

BACKGROUND

Placenta accreta spectrum (PAS) cesarean hysterectomy is performed under conditions of shock and can result in serious complications. This study aimed to evaluate the usefulness of the "Holding-up uterus" surgical technique with a shock index (S.I.) > 1.5.

METHODS

Twelve patients who underwent PAS cesarean hysterectomy were included in the study.

RESULTS

Group I had S.I. > 1.5, and group II had S.I. ≤ 1.5. Group I had more complications, but none were above Grade 3 or fatal. Preoperative scheduled uterine artery embolization did not result in serious complications, but three patients who had emergency common iliac artery balloon occlusion (CIABO) and a primary total hysterectomy with S.I. > 1.5 had postoperative Grade 2 thrombosis. Two patients underwent manual ablation of the placenta under CIABO to preserve the uterus, both with S.I. > 1.5.

CONCLUSIONS

The study found that the "Holding-up uterus" technique was safe, even in critical situations with S.I. > 1.5. CIABO had no intervention effect. The study also identified assisted reproductive technology pregnancies with a uterine cavity length of less than 5 cm before conception as a critical factor.

Abnormal obstetric shock index and associated factors among immediate postpartum women following vaginal delivery at a tertiary hospital in southwestern Uganda

BACKGROUND

Early recognition of haemodynamic instability after birth and prompt interventions are necessary to reduce adverse maternal outcomes due to postpartum haemorrhage. Obstetric shock Index (OSI) has been recommended as a simple, accurate, reliable, and low-cost early diagnostic measure that identifies hemodynamically unstable women.

OBJECTIVES

We determined the prevalence of abnormal obstetric shock index and associated factors among women in the immediate postpartum period following vaginal delivery at Mbarara Regional Referral Hospital (MRRH) in southwestern Uganda.

METHODS

We conducted a cross-sectional study at the labour suite and postnatal ward of MRRH from January 2022 to April 2022. We systematically sampled women who had delivered vaginally, and measured their blood pressures and pulse rates at 1 h postpartum. We excluded mothers with hypertensive disorders of pregnancy. Sociodemographic, medical and obstetric data were obtained through interviewer-administered questionnaires. The prevalence of abnormal OSI was the proportion of participants with an OSI ≥ 0.9 (calculated as the pulse rate divided by the systolic BP). Logistic regression analysis was used to determine associations between abnormal OSI and independent variables.

RESULTS

We enrolled 427 women with a mean age of 25.66 ± 5.30 years. Of these, 83 (19.44%), 95% CI (15.79-23.52) had an abnormal obstetric shock index. Being referred [aPR 1.94, 95% CI (1.31-2.88), p = 0.001], having had antepartum haemorrhage [aPR 2.63, 95% CI (1.26-5.73), p = 0.010] and having a visually estimated blood loss > 200 mls [aPR 1.59, 95% CI (1.08-2.33), p = 0.018] were significantly associated with abnormal OSI.

CONCLUSION

Approximately one in every five women who delivered vaginally at MRRH during the study period had an abnormal OSI. We recommend that clinicians have a high index of suspicion for haemodynamic instability among women in the immediate postpartum period. Mothers who are referred in from other facilities, those that get antepartum haemorrhage and those with estimated blood loss > 200mls should be prioritized for close monitoring. It should be noted that the study was not powered to study the factors associated with AOSI and therefore the analysis for factors associated should be considered exploratory.

Instructional and didactic support tool for teaching-learning Post-Partum Haemorrhage care in simulated settings: Creation and validation

OBJECTIVE

To describe the creation and validation process of an instructional, didactic and self-applied support tool for teaching-learning Post-Partum Haemorrhage care in simulated settings.

BACKGROUND

Students frequently face difficulties performing the actions in the proper sequence in Post-Partum Haemorrhage simulated cases. Even in a controlled environment, anxiety, nervousness and fear of making mistakes are evident, which render the simulated experience highly stressful. Having a tool with a guideline can help students perform these actions more assertively.

DESIGN

A methodological study to develop a didactic tool.

METHODS

The creation process of the didactic tool, called Instructional Disk for the Management of Post-Partum Haemorrhage, was divided into five phases: Analysis, Design, Development, Implementation and Evaluation. Nine experts specialised in Obstetrics and Midwifery validated the tool by answering a questionnaire with nine items; in turn, 32 undergraduate Midwifery program students carried out the evaluation using a questionnaire on applicability, functionality, clarity, coherence and usability of the tool in Post-Partum Haemorrhage simulated stations. The data were analysed descriptively, considering absolute agreement when the answers to all questions in the five-point Likert scale corresponded to 5 (I totally agree). The Content Validity Index was calculated for the experts' questionnaires.

RESULTS

In the validation stage, the experts agreed or totally agreed with all nine items, reaching a Content Validity Index = 1. In the total scores assigned by the experts, there was a variation between 80.0% and 100% absolute agreement, with a mean of 95.6%. In the students' assessment, the variation was between 87.5% and 100% absolute agreement, with a mean of 97.7%, in the eight items evaluated. The agreement level above 90% among experts and students was considered high.

CONCLUSIONS

The Instructional Disk for the Management of Post-Partum Haemorrhage was validated by experts with extensive experience in Obstetrics and Midwifery care and teaching, ensuring that the content included in the guidelines for the management of Post-Partum Haemorrhage adopted in Brazil is covered. The students positively evaluated this support tool for learning the care to be provided in Post-Partum Haemorrhage cases in the simulated stations.

Quantification of blood loss for the diagnosis of postpartum hemorrhage: a systematic review and meta-analysis

OBJECTIVE

to compare the effectiveness of different diagnostic methods to estimate postpartum blood volume loss.

METHODS

a systematic review of effectiveness according to PRISMA and JBI Protocol. Searches in PubMed/MEDLINE, LILACS, Scopus, Embase, Web of Science and CINAHL, with descriptor "Postpartum Hemorrhage" associated with keyword "Quantification of Blood Loss". Tabulated extracted data, presented in metasynthesis and meta-analysis was applied to quantitative data. To assess risk of bias, JBI Appraisal Tools were applied.

RESULTS

fourteen studies were included, published between 2006 and 2021. Quantification of loss by any method was superior to visual estimation and is highly recommended, however the studies' high heterogeneity did not allow estimating this association.

CONCLUSION

the studies' high heterogeneity, with a probable margin of error given the uncontrolled factors, indicates the need for further studies, however quantification proved to be effective in relation to visual estimate. PROSPERO registration CRD 42021234486.

Prevalence of risk factors for primary postpartum hemorrhage in a university hospital

OBJECTIVES

to identify the risk factors associated with primary postpartum hemorrhage in a university hospital.

METHODS

a cross-sectional study was conducted with 277 postpartum women who received care during childbirth or cesarean section between June and August 2020. Data were collected using a pre-structured questionnaire administered 24 hours after delivery. Poisson Regression was employed to analyze the factors associated with postpartum hemorrhage.

RESULTS

postpartum hemorrhage was observed in 30% of the study sample. Shock Index and uterine distension were found to be statistically associated with postpartum hemorrhage. Postpartum women with a Shock Index ≥ 0.9 had a 61% higher prevalence of postpartum hemorrhage (PR=1.61, 95% CI: 1.07 - 2.43), while those with uterine distension had a 134% higher prevalence (PR=2.34, 95% CI: 1.63 - 3.36).

CONCLUSIONS

recognizing these factors contributes to improvements in clinical practice, as they enable the prediction of their occurrence and call for appropriate management, thereby preventing unfavorable outcomes.

Development and evaluation of a wearable peripheral vascular compensation sensor in a swine model of hemorrhage

Postpartum hemorrhage (PPH) is the leading and most preventable cause of maternal mortality, particularly in low-resource settings. PPH is currently diagnosed through visual estimation of blood loss or monitoring of vital signs. Visual assessment routinely underestimates blood loss beyond the point of pharmaceutical intervention. Quantitative monitoring of hemorrhage-induced compensatory processes, such as the constriction of peripheral vessels, may provide an early alert for PPH. To this end, we developed a low-cost, wearable optical device that continuously monitors peripheral perfusion via laser speckle flow index (LSFI) to detect hemorrhage-induced peripheral vasoconstriction. The measured LSFI signal produced a linear response in phantom models and a strong correlation coefficient with blood loss averaged across subjects (>0.9) in a large animal model, with superior performance to vital sign metrics.

Preoperative shock index in major abdominal emergency surgery

Introduction

Major abdominal emergency surgery (MAES) patients have a high risk of mortality and complications. The time-sensitive nature of MAES necessitates an easily calculable risk-scoring tool. Shock index (SI) is obtained by dividing heart rate (HR) by systolic blood pressure (SBP) and provides insight into a patient's haemodynamic status. We aimed to evaluate SI's usefulness in predicting postoperative mortality, acute kidney injury (AKI), requirements for intensive care unit (ICU) and high-dependency monitoring, and the ICU length of stay (LOS).

Method

We retrospectively reviewed 212,089 MAES patients from January 2013 to December 2020. The cohort was propensity matched, and 3960 patients were included. The first HR and SBP recorded in the anaesthesia chart were used to calculate SI. Regression models were used to investigate the association between SI and outcomes. The relationship between SI and survival was explored with Kaplan-Meier curves.

Results

There were significant associations between SI and mortality at 1 month (odds ratio [OR] 2.40 [1.67-3.39], P<0.001), 3 months (OR 2.13 [1.56-2.88], P<0.001), and at 2 years (OR 1.77 [1.38-2.25], P<0.001). Multivariate analysis revealed significant relationships between SI and mortality at 1 month (OR 3.51 [1.20-10.3], P=0.021) and at 3 months (OR 3.05 [1.07-8.54], P=0.034). Univariate and multivariate analysis also revealed significant relationships between SI and AKI (P<0.001), postoperative ICU admission (P<0.005) and ICU LOS (P<0.001). SI does not significantly affect 2-year mortality.

Conclusion

SI is useful in predicting postopera-tive mortality at 1 month, 3 months, AKI, postoperative ICU admission and ICU LOS.

CRADLE-5: a stepped-wedge type 2 hybrid implementation-effectiveness cluster randomised controlled trial to evaluate the real-world scale-up of the CRADLE Vital Signs Alert intervention into routine maternity care in Sierra Leone-study protocol

BACKGROUND

The CRADLE Vital Signs Alert intervention (an accurate easy-to-use device that measures blood pressure and pulse with inbuilt traffic-light early warning system, and focused training package) was associated with reduced rates of eclampsia and maternal death when trialled in urban areas in Sierra Leone. Subsequently, implementation was successfully piloted as evidenced by measures of fidelity, feasibility and adoption. The CRADLE-5 trial will examine whether national scale-up, including in the most rural areas, will reduce a composite outcome of maternal and fetal mortality and maternal morbidity and will evaluate how the CRADLE package can be embedded sustainably into routine clinical pathways.

METHODS

CRADLE-5 is a stepped-wedge cluster-randomised controlled trial of the CRADLE intervention compared to routine maternity care across eight rural districts in Sierra Leone (Bonthe, Falaba, Karene, Kailahun, Koinadugu, Kono, Moyamba, Tonkolili). Each district will cross from control to intervention at six-weekly intervals over the course of 1 year (May 2022 to June 2023). All women identified as pregnant or within six-weeks postpartum presenting for maternity care in the district are included. Primary outcome data (composite rate of maternal death, stillbirth, eclampsia and emergency hysterectomy) will be collected. A mixed-methods process and scale-up evaluation (informed by Medical Research Council guidance for complex interventions and the World Health Organization ExpandNet tools) will explore implementation outcomes of fidelity, adoption, adaptation and scale-up outcomes of reach, maintenance, sustainability and integration. Mechanisms of change and contextual factors (barriers and facilitators) will be assessed. A concurrent cost-effectiveness analysis will be undertaken.

DISCUSSION

International guidance recommends that all pregnant and postpartum women have regular blood pressure assessment, and healthcare staff are adequately trained to respond to abnormalities. Clinical effectiveness to improve maternal and perinatal health in more rural areas, and ease of integration and sustainability of the CRADLE intervention at scale has yet to be investigated. This trial will explore whether national scale-up of the CRADLE intervention reduces maternal and fetal mortality and severe maternal adverse outcomes and understand the strategies for adoption, integration and sustainability in low-resource settings. If successful, the aim is to develop an adaptable, evidence-based scale-up roadmap to improve maternal and infant outcomes.

TRIAL REGISTRATION

ISRCTN 94429427. Registered on 20 April 2022.

Evaluation During Postpartum Hemorrhage

Postpartum hemorrhage is an obstetric emergency that is the leading and the most preventable cause of maternal death that occurs on the day of birth. The treatment of postpartum hemorrhage in a timely fashion is crucial to prevent morbidity and mortality. The accurate assessment of blood loss during delivery and the postpartum period remains a major challenge. Hence, it is imperative to have a standardized evaluation strategy for accurate assessment of blood loss, adequate classification of hemorrhage, and timely initiated interventions. The multidisciplinary evaluation strategy should be in place regardless of the delivery route.

Interventions of Postpartum Hemorrhage

Postpartum hemorrhage is a common and potentially life-threatening obstetric complication, with successful management relying heavily on early identification of hemorrhage and prompt intervention. This article will review the management of postpartum hemorrhage, including initial steps, exam-specific interventions, medical therapy, minimally invasive, and surgical interventions.

Review of Current Insights and Therapeutic Approaches for the Treatment of Refractory Postpartum Hemorrhage

Refractory postpartum hemorrhage (PPH) affects 10-20% of patients with PPH when they do not respond adequately to first-line treatments. These patients require second-line interventions, including three or more uterotonics, additional medications, transfusions, non-surgical treatments, and/or surgical intervention. Multiple studies have suggested that patients with refractory PPH have different clinical characteristics and causes of PPH when compared to patients who respond to first-line agents. This review highlights current insights into therapeutic approaches for the management of refractory PPH. Early management of refractory PPH relies on both hypovolemic resuscitation and achievement of hemostasis, with an emphasis on early blood product replacement and massive transfusion protocols. Transfusion needs can be more rapidly and accurately identified through point-of-care tests such as thromboelastography. Medical therapies for the treatment of refractory PPH involve treatment of both uterine atony as well as the underlying coagulopathy, with the use of tranexamic acid and adjunct therapies such as factor replacement. The principles guiding the management of refractory PPH include restoring normal uterine and pelvic anatomy, through the evaluation and management of retained products of conception, uterine inversion, and obstetric lacerations. Intrauterine vacuum-induced hemorrhage control devices are novel methods for the treatment of refractory PPH secondary to uterine atony, in addition to other uterine-sparing surgical procedures that are under investigation. Resuscitative endovascular balloon occlusion of the aorta can be considered for cases of critical refractory PPH, to prevent or decrease ongoing blood loss while definitive surgical interventions are performed. Finally, for patients with critical hemorrhage resulting in hemorrhagic shock, damage control resuscitation (a staged surgical approach focused on restoring normal physiologic recovery and maximizing tissue oxygenation prior to proceeding with definitive surgical management) has been shown to successfully control refractory PPH, with an overall mortality decrease for obstetric patients.

Management of severe peri-operative bleeding: Guidelines from the European Society of Anaesthesiology and Intensive Care: Second update 2022

BACKGROUND

Management of peri-operative bleeding is complex and involves multiple assessment tools and strategies to ensure optimal patient care with the goal of reducing morbidity and mortality. These updated guidelines from the European Society of Anaesthesiology and Intensive Care (ESAIC) aim to provide an evidence-based set of recommendations for healthcare professionals to help ensure improved clinical management.

DESIGN

A systematic literature search from 2015 to 2021 of several electronic databases was performed without language restrictions. Grading of Recommendations, Assessment, Development and Evaluation (GRADE) was used to assess the methodological quality of the included studies and to formulate recommendations. A Delphi methodology was used to prepare a clinical practice guideline.

RESULTS

These searches identified 137 999 articles. All articles were assessed, and the existing 2017 guidelines were revised to incorporate new evidence. Sixteen recommendations derived from the systematic literature search, and four clinical guidances retained from previous ESAIC guidelines were formulated. Using the Delphi process on 253 sentences of guidance, strong consensus (>90% agreement) was achieved in 97% and consensus (75 to 90% agreement) in 3%.

DISCUSSION

Peri-operative bleeding management encompasses the patient's journey from the pre-operative state through the postoperative period. Along this journey, many features of the patient's pre-operative coagulation status, underlying comorbidities, general health and the procedures that they are undergoing need to be taken into account. Due to the many important aspects in peri-operative nontrauma bleeding management, guidance as to how best approach and treat each individual patient are key. Understanding which therapeutic approaches are most valuable at each timepoint can only enhance patient care, ensuring the best outcomes by reducing blood loss and, therefore, overall morbidity and mortality.

CONCLUSION

All healthcare professionals involved in the management of patients at risk for surgical bleeding should be aware of the current therapeutic options and approaches that are available to them. These guidelines aim to provide specific guidance for bleeding management in a variety of clinical situations.

Development and evaluation of a wearable peripheral vascular compensation sensor in a swine model of hemorrhage

Postpartum hemorrhage (PPH) is both the leading and most preventable cause of maternal mortality. PPH is currently diagnosed through visual estimation of blood loss or vital sign analysis of shock index (ratio of heart rate to systolic blood pressure). Visual assessment underestimates blood loss, particularly in the setting of internal bleeding, and compensatory mechanisms stabilize hemodynamics until hemorrhage is massive, beyond the point of pharmaceutical intervention. Quantitative monitoring of hemorrhage-induced compensatory processes, such as the constriction of peripheral vessels to shunt blood to the central organs, may provide an early alert for PPH. To this end, we developed a low-cost, wearable optical device that continuously monitors peripheral perfusion via laser speckle flow index (LSFI) to detect hemorrhage-induced peripheral vasoconstriction. The device was first tested using flow phantoms across a range of physiologically relevant flow rates and demonstrated a linear response. Subsequent testing occurred in swine hemorrhage studies (n=6) by placing the device on the posterior side of the swine's front hock and withdrawing blood from the femoral vein at a constant rate. Resuscitation with intravenous crystalloids followed the induced hemorrhage. The mean LSFI vs. percent estimated blood volume loss had an average correlation coefficient of -0.95 during the hemorrhage phase and 0.79 during resuscitation, both of which were superior to the performance of the shock index. With continued development, this noninvasive, low-cost, and reusable device has global potential to provide an early alert of PPH when low-cost and accessible management strategies are most effective, helping to reduce maternal morbidity and mortality from this largely preventable problem.

'A prospective case control study to evaluate shock index for identifying patients at risk of clinically important malaria in refugee settings'

Bidibidi Refugee Settlement's 223,000 refugees are vulnerable to malaria due to crowded conditions and limited healthcare access. Early identification and referral of suspected cases is key to reduce morbidity and mortality. We evaluated the shock index (heart rate/ systolic blood pressure) for detection of abnormal vital signs, calculated by the CRADLE Vital Signs Alert device, which can be used in routine patient blood pressure and heart rate assessment by non-medically trained Voluntary Health Team workers. The single most frequent diagnosis causing shock was malaria, and thus the device was useful to detect severe cases (as well as discovering other cases), after calculating appropriate shock indices.

Scale-up of a novel vital signs alert device to improve maternity care in Sierra Leone: a mixed methods evaluation of adoption

BACKGROUND

The CRADLE (Community blood pressure monitoring in Rural Africa: Detection of underLying pre-Eclampsia) Vital Signs Alert device-designed specifically to improve maternity care in low resource settings-had varying impact when trialled in different countries. To better understand the contextual factors that may contribute to this variation, this study retrospectively evaluated the adoption of CRADLE, during scale-up in Sierra Leone.

METHODS

This was a mixed methods study. A quantitative indicator of adoption (the proportion of facilities trained per district) was calculated from existing training records, then focus groups were held with 'CRADLE Champions' in each district (n = 32), to explore adoption qualitatively. Template Analysis was used to deductively interpret qualitative data, guided by the NASSS (non-adoption, abandonment, scale-up, spread, sustainability) Framework.

FINDINGS

Substantial but non-significant variation was found in the proportion of facilities trained in each district (range 59-90%) [X² (7, N = 8) = 10.419, p = 0.166]. Qualitative data identified complexity in two NASSS domains that may have contributed to this variation: 'the technology' (for example, charging issues, difficulty interpreting device output and concerns about ongoing procurement) and 'the organisation' (for example, logistical barriers to implementing training, infighting and high staff turnover). Key strategies mentioned to mitigate against these issues included: transparent communication at all levels; encouraging localised adaptations during implementation (including the involvement of community leaders); and selecting Champions with strong soft skills (particularly conflict resolution and problem solving).

CONCLUSIONS

Complexity related to the technology and the organisational context were found to influence the adoption of CRADLE in Sierra Leone, with substantial inter-district variation. These findings emphasise the importance of gaining an in-depth understanding of the specific system and context in which a new healthcare technology is being implemented. This study has implications for the ongoing scale-up of CRADLE, and for those implementing or evaluating other health technologies in similar contexts.

The role of fibrinogen in postpartum hemorrhage

Postpartum hemorrhage (PPH) is the leading cause of maternal death worldwide (WHO), with almost 60000 deaths annually. Pregnancy is a prothrombotic state with increased levels of several coagulation factors to protect the parturient from bleeding problems during delivery. Fibrinogen has a significant role in coagulation and bleeding. Studies have pointed out that lower fibrinogen levels before delivery, but also at the initiation of PPH, are predictive of major hemorrhage. Early, the goal-directed fibrinogen concentrate therapy might be very useful in a subgroup of patients with serious PPH. This review aims to summarize the current literature on fibrinogen during PPH.

Identifying interventions to reduce peripartum haemorrhage associated with caesarean delivery in Africa: A Delphi consensus study

Women in Africa are fifty times more likely than in high-income settings to die following caesarean delivery, and peripartum haemorrhage is most strongly associated with mortality. We aimed to establish consensus on which interventions are considered most feasible to implement and most effective at reducing haemorrhage associated with caesarean delivery across Africa. We conducted a Delphi consensus study, including obstetric and anaesthesia providers from across Africa. In round one the expert group proposed key interventions for consideration. In rounds two and three the interventions were ranked on a 9-point Likert scale for effectiveness and feasibility. Round four was an online discussion to establish consensus on effectiveness and feasibility of interventions for which this had not been reached in round three. Twenty-eight interventions were considered both highly effective and feasible in Africa. Interventions covered a range of fields, categorised into direct- or indirect interventions. Direct interventions included: risk assessment and screening; checklists and protocols; monitoring and surveillance; availability of resources; ability to perform technical skills. Indirect interventions included: community and maternal education; contraception and family planning; minimum training standards; referral patterns and delays; advocacy to key stakeholders; simulation and team training; and 24-hour access to safe emergency caesarean delivery. Interventions considered both effective and feasible in reducing peripartum haemorrhage associated with caesarean delivery in Africa were identified. A multi-layered implementation strategy, including immediately developing a perioperative caesarean delivery bundle of care, in addition to longer-term public health measures may have a profound impact on maternal mortality in Africa.

Plasental invazyon anomalisi olan hastalarda anestezi yönetimi: Tek merkez deneyimi

Aim: Postpartum hemorrhage is a life-threatening obstetric emergent clinical situation accompanied by blood loss of more than 500 ml after vaginal delivery and more than 1000 ml after cesarean section. This situation, frequently encountered in placental adhesion anomalies, is essential in terms of follow-up, treatment, and multidisciplinary management. We aimed to retrospectively evaluate the perioperative anesthesia management, transfusion requirement, and postoperative intensive care unit requirement of patients diagnosed with placental invasion anomaly who had an intraoperative hemorrhage Methods: In our single-center study, a total of 58 female patients diagnosed with of placental invasion anomaly with a cesarean section between 2017-2020 were examined. Patients under 18 years of age and missing data were excluded from the study. Demographic data of patients (age, American Society of Anesthesiologists score (ASA)), diagnosis, duration of operation, perioperative laboratory findings, anesthesia type, perioperative hemodynamics (highest heart rate, lowest mean arterial pressure, shock index), amount of bleeding, blood products, and fluids used, surgical interventions (B-Lynch, Bacri balloon application, uterine artery ligation, hysterectomy), intraoperative vasopressor/inotrope use, ICU stay, laboratory results in the first 24 hours postoperatively, and total hospital stay were recorded. Results: In the preoperative evaluation, 27 (46.5%) patients were diagnosed with placenta accreta, and placenta previa was diagnosed in 19 (32.7%) patients. Perioperatively mean of 3.08 ± 1.7 units of Red blood cell was used. In patients with postoperative intensive care unit hospitalization, the highest intraoperative lactate value was 3.5±1.8 mmol/L, shock index was 1.3±0.3 (0.6-1.8). In patients given intraoperative fibrinogen concentrate, the intraoperative shock index was 1.5±0.2 (0.9-1.8), the amount of intraoperative bleeding was 2575±302.2 ml, and the fibrinogen levels measured in the first 24 hours after surgery were 294.7±79.7 mg/dl. Conclusions: Anesthesia management of patients diagnosed with abnormal placental invasion is important because of significant hemorrhage. Due to unstable hemodynamics, preoperative blood product preparation with a multidisciplinary approach and a postoperative intensive care unit plan should be made for these patients.

Predictive accuracy of the shock index for severe postpartum hemorrhage in high-income countries: A systematic review and meta-analysis

AIM

The shock index has been suggested as a screening tool for predicting postpartum hemorrhage (PPH); however, there is little comprehensive evidence regarding its predictive accuracy. This systematic review and meta-analysis aim to investigate the predictive accuracy of the shock index for severe PPH in high-income countries.

METHODS

A comprehensive search was conducted on MEDLINE, Cochrane Central Register of Controlled Trials, and Web of Science (from inception to June 2021). Studies assessing the predictive performance of the shock index for PPH in high-income countries were included. Two or more reviewers independently extracted the data and assessed the risk of bias and applicability concerns using the modified Quality Assessment of Diagnostic Accuracy Studies 2 tool. PPH requiring higher-level care, such as blood transfusions, were considered as primary analyses. We described the hierarchical summary receiver-operating characteristic curve for data synthesis.

RESULTS

Nine studies were included after the eligibility assessment. All studies were considered to either have a high risk of bias or high applicability concerns. The sensitivity of the four studies that defined severe PPH as PPH requiring blood transfusion ranged from 0.51 to 0.80, whereas their specificity ranged from 0.33 to 0.92.

CONCLUSIONS

This review shows that the predictive performance of the shock index for severe PPH is inconsistent. Therefore, the evidence for using the shock index alone as a screening tool for PPH in high-income countries is insufficient.

STUDY REGISTRATION

This review was prospectively registered with the University Hospital Medical Information Network Clinical Trials Registry (UMIN000044230).

Postpartum haemorrhage in anaemic women: assessing outcome measures for clinical trials

Background

Postpartum haemorrhage (PPH) is a leading cause of maternal mortality worldwide. Maternal anaemia greatly increases the risk of PPH, and over a third of all pregnant women are anaemic. Because anaemia reduces the oxygen-carrying capacity of the blood, anaemic women cannot tolerate the same volume of blood loss as healthy women. Yet the same blood loss threshold is used to define PPH in all women. The lack of an established PPH definition in anaemic women means the most appropriate outcome measures for use in clinical trials are open to question. We used data from the WOMAN-2 trial to examine different definitions of PPH in anaemic women and consider their appropriateness as clinical trial outcome measures.

Main body

The WOMAN-2 trial is assessing tranexamic acid (TXA) for PPH prevention in women with moderate or severe anaemia at baseline. To obtain an accurate, precise estimate of the treatment effect, outcome measures should be highly specific and reasonably sensitive. Some outcome misclassification is inevitable. Low sensitivity reduces precision, but low specificity biases the effect estimate towards the null. Outcomes should also be related to how patients feel, function, or survive. The primary outcome in the WOMAN-2 trial, a ‘clinical diagnosis of PPH’, is defined as estimated blood loss > 500 ml or any blood loss within 24 h sufficient to compromise haemodynamic stability. To explore the utility of several PPH outcome measures, we analysed blinded data from 4521 participants. For each outcome, we assessed its: (1) frequency, (2) specificity for significant bleeding defined as shock index ≥1.0 and (3) association with fatigue (modified fatigue symptom inventory [MFSI]), physical endurance (six-minute walk test) and breathlessness. A clinical diagnosis of PPH was sufficiently frequent (7%), highly specific for clinical signs of early shock (95% specificity for shock index ≥1) and associated with worse maternal functioning after childbirth.

Conclusion

Outcome measures in clinical trials of interventions for PPH prevention should facilitate valid and precise estimation of the treatment effect and be important to women. A clinical diagnosis of PPH appears to meet these criteria, making it an appropriate primary outcome for the WOMAN-2 trial.

Trial registration

ClinicalTrials.gov NCT03475342, registered on 23 March 2018; ISRCTN62396133, registered on 7 December 2017; Pan African Clinical Trial Registry PACTR201909735842379, registered on 18 September 2019.

The assessment of blood pressure in pregnant women: pitfalls and novel approaches

Accurate assessment of blood pressure is fundamental to the provision of safe obstetrical care. It is simple, cost effective, and life-saving. Treatments for preeclampsia, including antihypertensive drugs, magnesium sulfate, and delivery, are available in many settings. However, the instigation of appropriate treatment relies on prompt and accurate recognition of hypertension. There are a number of different techniques for blood pressure assessment, including the auscultatory method, automated oscillometric devices, home blood pressure monitoring, ambulatory monitoring, and invasive monitoring. The auscultatory method with a mercury sphygmomanometer and the use of Korotkoff sounds was previously recommended as the gold standard technique. Mercury sphygmomanometers have been withdrawn owing to safety concerns and replaced with aneroid devices, but these are particularly prone to calibration errors and regular calibration is imperative to ensure accuracy. Automated oscillometric devices are straightforward to use, but the physiological changes in healthy pregnancy and pathologic changes in preeclampsia may affect the accuracy of a device and monitors must be validated. Validation protocols classify pregnant women as a "special population," and protocols must include 15 women in each category of normotensive pregnancy, hypertensive pregnancy, and preeclampsia. In addition to a scarcity of devices validated for pregnancy and preeclampsia, other pitfalls that cause inaccuracy include the lack of training and poor technique. Blood pressure assessment can be affected by maternal position, inappropriate cuff size, conversation, caffeine, smoking, and irregular heart rate. For home blood pressure monitoring, appropriate instruction should be given on how to use the device. The classification of hypertension and hypertensive disorders of pregnancy has recently been revised. These are classified as preeclampsia, transient gestational hypertension, gestational hypertension, white-coat hypertension, masked hypertension, chronic hypertension, and chronic hypertension with superimposed preeclampsia. Blood pressure varies across gestation and by ethnicity, but gestation-specific thresholds have not been adopted. Hypertension is defined as a sustained systolic blood pressure of ≥140 mm Hg or a sustained diastolic blood pressure of ≥90 mm Hg. In some guidelines, the threshold of diagnosis depends on the setting in which blood pressure measurement is taken, with a threshold of 140/90 mm Hg in a healthcare setting, 135/85 mm Hg at home, or a 24-hour average blood pressure on ambulatory monitoring of >126/76 mm Hg. Some differences exist among organizations with respect to the criteria for the diagnosis of preeclampsia and the correct threshold for intervention and target blood pressure once treatment has been instigated. Home blood pressure monitoring is currently a focus for research. Novel technologies, including early warning devices (such as the CRADLE Vital Signs Alert device) and telemedicine, may provide strategies that prompt earlier recognition of abnormal blood pressure and therefore improve management. The purpose of this review is to provide an update on methods to assess blood pressure in pregnancy and appropriate technique to optimize accuracy. The importance of accurate blood pressure assessment is emphasized with a discussion of preeclampsia prediction and treatment of severe hypertension. Classification of hypertensive disorders and thresholds for treatment will be discussed, including novel developments in the field.

Prognosticating Fetomaternal ICU Outcomes

Although no scoring system is as yet fully validated for predicting maternal outcomes in critically ill obstetric patients, prognostication may be done objectively using severity predicting models. General critical care scoring systems which have been studied in obstetric patients are outcome prediction models (Acute Physiology and Chronic Health Evaluation [APACHE] I-IV, Simplified Acute Physiology Score [SAPS] I-III, Mortality Probability Model [MPM] I-IV) and organ dysfunction scores (Multiple Organ Dysfunction Score [MODS], Logistic Organ Dysfunction Score [LODS], Sequential Organ Failure Assessment [SOFA]). General critical care scoring systems may overpredict mortality rates in obstetric patients secondary to an altered physiology of organ systems during pregnancy. Obstetric prediction models were developed keeping in mind the physiological characteristics of obstetric population. They are Modified Early Obstetric Warning System (MEOWS), Obstetric Early Warning Score (OEWS), Maternal Early Warning Trigger (MEWT), and disease-specific obstetric scoring systems. The APACHE II model and MPM II are most often used scoring systems for predicting maternal mortality. The SOFA model is the best predictive model for sepsis in obstetrics. APACHE II and SAPS are more useful for nonobstetric population. Recent studies have also underscored the applicability of the OEWS in intensive care unit (ICU) settings with results comparable to the more elaborate APACHE II and SOFA scores. The Early Warning System helps in identifying acutely deteriorating pregnant and postpartum women in non-ICU settings who may require critical care. Fetal outcomes are largely dependent upon maternal outcomes. Prognostic systems applied to mothers may help in estimation of perinatal mortality and morbidity.

Shock index predicts up to 90-day mortality risk after intracerebral haemorrhage

BACKGROUND

Shock index (SI - heart rate/systolic blood pressure) has been studied as a measure of haemodynamic status. We aimed to determine whether SI measures within 72 h of admission were associated with adverse outcomes in intracerebral haemorrhage (ICH).

METHODS

Patients were drawn from the Virtual International Stroke Trials Archive-Intracerebral Haemorrhage (VISTA-ICH). Multivariable Cox regressions modelled the relationship between SI (on admission, 24, 48, 72 h) and mortality (at 3-, 7-, and 90-days), 90-day incident pneumonia and cardiovascular events (MACE). Ordinal logistic regressions modelled the relationship between SI and 90-day modified Rankin Scale (mRS).

RESULTS

979 patients were included. Baseline SI was not associated with mortality. 24 h SI > 0.7 was associated with 7-day mortality (hazard ratio (95% confidence interval) = 3.14 (1.37-7.19)). 48 h and 72 h SI > 0.7 were associated with 7-day (4.23 (2.07-8.66) and 3.24 (1.41-7.42) respectively) and 90-day mortality (2.97 (1.82-4.85) and 2.05 (1.26-3.61) respectively). SI < 0.5 at baseline, 48 h and 72 h was associated with decreased pneumonia risk. 24 h and 48 h SI > 0.7was associated with increased MACE risk. 48 h and 72 h SI > 0.7 was associated with increased odds of higher 90-day mRS.

CONCLUSION

Higher-than-normal SI subsequent to initial encounter was associated with higher post-ICH mortality at 3, 7, and 90 days. Lower-than-normal SI was associated with a decreased risk of incident pneumonia.

The golden hour for postpartum hemorrhage: Results from a prospective cohort study

OBJECTIVE

To evaluate the predictive capacity of vital signs for the diagnosis of postpartum hemorrhage (PPH).

METHODS

A prospective cohort study performed at the University of Campinas, Brazil, between February 2015 and March 2016 with women who delivered vaginally. Vital signs and postpartum bleeding were collected over 24 h. Exploratory data analysis was performed plus receiver operating characteristic curve analysis where the areas under the curve was used to determine the best cutoff points for sensitivity, specificity, likelihood ratio, and diagnostic odds ratio.

RESULTS

For the 270 women recruited, mean blood loss after 120 min was 427.49 ± 335.57 ml, while 84 (31.1%) and 22 (8.1%) women had blood loss ≥500 and ≥1000 ml, respectively. Heart rate cutoff point of 105 bpm measured between 21-40 min after birth identified blood loss ≥1000 ml with 90% specificity. A shock index (SI) of 0.965 at 41-60 min after birth identified blood loss ≥500 and ≥1000 ml within 2 h with approximately 95% specificity.

CONCLUSION

Shock index and heart rate measured after birth showed high specificity with low sensitivity to identify PPH. In clinical practice, "The rule of 1s" should receive special attention: SI ≥1, or heart rate >100 bpm, or estimated blood loss ≥1 L.

The utility of shock index and heart rate in the management of postpartum blood loss in pregnant women complicated with hypertensive disorders in pregnancy

BACKGROUND

Although the shock index (SI) (heart rate/systolic blood pressure) and heart rate (HR) are a helpful indicator in the management of postpartum blood loss, there are few reports of SI in pregnant women complicated with hypertensive disorders in pregnancy (HDP). The purpose of this study was to examine whether SI and HR would be a clinically helpful indicator, and to detect the cutoff value for judging abnormal obstetric bleeding.

METHODS

This was a retrospective case-control study in 107 patients with HDP in a singleton tertiary perinatal medical facility. The values of postpartum highest SI (peak SI) and highest HR (peak HR), and the amount of bleeding until peak SI and peak HR were retrospectively examined and analyzed. We used the receiver operating characteristic analysis to assess the diagnostic value of peak SI and peak HR for judging abnormal obstetric bleeding.

RESULTS

Peak SI and peak HR were significantly related to the amount of bleeding up to peak SI and up to peak HR. The cutoff values of peak SI with blood loss volumes above 500 ml, 1000 ml, and 1500 ml were 0.77, 0.76, and 0.99, respectively. The cutoff values of peak HR with blood loss volumes above 500 ml, 1000 ml, and 1500 ml were 97, 98, and 103, respectively.

CONCLUSION

In cases of pregnant women complicated with HDP, both SI and HR were probably useful indicators in the management of postpartum blood loss. Further prospective trials are warranted to confirm these results.

Early Maladaptive Cardiovascular Responses are Associated with Mortality in a Porcine Model of Hemorrhagic Shock

BACKGROUND

Hemorrhage is a leading cause of death on the battlefield. Current methods for predicting hemodynamic deterioration during hemorrhage are of limited accuracy and practicality. During a study of the effects of remote ischemic preconditioning in pigs that underwent hemorrhage, we noticed arrhythmias among all pigs that died before the end of the experiment but not among surviving pigs. The present study was designed to identify and characterize the early maladaptive hemodynamic responses (tachycardia in the presence of hypotension without a corresponding increase in cardiac index or mean arterial blood pressure) and their predictive power for early mortality in this experimental model.

METHODS

Controlled hemorrhagic shock was induced in 16 pigs. Hemodynamic parameters were monitored continuously for 7 h following bleeding. Changes in cardiovascular and laboratory parameters were analyzed and compared between those that had arrhythmia and those that did not.

RESULTS

All animals had similar changes in parameters until the end of the bleeding phase. Six animals developed arrhythmias and died early, while 10 had no arrhythmias and survived longer than 6 h or until euthanasia. Unlike survivors, those that died did not compensate for cardiac output (CO), diastolic blood pressure (DBP), and stroke volume (SV). Oxygen delivery (DO2) and mixed venous saturation (SvO2) remained low in animals that had arrhythmia, while achieving certain measures of recuperation in animals that did not. Serum lactate increased earlier and continued to rise in all animals that developed arrhythmias. No significant differences in hemoglobin concentrations were observed between groups.

CONCLUSIONS

Despite similar initial changes in variables, we found that low CO, DBP, SV, DO2, SvO2, and high lactate are predictive of death in this animal model. The results of this experimental study suggest that maladaptive responses across a range of cardiovascular parameters that begin early after hemorrhage may be predictive of impending death, particularly in situations where early resuscitative treatment may be delayed.

Effect of the CRADLE vital signs alert device intervention on referrals for obstetric haemorrhage in low-middle income countries: a secondary analysis of a stepped- wedge cluster-randomised control trial

BACKGROUND

Obstetric haemorrhage is the leading cause of maternal death worldwide, 99% of which occur in low and middle income countries. The majority of deaths and adverse events are associated with delays in identifying compromise and escalating care. Management of severely compromised pregnant women may require transfer to tertiary centres for specialised treatment, therefore early recognition is vital for efficient management. The CRADLE vital signs alert device accurately measures blood pressure and heart rate, calculates the shock index (heart rate divided by systolic blood pressure) and alerts the user to compromise through a traffic light system reflecting previously validated shock index thresholds.

METHODS

This is a planned secondary analysis of data from the CRADLE-3 trial from ten clusters across Africa, India and Haiti where the device and training package were randomly introduced. Referral data were prospectively collected for a 4-week period before, and a 4-week period 3 months after implementation. Referrals from primary or secondary care facilities to higher level care for any cause were recorded. The denominator was the number of women seen for maternity care in these facilities.

RESULTS

Between April 1 2016 and Nov 30th, 2017 536,223 women attended maternity care facilities. Overall, 3.7% (n = 2784/74,828) of women seen in peripheral maternity facilities were referred to higher level care in the control period compared to 4.4% (n = 3212/73,371) in the intervention period (OR 0.89; 0.39-2.05) (data for nine sites that were able to collect denominator). Of these 0.29% (n = 212) pre-intervention and 0.16% (n = 120) post-intervention were referred to higher-level facilities for maternal haemorrhage. Although overall referrals did not significantly reduce there was a significant reduction in referrals for obstetric haemorrhage (OR 0.56 (0.39-0.65) following introduction of the device with homogeneity (i-squared 26.1) between sites. There was no increase in any bleeding-related morbidity (maternal death or emergency hysterectomy).

CONCLUSIONS

Referrals for obstetric haemorrhage reduced following implementation of the CRADLE Vital Signs Alert Device, occurring without an increase in maternal death or emergency hysterectomy. This demonstrates the potential benefit of shock index in management pathways for obstetric haemorrhage and targeting limited resources in low- middle- income settings.

TRIAL REGISTRATION

This study is registered with the ISRCTN registry, number ISRCTN41244132 (02/02/2016).

A prospective cohort study of shock index as a reliable marker to predict the patient's need for blood transfusion due to postpartum hemorrhage

Objective:

This study was aimed to compare the shock index (SI) values between patients who required blood transfusion due to postpartum hemorrhage (PPH) and patients who received no blood transfusion.

Methods:

We conducted this cross-sectional study at a tertiary center between January 2019 and June 2019. A total of 2534 patients who underwent vaginal delivery were included in this study. We measured SI values upon admission, 30 minutes, 1-hour, and 2-hours after delivery. We identified women who required blood transfusion as the study group. Control patients who delivered in the same period and received no blood transfusion were identified in the medical record system and randomly selected. Age, parity, BMI, and SI values at each one prepartum and three postpartum periods of the groups were analyzed.

Results:

A total of 2534 patients were included in the study. A varying amount of blood transfusion was performed in 54 patients (2.13%). When we compared with patients who did not receive blood transfusion after delivery, patients who received any amount of blood transfusion after vaginal delivery had significantly higher SI values 30 minutes after delivery (0.99±0.20, and 085±0.11, p=0.0001), at 1-hour (1.00±0.18, and 0.85±0.11, p=0.0001), and 2-hours (1.09±0.16, and 0.87±0.11, p=0.0001).

Conclusion:

SI value could be a reliable and consistent marker to predict the requirement for any amount of blood transfusion due to PPH.

A review of postpartum hemorrhage in low-income countries and implications for strengthening health systems

Postpartum hemorrhage (PPH) is the leading cause of maternal morbidity and mortality worldwide. Disparities in PPH-associated survival between high and low-/middle-income countries reflect an imperative for low-resource countries to improve strategies for rapid diagnosis and treatment. A review of current PPH diagnosis, prevention, treatment, and access to care in low-income countries has been used to understand, extract, and report the challenges that public health systems face in trying to solve the marked global disparity in PPH outcomes. Improvement in PPH survival begins with holistic strengthening of each step along the continuum of care in health systems and should include performance feedback measures and quality-of-care research.

Hospital transfer for patients with postpartum hemorrhage in Yokohama, Japan: a single‐center descriptive study

Aim

To describe the transport time and timing of transfer of patients with postpartum hemorrhage to a tertiary care institution in an urban area.

Methods

We included patients with postpartum hemorrhage transferred to our hospital from a perinatal care facility. We defined transfer time as the time between the referring physician's request for transfer and the patient's arrival at our hospital. We examined transfer time and its breakdown, the shock index before and after transfer, and the prognosis.

Results

Overall, 79 patients with postpartum hemorrhage were transported to our hospital within a median (interquartile range) of 53 min (47–63 min). In 70 cases (89%), the request for transport was made before the shock index reached 1.5, and two cases had cardiac arrest during transport.

Conclusions

Most patients who were transferred to our hospital were transferred according to the criteria recommended by the guideline. However, the occurrence of cardiac arrest during transport indicates the need to shorten the time from transfer requests to emergency calls by strengthening cooperation with regional perinatal care facilities.

Delta Shock Index Predicts Outcomes in Pediatric Trauma Patients Regardless of Age

INTRODUCTION

Changes in the shock index (ΔSI) can be a predictive tool but is not established among pediatric trauma patients. The aim of our study was to assess the impact of ΔSI on mortality in pediatric trauma patients.

METHODS

We performed a 2017 analysis of all pediatric trauma patients (age 0-16 y) from the ACS-TQIP. SI was defined as heart rate(HR)/systolic blood pressure(SBP). We abstracted the SI in the field (EMS), SI in the emergency department (ED) and calculated the change in SI (ΔSI = ED SI-EMS SI). Patients were divided into four age groups: 0-3 y, 4-6 y, 7-12 y, and 13-16 y and substratified into two groups based on the value of the age-group-specific ΔSI cutoff obtained with receiver operating characteristic ROC analysis; +ΔSI and -ΔSI. Our outcome measure was mortality. Multivariable logistic and Cox regression analyses were performed.

RESULTS

We included 31,490 patients. Mean age was 10.6 ± 4.6 y, and 65.8% were male. The overall mortality rate was 1.4%. In the age group 0-3 y the cutoff point for ΔSI was 0.29 with an area under the curve (AUC) 0.70 [0.62-0.79], ΔSI cutoff 4-6 y was 0.41 AUC 0.81 [0.70-0.92], ΔSI cutoff 7-12 y was 0.05 AUC 0.83 [0.76-0.90], and ΔSI cutoff 13-16 y was 0.13 AUC 0.75 [0.69-0.81]. On the Cox regression analysis, +ΔSI was independently associated with increased in-hospital mortality and 24-h mortality (P ≤ 0.01).

CONCLUSIONS

Vital signs vary by age group in children, but ΔSI inherently accounts for this variation. ΔSI predicts mortality and may be utilized as a predictor to help guide triage of pediatric trauma patients.

LEVEL OF EVIDENCE

Level III Prognostic.

Postpartum hemorrhage

Postpartum hemorrhage is the leading cause of maternal morbidity and mortality worldwide, and incidence in the United States, although lower than in some resource-limited countries, remains high. Women of color are at a disproportionate risk of developing a life-threatening postpartum hemorrhage. Risk assessment tools are available but because they lack specificity and sensitivity, all pregnant women are considered at risk. Early identification of and intervention in a hemorrhage requires an interdisciplinary team approach to care and can save the lives of thousands of women each year.

The association of shock index and haemoglobin variation with postpartum haemorrhage after vaginal delivery: a prospective cohort pilot study

INTRODUCTION

Shock index and continuous non-invasive haemoglobin monitoring (SpHb) have both been proposed for the timely recognition of postpartum haemorrhage (PPH). We sought to determine, in parallel, the association of each of shock index and SpHb with blood loss after vaginal delivery.

METHODS

Sixty-six women were recruited to this prospective observational study. Shock index and SpHb were recorded postpartum for 120 min. The association between each of shock index and SpHb with quantitative blood loss (QBL) at 30, 60 and 120 min postpartum was determined using linear mixed models. Area-under-the-receiver-operator-characteristic (AUROC) curves were constructed to evaluate the diagnostic ability of shock index and SpHb to detect PPH (defined as QBL ≥1000 mL).

RESULTS

Shock index trend was associated with QBL over the first 30 min (r=0.37, P=0.002), but not over 60 or 120 min. There was an association of SpHb trend with QBL over the first 30 min (P=0.06), but not over 60 min (r=-0.32, P=0.009) or 120 min (r=-0.26, P=0.03). Maximum shock index within 60 min correlated with QBL (r=0.54, P <0.001) and was a predictor of PPH (P=0.0012, AUROC 0.796). Maximum change in SpHb within 60 min negatively correlated with QBL (r=-0.4, P <0.001) and was a predictor of PPH (P=0.048, AUROC 0.761).

CONCLUSIONS

The trend of shock index and its peak values are associated with blood loss after vaginal delivery and are early indicators of PPH. Negative trend of SpHb is a late sign of PPH and has a weaker association with blood loss than shock index.

Equivalency between the shock index and subtracting the systolic blood pressure from the heart rate: an observational cohort study

Background

Although the shock index is known to predict mortality and other severe outcomes, deriving it requires complex calculations. Subtracting the systolic blood pressure from the heart rate may produce a simple shock index that would be a clinically useful substitute for the shock index. In this study, we investigated whether the simple shock index was equivalent to the shock index.

Methods

This observational cohort study was conducted at 2 tertiary care hospitals. Patients who were transported by ambulance were recruited for this study and were excluded if they were aged < 15 years, had experienced prehospital cardiopulmonary arrest, or had undergone inter-hospital transfer. Pearson’s product-moment correlation coefficient and regression equation were calculated, and two one-sided tests were performed to examine their equivalency.

Results

Among 5429 eligible patients, the correlation coefficient between the shock index and simple shock index was extremely high (0.917, 95% confidence interval 0.912 to 0.921, P < .001). The regression equation was estimated as sSI = 258.55 log SI. The two one-sided tests revealed a very strong equivalency between the shock index and the index estimated by the above equation using the simple shock index (mean difference was 0.004, 90% confidence interval 0.003 to 0.005).

Conclusion

The simple shock index strongly correlated with the shock index.

Shock Index in the Prediction of Adverse Maternal Outcome

Introduction

WHO states that obstetric hemorrhage, hypertensive disorders of pregnancy and sepsis account for approximately 50% of maternal deaths worldwide. All these conditions are associated with changes in vital signs including blood pressure (BP) and heart rate (HR). Shock index (SI) is the ratio of HR to systolic BP.

Aims and Objectives

To evaluate role of shock index as an early indicator of adverse maternal outcomes and to determine the threshold points of SI for five adverse maternal outcomes.

Methodology

This was a prospective observational study on 1004 consecutively enrolled subjects presenting in labor. Vital signs and Shock Index were recorded. SI thresholds were analyzed with respect to obstetric complications and adverse outcomes. Parametric tests such as Chi-square, comparison of proportions, comparison of mean and ROC curve analysis were applied on the data.

Results

The mean SI value in the vaginal delivery group was 1.02 ± 0.26 and it was 0.95 ± 0.033 in the caesarean delivery group. The values of SI ((Mean and SD) for ICU admission were (1.23 (± 0.35)), for (MODS) it was (1.47 (± 0.84)), for blood transfusion > 4 units it was (1.15 (± 0.41)), for surgical intervention it was (1.58 (± 0.51)) and for maternal death (1.39 (± 0.85)). SI ≥ 1.4, had sensitivity 26.82% (21.09-33.19); specificity 100%(99.53-100), PPV was 100% and NPV was 82.96%(81.8-84.06)with an AUC of 0.8 (0.78-0.83) on ROC analysis. In subjects with PIH/eclampsia, SI was lower and in patients with severe anemia, SI was higher.

Conclusion

SI performed well as a screening tool in the prediction of adverse maternal outcomes. SI ≥ 0.9 was significantly associated with maternal adverse outcomes: ICU admission, MODS, surgical intervention, blood transfusion and death. The study proposes an SI cut-off of 0.9 for referral and a cut-off of 1.1 for intervention in a tertiary care hospital. Patients with PIH/eclampsia tend to have lower mean SI values as compared to the rest of the study population, suggesting that SI may not be a reliable indicator in patients with PIH/eclampsia.

Importance of shock index in the evaluation of postpartum hemorrhage cases that necessitate blood transfusion

This study aims to determine cutoff values for shock index (SI) to predict the need for transfusion and composite adverse outcomes in postpartum hemorrhage (PPH) cases. One hundred thirty PPH cases (study group) that necessitated blood transfusion were retrospectively compared to a frequency-matched control group (n = 130). Receiver operating characteristic (ROC) curves and decision tree [Classification & Regression Tree (C&RT) and Chi-square Automatic Interaction Detector (CHAID)] were used to identify cutoff values for SI. Cutoff values for postdelivery, peak and delta SI values for the prediction of PPH that required transfusion were 0.9125 (0.815 sensitivity, 0.923 specificity), 0.9145 (0.892 sensitivity, 0.823 specificity) and 0.195 (0.823 sensitivity, 0.885 specificity), while cutoff values for the same SI values in the prediction of composite adverse outcome were 1.315 (0.645 sensitivity, 0.616 specificity), 1.183 (0.613 sensitivity, 0.737 specificity) and 0.487 (0.710 sensitivity, 0.758 specificity). Delta SI was superior to postdelivery and peak SI in the prediction of PPH that required transfusion. Peak SI was superior to postdelivery and delta SI in the prediction of composite adverse outcome. In conclusion, increased postdelivery, peak, and delta SI values were related to adverse outcomes for PPH. SI seems to be a practical and effective method for the objective assessment of postpartum hemorrhage.

Shock Index and Postpartum Hemorrhage in Vaginal Deliveries: A Multicenter Retrospective Study

INTRODUCTION

Shock index (SI), calculated by dividing heart rate by systolic blood pressure, is used to detect hemodynamic instability and hypovolemia. In obstetric practice, limited evidence is available regarding its usefulness in detecting postpartum hemorrhage (PPH). We aimed to evaluate the usefulness of SI in detecting PPH in vaginal deliveries using clinical data from 12 primary maternity care units in Japan.

MATERIAL AND METHODS

In this multicenter retrospective study, a total of 30,820 women who delivered vaginally at term at 12 primary maternity care units from January 2012 to December 2018 were included. Systolic and diastolic blood pressures and heart rate were measured at five different time points from admission to postpartum 2 h, and postpartum blood loss was measured. We evaluated the trend of average SI and the performance of each vital sign for detection of PPH.

RESULTS

The trend of average SI during labor and the immediate postpartum period was approximately 0.7 in women with blood loss of <500 mL. SI from the time of delivery of the placenta increased with an increase in blood loss. SI had the highest area under the receiver operating characteristic curve of 0.699 [95% confidence interval (CI), 0.682-0.716] and 0.758 (95% CI, 0.729-0.788) for PPH of ≥1,000 and ≥1,500 mL, respectively. However, both sensitivity of SI (1.0) for PPH (≥1,000 mL; 29.9%, and ≥1,500 mL; 40.5%, respectively) and correlation between maximum SI and blood loss (coefficient of correlation, 0.263) were low.

CONCLUSIONS

SI is a better parameter for PPH detection in vaginal deliveries than other vital signs. However, clinical judgment must incorporate other vital signs and symptoms associated with hypovolemic shock due to the low sensitivity of SI.

What is the normal range of obstetric shock index in the immediate postpartum period in a low-resource setting?

OBJECTIVE

To determine the normal range of shock index (SI), blood pressure (BP), mean arterial pressure (MAP) and heart rate (HR) among postpartum women in a low-resource setting.

METHODS

In a prospective cohort study, vital signs were recorded 1 hour after delivery among postpartum women with normal blood loss who delivered in Abakaliki, Nigeria, from April to July 2019.

RESULTS

Among 225 women, the median (95% reference range) was 120 (100-155.8), 70 (60-94), and 90 (66.5-116.6) mm Hg for systolic BP, diastolic BP, and MAP, respectively; 82 (65-102) bpm for HR; and 0.69 (0.48-0.89) for SI. The upper SI limit of 0.89 supported the current value of 0.9 as the upper limit; however, the lower SI limit of 0.48 corresponded to the current lower limit for a non-obstetric population (0.5). The SI of more than half of the study women (n=126; 56.0%) was within the normal range for non-obstetric women (0.5-0.7).

CONCLUSION

Although hemodynamic changes in pregnancy widen the SI range, 56.0% of women maintained SI within the non-obstetric reference range. In low-resource settings, the current normal obstetric SI range of 0.7-0.9 should be revised to 0.5-0.9 to accommodate this lower threshold.

The impact of maternal anemia and labor on the obstetric Shock Index in women in a developing country

Background

The Shock Index is a clinical tool to evaluate the hemodynamic status during hemorrhage. The impact of labor and pre-existing anaemia is unknown. The objective was to describe and discuss its clinical utility in this context.

Methods

This was a prospective cross-sectional study. The Shock Index (ratio between heart rate and systolic blood pressure) was measured in pregnant women at term, before or during labor. They were stratified according to the presence of anemia.

Results

The median Shock Index was significantly lower in women in labor than in those not in labor (0.72 (IQR: 0.64–0.83) vs. 0.85 (IQR: 0.80–0.94); p < 0.001). In women in labor, the Shock Index was not significantly different if anemia was present (0.72 (0.63–0.83) vs. 0.73 (0.65–0.82); p = 0.67).

Conclusions

Values of the Shock Index are affected by labor, which may hinder its utility in identifying hemorrhage during this period. However, the values were not altered by maternal anaemia. Therefore, an abnormal postpartum Shock Index should not be attributed to an abnormal antepartum Shock Index due to mild/moderate anemia.

Risk factors for postpartum sepsis: a nested case-control study

Background

The Majority (99%) of maternal deaths occur in low and middle-income countries. The three most important causes of maternal deaths in these regions are postpartum hemorrhage, pre-eclampsia and puerperal sepsis. There are several diagnostic criteria used to identify sepsis and one of the commonly used criteria is systematic inflammatory response syndrome (SIRS). However, these criteria require laboratory investigations that may not be feasible in resource-constrained settings. Therefore, this study aimed to develop a model based on risk factors and clinical signs and symptoms that can identify sepsis early among postpartum women.

Methods

A case-control study was nested in an ongoing cohort of 4000 postpartum women who delivered or were admitted to the study hospital. According to standard criteria of SIRS, 100 women with sepsis (cases) and 498 women without sepsis (controls) were recruited from January to July 2017. Information related to the socio-demographic status, antenatal care and use of tobacco were obtained via interview while pregnancy and delivery related information, comorbid and clinical sign and symptoms were retrieved from the ongoing cohort. Multivariable logistic regression was performed and discriminative performance of the model was assessed using area under the curve (AUC) of the receiver operating characteristic (ROC).

Results

Multivariable analysis revealed that 1–4 antenatal visits (95% CI 0.01–0.62).

, 3 or more vaginal examinations (95% CI 1.21–3.65), home delivery (95% CI 1.72–50.02), preterm delivery, diabetes in pregnancy (95% CI 1.93–20.23), lower abdominal pain (95% CI 1.15–3.42)) vaginal discharge (95% CI 2.97–20.21), SpO2 < 93% (95% CI 4.80–37.10) and blood glucose were significantly associated with sepsis. AUC was 0.84 (95% C.I 0.80–0.89) which indicated that risk factors and clinical sign and symptoms-based model has adequate ability to discriminate women with and without sepsis.

Conclusion

This study developed a non-invasive tool that can identify postpartum women with sepsis as accurately as SIRS criteria with good discriminative ability. Once validated, this tool has the potential to be scaled up for community use by frontline health care workers.