Table 1.

Parameter values for theoretical calculations.

Symbol	Meaning	Value
r0	Inner radius of catheter	0.03 cm
rc	outer radius of catheter	0.045 cm
w	diameter of stylet	2 × 0.02 cm
K	hydraulic permeability of tissue	10−9 cm2
L	length of porous region of catheter	5 cm
Q	total flow rate out of catheter	1.25 mL/min
η	viscosity of fluid (water)	0.01@25C dyne – sec/cm2
A	(internal) area of catheter lumen	0.096 mm2
Kcath	hydraulic permeability of catheter lumen	0.038 mm2
Λ	boundary value (see text)	$\frac{\eta Q}{A{K}_{\text{cath}}}$