REPRODUCIBILITY OF URETHRAL PRESSURE PROFILES IN CLINICALLY NORMAL SEXUALLY INTACT FEMALE DOGS BY USE OF MICROTRANSDUCER CATHETERS

Urethral pressures profiles (UPP) obtained by use of microtransducer c atheters were determined in 8 anestrous sexually intact female Beagles during general anesthesia. A upp study consisted of 3 consecutive rec ordings, and 4 upp studies were repeated at an interval of 5 days in e ach dog. Maximal urethral pressure (cm of H2O), bladder pressure (cm o f H2O), and anatomic urethral length (cm) were recorded. Maximal ureth ral closure pressure (cm of H2O) was calculated.Mean +/- SD (for all m easurements) maximal urethral closure pressure was 12.8 +/- 5.6 cm of H2O (range, 2.4 to 25.2 cm of H2O). Maximal urethral closure pressure was significantly (P < 0.05) decreased during the first recording peri od (11.4 +/- 5.8 cm of H2O), compared with the second (13.0 +/- 5.2 cm of H2O) or third (14.1 +/- 5.7 cm of H2O) recording periods within a UPP study (3 consecutive recordings). Mean maximal difference in ureth ral closure pressure during a single UPP study was 4.8 +/- 2.4 cm of H 2O. Significant difference in maximal urethral closure pressure was no t observed between studies. Mean (for all measurements) anatomic ureth ral length was 6.2 +/- 0.9 cm (4.1 to 7.8 cm). Anatomic urethral lengt h was significantly (P < 0.05) less during the first recording period (6.1 +/- 0.9 cm), compared with values for the second and third period s (6.3 +/- 0.9 cm, 6.4 +/- 0.9 cm respectively). Anatomic urethral len gth for time 3 was significantly (P < 0.05) less than the value for ti me 1 (5.8 +/- 0.7 cm vs 6.6 +/- 0.8 cm). We conclude that the microtra nsducer catheter technique for measurement of UPP was reproducible dur ing a single study and between successive studies. This method is usef ul in documenting maximal urethral pressure, maximal urethral closure pressure, and anatomic urethral length in clinically normal sexually i ntact female dogs.