TABLE 4.

Trial Clinical Outcomes by Age of Cold Stored Platelet Product

	Cold stored platelets shelf time
Clinical outcome	≤7 d (n=41)	8–14 d (n=57)	Difference* (95% CI)	P
Principal clinical outcome
24-h mortality	1 (2.4)	2 (3.5)	−1.1% (−10.1,10.1)	0.78
Secondary clinical outcome
3-h mortality	1 (2.4)	2 (3.5)	−1.1% (−10.1, 10.1)	0.78
In-hospital mortality	4/39 (10.3)	5/49 (10.2)	0.1% (−13.5,15.7)	0.99
30-day mortality † ‡	4/39 (10.3)	5/49 (10.2)	0.1% (−13.5, 15.7)	0.99
Mortality from hemorrhage†	3/40 (7.5)	2/56 (3.6)	3.9% (−6.2, 16.9)	0.65
ARDS†	3/40 (7.5)	3/56 (5.4)	2.1% (−8.7, 15.6)	0.69
Allergic/transfusion reaction	0 (0)	0 (0)	−
Thromboembolic events†	4/40 (10.0)	6/56 (10.7)	−0.7% (−0.1, 0.2)	0.91
Initial rapid thromboelastography measurements§ ∥ [median (IQR)]
Activated clotting time (sec)	113 (105,117)	89 (89, 113)	−24 (−31, 0)	0.06
K-time (min)	1.9 (1.45, 2.25)	1.4 (1.2, 2.0)	−0.5 (−1, 0.4)	0.14
Alpha angle (deg.)	70.5 (65, 73)	73 (67, 76)	2.5 (−2, 11)	0.18
Maximal amplitude (mm)	57 (47.2, 62.0)	59.4 (50.9, 64.7)	2.4 (−6.6, 2)	0.27
LY30 (%)	0.3 (0, 1.9)	0.6 (0, 1.2)	0.3 (−0.6, 0.3)	0.84
24-h rapid thromboelastography measurements§ ¶ [median (IQR)]
Activated clotting time (sec)	113 (113, 121)	101 (97, 113)	−12 (−47, 16)	0.41
K-time (min)	1.3 (1.1, 2.3)	2.1 (1.9, 2.2)	0.8 (−2.0, 1.2)	0.33
Alpha angle (deg.)	76 (69, 77)	71 (67, 73)	−5 (−12, 12)	0.31
Maximal amplitude (mm)	57 (51.2, 64.6)	57.3 (53, 65)	0.3 (−6.4, −3)	0.41
LY30 (%)	0.8 (0, 2.1)	0.7 (0, 1.8)	−0.1 (−0.9, 1)	0.78
Initial coagulation measurements
Prothrombin time (sec)#	12.5 (10.8, 13.8)	13 (11.6, 14.5)	0.5 (−1.8, 0.5)	0.25
International normalized ratio**	1.1 (1.1, 1.2)	1.1 (1.0, 1.3)	0 (−0.1, 0)	0.12
24-h coagulation measurements
Prothrombin time (sec)††	14.3 (12.8, 17.1)	14.4 (12.8, 17.2)	0.1 (−2.7, 1.5)	0.64
International normalized ratio‡‡	1.2 (1.1, 1.4)	1.3 (1.1, 1.4)	0.1 (−0.2, 0.1)	0.39
Transfusion requirements within 24 h
Red cells (U)	6 (3, 11)	6 (2, 9)	0 (−2, 3)	0.71
Plasma (U)	4.5 (2.5, 11.5)	4 (2, 8.5)	−0.5 (−1, 3)	0.52
Platelets (U)	2 (1, 4.5)	1 (1, 2)	−1 (−1, 2)	0.08
Whole blood (U)	1.5 (1, 3)	1 (1, 2)	−0.5 (−3, 0)	0.44
Total (U)	11 (5, 21)	9.5 (4.5, 19)	−1.5 (−3, 6)	0.60
Total (mL)	3,432 (1,599, 6,201)	2,881 (1,411, 5,612)	−551 (−845, 1,833)	0.56

OR indicates odds ratio.

^*Difference in proportions or medians (Wilcoxon rank-sum test).

^†Excluding subjects who refused participation past 24-hour endpoint.

^‡Patients with attempted follow-up without documented mortality at 30-days and with verified in-hospital survival considered alive (≤7 days, n=9 ; 8–14 days, n=5).

^§Thromboelastography measurements provide viscoelastic properties of a blood sample. Activated clotting time is the time in seconds between initiation of the test and the initial fibrin formation and is increased with factor deficiency or severe hemodilution. The α-angle is the slope of the tracing that represents the rate of clot formation, decreasing with hypofibrinogenemia or platelet deficiency. K-time is the time in minutes needed to reach 20 mm clot strength and is generally increased with hypofibrinogenemia or platelet deficiency. The maximal amplitude is the greatest amplitude of the tracing and reflects platelet contribution to clot strength. LY30 is the percent amplitude reduction at 30 minutes after the maximal amplitude and when elevated reflects a state of hyperfibrinolysis.

^∥Unavailable in 12 patients in the ≤7 days group (n=29) and 21 patients in the 8 to 14 days group (n=36).

^¶Unavailable in 22 patients in the ≤7 days group (n=19) and 30 patients in the 8 to 14 days group (n=27).

^#Unavailable in 20 patients in the ≤7 days group (n=21) and 21 patients in the 8 to 14 days group (n=36).

^**Unavailable in 20 patients in the ≤7 days group (n=21) and 21 patients in the 8 to 14 days group (n=36).

^††Unavailable in 24 patients in the ≤7 days group (n=17) and 34 patients in the 8 to 14 days group (n=23).

^‡‡Unavailable in 24 patients in the ≤7 days group (n=17) and 34 patients in the 8 to 14 days group (n=23).