Surgical hand rub: Influence of duration of application on the immediate and 3-hours effects of n-propanol and isopropanol.
BACKGROUND
The recommended duration for surgical hand treatment has been changed from 10 over 5 to 3 minutes and even shorter.


OBJECTIVE
Our objective was to study the impact of the length of surgical hand antisepsis with n-propanol 60% (vol/vol) or isopropanol 70% (vol/vol) applied for 1, 3, or 5 minutes on the reduction of resident hand flora in the setting of the microbiologic laboratory for experimental and applied testing of disinfectants and antiseptics at the Medical University Vienna, Austria, using a Latin Square design.


METHODS
Our methods were according to the Austrian Guidelines for Testing Products for Surgical Hand Antisepsis. The release of bacterial hand flora of 21 subjects is assessed before and immediately after disinfection from one hand and 3 hours later from the other, meanwhile gloved, hand. Mean reduction factors (RF) are calculated.


RESULTS
The immediate mean log(10) RFs with n-propanol or isopropanol were 1.05, 2.03, and 2.30 and 0.74, 1.48, and 2.12, respectively, when applied for 1, 3, or 5 minutes, respectively. After 3 hours, the respective mean log(10) RFs were 0.45, 1.01, and 1.60 and 0.19, 0.79, and 1.03. Thus, with increasing length of application, a highly significant trend (P < .001) toward higher log(10) reductions was demonstrated. At both sampling times, n-propanol was more effective than isopropanol at the corresponding treatments. Furthermore, a highly significant (P < .001) association was found between the individual volunteers and the effect of the antiseptics on their hands.


CONCLUSIONS
The efficacy of surgical antisepsis is significantly associated with the length of application.
Suchomel
Miranda
M
Department of Hygiene and Medical Microbiology, Medical University Vienna, Kinderspitalgasse 15, Vienna, Austria. miranda.suchomel@meduniwien.ac.at
Koller
Walter
W
Kundi
Michael
M
Rotter
Manfred L
ML
D019840:2-Propanol / Q000008:administration & dosage* / Q000494:pharmacology; D000891:Anti-Infective Agents, Local / Q000008:administration & dosage* / Q000494:pharmacology; D001317:Austria; D001419:Bacteria / Q000187:drug effects*; D015169:Colony Count, Microbial; D006225:Hand / Q000382:microbiology*; D006235:Hand Disinfection / Q000379:methods* / Q000592:standards; D006801:Humans; D017053:Infection Control / Q000379:methods; D020005:Propanols / Q000008:administration & dosage* / Q000494:pharmacology; D012016:Reference Values; D013514:Surgical Procedures, Operative / Q000592:standards; D013997:Time Factors
D000891:Anti-Infective Agents, Local; D020005:Propanols; D019840:2-Propanol