Table 1.

Bivariate linear regression analysis of clinical characteristics predictive of free vancomycin concentration

Variablea	βb	SE	P
Age (yr)	0.041	0.036	0.267
Male (n = 19)	−2.262	1.146	0.054
Wt (kg)	−0.006	0.019	0.770
Length of stay prior to sample collection	0.026	0.069	0.709
ICU at sample collection	−1.577	1.488	0.295
APACHE II score	0.237	0.083	0.006
APACHE II < 13 (n = 28)	−3.125	1.074	0.005
History of
Diabetes mellitus (n = 18)	2.624	1.144	0.026
Heart failure (n = 3)	0.468	2.434	0.848
Dialysis (n = 9)	3.334	1.426	0.024
Epilepsy (n = 2)	−3.611	2.905	0.220
Hepatic dysfunction (n = 3)	1.056	2.431	0.666
White blood cell count (n = 46)	0.171	0.072	0.022
Albumin (n = 47)	−0.986	0.885	0.271
Blood urea nitrogen (n = 49)	0.067	0.027	0.017
Blood urea nitrogen ≥ 20 mg/dl (n = 17)	4.346	1.065	<0.001
SCr	0.322	0.162	0.053
SCr ≥ 1.2 mg/dl (n = 25)	3.156	1.063	0.005
CLCR, estimated	−0.030	0.010	0.006
CLCR < 51.815 (n = 25)	3.476	1.042	0.002
Total protein (n = 47)	−1.122	0.580	0.059
Total protein ≥ 6.7 g/dl (n = 16)	−2.957	1.216	0.019
Total bilirubin (n = 47)	0.578	0.179	0.002
Total bilirubin ≥ 1.7 mg/dl (n = 5)	4.706	1.860	0.015
Vancomycin dose	0.002	0.001	0.111
Vancomycin dose ≥ 1500 mg (n = 8)	3.360	1.506	0.031
DOT prior to sample collection (n = 49)	0.117	0.218	0.595
Time postdose (n = 47)	0.214	0.694	0.759
Total [vanco]	0.510	0.020	<0.001
Total [vanco] ≥ 18.4 (n = 11)	7.785	0.829	<0.001
% Protein binding	0.027	0.068	0.694

^an = 50 except where otherwise noted. DOT, duration of therapy.

^bβ, β coefficient.