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 t ension (BEOT) would provide an indication of regional (renal) organ pe rfusion in an exsanguination/fluid repletion animal model. Design: Pro spective non-randomized laboratory study. Setting. Research laboratory . Interventions. Eight anaesthetised, spontaneously breathing Sprague- Dawley male rats weighing approximately 200 g were instrumented. They received l-ml aliquots of fluid until no further haemodynamic improvem ent was seen, followed by removal of l-ml aliquots of blood until rena l blood flow fell by 50%. The animal was then resuscitated with repeat ed 1 to 2-ml aliquots of fluid until no further improvement was achiev ed and: finally, progressively exsanguinated to cardiovascular collaps e. Measurements and 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. C hanges in BEOT closely mirrored both systemic (blood pressure and aort ic 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 te nsion. Conclusions. Measurement of BEOT may be a useful and relatively non-invasive means of monitoring regional organ perfusion. Further st udies are warranted.