Point-of-care monitoring of anticoagulant therapy in paediatric patients

EMPoWARed: Edmonton pediatric warfarin self-management study

BACKGROUND

Patient self-management (PSM) in adults is safer and more cost effective than conventional management. Warfarin is a narrow therapeutic index drug with individual patient response to changes and frequently a long-term therapy. Children and their families are proposed to be able to effectively manage their child's warfarin therapy. Increased health related quality of life is highly associated with effective therapy in patients with chronic conditions.

OBJECTIVES

The aim of this study is to evaluate the safety and efficacy of PSM over time including HRQOL and variables that may influence PFU success at PSM.

PATIENTS/METHODS

Children and their family units (PFUs) current performing patient self-testing/monitoring for ≥ 3 months were enrolled in this cohort study. PFUs participated in comprehensive education on warfarin testing and management followed by an apprenticeship. Socio-demographic, clinical, and laboratory data were collected to evaluate safety and efficacy and health related quality of life. Outcomes were compared between the first 6 months on PSM (phase 1) and the last 6 months data collected on PSM (phase 2).

RESULTS

Forty-two patients performed PSM for a median of 2.7 years (range: 1.1-6.2 years). Time in therapeutic range was 90% and 92.9% (p=0.30) in phases 1 and 2 respectively. All measures were strongly associated with improved heath related quality of life. PFUs socio-demographic status did not influence success at PSM. All PFUs maintained warfarin knowledge and INR testing competency. Warfarin dosing decision errors median 0 (range: 0-5, p=0.73) and a median 0 (range 0-4, p=0.55) per patient in phases 1 and 2 respectively. There were no adverse hemorrhagic or thrombotic events.

CONCLUSIONS

Empowering PFUs to self-manage warfarin results in increased knowledge and understanding of their health condition, improved commitment to their health care and adherence to medication regimens and is demonstrated to be sustainable over time.

[Evaluation of an educational program for oral anticoagulation in children with the INR home-monitoring CoaguChek XS(®)]

OBJECTIVE

To assesses the results of our education program relative to anticoagulation therapy and self-monitoring of INR.

MATERIALS AND METHODS

All children treated with oral anticoagulation therapy and followed using INR self-monitoring in Tours and Nantes, France, were included. A questionnaire on the treatment and its management was sent to the patients and their family. We analyzed the quality of anticoagulation using the proportion of INR within the target range.

RESULTS

Thirty-three children were included, with a mean age of 10.9years. Thirty-one questionnaires could be analyzed. Insufficient knowledge on the treatment objective and risks, the INR target range, and the interpretation of the INR was observed. We found 65.8% of INRs within the target range. The proportion of INRs within the target range was better with the INR self-testing than with the laboratory test (69.7% vs. 49.1%, P=0.003). There was no major complication observed during the study period. A moderate correlation (K=0.57) was noted between the INRs measured with the point-of-care monitor and the laboratory test on the same day.

CONCLUSION

However, home-monitoring of oral anticoagulation therapy increases the quality of anticoagulation. Both education and the training program need improvement in order to provide patients and their families with better knowledge on anticoagulation therapy.

Point-of-care INR measurement in children requiring warfarin: what has been evaluated and future directions

Many children are surviving primary illnesses and now require thromboprophylaxis as a result of advances in management. Vitamin K antagonists are commonly prescribed to prevent or treat thrombosis. These agents are far more challenging to effectively manage in children. As a result of these challenges, frequent blood monitoring to measure international normalized ratio (INR) values is required. Point-of-care (POC) INR monitors use a capillary blood sample that has been expressed as a solution to improve effective management of vitamin K antagonist therapy. POC INR meters have been demonstrated to be accurate and precise in measuring INRs. Implementation of a standardized education program prior to patient use of POC meters results in differences between measured laboratory INRs and POC INR comparisons that meet criteria for clinical relevance. This indicates that POC INR meters are safe and effective for use in children.

Nadroparin therapy in pediatric patients with venous thromboembolic disease

Low-molecular-weight heparins are increasingly used for treatment of pediatric venous thromboembolic disease (VTE). Pediatric data about therapeutic doses of nadroparin are not available. To evaluate pharmacodynamics and safety of therapeutic doses of nadroparin, consecutive patients (age 0 to 18 y) with objectively diagnosed VTE and treated with nadroparin were included in this single center study over a 12-year period. All patients started with 85.5 IU/kg of nadroparin twice daily. The target therapeutic range (TTR) was set at 0.5 to 1.0 anti-Xa IU/mL 4 hours postdose. Safety end points were major bleeding and therapy-related death. A total of 84 patients were enrolled, of whom 8 patients did not undergo measurement of anti-Xa levels. Fifty-four (71%) of 76 patients achieved TTR. The maintenance dose (mean+/-SE) was 448+/-42 IU/kg/d in neonates (<2 mo, n=6), 253+/-22 IU/kg/d in infants (2 mo to 1 y, n=10), 214+/-8 IU/kg/d in children (2 to 11 y, n=13), and 183+/-5 IU/kg/d in adolescents (12 to 18 y, n=25). Neonates required significantly more dose adjustments and time to achieve TTR than adolescents. No major bleeding or therapy-related death occurred. In summary, an age-dependent response to nadroparin exists in pediatric patients. Nadroparin therapy seems to be safe for treatment of pediatric VTE.