Bladder epithelial oxygen tension--a new means of monitoring regional perfusion? Preliminary study in a model of exsanguination/fluid repletion.
OBJECTIVE
To assess whether monitoring of bladder epithelial oxygen tension (BEOT) would provide an indication of regional (renal) organ perfusion in an exsanguination/fluid repletion animal model.


METHODS
Prospective non-randomized laboratory study.


METHODS
Research laboratory.


METHODS
Eight anaesthetised, spontaneously breathing Sprague-Dawley male rats weighing approximately 200 g were instrumented. They received 1-ml aliquots of fluid until no further haemodynamic improvement was seen, followed by removal of 1-ml aliquots of blood until renal blood flow fell by 50%. The animal was then resuscitated with repeated 1 to 2-ml aliquots of fluid until no further improvement was achieved and, finally, progressively exsanguinated to cardiovascular collapse.


RESULTS
A continuous Clark-type oxygen electrode lying in contact with the inside wall of the bladder measured changes in BEOT during these exsanguination and fluid repletion manoeuvres. Changes in BEOT closely mirrored both systemic (blood pressure and aortic blood flow) and regional (renal blood flow) haemodynamic changes. A direct correlation existed between percentage change in BEOT and base deficit, and an indirect correlation was seen with arterial oxygen tension.


CONCLUSIONS
Measurement of BEOT may be a useful and relatively non-invasive means of monitoring regional organ perfusion. Further studies are warranted.
Singer
M
M
Bloomsbury Institute of Intensive Care Medicine, University College London Medical School, Rayne Institute, UK.
Millar
C
C
Stidwill
R
R
Unwin
R
R
D000818:Animals; D004195:Disease Models, Animal; D004848:Epithelium; D005440:Fluid Therapy; D006470:Hemorrhage / Q000378:metabolism; D008297:Male; D008991:Monitoring, Physiologic / Q000295:instrumentation / Q000379:methods*; D010100:Oxygen / Q000378:metabolism*; D011446:Prospective Studies; D051381:Rats; D012039:Regional Blood Flow; D001743:Urinary Bladder / Q000098:blood supply / Q000166:cytology / Q000378:metabolism*
D010100:Oxygen