Table 3.

Rate and risk of excessive or any blood product transfusion according to antiplatelet drug prescription before coronary artery bypass graft surgery

Outcome	Antiplatelet drug(s) prescribed	No. (%) with outcome	Crude OR (95% CI)	Adjusted OR (95% CI)**
Excessive transfusion*	Neither	260 (52.4)	1.0	1.0
	Aspirin alone	58 (55.8)	1.1 (0.8–1.8)	1.0 (0.6–1.6)
	Clopidogrel alone	6 (54.6)	1.1 (0.3–3.6)	0.7 (0.2–2.5)
	Aspirin and clopidogrel	33 (71.7)	2.3 (1.2–4.5)	2.2 (1.1–4.3)
Any transfusion	Neither	300 (60.5)	1.0	1.0
	Aspirin alone	70 (66.7)	1.3 (0.8–2.0)	1.1 (0.7–1.7)
	Clopidogrel alone	9 (81.8)	3.0 (0.6–13.8)	1.8 (0.4–9.2)
	Aspirin and clopidogrel	36 (78.3)	2.4 (1.2–4.9)	2.1 (1.0–4.5)

* Defined as a transfusion of ≥ 2 units of non-autologous packed red blood cells, ≥ 2 units of fresh frozen plasma, ≥ 5 units of cryoprecipitate, or ≥ 5 units of platelets, during CABG and up to the second post-operative day. ** Adjusted for age, sex and receipt of 1 or more units of autologous whole blood perioperatively. OR odds ratio; CI confidence interval