A double-blind, randomized controlled trial of cystometry using saline versus 0.3 M potassium chloride infusion in women with overactive bladder syndrome.

AIM: To evaluate the effect of 0.3 M potassium chloride on cystometric parameters by comparing it with normal saline as a filling solution in women with overactive bladder (OAB). PATIENTS AND METHODS: Twenty-three women with significant OAB symptoms underwent consecutive cystometrograms (CMGs) using 0.9% normal saline (NS) and 0.3 M potassium chloride (KCl), the order of which was randomized for each patient. Individual CMGs were performed by separate investigators and both patients and investigators were blinded to the order in which each solution was given and to the results of the other CMG. RESULTS: Regardless of the nature of the filling solution, the order in which the CMGs were performed had little influence on either first desire to void (FDV, mean 83.5 ml vs. 117.8 ml for first and second CMGs respectively, P = 0.10) or on maximum cystometric capacity (Cmax, mean 265.0 ml vs. 264.4 ml, P = 0.98). KCl produced a significant (24%) reduction in mean Cmax compared to NS (mean 228.6 ml vs. 300.8 ml, P = 0.001), irrespective of the order of infusion. CONCLUSION: This comparative study using 0.3 M KCl versus NS as filling solutions suggests that intravesical potassium may not simply act on urothelial sensory nerve endings; it may also stimulate detrusor muscle contraction. These findings may influence the interpretation of the potassium sensitivity test in patients with OAB symptoms, particularly in those suspected of having interstitial cystitis.

Interstitial cystitis versus detrusor overactivity: a comparative, randomized, controlled study of cystometry using saline and 0.3 M potassium chloride.

PURPOSE: We compared cystometric findings in interstitial cystitis and detrusor overactivity using 0.3 M KCl and 0.9% normal saline. MATERIALS AND METHODS: Female patients with established diagnoses of IC (7 patients according to NIDDK criteria) and urodynamically proven DO (10 patients) underwent consecutive cystometrograms using 0.9% normal saline and 0.3 M KCl, the order of which was randomized for each patient. Individual CMGs were performed by separate investigators, and patients and investigators were blinded to the order in which the solutions were used and to the results of the other CMG. The results were analyzed on a comparative basis using a 2-tailed t test for comparison of the means and a Kolmogorov-Smirnov z test was used for group comparison. A ROC curve was used to plot sensitivity to the false-positive rate. RESULTS: Irrespective of the diagnosis or the type of infusion used, the volume at FDV was slightly lower with the first CMG compared to the second (mean 76.1 vs 94.2 ml) but did not reach statistical significance (p = 0.20). However, Cmax was similar for first and second CMGs (mean 214 vs 213.2 ml, p = 0.98). Although lower with KCl, there was no significant difference in FDVs obtained with either solution (mean 78.2 vs 92.2 ml for KCl and NS, respectively, p = 0.33). However, KCl produced a significant reduction in Cmax across the whole group (mean 244.5 vs 182.7 ml, p = 0.008). This was most marked in the DO group in which there was a 23% reduction in Cmax with KCl compared to NS, while the IC group showed only a 15% reduction in mean Cmax. The ROC curve, comparing Cmax values for NS with KCl cutoff values of 15% and 30%, resulted in poor positive predictive values (51% and 66%, respectively) for comparative cystometry in distinguishing IC from DO. CONCLUSIONS: The 0.3 M KCl reduces Cmax in IC and DO, the effect being more pronounced in DO. Urothelial hyperpermeability is not specific to IC. Comparative cystometry using NS and 0.3 M KCl does not help to differentiate IC from DO.

Degree vs diploma education: increased value to practice.

Graduate education for nursing and midwifery has been debated for some years, with current opinion in favour of at least an increase in degree provision (Nursing and Midwifery Council (NMC), 1999). The professions as well as consumers and purchasers of nursing and midwifery education need to be sure, however, that they are getting "added value" with the graduate practitioner. Educationalists identify "critical thinking" as the level that distinguishes diploma from graduate preparation. This article intends to clarify whether academic achievements are restricted to the theoretical aspects of the award or whether a degree adds value to clinical practice. The study design was an experimental case-control cross-sectional survey carried out on samples of nursing and midwifery graduates and diplomates. The graduates were grouped as experimental cases, while the diplomates were controls. A measurement tool of 42 items covering a range of attributes and skills was employed in the study to provide a rating score for individual samples. Statistical analysis was carried out and showed that the scores from graduates were significantly different from the diplomates, indicating that there are genuine differences between the graduates and diplomates. Furthermore, from discriminant analysis of item scores, it appeared that the graduates' overall item scores were higher than the diplomates as indicated by the centroid of the functions being positive for the graduates and negative for the diplomats. The evidence from this study seems to support current thinking that a degree adds value to practice.