The association between the introduction of quantitative assessment of postpartum blood loss and institutional changes in clinical practice: an observational study

Quantitative blood loss measurement methods for early detection of primary postpartum haemorrhage following vaginal birth: A scoping review

AIM

To map the commonly used quantitative blood loss measurement methods in clinical practice and provide a solid foundation for future studies.

DESIGN AND METHOD

This study adhered to the JBI methodology for scoping reviews and preferred reporting items for systematic reviews and meta-analyses extension for scoping reviews. We conducted a literature search using five databases to retrieve articles published between January 2012 and September 2022. The search was repeated on 29 February 2024. Data extraction and verification were carried out by two independent researchers using a self-designed data extraction form.

RESULTS

Ultimately, 26 studies published between 2012 and 2024 were considered eligible for inclusion. Six categories of methods were identified from the 26 articles. Among the included studies, only two involved randomized controlled trials, with the majority being observational studies. The World Health Organization (2012) version of the postpartum haemorrhage diagnostic criteria was predominantly used in most studies. Gravimetric and volumetric methods emerged as the most commonly used methods for quantifying postpartum haemorrhages. The timing of blood collection was inconsistent among the included studies. Only 12 studies mentioned measures for the management of amniotic fluid.

CONCLUSIONS

This scoping review supports the replacement of the visual estimation of blood loss with quantitative assessment methods. Supporting a specific assessment approach is not feasible due to the variability of the study. Future research should focus on establishing the best practices for specific quantitative methods to standardize the management of postpartum haemorrhage and reduce the incidence of postpartum haemorrhage-related adverse outcomes.

RELEVANCE TO CLINICAL PRACTICE

Healthcare professionals need to acknowledge the low accuracy of visual estimation methods and implement quantitative methods to assess postpartum blood loss. Given the limitations inherent in each assessment method, quantification of blood loss should be combined with assessment of maternal vital signs, physiologic indicators and other factors.

Is There an Association between Platelet Count and Blood Loss in the Parturient? A Retrospective Study

OBJECTIVE

 The influence of thrombocytopenia on blood loss and postpartum hemorrhage (PPH) has been conflicting. Our aim was to determine if there is an association between predelivery platelet count and quantitative blood loss (QBL) and PPH in both vaginal (VD) and cesarean deliveries (CD).

STUDY DESIGN

 We conducted a retrospective database study at a single institution from April 1, 2017 to September 9, 2020. The platelet count closest to time of delivery and the QBL was assessed separately for VD and CD.

RESULTS

 A total of 22,479 records were reviewed, of which 16,822 (75%) were VD and 5,657 (25%) were CD. A total of 2,600 (12%) patients had thrombocytopenia, defined as a platelet count <150,000/mm3. Of these, 1,980 (76%) had a VD and 620 (24%) had CD. We found a statistically significant difference in QBL between parturients with thrombocytopenia compared with those without, with a median estimated difference in QBL of 25 (95% confidence interval [CI]: 16-32) and 57 mL (95% CI: 31-87) in VD and CD patients, respectively. We also found a statistically significant difference in QBL when comparing patients among all the platelet count ranges except in the lowest platelet count range of 50,000 to 69,999/mm3 with a mean difference of 52 (95% CI: 25-81) and 107 mL (95% CI: 39-180) in the VD and CD patients, respectively in the platelet count range of 70,000 to 99,999/mm3 . We also found the incidence of PPH was greater in those with thrombocytopenia, p < 0.001, but the median difference in QBL in all platelet groups was small.

CONCLUSION

 We found a statistically significant association between lower predelivery platelet counts and QBL and PPH. The clinical significance of these results is debatable, because at all platelet count ranges, differences in blood loss were small.

KEY POINTS

· Hemorrhage is etiology of morbidity and mortality in obstetric parturients.. · We found a small increase in blood loss in those with thrombocytopenia.. · The clinical relevance of these findings is debatable since the increased blood loss was small..

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.

Artificial Intelligence for Perioperative Medicine: Perioperative Intelligence

The anesthesiologist's role has expanded beyond the operating room, and anesthesiologist-led care teams can deliver coordinated care that spans the entire surgical experience, from preoperative optimization to long-term recovery of surgical patients. This expanded role can help reduce postoperative morbidity and mortality, which are regrettably common, unlike rare intraoperative mortality. Postoperative mortality, if considered a disease category, will be the third leading cause of death just after heart disease and cancer. Rapid advances in technologies like artificial intelligence provide an opportunity to build safe perioperative practices. Artificial intelligence helps by analyzing complex data across disparate systems and producing actionable information. Using artificial intelligence technologies, we can critically examine every aspect of perioperative medicine and devise innovative value-based solutions that can potentially improve patient safety and care delivery, while optimizing cost of care. In this narrative review, we discuss specific applications of artificial intelligence that may help advance all aspects of perioperative medicine, including clinical care, education, quality improvement, and research. We also discuss potential limitations of technology and provide our recommendations for successful adoption.

Optimizing systems to manage postpartum hemorrhage

Systems to optimize the management of postpartum hemorrhage must ensure timely diagnosis, rapid hemodynamic and hemostatic resuscitation, and prompt interventions to control the source of bleeding. None of these objectives can be effectively completed by a single clinician, and the management of postpartum hemorrhage requires a carefully coordinated interprofessional team. This article reviews systems designed to standardize hemorrhage diagnosis and response.

Effect of implementation of a colorimetric quantitative blood loss system for postpartum hemorrhage

OBJECTIVE

To evaluate if the implementation of a colorimetric quantitative blood loss (QBL) system during cesarean delivery improves clinical outcomes.

METHODS

We conducted a retrospective cohort analysis after cesarean section before and after implementation of the Triton based colorimetric QBL system. Prevalence of postpartum hemorrhage, amount of blood products transfused, length of hospitalization, and rates of intensive care unit (ICU) admission were compared.

RESULTS

A total of 2221 patients were included. There were 1192 patients in the pre-intervention group and 1029 patients in the post-intervention group. There was no significant difference between groups in the prevalence of postpartum hemorrhage (8.6% vs 9.3%, P = 0.57), amount of packed red blood cells (pRBCs) transfused (45 vs 30, P = 0.41) or average length of hospital stay in days (3.0 vs 3.0, P = 0.37). There was a statistically significant decrease in ICU admissions between the pre- and post-intervention groups (2.2% vs 1.0%, P = 0.02).

CONCLUSION

There was no effect of implementation of the colorimetric QBL application system on diagnosis of postpartum hemorrhage, amount of blood products transfused, or length of hospital stay. Although a significant decrease in ICU admissions was observed, we could not determine if these transfers were hemorrhage related.

Emergencies in obstetric anaesthesia: a narrative review

We conducted a narrative review in six areas of obstetric emergencies: category-1 caesarean section; difficult and failed airway; massive obstetric haemorrhage; hypertensive crisis; emergencies related to neuraxial anaesthesia; and maternal cardiac arrest. These areas represent significant research published within the last five years, with emphasis on large multicentre randomised trials, national or international practice guidelines and recommendations from major professional societies. Key topics discussed: prevention and management of failed neuraxial technique; role of high-flow nasal oxygenation and choice of neuromuscular drug in obstetric patients; prevention of accidental awareness during general anaesthesia; management of the difficult and failed obstetric airway; current perspectives on the use of tranexamic acid, fibrinogen concentrate and cell salvage; guidance on neuraxial placement in a thrombocytopenic obstetric patient; management of neuraxial drug errors, local anaesthetic systemic toxicity and unusually prolonged neuraxial block regression; and extracorporeal membrane oxygenation use in maternal cardiac arrest.

Comparing Postpartum Estimated and Quantified Blood Loss Among Racial Groups: An Observational Study

Objective: Racial and ethnic disparities in peripartum blood loss and postpartum hemorrhage (PPH) have not been adequately evaluated. We sought to compare postpartum blood loss and PPH in African American and Hispanic parturients compared to other groups.

Methods: This was a secondary analysis of an observational study at a tertiary academic center of a historical (August 2016 to January 2017) and interventional (August 2017 to January 2018) cohort of 7618 deliveries. Visual estimation of blood loss (EBL) was used in the historical group and quantitative blood loss (QBL) was implemented in the intervention group. Our primary endpoint was median blood loss in African Americans versus other racial groups between cohorts.

Results: A total of 7618 deliveries were evaluated; 755 (9.9%) were identified as African American with 1035 (13.6%) identifying as Hispanic. Blood loss was similar in racial groups using EBL (p=0.131), but not QBL that was 430 (227-771) in African Americans and 348 (200-612) in non-African Americans (p<0.001). PPH was greater among African Americans in both groups (10.3% vs. 6.9% in EBL cohort, p=0.023, and 16.9% vs. 11.6% in QBL cohort, p<0.001).

Conclusion: Racial and ethnic differences in peripartum blood loss were more apparent with QBL than EBL. It is unknown if these differences are caused by provider cognitive bias, socioeconomic differences, language barriers and/or other factors.

Latest advances in postpartum hemorrhage management

Hemorrhage is the leading cause of maternal mortality worldwide. A maternal health priority is improving how healthcare providers prevent and manage postpartum hemorrhage (PPH). Because anesthesiologists can help facilitate how hospitals develop approaches for PPH prevention and anticipatory planning, we review the potential utility of PPH risk-assessment tools, bundles, and protocols. Anesthesiologists rely on clinical and diagnostic information for initiating and evaluating medical management. Therefore, we review modalities for measuring blood loss after delivery, which includes visual, volumetric, gravimetric, and colorimetric approaches. Point-of-care technologies for assessing changes in central hemodynamics (ultrasonography) and coagulation profiles (rotational thromboelastometry and thromboelastography) are also discussed. Anesthesiologists play a critical role in the medical and transfusion management of PPH. Therefore, we review blood ordering and massive transfusion protocols, fixed-ratio vs. goal-directed transfusion approaches, coagulation changes during PPH, and the potential clinical utility of the pharmacological adjuncts, tranexamic acid, and fibrinogen concentrate.

The Role of Perinatal Nurses in the Use of Tranexamic Acid During Postpartum Hemorrhage

Postpartum hemorrhage (PPH) is a leading cause of maternal morbidity and mortality worldwide. Mitigation of PPH is dependent on identification of risk, readiness, timely identification of hemorrhage, accurate determination of blood loss, and effective treatment. Perinatal nurses must be prepared to participate in all these aspects of care, including the use of tranexamic acid, an antifibrinolytic agent that has more recently been added to the pharmacologic agents used to reduce blood loss associated with hemorrhage. The purpose of this article is to identify the nurse's role in the management of PPH and to introduce the use of tranexamic acid in PPH management as part of the nurse's role in implementing best practices for PPH.

Limitations of Gravimetric Quantitative Blood Loss during Cesarean Delivery

Objective  This study examined the accuracy, sources of error, and limitations of gravimetric quantification of blood loss (QBL) during cesarean delivery. Study Design  Blood loss determined by assays of the hemoglobin content on surgical sponges and in suction canisters was compared with QBL in 50 parturients. Results  QBL was moderately correlated to the actual blood loss ( r  = 0.564; p  < 0.001). Compared with the reference assay, QBL overestimated blood loss for 44 patients (88%). QBL deviated from the assayed blood loss by more than 250 mL in 34 patients (68%) and by more than 500 mL in 16 cases (32%). Assayed blood loss was more than 1,000 mL in four patients. For three of these patients, QBL was more than 1,000 mL (sensitivity = 75%). QBL was more than 1,000 mL in 12 patients. While three of these had an assayed blood loss of more than 1,000 mL, 9 of the 46 patients with blood losses of less than 1,000 mL by the assay (20%) were incorrectly identified as having postpartum hemorrhage by QBL (false positives). The specificity of quantitative QBL for detection of blood loss more than or equal to 1,000 mL was 80.4%. Conclusion  QBL was only moderately correlated with the reference assay. While overestimation was more common than underestimation, both occurred. Moreover, QBL was particularly inaccurate when substantial bleeding occurred. Key Points QBL is inaccurate in cesarean delivery.QBL deviated from the assay result by more than 500 mL in 32% of cases.QBL sensitivity and specificity for hemorrhage is 75.0% (95% confidence interval [CI]: 0.19-0.93) and 80.4% (95% CI: 0.69-0.92), respectively.

Postpartum hemorrhage: Moving from response to prevention for Alaska Native mothers

OBJECTIVE

To identify risk factors for postpartum hemorrhage in a population of Alaska Native women.

METHODS

A case-control study of 384 women (128 cases, 256 controls) delivering between August 1, 2018, and July 31, 2019, was conducted at a Level III maternal referral center for Alaska Native women in Alaska. Risk factors were assessed via retrospective chart review, and bivariate and conditional regression analyses were conducted to determine odds ratios (ORs) between women with and without postpartum hemorrhage.

RESULTS

Body mass index ≥40 (OR 2.6, 95% confidence interval [CI] 1.4-4.5), antepartum bleeding (OR 6.3, 95% CI 1.2-31.6), previous postpartum hemorrhage (OR 5, 95% CI 2.6-9.8), suspected macrosomia (OR 2.7, 95% CI 1.4-5.3), macrosomia with birthweight ≥4000 g (OR 3.1, 95% CI 1.8-5.3), pre-eclampsia with magnesium sulfate (OR 4.0, 95% CI 2.0-8.0), length of third stage of labor >20 min (OR 2.2, 95% CI 1.1-4.4), oxytocin use >12 h (OR 5.4, 95% CI 2.0-14.6), residence in a rural community (OR 2.2, 95% CI 1.4-3.6), and vitamin D supplementation (OR 1.7, 95% CI 1.1-2.6) were associated with greater risk of postpartum hemorrhage.

CONCLUSION

Analysis of clinical and geographic risk factors for postpartum hemorrhage in Alaska Native women identified important targets for prevention.

Meeting the New Joint Commission's Maternal Safety Requirements: A Quantitative Blood Loss Train-the-Trainer Program for Improved Process and Outcomes

INTRODUCTION

Recently, the American College of Obstetricians and Gynecologists Committee on Obstetric Practice encouraged the use of quantitative and cumulative assessment of maternal blood loss (QBL) as part of safety bundles for prevention of postpartum hemorrhage. The aim of this study was to determine whether our train-the-trainer QBL program improved process and patient outcomes.

METHODS

In this pre-post interventional study, 26 "champions" participated in the QBL train-the-trainer program in preparation for patient safety bundle rollout. The multipart program included at least 3 simulated C-section hemorrhage scenarios and rapid-cycle debriefing. Champions used the curriculum for broad staff training for 2 months before safety bundle implementation.Six months each of preintervention and postintervention data were collected from medical records of all qualified cases (N = 4413). Process outcomes were evaluated by comparing number of women who received QBL. Patient outcomes were evaluated by comparing blood transfusion rates and number of morbid cases (≥4 packed red blood cell units). χ2 test was used for analyses.

RESULTS

Review of medical records indicated that 99.8% of 2218 women received QBL posttraining compared with 16.6% of 2195 women receiving QBL before training (P = 0.0001.) Transfusion rates increased from 54.47 to 69.25 units/1000 mothers. The rate of morbid cases (≥4 red blood cell units) dropped from 2.13 to 0.48 cases/1000 mothers.

CONCLUSIONS

Our findings suggest the train-the-trainer QBL program was associated with improved process and decreased morbidity when implemented with a hemorrhage safety bundle. Further research is required to examine components of simulation-based QBL training methods and implementation to evaluate their impact on clinical outcomes.

Can measuring blood loss at delivery reduce hemorrhage-related morbidity?

Quantitation of blood loss after vaginal and cesarean delivery has been advocated for the timely detection of postpartum hemorrhage and activation of protocols for resuscitation. Morbidity and mortality from postpartum hemorrhage is considered to be largely preventable and is attributed to delayed recognition with under-resuscitation or inappropriate resuscitation. Optimizing detection of postpartum hemorrhage through refining how blood loss is measured is therefore clinically relevant. In this review on quantitative blood loss for postpartum hemorrhage, recent advances in the methods used to quantitate blood loss will be reviewed, with a comparison of utility and precision for blood loss measurement after vaginal and cesarean delivery. Considerations for the implementation of a quantitative blood loss system on the labor and delivery unit, including its benefits and challenges, will be discussed. The existing evidence for impact of blood loss quantitation in obstetrics on hemorrhage-related morbidity will be delineated, along with knowledge gaps and future research priorities.

Quantification of Blood Loss Improves Detection of Postpartum Hemorrhage and Accuracy of Postpartum Hemorrhage Rates: A Retrospective Cohort Study

Objective To evaluate the ability of estimated blood loss (EBL) and quantitative blood loss (QBL) to predict the need for blood transfusion in postpartum patients. Methods This is a retrospective observational study involving all deliveries one year before and after the change from EBL to QBL assessment in June 2017. Blood loss, need for blood transfusion, admission hematocrit, and postpartum nadir hematocrit were collected. Descriptive and bivariable analyses were performed. Receiver operator curves were compared. Results Overall, the baseline characteristics between the EBL (n=2743) and QBL (n=2,712) groups were similar. Although there was a higher rate of blood loss ≥ 1,000 mL in QBL vs EBL (6.5% vs 2.1%, P<0.001), there was no difference in the rate of blood transfusions (2.0% vs 2.0%, P=1). Among cesarean deliveries, QBL outperformed EBL for predicting blood transfusion and/or ≥10 point drop in hematocrit (AUC 0.75 vs 0.66, P=0.02). QBL also outperformed EBL for predicting transfusion after vaginal delivery (AUC 0.93 vs 0.81, P=0.03).  Conclusion QBL is a more sensitive test for detecting clinically significant blood loss, which could lead to earlier recognition of hemorrhage and interventions.

Maternal safety: recent advances and implications for the obstetric anesthesiologist

PURPOSE OF REVIEW

Recognition of the increasing maternal mortality rate in the United States has been accompanied by intense efforts to improve maternal safety. This article reviews recent advances in maternal safety, highlighting those of particular relevance to anesthesiologists.

RECENT FINDINGS

Cardiovascular and other chronic medical conditions contribute to an increasing number of maternal deaths. Anesthetic complications associated with general anesthesia are decreasing, but complications associated with neuraxial techniques persist. Obstetric early warning systems are evolving and hold promise in identifying women at risk for adverse intrapartum events. Postpartum hemorrhage rates are rising, and rigorous evaluation of existing protocols may reveal unrecognized deficiencies. Development of regionalized centers for high-risk maternity care is a promising strategy to match women at risk for adverse events with appropriate resources. Opioids are a growing threat to maternal safety. There is growing evidence for racial inequities and health disparities in maternal morbidity and mortality.

SUMMARY

Anesthesiologists play an essential role in ensuring maternal safety. While continued intrapartum vigilance is appropriate, addressing the full spectrum of contributors to maternal mortality, including those with larger roles beyond the immediate peripartum time period, will be essential to ongoing efforts to improve maternal safety.

Introduction of standardized, cumulative quantitative measurement of blood loss into routine maternity care

Introduction: Postpartum hemorrhage (PPH) is the leading cause of maternal morbidity in the UK. Visual estimation of blood loss is unreliable yet remains common practice. As part of a national quality improvement project to improve care during PPH, standardized, quantitative measurement of blood loss (QBL) for all deliveries was introduced into a tertiary obstetric unit in Cardiff, Wales.Methods: Retrospective analysis of 875 consecutive maternities between December 2017 and February 2018 was undertaken. Of these, 372 mothers had both pre- and post-partum hemoglobin (Hb) were recorded. Regression analyses were performed to investigate the relationship between change in Hb adjusted for red cell transfusion and QBL.Results: The correlation coefficient between QBL and adjusted change in Hb for all deliveries (n = 372) was 0.57. This corresponded to an estimated fall of adjusted change in Hb of 15.3 g/L (95% CI: 13.1, 17.6) per 1000 mL blood loss.Discussion: QBL has been shown to be reliable across all maternity settings, with reproducible results in theater and delivery rooms (on the obstetric unit and alongside midwifery-led unit). QBL is moderately correlated with adjusted change in Hb for all volumes of bleeding and gives clinicians more accurate knowledge of blood loss than visual estimation. This low-cost, low-fidelity intervention can influence the timely escalation of clinical care and therefore patient outcome.

Management of cesarean delivery in a parturient with sickle cell disease

Chronic hemolysis and intermittent vaso-occlusion in sickle cell disease can lead to recurrent blood transfusions with related complications such as antibody formation and rarely, life-threatening reactions. We report a case of a parturient who presented with complications of sickle cell disease and who later had fetal compromise that required an emergent cesarean delivery. Complex management decisions were made, aided by technologies such as rotational thromboelastometry, quantitative blood loss analysis and cell salvage.

Management of post-partum hemorrhage and the role of the obstetric anesthesiologist

PURPOSE OF REVIEW

The landscape of post-partum hemorrhage management is rapidly changing. Modifications to definitions, bundles, and care plans occur frequently with management strategies becoming more complex. It has become apparent that the management of these patients requires a multidisciplinary approach with the involvement of obstetricians, anesthesiologists, gynecologist/oncologists, nursing, and care associates. This review article is meant to be an evidence-based review of post-partum hemorrhage with practical recommendations and a look at future directions of the management of post-partum hemorrhage from the vantage point of the obstetric anesthesiologist in an effort to enhance the collaborative treatment of this at risk population.