(4) Quaternary ammonium compounds (quads). These compounds have
good germicidal activity, but they are neutralized by soap and certain detergents. They
are also absorbed by gauze and fabrics and become diluted.
(5) Phenolic compounds. One of the oldest germicides is carbolic acid and
phenol. Some of its disadvantages are tissue irritation and odor.
(6) Glutaraldehyde (Cidex ). This chemical is more active in a 2-percent
aqueous (water) concentration and is used to disinfect cystoscopies and other lensed
instruments, which are not used beneath body surfaces.
(a) The advantages of Cidex are: it is sporicidal, bactericidal, and
tuberculocidal, it can be used on cemented parts, and it is noncorrosive and won't injure
(b) The disadvantages of Cidex are: long exposure time--10 hours,
caustic to tissue, leaves residue, loses effectiveness after two weeks at room
temperature, and is very expensive.
Cidex is used as a last resort for sterilization.
Table 3-7 provides general information on the usefulness and effectiveness
of chemical disinfectants.