A randomised prospective comparison of Rotecno versus new Gore occlusive surgical gowns using bacterial air counts in ultraclean air.

Ultraclean air (UCA) in operating theatres is defined as <10 colony-forming units (cfu)/m(3). The current European standards for surgical gowns are contained in EN13795 but these do not include containment of bacterial dispersal as a standard test. A trial in 2003 found that there were bacterial air counts of 1 cfu/m(3) with Rotecno gowns and 0.5 cfu/m(3) with body exhaust suits in total knee arthroplasty (TKA). This study compared bacterial air counts using Rotecno gowns with a new type of occlusive gown made from Gore liquid-proof fabric, which were superior to the Rotecno gowns on standard EN13795 laboratory testing. Fifty-six joint replacements were allocated randomly either to Rotecno or to Gore gowns with stratification into TKA, total hip arthroplasty (THA) or revision THA. Airborne bacteria were collected from within 30 cm of the wound for the first 10 min of surgery using a Casella slit sampler. The new gowns were associated with higher air counts (3.7 cfu/m(3)) than the Rotecno gowns (1.2 cfu/m(3)) (P<0.001). Three of the Gore samples exceeded the clean air standard of 10 cfu/m(3). In TKA patients, the existing Rotecno gowns, now many years old, had higher air counts (2.0 cfu/m(3)) than in the 2003 trial (0.8 cfu/m(3)) (P<0.001). The new gowns were superior in standard laboratory tests but not superior at preventing airborne bacterial dispersal. Rotecno gowns, although many years old, were still effective. This study highlights the importance of testing new materials in a clinical environment with UCA; in-vitro testing alone is probably not an adequate assessment.