Chlorhexidine Against Sodium Hypochlorite as Skin Antiseptics

Cultures were taken with a scrub-cup of 5cm2 of internal area pressed over the skin previously prepared, then it was added a 3mL of culture broth (C/E neutralizing broth (D/E Neutralizing Broth, DIFCO TM) containing a neutralizing agent and a detergent agent (1% solution tween-80) as washing solution. The skin was scrub with a sterile rubber policeman for 2 minutes, and the procedure was conducted once again. Both aliquots were gathered together in a sterile tube, and a sample of 50mL was spread in a plate containing a neutralizing agar (D/E neutralizing Agar, DIFCO TM) and incubated at 35°C for 72 hrs. After incubation, the colonies were counted.

Two antiseptics (2% chlorhexidine gluconate in 70% isopropyl alcohol and 10% sodium hypochlorite) and two controls were tested as skin antiseptics. The intervention consisted of preparing four skin's areas with the antiseptic or the control, two in each arm of the volunteer. These ones were approximately 25cm2 on the forearm for each antiseptic or control. The antiseptic or control were applied in an outward circular motion using a swab that was soaked with the solution. The solution was kept on the skin for 60 seconds before the bacterial culture was conducted. Every volunteer were studied in three separate occasions, alternating the four areas in every subsequent test, so every area was studied with each control or antiseptic.

Three antiseptics will be tested: 2% chlorhexidine gluconate in 70% isopropyl alcohol, 10% sodium hypochlorite and 10% povidone-iodine, each one will be applied on the surface of one fingertip each, and will be allow to dry for 60 seconds, then the remaining antiseptic on the skin will be wash out with distilled water. The evaluated zones will be dried with sterile gauze, and then will be covered with sterile gauze for two hours. After this period, each finger will be placed for 30 seconds on an agar plate, which will be inoculated whit an ATCC E. coli. The plate will be incubated at 35ºC for 72 hrs. After incubation, a blinded technician will report the presence or absence of bacterial growth