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Table 1 Pharmacokinetic Parameters of Gentamicin Concentrations in Blood

From: Mannitol and the blood-labyrinth barrier

Parameter Gentamicin (ng/ml) given alone in blood (95%CI) Gentamicin (ng/ml) with mannitol in blood (95%CI) p = 0.433
Ymax 184 (167–200) 172 (132–213)  
k 0.045 (0.025–0.066) 0.055 (0.002–0.109)  
Half life 15.27 (10.5–28.05) 12.50 (6.4–324)  
tau 22.03 (15.1–40.5) 18.03 (9.2–467)  
R 2 0.61 0.26  
  1. Data were fit to a first-order, decreasing exponential as eq. 1: [y(t) = y 0 e kt], to determine pharmacokinetic parameters rate constant k, and concentration at time t when t = 0 h, y0. Fitted parameters did not differ significantly (p = 0.433) with or without mannitol so the best fit gentamicin alone is shown (n = 22 with mannitol and n = 22 without mannitol). As in Figs. 2 and 3, many data points are congruent so they look like one datum. The fitted parameters for eq. 1, (for +/− 95% confidence interval), were y0 = 184 (+/− 167–200) ng/ml; k = 0.045(+/− 0.025–0.066) hrs−1. Parameterized eq. 1 is therefore: y(t) = 184e −0.045t. An alternative way of expressing the rate of decay is the half-life t1/2, which was 15.3 (+/− 10.5–28.05) hours. R2 for these data was 0.61 indicating that about 61% of the variability is accounted for by the model. The finding that parameters k, and y0 were not different with or without mannitol indicate that mannitol did not significantly affect clearance of gentamicin from blood