Neurología (English Edition) (Apr 2020)
Reliability of point-of-care coagulometer measurements in patients with acute ischaemic stroke receiving intravenous fibrinolysis
Abstract
Background: Speed of administration conditions the effectiveness of intravenous fibrinolysis in treating acute ischaemic stroke. To reduce the risk of haemorrhagic complications, the intervention is contraindicated in certain cases, such as where the International Normalised Ratio (INR) is ≥1.7. This study aimed to determine the reliability of point-of-care INR readings (POC-INR) taken using the CoaguChek® XS portable coagulometer compared to laboratory results (L-INR). Methods: We conducted a retrospective observational study of consecutive patients admitted to our centre with acute ischaemic stroke and who were treated with intravenous fibrinolysis, over a period of 4 years. Patients’ INR was measured with a portable coagulometer and in the laboratory. Results were compared using the paired-sample t test; using L-INR results as a reference value, ROC analysis was performed to determine POC-INR with greater predictive value. Results: The study included 210 patients with a mean age of 74.3 ± 11.5 years old; 18 (8.6%) were taking vitamin K antagonist oral anticoagulants (OAC). There were no significant differences between the 2 INR measurements in the population as a whole (POC-INR–L-INR difference: 0.001 ± 0.085; P = .82). In subgroup analysis, the results coincided for patients taking OACs (0.001 ± 0.081; P = .42) and those with L-INR ≤ 1.2 (0.008 ± 0.081; P = .16). For L-INR > 1.2, however, the portable coagulometer underestimated INR (0.058 ± 0.095; P = .01). Through ROC analysis, POC-INR 1,2, CPINR infraestimó la INR (diferencia LINR-CPINR 0,058 ± 0,095; p = 0,01). Mediante análisis ROC una CPINR < 1,6 fue el punto de corte más sensible y específico para seleccionar pacientes tratables con fibrinólisis intravenosa (LINR < 1,7). Conclusiones: El CP en el código ictus tiene una buena concordancia con el laboratorio. Este estudio indica que en nuestro centro una CPINR < 1,6 es el mejor umbral para predecir una LINR< 1,7. La validación de la CPINR en cada centro es recomendable para su uso protocolizado.