Minimizing cost associated with management of heparin-induced thrombocytopenia: A cost analysis of various laboratory testing models.

INTRODUCTION: Management of patients with suspected heparin-induced thrombocytopenia (HIT) can lead to significant costs. Reported cost-saving initiatives have focused on minimizing inappropriate testing in low-risk patients and optimizing alternative anticoagulant selection. We sought to further investigate how utilizing various HIT laboratory testing models would impact total cost of testing and alternative anticoagulant use. METHODS: Utilizing a retrospective cohort of adult patients tested for HIT over three years within our institution, we evaluated how utilization of four distinct laboratory models impacted total number of HIT test combinations completed, time to HIT testing finalization, percentage of patients discharged from the hospital prior to HIT testing finalization, total alternative anticoagulant days, and total anticipated major bleed events. Additionally, we calculated cost of laboratory testing and alternative anticoagulant associated with each model. RESULTS: A total of 482 patients were included in our cohort. A laboratory testing model that utilized an in-house platelet factor 4 (PF4)-heparin enzyme-linked immunosorbent assay (ELISA) completed three days weekly, and reflex serotonin release assay (SRA) with a five-day turnaround resulted in the shortest mean time to HIT testing finalization, lowest percentage of patients discharged prior to HIT testing finalization, and lowest total alternative anticoagulant days. CONCLUSIONS: Institutions should evaluate current HIT laboratory testing practices and assess for opportunities for optimization. Testing models utilizing a PF4-heparin antibody ELISA with a reflex SRA for positive results may improve testing metrics and lead to lower utilization of alternative anticoagulants.

Implementing thrombelastography: Experiences from a level I trauma institution.

Viscoelastic hemostatic assays such as thrombelastography (TEG) and rotational thrombelastometry have proven to be important point-of-care tools in the management of acute traumatic hemorrhage. Despite the availability of prospective studies that have confirmed the utility of TEG in reducing transfusion requirements and mortality in bleeding patients when compared to conventional coagulation tests, many institutions run into barriers implementing these viscoelastic hemostatic assays due to concerns regarding cost and benefit. At our academic Level 1 trauma institution, the Division of Trauma, Critical Care, and Acute Care Surgery advocated for the addition of TEG to the clinical armamentarium of providers caring for injured patients and thus spearheaded the clinical implementation of TEG. With the approval of the central laboratory, the Division developed an extensive and well-trained team to run and interpret TEGs as well as perform machine validation and upkeep. The Division continues to perform point-of-care testing throughout the hospital today.

Simple Laboratory Test Utilization Interventions to Reduce Inappropriate Specialty Coagulation Testing.

OBJECTIVES: The naming convention in coagulation may cause confusion in electronic ordering systems, leading to inappropriate test orders. We implemented test utilization efforts and studied utilization before and after interventions for two specialty coagulation assays. METHODS: Two interventions were implemented: test names were changed from factor assay to activity, and residents reviewed all factor V and X requests. A retrospective review of factor V and X activity orders was performed for the period 1 year before and after interventions. RESULTS: After interventions, factor V and X activity orders decreased by approximately 40%. Resulted tests decreased by 53.8% and 47.8%, corresponding to reductions of $2,493.05 and $1,867.80 per year in laboratory charges for factor V and factor X activity, respectively. Abnormal factor V activity results increased from 45% to 59%. Factor V activity orders from outpatient clinics decreased by 21.6%. CONCLUSIONS: Simple interventions can reduce inappropriate specialty coagulation test orders and unnecessary costs.

A cost-effective approach to factor assay calibration using a truncated live calibration curve.

INTRODUCTION: The measurements of clotting factor activities are usually performed using a one-stage clotting assay (OSA) or chromogenic substrate assay (CSA). Advances in automated coagulation analysers have led to the utilization of stored calibration curves. There are sometimes substantial intervals between test calibration and analysis of samples. Variability in results can be influenced by calibrant and methodology. Several guidelines recommend calibration and patient samples be performed together in parallel; this incurs costs, but reliance on a stored calibration curve may lead to inaccuracy of results over time. METHODS: We evaluated inclusion of a live truncated (3 point) calibration curve using calibrator plasma alongside test samples and compared results calculated against the stored calibration curves and live truncated calibration to assess the impact on precision and accuracy. The feasibility of this was tested on two hospital sites in the UK; OSA and CSA were performed on Sysmex CS5100 using Actin FS, SynthASil, Innovin, Biophen chromogenic VIII and Rossix chromogenic IX. RESULTS: Results of two batches of IQC were compared for FII, FV, FVII, FX, FIX:C, FXI, FXII and OSA FVIII (FVIII:C1) and CSA FVIII:C (FVIII:CR) and FXI:C. By utilizing a live truncated calibration, precision improved with the most striking examples: FXII %CV 23.1% to 3.1% (site A) FXI 7.3% to 2.4% (site B). The improvement in other clotting factors was more modest. CONCLUSION: To the best of our knowledge, this is the first study that demonstrates that the use of a live truncated calibration curve will improve precision and accuracy.

Filling accuracy and imprecision of commercial evacuated sodium citrate coagulation tubes.

Current recommendations advocate that blood tubes for coagulation testing should be filled not less than 90% of their nominal filling volume, since under- or over-filling >10% may generate unreliable results of some hemostasis assays. This study was hence aimed to explore filling accuracy and precision of commercial blood tubes. Between-lot variations of 3 different lots (20 tubes per lot) of 3.2% citrate blood tubes manufactured by Becton Dickinson, Greiner and Kima were studied. One additional lot from each manufacturer was assessed in triplicate (three series of 20 tubes), to assess within-lot variation. All tubes were first weighed empty and then filled with distilled water by a syringe, under ideal filling conditions. Filled tubes were weighed again, in duplicate. For each 20 tubes series, mean bias (deviation from the ideal tube filling volume) and imprecision (coefficient of variation; CV%) were calculated. All biases were within ±10%. Within-lot and between-lot variation in filling volume was acceptable, and comprised between 0.4 and 2.4%. Greiner tubes were the most accurate (bias, -1.0 to 2.4%), followed by Kima (bias, -7.8 to -5.9%) and Becton Dickinson (bias, -9.6 to 3.3%) tubes. The highest between-lot difference was noted for Becton Dickinson tubes (up to 12.9%), followed by Greiner and Kima tubes (up to 3.4 and 1.8%, respectively). Although coagulation tubes filling accuracy was within ±10% for all three tested manufacturers, the overall bias was found to be variable among manufacturers and lots. Major effort shall be made by blood tube manufacturers for improving standardization of their products.

An Audit of Thrombophilia Testing in Patients with Ischemic Stroke or Transient Ischemic Attack: The Futility of Testing.

OBJECTIVES: Many patients admitted with an ischemic stroke or transient ischemic attack (TIA) undergo thrombophilia testing. There is limited evidence to support this practice. We examined the effect of thrombophilia testing on management of patients admitted with an ischemic stroke or TIA. MATERIALS AND METHODS: In this retrospective observational single-center study, we identified patients who were admitted with stroke or TIA and underwent thrombophilia testing over a 45-month period. We reviewed their electronic medical records to assess whether testing affected clinical management, defined as anticoagulation treatment by the time of discharge due to a positive test result. Secondary endpoints included potential misdiagnosis due to false positive results and cost of testing. RESULTS: Testing was performed in 143 patients with a stroke or TIA. Forty-four patients (31%) had at least 1 positive test result. The most common positive tests were an elevated factor VIII activity (18% of patients tested) and decreased protein S activity (11% of patients tested). Both of these tests are subject to acute phase effects. Testing altered clinical management in only 1 patient (1% of total patients tested). Thirty-three patients (75%) have the potential for carrying a misdiagnosis due to a positive test that was never repeated for confirmation or repeated too soon after the initial positive test. The annual cost of testing was approximately $62,000. CONCLUSIONS: Thrombophilia testing in the acute inpatient setting rarely impacted the clinical management of patients admitted with a stroke or TIA. By avoiding thrombophilia testing, both the potential for misdiagnosis and health care costs can be reduced. Therefore, we have discontinued thrombophilia testing in in-patients with a diagnosis of stroke.

Reducing the use of inappropriate coagulation testing in emergency general surgical patients.

Background and aims Indiscriminate coagulation testing in emergency general surgical patients can lead to inappropriate delay in surgery, cause unnecessary concern and is associated with significant cost. The British Committee for Standards in Haematology recommends against coagulation testing to predict peri-operative bleeding risk in unselected patients. Our aim was to assess the appropriateness of coagulation tests performed in emergency general surgical patients and evaluate the effect of a series of educational interventions on clinical practice. Methods and results Appropriate indications for performing coagulation testing included a positive bleeding history, the presence of liver disease/cholestasis, sepsis or use of anticoagulants. Initial data on 142 patients were collected over 2 weeks of receiving. Following analysis, indications for appropriate coagulation testing were highlighted and data were collected on a further 190 patients. Comparing the audit cycles, we observed a decrease in the proportion of patients who underwent routine testing (49.3% vs 32.6%; p = 0.002) and inappropriate testing (67% of tests vs 34% of tests; p < 0.001). Despite being highlighted, there was no evidence of improved documentation of bleeding histories on admission. Conclusions This observational study suggests that simple educational messages can reduce the inappropriate use of coagulation screening tests in general surgical emergencies. This seems to result from clarification of the appropriate surgical indications for coagulation testing in this group.

Accuracy, reproducibility and costs of different laboratory assays for the monitoring of unfractionated heparin in clinical practice: a prospective evaluation study and survey among Swiss institutions.

OBJECTIVES: To investigate the accuracy, reproducibility and costs of different laboratory assays for the monitoring of unfractionated heparin (UFH) in clinical practice and to study test utilisation in Switzerland. DESIGN: Prospective evaluation study and survey among Swiss hospitals and laboratories. SETTING: Secondary care hospital in rural Switzerland (evaluation study); all Swiss hospitals and laboratories (survey). PARTICIPANTS: All consecutive patients, monitored for treatment with UFH during two time periods, were included (May to July 2014 and January to February 2015; n=254). OUTCOME MEASURES: Results of activated partial thromboplastin time (aPTT), thrombin time (TT), prothrombinase-induced clotting time (PiCT) and anti-Xa activity with respect to UFH concentration RESULTS: Spearman's correlation coefficient (rs) with regard to anti-Xa activity was 0.68 (95% CI 0.60 to 0.75) for aPTT, 0.79 (0.69 to 0.86) for TT and 0.94 (0.93 to 0.95) for PiCT. The correlation (rs) between anti-Xa activity and heparin concentration as determined by spiking plasma samples was 1.0 (1.0 to 1.0). The coefficient of variation was at most 5% for PiCT and anti-Xa activity (within-run as well as day-to-day variability). The total costs per test in Swiss Francs (SFr) were SFr23.40 for aPTT, SFr33.30 for TT, SFr15.70 for PiCT and SFr24.15 for anti-Xa activity. The various tests were employed in Swiss institutions with the following frequencies: aPTT 53.2%, TT 21.6%, anti-Xa activity 7.2%, PiCT 1.4%; 16.6% of hospitals performed more than one test. CONCLUSIONS: The accuracy and reproducibility of PiCT and anti-Xa activity for monitoring of UFH was superior, and analytical costs were equivalent to or lower than aPTT and TT.

Repeating Critical Hematology and Coagulation Values Wastes Resources, Lengthens Turnaround Time, and Delays Clinical Action.

OBJECTIVES: To determine the need and impact of repeating critical values in hematology and coagulation. METHODS: We prospectively evaluated the need for repeating critical values. The cost of this practice was estimated using a workflow analysis. Retrospective chart review before and after removal of this process was performed to assess the clinical impact of removing this practice. RESULTS: Over 95% of the repeated values remained critical and all but one of the repeats were within the expected analytical precision of the assays. The practice of repeating critical values delayed turnaround time for these results and wasted resources, most notably manpower. The delay associated with repeating hematology critical values resulted in delayed administration of blood product (RBC units). CONCLUSIONS: Repeating critical hematology and coagulation results was found to be an unnecessary process that wasted laboratory resources and lengthened turnaround time, delaying clinical intervention.

Overuse of preoperative laboratory coagulation testing and ABO blood typing: a French national study.

Background: Following publication of guidelines on routine preoperative tests, the French Society of Anaesthesiology and Intensive Care (SFAR), in association with French national public health insurance, conducted a survey to evaluate adherence to guidelines and the economic consequences. Methods: Using the French Hospital Discharge Database and National Health Insurance Information system, tests performed during the 30 days before surgery were analysed for two situations: (1) standard laboratory coagulation tests and ABO blood typing in children able to walk and scheduled for tonsillectomy/adenoidectomy; and (2) ABO blood typing in adults before laparoscopic cholecystectomy, thyroidectomy, lumbar discectomy or breast surgery. Guidelines do not recommend any preoperative tests in these settings. Results: Between 2013 and 2015, a coagulation test was performed in 49% of the 241 017 children who underwent tonsillectomy and 39% of the 133 790 children who underwent adenoidectomy. A similar pattern was observed for ABO blood typing although re-operation rates for bleeding on the first postoperative day were very low (0.12-0.31% for tonsillectomy and 0.01-0.02% for adenoidectomy). Between 2012 and 2015, ABO blood typing was performed in 32-45% of the 1 114 082 patients who underwent one of the four selected procedures. The transfusion rate was very low (0.02-0.31%). The mean cost for the four procedures over the 4 yr period was €5 310 000 (sd €325 000). Conclusions: Standard laboratory coagulation tests and ABO blood typing are still routinely prescribed before surgery and anaesthesia despite current guidelines. This over-prescription represents a high and unnecessary cost, and should therefore be addressed.

Rotational Thromboelastometry or Conventional Coagulation Tests in Liver Transplantation: Comparing Blood Loss, Transfusions, and Cost.

INTRODUCTION: Orthotopic liver transplantation (OLT) can be associated with significant bleeding requiring multiple blood product transfusions. Rotational thromboelastometry (ROTEM) is a point-of-care device that has been used to monitor coagulation during OLT. Whether it reduces blood loss/transfusions during OLT remains controversial. MATERIALS AND METHODS: We aim to compare ROTEM with conventional coagulation tests (aPTT, PT, INR, platelet count, fibrinogen) to guide transfusion of platelets, cryoprecipitate, and fresh frozen plasma (FFP) during OLT over 3 years. Thirty-four patients who had transfusions guided by ROTEM were compared to 34 controls who received transfusions guided by conventional coagulation tests (CCT). Intraoperative blood loss, type/ amount of blood products transfused, and direct costs were compared between the two groups. RESULTS: The ROTEM group had significantly less intra-operative blood loss (2.0 vs. 3.0 L, p = 0.04) and fresh frozen plasma (FFP) transfusion (4 units vs. 6.5 units, p = 0.015) compared to the CCT group (2.0L vs. 3.0L, p = 0.04). However, total number of patients transfused cryoprecipitate was increased in ROTEM (n = 25;73%) as compared to CCT (n = 19; 56%), p = 0.033. The direct cost of blood products plus testing was reduced in the ROTEM group ($113,142.89 vs. $127,814.77). CONCLUSION: In conclusion implementation of a ROTEM-guided transfusion algorithm resulted in a reduction in intra-operative blood loss, FFP transfusion and a decrease in direct cost during OLT. ROTEM is a useful and safe point of care device in OLT setting.

Magnitude of Potentially Inappropriate Thrombophilia Testing in the Inpatient Hospital Setting.

Laboratory costs of thrombophilia testing exceed an estimated $650 million (in US dollars) annually. Quantifying the prevalence and financial impact of potentially inappropriate testing in the inpatient hospital setting represents an integral component of the effort to reduce healthcare expenditures. We conducted a retrospective analysis of our electronic medical record to evaluate 2 years' worth of inpatient thrombophilia testing measured against preformulated appropriateness criteria. Cost data were obtained from the Centers for Medicare and Medicaid Services 2016 Clinical Laboratory Fee Schedule. Of the 1817 orders analyzed, 777 (42.7%) were potentially inappropriate, with an associated cost of $40,422. The tests most frequently inappropriately ordered were Factor V Leiden, prothrombin gene mutation, protein C and S activity levels, antithrombin activity levels, and the lupus anticoagulant. Potentially inappropriate thrombophilia testing is common and costly. These data demonstrate a need for institution-wide changes in order to reduce unnecessary expenditures and improve patient care.

Diagnostic Testing Approaches for Activated Protein C Resistance and Factor V Leiden: A Comparison of Institutional and National Provider Practices.

OBJECTIVES: To analyze the economic impact of testing for activated protein C resistance (APC-R) due to factor V Leiden (FVL) mutation with APC-R with reflexive FVL genotyping (algorithmic approach) or genotyping alone. METHODS: OptumLabs Data Warehouse (OLDW) data were used to assess testing approaches. Insurance claims for APC-R and FVL in 2013 were compared with the Mayo Clinic database. Centers for Medicare & Medicaid Services diagnostic fee schedules were used to assign costs. RESULTS: Of 19.3 million OLDW-covered individuals, 74,242 (0.385%) received 75,608 tests: APC-R, 2,265 (2.9%); FVL genotyping, 70,619 (90.1%); and both APC-R and FVL, 2,724 (7.0%). In total, 1,317 tests were performed at Mayo Clinic: APC-R with reflex FVL (1,256; 95.4%) and FVL alone (61; 4.6%). Costs per evaluated individual and per total population (person/year) in OLDW and algorithmic approach were $83.77 vs $36.38 and $0.32 vs $0.14, respectively. CONCLUSIONS: The cost-optimized algorithmic approach reduces health care costs.

Thromboelastometry versus standard coagulation tests versus restrictive protocol to guide blood transfusion prior to central venous catheterization in cirrhosis: study protocol for a randomized controlled trial.

BACKGROUND: Liver failure patients have traditionally been empirically transfused prior to invasive procedures. Blood transfusion is associated with immunologic and nonimmunologic reactions, increased risk of adverse outcomes and high costs. Scientific evidence supporting empirical transfusion is lacking, and the best approach for blood transfusion prior to invasive procedures in cirrhotic patients has not been established so far. The aim of this study is to compare three transfusion strategies (routine coagulation test-guided - ordinary or restrictive, or thromboelastometry-guided) prior to central venous catheterization in critically ill patients with cirrhosis. METHODS/DESIGN: Design and setting: a double-blinded, parallel-group, single-center, randomized controlled clinical trial in a tertiary private hospital in São Paulo, Brazil. INCLUSION CRITERIA: adults (aged 18 years or older) admitted to the intensive care unit with cirrhosis and an indication for central venous line insertion. Patients will be randomly assigned to three groups for blood transfusion strategy prior to central venous catheterization: standard coagulation tests-based, thromboelastometry-based, or restrictive. The primary efficacy endpoint will be the proportion of patients transfused with any blood product prior to central venous catheterization. The primary safety endpoint will be the incidence of major bleeding. Secondary endpoints will be the proportion of transfusion of fresh frozen plasma, platelets and cryoprecipitate; infused volume of blood products; hemoglobin and hematocrit before and after the procedure; intensive care unit and hospital length of stay; 28-day and hospital mortality; incidence of minor bleeding; transfusion-related adverse reactions; and cost analysis. DISCUSSION: This study will evaluate three strategies to guide blood transfusion prior to central venous line placement in severely ill patients with cirrhosis. We hypothesized that thromboelastometry-based and/or restrictive protocols are safe and would significantly reduce transfusion of blood products in this population, leading to a reduction in costs and transfusion-related adverse reactions. In this manner, this trial will add evidence in favor of reducing empirical transfusion in severely ill patients with coagulopathy. TRIAL REGISTRATION: ClinicalTrials.gov, identifier: NCT02311985 . Retrospectively registered on 3 December 2014.

Using the Electronic Medical Record to Reduce Unnecessary Ordering of Coagulation Studies for Patients with Chest Pain.

INTRODUCTION: Our goal was to reduce ordering of coagulation studies in the emergency department (ED) that have no added value for patients presenting with chest pain. We hypothesized this could be achieved via implementation of a stopgap measure in the electronic medical record (EMR). METHODS: We used a pre and post quasi-experimental study design to evaluate the impact of an EMR-based intervention on coagulation study ordering for patients with chest pain. A simple interactive prompt was incorporated into the EMR of our ED that required clinicians to indicate whether patients were on anticoagulation therapy prior to completion of orders for coagulation studies. Coagulation order frequency was measured via detailed review of randomly sampled encounters during two-month periods before and after intervention. We classified existing orders as clinically indicated or non-value added. Order frequencies were calculated as percentages, and we assessed differences between groups by chi-square analysis. RESULTS: Pre-intervention, 73.8% (76/103) of patients with chest pain had coagulation studies ordered, of which 67.1% (51/76) were non-value added. Post-intervention, 38.5% (40/104) of patients with chest pain had coagulation studies ordered, of which 60% (24/40) were non-value added. There was an absolute reduction of 35.3% (95% confidence interval [CI]: 22.7%, 48.0%) in the total ordering of coagulation studies and 26.4% (95% CI: 13.8%, 39.0%) in non-value added order placement. CONCLUSION: Simple EMR-based interactive prompts can serve as effective deterrents to indiscriminate ordering of diagnostic studies.

Targeted Bleeding Management Reduces the Requirements for Blood Component Therapy in Lung Transplant Recipients.

OBJECTIVE: Lung transplantation is associated with high rates of bleeding and frequent blood transfusion. The authors aimed to determine if point-of-care coagulation testing (POCCT) reduced transfusion requirements. DESIGN, SETTINGS, AND PARTICIPANTS: A before-and-after cohort analysis conducted at a single tertiary referral center. Ninety-three sequential adult patients between January 2010 and January 2014 undergoing isolated lung transplant without preoperative extracorporeal support were analyzed. INTERVENTION: ROTEM and multi-plate POCCT were introduced on July 1, 2012, with an associated algorithm based on the results. MEASUREMENTS AND MAIN RESULTS: Statistically significant decreases in the proportion of patients receiving PRBCs (87% v 65%; p = 0.015), FFP (72% v 30%; p<0.0001) and platelets (70% v 37%; p = 0.002) were found after the intervention. There were small decreases in median chest tube blood loss at 2 hours (300 mLs v 215 mLs; p = 0.03) and 4 hours (440 mLs v 350 mLs; p = 0.050) but not at 12 hours postoperatively. There were no changes in reoperation for bleeding (9% v 4%; p = 0.158) or in-hospital mortality (6% v 2%; p = 0.617). The cost of blood products administered decreased from a median of $3,935.00 to $991.00 (p<0.001). CONCLUSIONS: Use of POCCT in lung-transplant surgery is associated with significant reductions in blood product use and cost. There were no detectable changes in outcome aside from a small decrease in early postoperative bleeding.

Cost-Effectiveness of POC Coagulation Testing Using Multiple Electrode Aggregometry.

BACKGROUND: The economic effects of Point-of-Care (POC) coagulation testing including Multiple Electrode Aggregometry (MEA) with the Multiplate device have not been examined. METHODS: A health economic model with associated clinical endpoints was developed to calculate the effectiveness and estimated costs of coagulation analyses based on standard laboratory testing (SLT) or POC testing offering the possibility to assess platelet dysfunction using aggregometric measures. Cost estimates included pre- and perioperative costs of hemotherapy, intra- and post-operative coagulation testing costs, and hospitalization costs, including the costs of transfusion-related complications. RESULTS: Our model calculation using a simulated true-to-life cohort of 10,000 cardiac surgery patients assigned to each testing alternative demonstrated that there were 950 fewer patients in the POC branch who required any transfusion of red blood cells. The subsequent numbers of massive transfusions and patients with transfusion-related complications were reduced with the POC testing by 284 and 126, respectively. The average expected total cost in the POC branch was 288 Euro lower for every treated patient than that in the SLT branch. CONCLUSIONS: Incorporating aggregometric analyses using MEA into hemotherapy algorithms improved medical outcomes in cardiac surgery patients in the presented health economic model. There was an overall better economic outcome associated with POC testing compared with SLT testing despite the higher costs of testing.

Analysis of Thrombophilia Test Ordering Practices at an Academic Center: A Proposal for Appropriate Testing to Reduce Harm and Cost.

Ideally, thrombophilia testing should be tailored to the type of thrombotic event without the influence of anticoagulation therapy or acute phase effects which can give false positive results that may result in long term anticoagulation. However, thrombophilia testing is often performed routinely in unselected patients. We analyzed all consecutive thrombophilia testing orders during the months of October and November 2009 at an academic teaching institution. Information was extracted from electronic medical records for the following: indication, timing, comprehensiveness of tests, anticoagulation therapy at the time of testing, and confirmatory repeat testing, if any. Based on the findings of this analysis, we established local guidelines in May 2013 for appropriate thrombophilia testing, primarily to prevent testing during the acute thrombotic event or while the patient is on anticoagulation. We then evaluated ordering practices 22 months after guideline implementation. One hundred seventy-three patients were included in the study. Only 34% (58/173) had appropriate indications (unprovoked venous or arterial thrombosis or pregnancy losses). 51% (61/119) with an index clinical event were tested within one week of the event. Although 46% (79/173) were found to have abnormal results, only 46% of these had the abnormal tests repeated for confirmation with 54% potentially carrying a wrong diagnosis with long term anticoagulation. Twenty-two months after guideline implementation, there was an 84% reduction in ordered tests. Thus, this study revealed that a significant proportion of thrombophilia testing was inappropriately performed. We implemented local guidelines for thrombophilia testing for clinicians, resulting in a reduction in healthcare costs and improved patient care.

A computer-based model to assess costs associated with the use of factor VIII and factor IX one-stage and chromogenic activity assays.

BACKGROUND: Measurement of coagulation factor factor VIII (FVIII) and factor IX (FIX) activity can be associated with a high level of variability using one-stage assays based on activated partial thromboplastin time (APTT). Chromogenic assays show less variability, but are less commonly used in clinical laboratories. In addition, one-stage assay accuracy using certain reagent and instrument combinations is compromised by some modified recombinant factor concentrates. Reluctance among some in the hematology laboratory community to adopt the use of chromogenic assays may be partly attributable to lack of familiarity and perceived higher associated costs. OBJECTIVES: To identify and characterize key cost parameters associated with one-stage APTT and chromogenic assays for FVIII and FIX activity using a computer-based cost analysis model. METHODS: A cost model for FVIII and FIX chromogenic assays relative to APTT assays was generated using assumptions derived from interviews with hematologists and laboratory scientists, common clinical laboratory practise, manufacturer list prices and assay kit configurations. RESULTS: Key factors that contribute to costs are factor-deficient plasma and kit reagents for one-stage and chromogenic assays, respectively. The stability of chromogenic assay kit reagents also limits the cost efficiency compared with APTT testing. Costs for chromogenic assays might be reduced by 50-75% using batch testing, aliquoting and freezing of kit reagents. CONCLUSIONS: Both batch testing and aliquoting of chromogenic kit reagents might improve cost efficiency for FVIII and FIX chromogenic assays, but would require validation. Laboratory validation and regulatory approval as well as education and training in the use of chromogenic assays might facilitate wider adoption by clinical laboratories.