Archives

  • 2018-07
  • 2019-04
  • 2019-05
  • 2019-06
  • 2019-07
  • 2019-08
  • 2019-09
  • 2019-10
  • 2019-11
  • 2019-12
  • 2020-01
  • 2020-02
  • 2020-03
  • 2020-04
  • 2020-05
  • 2020-06
  • 2020-07
  • 2020-08
  • 2020-09
  • 2020-10
  • 2020-11
  • 2020-12
  • 2021-01
  • 2021-02
  • 2021-03
  • 2021-04
  • 2021-05
  • 2021-06
  • 2021-07
  • 2021-08
  • 2021-09
  • 2021-10
  • 2021-11
  • 2021-12
  • 2022-01
  • 2022-02
  • 2022-03
  • 2022-04
  • 2022-05
  • 2022-06
  • 2022-07
  • 2022-08
  • 2022-09
  • 2022-10
  • 2022-11
  • 2022-12
  • 2023-01
  • 2023-02
  • 2023-03
  • 2023-04
  • 2023-05
  • 2023-06
  • 2023-08
  • 2023-09
  • 2023-10
  • 2023-11
  • 2023-12
  • 2024-01
  • 2024-02
  • 2024-03
  • 2024-04

    • NVP-BHG712 A previous study from our institution showed mode

    2022-06-21

    A previous study from our institution showed moderate correlation between the APTT and Anti-FXa assays, prompting an institution-wide change to an Anti-FXa based monitoring of unfractionated heparin. The current study is a descriptive analysis to evaluate the clinical outcomes in this pediatric cohort treated with unfractionated heparin and monitored using an Anti-FXa nomogram, specifically looking at its safety and efficacy. In addition, given that we simultaneously obtained APTT values with the Anti-FXa assay, we sought to investigate the correlation between the 2 assays. Methods
    Results Over the course of 20 months, 173 patients received therapeutic doses of unfractionated heparin at Nationwide Children's Hospital (Figure 1). In total, 95 patients were included in the final analysis of this study; there were 1098 pairs of APTT and Anti-FXa measurements performed. The majority of the patients in our study cohort were male (n = 60; 63%). The median age was 8 years (range 0.1-20 years) and one-third of the patients (n = 25; 26%) were infants <1 year of age (range 4 days to 10 months of age). The median weight at the time of anticoagulation NVP-BHG712 was 28.6 kg (range 1.65-131.3 kg). The most common indication for unfractionated heparin use was acute treatment/prophylaxis of thromboembolism (n = 77; 81%) and primary thromboprophylaxis for children with complex congenital cardiac disease (n = 18; 19%). For children with venous thrombosis, indwelling central venous catheter was the single most common risk factor present (Table II). During the study period, the median duration of unfractionated heparin therapy for each patient was 3.5 days (range 1-45 days), and during this time, each patient had a median of 8 pairs of APTT and Anti-FXa assays perfumed (range 1-46). A median unfractionated heparin dose of 22 units/kg/h was required to reach therapeutic Anti-FXa levels, and this was significantly greater in infants <1 year of age as compared with older children (33.9 vs 20 units/kg/h; P <.001). Each patient had an average of 2.5 (median: 2; range 0.25-8) Anti-FXa measurements performed per day and a mean 1.1 (median: 1; range 0-4.5) infusion rate changes made per day of therapy to maintain plasma heparin levels within the goal range of 0.35-0.7 units/mL. Time to achieve sustained therapeutic Anti-FXa levels was a median of 10 hours (range 2-96 hours), and this duration was significantly shorter in patients who received a heparin bolus at the start of anticoagulation therapy as compared with the patients who did not receive a bolus (5 hours vs 12 hours; P = .03). A bolus dose was not administered in 47 patients. Indications for not administering the bolus included recent surgery (n = 16), ongoing hemorrhage (n = 13), transition from prophylactic to therapeutic dosing (n = 7), coagulopathy (n = 4), stroke (n = 3), prematurity (n = 1), and unknown (n = 3). Overall, 73 patients (77%) achieved sustained therapeutic Anti-FXa levels within 24 hours of starting anticoagulation with unfractionated heparin, and 91 patients (96%) were therapeutic within 48 hours.
    Discussion Unfractionated heparin remains the cornerstone of anticoagulant therapy in critically ill children for the treatment and prevention of thromboembolism. The goal of therapeutic drug monitoring for unfractionated heparin is to maximize protection from thrombus progression while minimizing the risk of bleeding.28, 29 Broad availability, automation, and quick turnaround time has popularized APTT to monitor heparin dose within a narrow therapeutic range.5, 8, 22, 30 However, APTT testing is influenced by preanalytical, analytical, and biological variables that do not reflect in vitro heparin activity.6, 7, 8, 9, 10, 11, 12 Hence, when APTT is used to monitor unfractionated heparin therapy, patients may be exposed to precariously low or high heparin levels, decreasing the therapeutic efficacy of unfractionated heparin, or increasing the risk of bleeding, respectively. Anti-FXa reflects the anticoagulant activity of unfractionated heparin by measuring the ability of heparin–antithrombin complex to inhibit activated factor X. Anti-FXa testing is more expensive and less widely available but demonstrates less susceptibility to interference by biological variables, making it a more direct measure of the anticoagulant effect of unfractionated heparin than APTT.2, 18, 19