Table 2.
Distribution of Anti–Factor Xa Values at First, Second, and Third Measurements after Initiation of UFH Infusion
|
Subtherapeutic Anti-Xa (≤ 0.30 IU/mL)
|
Therapeutic Anti-Xa (0.31–0.70 IU/mL)
|
Supratherapeutic Anti-Xa (≥ 0.71 IU/mL)
|
||||
|---|---|---|---|---|---|---|
| Measurement* | No. (%) | p value | No. (%) | p value | No. (%) | p value |
| First (after 6 h) | < 0.001 | 0.007 | 0.38 | |||
| UFH-D5W (n = 100) | 17 (17) | 60 (60) | 23 (23) | |||
| UFH-NS (n = 100) | 43 (43) | 40 (40) | 17 (17) | |||
|
| ||||||
| Second | < 0.001 | 0.001 | 0.038† | |||
| UFH-D5W (n = 100) | 23 (23) | 71 (71) | 6 (6) | |||
| UFH-NS (n = 100) | 61 (61) | 39 (39) | 0 (0) | |||
|
| ||||||
| Third | 0.004 | 0.01 | 0.72 | |||
| UFH-D5W (n = 91) | 25 (27) | 61 (67) | 5 (5) | |||
| UFH-NS (n = 88) | 43 (49) | 42 (48) | 3 (3) | |||
UFH-D5W = heparin sodium 100 units/mL in dextrose 5% in water, UFH-NS = heparin sodium 100 units/mL in 0.9% sodium chloride.
*
After mandatory measurement of anti–factor Xa at 6 h after initiation of infusion, the timing of further measurements of anti-Xa for each patient was dependent on the result of the previous measurement, according to the nomogram.
†
Yates correction.