Validation of a Point-of-Care Analyzer for Determining Anticoagulation Status During Air Transport

We evaluated a point-of-care prothrombin time (PT)/international normalized ratio (INR) cartridge-based analyzer for its feasibility, accuracy, and value in critical care air transport.

In this prospective study, blood samples from 10 randomly selected adult patients were tested with the cartridge during transport to determine feasibility. The cartridge results were compared with the laboratory results for the same samples. Similarly, blood samples from an additional 20 randomly selected adult patients were tested to determine test accuracy. A chart review identified 110 adult patients with PT/INR cartridge results to determine the clinical value of those results.

Data from the first group of 10 patients showed that vibration did not affect use of the cartridge. The average bias between the 2 testing methods was 0.0 INR units. A comparison of the PT/INR cartridge results and the laboratory results from the group of 20 patients showed that 73% of the cartridge values were within 0.2 of the laboratory values, 83% were within 0.4, and 93% were within 0.6. Of the 110 patients whose charts showed PT/INR cartridge results, 23% received blood products (45 trauma patients and 65 medical patients).

The PT/INR cartridge withstands the rigors of rotor wing transport and provides accurate, valuable results for making clinical decisions.