Table 2.

Univariate regression analysis to determine predictors (p < 0.15) of allogeneic blood transfusion and each type of excessive postoperative blood loss in the study patients.

Variables	BT			THL > 2.7 mg/dL			ETBL > 348.6 mL			DV/kg > 10.6 mL/kg
	Odds ratio	95% CI	p value	Odds ratio	95% CI	p value	Odds ratio	95% CI	p value	Odds ratio	95% CI	p value
Age	1.021	0.955 to 1.091	0.54	0.996	0.949 to 1.046	0.879	0.959	0.916 to 1.005	0.08♯	1.019	0.969 to 1.070	0.47
Male gender	1.050	0.289 to 3.819	0.94	1.207	0.466 to 3.123	0.699	5.009	2.269 to 11.060	0.0001♯	2.250	0.962 to 5.261	0.06♯
Right side	1.827	0.647 to 5.163	0.26	0.727	0.335 to 1.581	0.421	0.794	0.371 to 1.698	0.55	0.849	0.393 to 1.834	0.68
Weight	0.948	0.903 to 0.996	0.03	0.986	0.953 to 1.019	0.394	1.060	1.027 to 1.093	0.0003♯	0.946	0.911 to 0.983	0.004♯
Height	1.025	0.962 to 1.099	0.45	0.997	0.947 to 1.049	0.893	1.119	1.065 to 1.175	<0.0001♯	1.010	0.961 to 1.061	0.70
BMI	0.809	0.701 to 0.934	0.004♯	0.964	0.879 to 1.057	0.437	1.052	0.969 to 1.143	0.22	0.811	0.725 to 0.907	0.0002♯
Antiplatelet agent use	1.082	0.235 to 4.975	0.92	0.532	0.121 to 2.341	0.404	0.238	0.031 to 1.807	0.17	0.858	0.246 to 2.998	0.81
ASA physical status grade 3-4	1.245	0.440 to 3.519	0.68	0.771	0.358 to 1.661	0.507	0.615	0.288 to 1.311	0.21	0.771	0.358 to 1.661	0.51
CCI	1.141	0.694 to 1.875	0.60	0.931	0.634 to 1.367	0.714	0.811	0.552 to 1.191	0.29	0.895	0.609 to 1.317	0.57
Comorbidities
HT	0.895	0.279 to 2.868	0.85	1.168	0.455 to 2.992	0.748	0.670	0.292 to 1.539	0.35	0.937	0.382 to 2.296	0.89
RA	n/a			n/a			n/a			n/a		0.99
Femorotibial angle	0.980	0.901 to 1.066	0.64	1.01	0.953 to 1.071	0.734	0.983	0.924 to 1.046	0.58	0.986	0.927 to 1.050	0.67
OA KL grade 4	1.589	0.499 to 5.058	0.43	0.982	0.439 to 2.199	0.960	0.883	0.403 to 1.935	0.76	1.402	0.598 to 3.287	0.44
Preoperative ROM	1.028	0.998 to 1.060	0.07♯	1.007	0.987 to 1.028	0.490	1.024	1.002 to 1.046	0.03♯	1.021	0.999 to 1.044	0.06♯
Preoperative laboratory values
Hb	0.257	0.144 to 0.459	<0.0001♯	2.226	1.556 to 3.184	<0.0001♯	1.894	1.355 to 2.647	0.0002♯	1.200	0.872 to 1.652	0.26
Platelet count	0.997	0.990 to 1.004	0.37	1.003	0.999 to 1.008	0.118♯	0.999	0.994 to 1.004	0.69	0.995	0.990 to 1.001	0.09♯
aPTT	0.963	0.779 to 1.190	0.73	0.967	0.823 to 1.135	0.678	1.044	0.895 to 1.217	0.59	0.974	0.830 to 1.144	0.75
INR	26313.398	14.063 to 49234185.914	0.008♯	0.182	0.000 to 156.350	0.621	0.476	0.001 to 335.973	0.82	0.231	0.000 to 193.500	0.67
CrCl	0.969	0.942 to 0.996	0.03♯	1.003	0.987 to 1.019	0.765	1.026	1.011 to 1.040	0.0006♯	0.981	0.963 to 1.001	0.06♯
Albumin	0.867	0.759 to 0.989	0.03♯	0.992	0.892 to 1.102	0.877	0.969	0.874 to 1.075	0.55	1.116	0.998 to 1.247	0.05♯
General anesthesia	1.191	0.147 to 9.631	0.87	1.355	0.292 to 6.279	0.698	1.301	0.281 to 6.021	0.74	1.355	0.292 to 6.279	0.70
Operative time	0.965	0.931 to 1.001	0.05♯	0.998	0.975 to 1.021	0.838	0.990	0.968 to 1.014	0.41	0.998	0.975 to 1.021	0.84
Large prosthesis size	0.831	0.260 to 2.653	0.76	1.368	0.608 to 3.078	0.448	4.522	2.071 to 9.875	0.0002♯	2.616	1.203 to 5.690	0.02♯

BT: blood transfusion; THL: total hemoglobin loss; ETBL: estimated total blood loss; RD/kg: drainage volume per kg; CI: confidence interval.

BMI: body mass index; ASA: American Society of Anesthesiologist; CCI: Charlson Comorbidity Index,

HT: hypertension; RA: Rheumatoid arthritis; OA: osteoarthritis; KL: Kellgren-Lawrence; ROM: range-of-motion,

Hb: hemoglobin; aPTT: activated partial thromboplastin time; INR: international normalized ratio; CrCl: creatinine clearance.

♯: significant value with p < 0.15.