Table 6.

Summary of key pre-analytical recommendations about storage conditions

Storage conditions	Store samples at room temperature (15–25 °C) until analysis.
	Perform whole blood assays <4 h after blood sampling and centrifugation <1 h.
	Extremes of temperature (e.g. both refrigerated or high) should be avoided.
	Store PPP at room temperature (15–25 °C) or at −80 °C until analysis.
	If the whole blood sample is centrifuged within 1 h of collection, the plasma can be left on top of the cells at room temperature up to 4 h prior to testing.
	Time from sampling to analysis depends on analyte: Samples for PT/INR have longer stability (24 h) at room temperature. Samples for aPTT should be performed using fresh plasma <4 h (<1 h in patients treated with unfractionated heparin). For platelet function assays, samples should rest at room temperature for at least 15 min before analysis. Testing should be completed <3–4 h of collection. For factors V and VIII analyses should be performed <3 h. Fibrinogen, protein C and antithrombin activity appear to remain relatively constant when stored at room temperature for up to 7 days. Protein S activity is unstable, with a statistically significant loss of activity at 8 h. VWF appears to be stable at room temperature for 48 h.