Editor: Deborah Sesok-Pizzini, MD, MBA, chief medical officer, Labcorp Diagnostics, Burlington, NC, and adjunct professor, Department of Clinical Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia.
Analysis of hospital length of stay and cost savings using an in-house HIT antibody assay
June 2024—In today’s health care environment, clinical laboratories increasingly must focus on test optimization, or generating quality patient care in a timely manner while controlling costs. A metric that can assist with test optimization is turnaround time (TAT), the reduction of which can lead to earlier diagnosis and treatment. Conducting assays in house is one way to potentially reduce TAT. Laboratories often use test volume and the cost of reagents, equipment, and personnel to determine the benefit of bringing an assay in house. However, it is important not to overlook the impact and costs that extend beyond the laboratory with regard to patient care and potential savings from improved care. Heparin-induced thrombocytopenia (HIT) is a life-threatening condition caused by developing antibodies against a complex of heparin and platelet factor 4 (PF4), resulting in activation of platelets and endothelial cells. HIT often causes a sudden drop in platelet count, with a simultaneous risk of thrombosis. The mortality rates associated with a diagnosis of HIT are as high as 20 percent. The serotonin release assay (SRA) is the gold standard for diagnosing HIT, but the test is most often performed in a commercial reference laboratory. Another assay involved in early diagnostic screening is the PF4/polyanion ELISA for detecting anti-PF4 antibodies. The Hemosil (Werfen, Bedford, Mass.) automated platform to test for HIT antibodies was introduced in 2017. It has a higher positive predictive value than ELISA and a sensitivity of 97.4 percent and specificity of up to 94 percent. The authors conducted a study to determine how bringing the Hemosil HIT antibody assay in house impacts the metric of hospital length of stay (LOS). They performed a retrospective review of patient visits, during a seven-year period, in which HIT antibody assays were conducted. The authors then determined the mean LOS for send-out versus in-house HIT antibody assay cohorts that comprised patients with positive and negative results. They analyzed their health systemwide mean LOS and metrics of acuity and performed a financial analysis of the estimated cost savings from bringing the HIT assay in house. The results showed a mean reduction in LOS of 3.97 days for the in-house cohort. The reduction was driven primarily by a decrease in LOS among patients with a negative HIT antibody assay result. Bringing the HIT assay in house generated an estimated cost savings of $3.9 million over the three years and 10 months that it was conducted in house and an estimated mean savings per patient of $7,305 during the same timeframe, despite an increase in health care costs over time. This study demonstrated the value and impact of test optimization outside of the traditional laboratory metrics of test volume and costs. Focusing on the metric of LOS showed the positive impact on patient care generated by bringing the HIT assay in house. There was no evidence that the reduction in LOS was due to other systemwide initiatives or a decline in patient acuity. The authors found that the reduction in HIT antibody assay TAT accounted for 67 percent of the reduction in LOS. They proposed that this was due to a synergistic effect resulting from the institution’s coagulation diagnostic management team being able to act earlier on the test information from an HIT diagnosis.
Raymond C, O’Rourke M, Dell’Osso L, et al. Analysis of hospital length of stay and cost savings with an in-house heparin-induced thrombocytopenia antibody assay at a midsized institution. Am J Clin Pathol. 2024;161:349–359.
Correspondence: Dr. Christopher Zahner at cjzahner@utmb.edu
Use of cryoprecipitate to treat life-threatening hemorrhage in children
Life-threatening hemorrhage in children can have multiple etiologies, including trauma, perioperative bleeding, gastrointestinal bleeding, and disseminated intravascular coagulation. Trauma is the most common cause of death in children younger than one year of age, according to the Centers for Disease Control and Prevention, and death from traumatic hemorrhagic shock typically occurs within the first six hours of injury. The Massive Transfusion in Children (MATIC) study showed that while trauma was the most common cause of life-threatening bleeding, a comparable proportion of children had surgical bleeding or medical illness. To address this type of life-threatening hemorrhage (LTH), many investigators are studying damage-control resuscitation strategies and avoiding hemodilution by transfusing whole blood or red blood cells, plasma, and platelets in a 1:1:1 unit ratio or using products containing large amounts of fibrinogen, such as fibrinogen concentrates or cryoprecipitate. While cryoprecipitate and fibrinogen concentrates may be given to critically ill children in the setting of surgery, trauma, or medical illness, there is insufficient data on how cryoprecipitate transfusions impact outcomes in children with LTH. The authors hypothesized that children who received cryoprecipitate in the setting of LTH would have improved mortality at 24 hours compared with children who did not receive cryoprecipitate. They performed a secondary analysis of the MATIC multicenter prospective observational study of children with LTH, ages birth to 17 years. These children received more than 40 mL/kg of total blood products over six hours or were transfused under massive transfusion protocol activation. The patients were categorized into transfusion or no transfusion of cryoprecipitate during their resuscitation and based on whether their bleeding was from trauma or from operative or medical causes. The authors performed a bivariate analysis to identify variables that were associated with six-hour, 24-hour, and 28-day mortality. They also used a Cox hazard regression model to adjust for potential confounders in the data. The results showed that cryoprecipitate was transfused to 33.9 percent (152 of 449) of children during LTH. The median time (interquartile range) to cryoprecipitate administration was 108 (47–212) minutes. The children receiving cryoprecipitate transfusions were younger, more often female, and had higher body mass index and pre-LTH PRISM (Pediatric Risk of Mortality III) scores and lower platelet counts. Of interest, cryoprecipitate administration was independently associated with lower six-hour mortality (hazard ratio, 0.41 [95 percent confidence interval, 0.19–0.89]; P=.02) and 24-hour mortality (hazard ratio, 0.46 [95 percent confidence interval, 0.24–0.89]; P=.02) after adjusting for PRISM score, bleeding etiology, age, gender, RBC volume, platelet volume, antifibrinolytic use, and cardiac arrest. However, no differences in 28-day mortality were noted between the study groups. The authors suggested that this may have been due to other disease processes or therapeutic interventions contributing to the 28-day mortality results. The authors showed in this secondary analysis of MATIC data that cryoprecipitate transfusion of children with LTH early in resuscitation was associated with reduced early mortality. They noted that additional prospective randomized trials are needed to assess whether cryoprecipitate can improve survival after LTH. Additional platform clinical trials may help demonstrate which combinations of therapies are effective and safe in children with LTH.
Horst JA, Spinella PC, Leonard JC, et al. Cryoprecipitate for the treatment of life-threatening hemorrhage in children. Transfusion. 2023;63:S10–S27. doi:10.1111/trf.17340
Correspondence: Dr. Jennifer A. Horst at jhorst@wustl.edu