[Evaluation of procedures for vaginal disinfection].

Abstract

At the occasion of the usual preparations preceding gynecological operations the average vaginal bacterial release of 42 patients, already anaesthesized, was assessed by a rinsing technique to be 5,04 +/- 0,98 log10 c.f.u. per ml sampling fluid after aerobic and anaerobic culture. The reduction of this bacterial release caused by the measurement itself is relatively small, therefore the technique was found to be suitable for evaluation of the efficacy of germreducing measures like irrigation or disinfection. An irrigation with isotonic saline during 30 s was measured to reduce the vaginal bacterial release by 0,4 +/- 0,5 log-steps. A solution containing 0,08% chlorhexidine gluconate + 0,1% benzalkon gluconate applicated during 5 min caused a reduction of 1,04 +/- 0,76 and a watery solution of povidone-iodine one of 2,29 +/- 1,00 log-units when used for 3 min. When after disinfection the sustained antimicrobial action of the chlorhexidin-containing preparation was not neutralized already during the sampling process by Tween 80 + lecithine + histidine being contained in the sampling fluid, an erroneously optimistic log reduction of 2,35 +/- 0,48 was measured. From the results it was calculated that 17-23 volunteers are necessary in order to detect with sufficient statistical safety an observed mean log reduction to be 0,5 log-units smaller than a hypothetical minimal reduction of 2,00 log-steps as required provisionally on an arbitrary basis.