Transfusion Preparedness Strategies for Obstetric Hemorrhage: A Cost-Effectiveness Analysis

The suboptimal clinical applicability of prognostic prediction models for severe postpartum hemorrhage: a meta-epidemiological study

OBJECTIVES

To systematically investigate clinical applicability of the current prognostic prediction models for severe postpartum hemorrhage (SPPH).

STUDY DESIGN AND SETTING

A meta-epidemiological study of prognostic prediction models was conducted for SPPH. A pre-designed structured questionnaire was adopted to extract the study characteristics, predictors and the outcome, modeling methods, predictive performance, the classification ability for high-risk individuals, and clinical use scenarios. The risk of bias among studies was assessed by the Prediction model Risk Of Bias ASsessment Tool (PROBAST).

RESULTS

Twenty-two studies containing 27 prediction models were included. The number of predictors in the final models varied from 3 to 53. However, one-third of the models (11) did not clearly specify the timing of predictor measurement. Calibration was found to be lacking in 10 (37.0%) models. Among the 20 models with an incidence rate of predicted outcomes below 15.0%, none of the models estimated the area under the precision-recall curve, and all reported positive predictive values were below 40.0%. Only two (7.4%) models specified the target clinical setting, while seven (25.9%) models clarified the intended timing of model use. Lastly, all 22 studies were deemed to be at high risk of bias.

CONCLUSION

Current SPPH prediction models have limited clinical applicability due to methodological flaws, including unclear predictor measurement, inadequate calibration assessment, and insufficient evaluation of classification ability. Additionally, there is a lack of clarity regarding the timing for model use, target users, and clinical settings. These limitations raise concerns about the reliability and usefulness of these models in real-world clinical practice.

Validation of Three Models for Prediction of Blood Transfusion during Cesarean Delivery Admission

OBJECTIVE

 Prediction of blood transfusion during delivery admission allows for clinical preparedness and risk mitigation. Although prediction models have been developed and adopted into practice, their external validation is limited. We aimed to evaluate the performance of three blood transfusion prediction models in a U.S. cohort of individuals undergoing cesarean delivery.

STUDY DESIGN

 This was a secondary analysis of a multicenter randomized trial of tranexamic acid for prevention of hemorrhage at time of cesarean delivery. Three models were considered: a categorical risk tool (California Maternal Quality Care Collaborative [CMQCC]) and two regression models (Ahmadzia et al and Albright et al). The primary outcome was intrapartum or postpartum red blood cell transfusion. The CMQCC algorithm was applied to the cohort with frequency of risk category (low, medium, high) and associated transfusion rates reported. For the regression models, the area under the receiver-operating curve (AUC) was calculated and a calibration curve plotted to evaluate each model's capacity to predict receipt of transfusion. The regression model outputs were statistically compared.

RESULTS

 Of 10,785 analyzed individuals, 3.9% received a red blood cell transfusion during delivery admission. The CMQCC risk tool categorized 1,970 (18.3%) individuals as low risk, 5,259 (48.8%) as medium risk, and 3,556 (33.0%) as high risk with corresponding transfusion rates of 2.1% (95% confidence interval [CI]: 1.5-2.9%), 2.2% (95% CI: 1.8-2.6%), and 7.5% (95% CI: 6.6-8.4%), respectively. The AUC for prediction of blood transfusion using the Ahmadzia and Albright models was 0.78 (95% CI: 0.76-0.81) and 0.79 (95% CI: 0.77-0.82), respectively (p = 0.38 for difference). Calibration curves demonstrated overall agreement between the predicted probability and observed likelihood of blood transfusion.

CONCLUSION

 Three models were externally validated for prediction of blood transfusion during cesarean delivery admission in this U.S.

COHORT

Overall, performance was moderate; model selection should be based on ease of application until a specific model with superior predictive ability is developed.

KEY POINTS

· A total of 3.9% of individuals received a blood transfusion during cesarean delivery admission.. · Three models used in clinical practice are externally valid for blood transfusion prediction.. · Institutional model selection should be based on ease of application until further research identifies the optimal approach..

Cost-effectiveness of routine type and screens in select urological surgeries

PURPOSE

To evaluate the cost-effectiveness of obtaining a preoperative type and screen (T/S) for common urologic procedures.

METHODS

A decision tree model was constructed to track surgical patients undergoing two preoperative blood ordering strategies as follows: obtaining a preoperative T/S versus not doing so. The model was applied to the National (Nationwide) Inpatient Sample (NIS) data, from January 1, 2006 to September 30, 2015. Cost estimates for the model were created from combined patient-level data with published costs of a T/S, type and crossmatch (T/C), a unit of pRBC, and one unit of emergency-release transfusion (ERT). The primary outcome was the incremental cost per ERT prevented, expressed as an incremental cost-effectiveness ratio (ICER) between the two preoperative blood ordering strategies. A cost-effectiveness analysis determined the ICER of obtaining preoperative T/S to prevent an emergency-release transfusion (ERT), with a willingness-to-pay threshold of $1,500.00.

RESULTS

A total of 4,113,144 surgical admissions from 2006 to 2015 were reviewed. The overall transfusion rate was 10.54% (95% CI, 10.17-10.91) for all procedures. The ICER of preoperative T/S was $1500.00 per ERT prevented. One-way sensitivity analysis demonstrated that the risk of transfusion should exceed 4.12% to justify preoperative T/S.

CONCLUSION

Routine preoperative T/S for radical prostatectomy (rate = 3.88%) and penile implants (rate = .91%) does not represent a cost-effective practice for these surgeries. It is important for urologists to review their institution T/S policy to reduce inefficiencies within the preoperative setting.

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.

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.

Current State and Future Direction of Postpartum Hemorrhage Risk Assessment

In the United States, postpartum hemorrhage is a leading preventable cause of maternal mortality and morbidity. To reduce morbidity from postpartum hemorrhage, risk assessment is an important starting point for informing decisions about risk management and hemorrhage prevention. Current perinatal care guidelines from the Joint Commission recommend that all patients undergo postpartum hemorrhage risk assessment at admission and after delivery. Three maternal health organizations-the California Maternal Quality Care Collaborative, AWHONN, and the American College of Obstetricians and Gynecologists' Safe Motherhood Initiative-have developed postpartum hemorrhage risk-assessment tools for clinical use. Based on the presence of risk factors, each organization categorizes patients as low-, medium-, or high-risk, and ties pretransfusion testing recommendations to these categorizations. However, the accuracy of these tools' risk categorizations has come under increasing scrutiny. Given their low positive predictive value, the value proposition of pretransfusion testing in all patients classified as medium- and high-risk is low. Further, 40% of all postpartum hemorrhage events occur in low-risk patients, emphasizing the need for early vigilance and treatment regardless of categorization. We recommend that maternal health organizations consider alternatives to category-based risk tools for evaluating postpartum hemorrhage risk before delivery.

Transfusion Preparedness in the Labor and Delivery Unit: An Initiative to Improve Safety and Cost

OBJECTIVE

To evaluate patient safety, resource utilization, and transfusion-related cost after a policy change from universal type and screen to selective type and screen on admission to labor and delivery.

METHODS

Between October 2017 and September 2019, we performed a single-center implementation study focusing on risk-based type and screen instead of universal type and screen. Implementation of our policy was October 2018 and compared 1 year preimplementation with 1 year postimplementation. Patients were risk-stratified in alignment with California Maternal Quality Care Collaborative recommendations. Under the new policy, the blood bank holds a blood sample for processing (hold clot) on patients at low- and medium-risk of hemorrhage. Type and screen and crossmatch are obtained on high-risk patients or with a prior positive antibody screen. We collected patient outcomes, safety and cost data, and compliance and resource utilization metrics. Cost included direct costs of transfusion-related testing in the labor and delivery unit during the study period, from a health system perspective.

RESULTS

In 1 year postimplementation, there were no differences in emergency-release transfusion events (4 vs 3, P>.99). There were fewer emergency-release red blood cell (RBC) units transfused (9 vs 24, P=.002) and O-negative RBC units transfused (8 vs 18, P=.016) postimplementation compared with preimplementation. Hysterectomies (0.05% vs 0.1%, P=.44) and intensive care unit admissions (0.45% vs 0.51%, P=.43) were not different postimplementation compared with preimplementation. Postimplementation, mean monthly type and screen-related costs (ABO typing, antibody screen, and antibody workup costs) were lower, $9,753 compared with $20,676 in the preimplementation year, P<.001.

CONCLUSION

Implementation of selective type and screen policy in the labor and delivery unit was associated with projected annual savings of $181,000 in an institution with 4,000 deliveries per year, without evidence of increased maternal morbidity.

Validation of Postpartum Hemorrhage Admission Risk Factor Stratification in a Large Obstetrics Population

OBJECTIVE

This study aimed to evaluate the performance of the California Maternal Quality Care Collaborative (CMQCC) admission risk criteria for stratifying postpartum hemorrhage risk in a large obstetrics population.

STUDY DESIGN

Using detailed electronic health record data, we classified 261,964 delivery hospitalizations from Kaiser Permanente Northern California hospitals between 2010 and 2017 into high-, medium-, and low-risk groups based on CMQCC criteria. We used logistic regression to assess associations between CMQCC risk groups and postpartum hemorrhage using two different postpartum hemorrhage definitions, standard postpartum hemorrhage (blood loss ≥1,000 mL) and severe postpartum hemorrhage (based on transfusion, laboratory, and blood loss data). Among the low-risk group, we also evaluated associations between additional present-on-admission factors and severe postpartum hemorrhage.

RESULTS

Using the standard definition, postpartum hemorrhage occurred in approximately 5% of hospitalizations (n = 13,479), with a rate of 3.2, 10.5, and 10.2% in the low-, medium-, and high-risk groups. Severe postpartum hemorrhage occurred in 824 hospitalizations (0.3%), with a rate of 0.2, 0.5, and 1.3% in the low-, medium-, and high-risk groups. For either definition, the odds of postpartum hemorrhage were significantly higher in medium- and high-risk groups compared with the low-risk group. Over 40% of postpartum hemorrhages occurred in hospitalizations that were classified as low risk. Among the low-risk group, risk factors including hypertension and diabetes were associated with higher odds of severe postpartum hemorrhage.

CONCLUSION

We found that the CMQCC admission risk assessment criteria stratified women by increasing rates of severe postpartum hemorrhage in our sample, which enables early preparation for many postpartum hemorrhages. However, the CMQCC risk factors missed a substantial proportion of postpartum hemorrhages. Efforts to improve postpartum hemorrhage risk assessment using present-on-admission risk factors should consider inclusion of other nonobstetrical factors.

Cost of Elective Labor Induction Compared With Expectant Management in Nulliparous Women

OBJECTIVE

To compare the actual health-system cost of elective labor induction at 39 weeks of gestation with expectant management.

METHODS

This was an economic analysis of patients enrolled in the five Utah hospitals participating in a multicenter randomized trial of elective labor induction at 39 weeks of gestation compared with expectant management in low-risk nulliparous women. The entire trial enrolled more than 6,000 patients. For this subset, 1,201 had cost data available. The primary outcome was relative direct health care costs of maternal and neonatal care from a health system perspective. Secondary outcomes included the costs of each phase of maternal and neonatal care. Direct health system costs of maternal and neonatal care were measured using advanced costing analytics from the time of randomization at 38 weeks of gestation until exit from the study up to 8 weeks postpartum. Costs in each randomization arm were compared using generalized linear models and reported as the relative cost of induction compared with expectant management. With a fixed sample size, we had adequate power to detect a 7.3% or greater difference in overall costs.

RESULTS

The total cost of elective induction was no different than expectant management (mean difference +4.7%; 95% CI -2.1% to +12.0%; P=.18). Maternal outpatient antenatal care costs were 47.0% lower in the induction arm (95% CI -58.3% to -32.6%; P<.001). Maternal inpatient intrapartum and delivery care costs, conversely, were 16.9% higher among women undergoing labor induction (95% CI +5.5% to +29.5%; P=.003). Maternal inpatient postpartum care, maternal outpatient care after discharge, neonatal hospital care, and neonatal care after discharge did not differ between arms.

CONCLUSION

Total costs of elective labor induction and expectant management did not differ significantly. These results challenge the assumption that elective induction of labor leads to significant cost escalation.

Emergency-release blood transfusions after postpartum hemorrhage at the Intermountain Healthcare hospitals

BACKGROUND

Most low-risk obstetric patients do not have crossmatched blood available to treat unexpected postpartum hemorrhage. An emergency-release blood transfusion (ERBT) program is critical for hospitals with obstetrical services. We performed a retrospective analysis of obstetrical ERBTs administered in our multihospital system.

DESIGN AND METHODS

We collected data from the past 8 years at all Intermountain Healthcare hospitals on every ERBT after postpartum hemorrhage; logging circumstances, number and type of transfused products, and outcomes.

RESULTS

Eighty-nine women received ERBT following 224,035 live births, for an incidence of 3.97 transfused women/10,000 births. The most common causally-associated conditions were: uterine atony (40%), placental abruption/placenta previa (16%), retained placenta (11%), and uterine rupture (5%). The mean number of total units transfused was 7.9 (range 1-76). The mean number of red blood cells (RBCs) transfused was 4.8, the median 4, and SD was ±4.4. Massive transfusion protocols (MTPs) for trauma recommend using a ratio of 1:1:1 or 2:1:1 of RBC:FFP:Platelets, however the ratios varied widely for postpartum hemorrhage. Only 1.5% received a 1:1:1 ratio and 7.5% received a 2:1:1 ratio. Nineteen percent (17/89) of women underwent hysterectomy, 7% (6/89) had uterine artery embolization, 36% (32/89) had an intensive care unit admission, and 1% (1/89) died.

CONCLUSION

Emergency transfusion for postpartum hemorrhage occurred after 1/2500 births. Most women received less FFP and platelets than recommended for traumatic hemorrhage. A potentially better practice for postpartum hemorrhage would be a balanced ratio of blood products, transfusion of low-titer, group O, cold-stored, whole blood, or inclusion in a MTP.

Comparison of group O Rh(D)- red blood cell use in pregnant women across hospitals of various sizes and obstetric capabilities prior to the introduction of patient blood management guidelines

BACKGROUND

O Rh(D)- red blood cell (RBC) units can generally be transfused to most patients regardless of their ABO blood type and are frequently used during emergency situations. Detailed usage patterns of O Rh(D)- RBC units in obstetric populations have not been well characterised. With the introduction of patient blood management guidelines, historical usage patterns are important for providing comparative data.

AIMS

To determine how the use of O Rh(D)- RBC units in pregnant women differs between hospitals of different sizes and obstetric capabilities prior to patient blood management guidelines.

METHODS

Data from 67 New South Wales public hospital blood banks were linked with hospital and perinatal databases to identify RBC transfusions during pregnancy, birth and postnatally between July 2006 and December 2010. RBC transfusions were divided into O Rh(D)- or other blood types. Hospitals were classified according to birth volume, obstetric capability and location, with transfusions classified by timing and diagnosis.

RESULTS

Of the 12 078 RBC units transfused into pregnant women, 1062 (8.8%) were O Rh(D)-. Higher use of O Rh(D)- RBC units was seen in antenatal transfusions, preterm deliveries and in regional or smaller hospitals. There was wide variation in rates of O Rh(D)- RBC transfusion among hospitals.

CONCLUSIONS

The rate of O Rh(D)- RBC unit use in obstetrics was lower during the period assessed than the nationally reported usage. It is encouraging that O Rh(D)- RBCs were more commonly used in emergency or specialised situations, or in facilities where holding a large blood inventory is not feasible.

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.

Intraoperative Cell Salvage During Transurethral Resection of Prostate: A Case Report

Intraoperative cell salvage (ICS) became commercially available in 1968 and has enjoyed wide uptake. However, its use in transurethral resection of prostate (TURP) remains rare. We describe a 71-year-old man who underwent TURP with incomplete blood cross-matching. He suffered significant hemorrhage requiring return to theater. There was great delay in obtaining appropriately cross-matched blood, due to previous alloimmunization. ICS was used to retrieve blood present in bladder irrigation. This is the first Australian report of ICS use during TURP. This case led to a change in our practice and serves to demonstrate the potential of this technology during emergencies.