Evaluation of a Multimodal Heparin Laboratory Monitoring Protocol in Adult Extracorporeal Membrane Oxygenation Patients.

BACKGROUND: Anticoagulation monitoring practices vary during extracorporeal membrane oxygenation (ECMO). The Extracorporeal Life Support Organization describes that a multimodal approach is needed to overcome assay limitations and minimize complications. OBJECTIVE: Compare activated clotting time (ACT) versus multimodal approach (activated partial thromboplastin time (aPTT)/anti-factor Xa) for unfractionated heparin (UFH) monitoring in adult ECMO patients. METHODS: We conducted a single-center retrospective pre- (ACT) versus post-implementation (multimodal approach) study. The incidence of major bleeding and thrombosis, blood product and antithrombin III (ATIII) administration, and UFH infusion rates were compared. RESULTS: Incidence of major bleeding (69.2% versus 62.2%, p = 0.345) and thrombosis (23% versus 14.9%, p = 0.369) was similar between groups. Median number of ATIII doses was reduced in the multimodal group (1.0 [IQR 0.0-2.0] versus 0.0 [0.0 -1.0], p = 0.007). The median UFH infusion rate was higher in the ACT group, but not significant (16.9 [IQR 9.6-22.4] versus 13 [IQR 9.6-15.4] units/kg/hr, p = 0.063). Fewer UFH infusion rate changes occurred prior to steady state in the multimodal group (0.9 [IQR 0.3 -1.7] versus 0.1 [IQR 0.0-0.2], p < 0.001). CONCLUSION: The incidence of major bleeding and thrombosis was similar between groups. Our multimodal monitoring protocol standardized UFH infusion administration and reduced ATIII administration.

Difficulties Detecting Clinically Relevant Factor Xa Inhibitor Levels Prior to Reversal With Andexanet Alfa for Intracranial Hemorrhage.

Coagulation factor Xa (recombinant), inactivated-zhzo (andexanet alfa) is approved for reversal of life-threatening bleeding with rivaroxaban and apixaban use. Clinical decision-making to initiate reversal is reliant on dose taken and timing of last dose. In practice, timing of last dose may be unknown, and the turnaround time for drug-specific anti-factor Xa levels at some institutions may be prolonged, leaving clinicians balancing a difficult decision with limited tools. This report includes a series of 3 patients who presented to our institution with an intracranial hemorrhage and received andexanet alfa for apixaban reversal. These cases highlight the challenges clinicians are facing when using andexanet alfa for emergent rivaroxaban or apixaban reversal when the timing of last dose is unknown, or patients fall outside of the recommended timeframe for use and clinically relevant drug levels are still suspected. Based on our experiences, we encourage other institutions to evaluate their abilities to rapidly and accurately detect the presence of clinically relevant rivaroxaban and apixaban levels when utilizing andexanet alfa.

Major Bleeding and Thrombosis Events in COVID-19 Versus Influenza Patients Requiring Extracorporeal Membrane Oxygenation.

Initial reports described a hypercoagulable state and an increased risk of thrombosis in patients who tested positive for SARS-CoV-2. Infected patients with severe acute respiratory distress syndrome in the setting of coronavirus disease 2019 (COVID-19) may require extracorporeal membrane oxygenation (ECMO), leading to coagulopathies and further increasing the risk for bleeding and thrombosis. We conducted a single-center retrospective cohort study to compare the incidence of major bleeding and thrombosis in COVID-19 versus influenza-positive patients requiring ECMO. There was no difference in the incidence of major bleeding (67.7% vs. 85.7%, p = 0.287) or major thrombosis (9.7% vs. 21.4%, p = 0.356) between COVID-19 and influenza patients, respectively. COVID-19 patients experienced significantly fewer major bleeding events per ECMO days compared with influenza (0.1 [interquartile range 0-0.2] vs. 0.2 [interquartile range 0.1-0.5], p = 0.026). Influenza patients may be at higher risk for developing coagulopathies that contribute to bleeding. Larger evaluations are needed to confirm these results and further assess bleeding and thrombosis risk in these populations.

Accuracy of a modified 4Ts score in predicting heparin-induced thrombocytopenia in critically ill patients: A pilot study.

PURPOSE: Thrombocytopenia is common among critically ill patients and heparin-induced thrombocytopenia (HIT) is often on the differential. Professional guidelines recommend calculating a pre-test probability score before performing HIT testing. The 4Ts score is widely utilized but accuracy has been questioned in critically ill patients. The HIT Expert Probability (HEP) score is available, but complexity limits use. Our objective was to compare a modified intensive care unit (ICU)-4Ts score to available scoring tools. MATERIALS AND METHODS: This was a single-center retrospective pilot study. Adult ICU patients that were tested for HIT and had a documented 4Ts score were included. A blinded investigator retrospectively calculated the HEP and ICU-4Ts score. Receiver operating characteristics (ROC) area under the curve (AUC), sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were compared. RESULTS: In 194 included patients, ROC AUC was significantly higher for the ICU-4Ts compared to the 4Ts score (0.80 versus 0.66, respectively; p = 0.044). The ICU-4Ts score had the highest specificity, PPV, and NPV. The sensitivity was similar between the HEP and ICU-4Ts score. CONCLUSIONS: The ICU-4Ts score better predicted the diagnosis of HIT compared to the 4Ts score. Prospective validation studies are needed to confirm these results.

Accuracy and safety of medication histories obtained at the time of intensive care unit admission of delirious or mechanically ventilated patients.

PURPOSE: Obtaining an accurate medication history from patients on hospital admission is a priority in pharmacy practice. Timely and accurate histories are imperative as they may help determine the etiology of illness and prevent medication errors. We conducted a quality improvement project to assess the accuracy of alternate-source medication histories obtained for critically ill patients who were delirious or mechanically ventilated at the time of intensive care unit admission. METHODS: Included patients were 18 years of age or older, admitted to the medical intensive care unit from August 2017 through January 2018, and had a medication history obtained from a family member or outpatient pharmacy due to active delirium or mechanical ventilation. Patients were directly interviewed after resolution of delirium or extubation. Discrepancies between the initial and follow-up histories were documented and categorized using the National Coordinating Council for Medication Error Reporting and Prevention (NCC MERP) Index for Categorizing Medication Errors. RESULTS: Forty patients were included. One hundred four discrepancies were documented, with a median of 2 discrepancies per patient. The most common types of discrepancies were addition (51.9%), followed by omission (24.0%). NCC MERP index category A (51%) was the most common error classification identified. CONCLUSION: Discrepancies between initial and follow-up medication histories occurred at a frequent rate in delirious or mechanically ventilated patients; however, these discrepancies tended to be of low risk severity.

Impact of a multidisciplinary workflow on safety and management of patients with heparin-induced thrombocytopenia.

PURPOSE: Heparin-induced thrombocytopenia (HIT) is a serious complication of heparin administration. Management strategies are complex and include discontinuing heparin products, initiating alternative anticoagulants, interpreting laboratory test results, documenting heparin allergies, and providing patient education. Medication error reports and a retrospective review conducted at an academic medical center revealed an opportunity for a quality improvement initiative and led to the creation of a multidisciplinary workflow for the management of HIT. In a pre-post study, the impact of the multidisciplinary workflow on the safety and management of HIT was evaluated. METHODS: The preimplementation group consisted of adult patients tested for suspected HIT from April 4, 2014, through May 31, 2016; the postimplementation group consisted of adult patients tested from November 1, 2016, through October 31, 2018. The primary outcome was the incidence of heparin product administration while HIT testing was ongoing. The secondary outcome was the rate of appropriate heparin allergy documentation. RESULTS: The incidence of heparin product administration while HIT testing results were pending was significantly reduced, from 54.2% to 20.0% (P < 0.001), after workflow implementation. The rate of appropriate heparin allergy documentation significantly increased, from 95.0% to 100% (P < 0.001). CONCLUSION: Implementation of a multidisciplinary workflow for the management of HIT significantly reduced the incidence of heparin administration while testing was ongoing and improved the rate of appropriate heparin allergy documentation.

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.

Evaluation of 4Ts score inter-rater agreement in patients undergoing evaluation for heparin-induced thrombocytopenia.

The American Society of Hematology and American College of Chest Physicians heparin-induced thrombocytopenia guidelines recommend calculation of a pretest probability score prior to performing laboratory testing, and the 4Ts score is commonly used. Inter-rater agreement of the 4Ts score has been evaluated, but limited data are available regarding the reliability of the 4Ts score when performed by nonexpert clinicians. The purpose of this study was to Compare 4Ts scores calculated by medical teams to an expert. A single-center observational study was conducted in patients evaluated for heparin-induced thrombocytopenia over 24 months. The primary outcome was difference in mean 4Ts score calculated by the medical team compared with an expert. Secondary outcomes included inter-rater agreement in risk category assignment and the negative predictive value (NPV) of the 4Ts score. The mean total 4Ts score was significantly higher when calculated by the medical team compared with expert (4.16 ±â€Š1.41 versus 3.42 ±â€Š1.53; P < 0.001). There was slight agreement in risk category assignment (Cohen κ coefficient = 0.164; P = 0.005). The NPV of the 4Ts score was 0.949 (95% confidence interval 0.891-1.000) when calculated by the medical team and 0.927 (95% confidence interval 0.869-0.984) when calculated by expert. Total 4Ts scores calculated by the medical team were significantly higher with only slight inter-rater agreement compared with expert. The NPV of the 4Ts score when calculated by nonexperts may be lower than previously reported. The recommendation to forgo laboratory testing for low 4Ts score patients may need to be revisited.