Control of high density bacterial contamination of the fiberoptic bronchoscope

In a double-blind study the fiberoptic bronchoscope was contaminated with five pathogenic organisms, each at a concentration of 10(9) organisms per milliliter. The shaft and inner channel of the bronchoscope were cleansed with five antiseptic regimens. Each regimen included equal 120-ml aliquots of one, two, or three solutions, respectively. The five different regimens were as follows: (1) physiologic saline solution; (2) 70 percent solution of isopropyl alcohol, followed by physiologic saline solution; (3) alkaline glutaraldehyde, followed by 70 percent solution of isoproply alcohol, followed by physiologic saline solution; (4) benzalkonium chloride, followed by 70 percent isopropyl alcohol, followed by physiologic saline solution; and (5) povidone-iodine solution, followed by 70 percent solution of isopropyl alcohol, followed by physiologic saline solution. The four regimens involving solutions other than saline solution alone were effective in reducing the count of residual bacterial colonies to 10(4) colonies per milliliter or less.