A comparison of coagulation study results between heparinized peripherally inserted central catheters and...

The purpose of this study was to test an evidence-based procedure of drawing blood samples for coagulation testing from heparinized peripherally inserted central catheter (PICC) by comparing results with blood drawn from venipuncture (VP).

A prospective, quasi-experimental design using purposive sampling was used.

The setting was a 230-bed community hospital located in the Southwest. The hospital is part of a 15-hospital system.

: The sample was composed of 30 hospitalized patients with heparinized PICCs.

Informed consent was obtained. Using aseptic technique, samples of blood were drawn via VP and from the PICC using the evidence-based procedure. Data were analyzed using Pearson product moment correlations and Bland-Altman analysis.

For 5 coagulation tests studied, correlations between PICC values and VP values ranged from 0.990 to 0.998, indicating almost perfect correlations. In Bland-Altman analyses, mean biases and SDs were small to moderate for prothrombin time, 0.13 seconds (-0.55 to 0.81 seconds) (P = 0.0484); international normalized ratio, 0.010 (-0.050 to 0.070) (P = 0.085); partial thromboplastin time, 2.16 seconds (-5.10 to 9.43 seconds) (P = 0.0033); and fibrinogen, -18.2 mg (-70.4 to 34.1 mg) (P = 0.0033) and 0.52 (-0.73 to 1.77) seconds (P = 0.0003). Correlations of absolute difference versus average ranged from 0.18 to 0.49. Only the paired international normalized ratio samples had P values suggesting nonagreement.

Drawing blood samples from heparinized PICCs for coagulation tests using the evidence-based procedure developed for this study resulted in accurate coagulation test results in 4 of the 5 tests: prothrombin time, partial thromboplastin time, and fibrinogen in seconds and in milligrams.