[The sterilization effect of formaldehyde fumigating on the catheter place vertically].

Unlabelled: The aim of this paper is to investigate the effect of formaldehyde fumigating on the sterilization of catheters with different diameters and placed in different positions. The lumen of cleaned catheters with different diameters was filled with a solution of live bacilli coil. The catheters were then dried by a drier and divided into 3 groups for formaldehyde fumigating sterilization. A segment of 5 cm of the middle section of the sterilized catheters was cut and incubated at 36 degrees C for 48 h with bouillon medium. For those segments with positive culture, bacteriologic identification was done.

Results: Group A, U = 6.85 and P < 0.01; Group B, chi 2 = 8 and P < 0.01; Group C, chi 2 = 13, P < 0.01.

Conclusions: in the same conditions, fumigating in vertical direction is better than fumigation in horizontal direction and save time; in the same conditions, the positive culture rate is inversely related to the diameter of the catheters; for catheter with a diameter greater than 0.75 cm, fumigating vertically for 2 h is enough to obtain satisfactory sterilization effects.