Pharmacokinetics of epinephrine in patients with septic shock: modelization and interaction with endogenous neurohormonal status

Table 3 Population pharmacokinetic parameters of epinephrine in 38 patients with septic shock and bootstrap statistics

Parameter	Mean	SE (%)	Median^a	5^th to 95^th percentiles^a
CL (L/hr/70 kg BW/50 SAPS II units)	127	6.0	125	115 to 140
V (L)	7.9	36	7.4	1 to 13
R0 (nmol/h)	43.5	24	43	1 to 65
θ_BW effect on CL	0.60	33	0.59	0.23 to 0.95
θ_{SAPS II} effect on CL	-0.67	21	-0.65	-0.91 to -0.43
BSV(CL) (square root of ω²_CL)	0.33	31	0.30	0.20 to 0.39
BSV(R0) (square root of ω²_R0)	1.23	20	1.23	1 to 2.85
Residual variability, proportional component	0.1^b	NA	NA	NA
Residual variability, additive component, nmol/L	0.1^b	NA	NA	NA

^aStatistics from 387 bootstrap runs (13 abnormal termination runs). Non parametric 90% confidence interval based on the 5^th to 95^th percentiles.
^bFixed values.
BSV = between subject variability; BW = body weight; CL = epinephrine clearance; NA = not applicable; R0 = baseline rate of epinephrine infusion; SAPS II = new simplified acute physiology score; SE (%) = standard error of estimate in %; V = epinephrine distribution volume.
θ_BW effect on CL, CL = 127 (BW/70)^0.60, the individual CL increases or decreases as a function of BW, it is > 127 L/hr if BW is > 70 kg and < 127 L/hr if BW < 70 kg. θ_SAPSII effect on CL, CL = 127 (SAPSII/50)^-0.67, the individual CL increases or decreases as a function of SAPS II score, it is > 127 L/hr if SAPS II is < 50 and < 127 L/hr if SAPS II > 50 units.

ISSN: 1364-8535