In a recent surgery, one
author of this study noted
poor urine flow after kidney
reperfusion in a liver kidney
transplant patient; however,
after straightening the urine
drainage tubing to empty the
urine that had accumulated in
the generally U-shaped dependent
loop in the Foley drainage
tube, the rate of urine outflow
from the bladder appeared to
increase. This sequence of events
raised a simple question with
clinical implications: could
potentially harmful back-pressures
sometimes exist in urine
drainage systems that are considered as passive drains that reliably
channel urine from the bladder
to the urine collection bag? At
a minimum, obstruction to urine
outflow may cause patient discomfort
and may also predispose
a patient to a catheter-associated
urinary tract infection (CAUTI).
Informal experimentation with a
commercial urine drainage system
led to the hypothesis that significant
back-pressures might
arise in clinical practice, and consequently,
to the bench experiments
described herein.