Air contamination in open heart surgery with disposable coveralls, gowns, and drapes

The effect of a polypropylene coverall, replacing shirt and trousers, combined with sterile laminated gowns and drapes compared with an all-cotton system was studied in regard to the dispersion of bacteria and particles in a conventionally ventilated operating theater. The operations carried out were open heart procedures in 30 adult patients. Blood agar sedimentation plates were placed in the operative, anesthesia, and perfusion areas. The mean sedimentation values during 1 hour after the start of operation were as follows in the laminate group: 63 colony-forming units (cfu)/m2 in the operative area; 77 cfu/m2 in the anesthesia area; and 143 cfu/m2 in the perfusion area. The corresponding figures in the cotton group were 350 cfu/m2, 364 cfu/m2, and 437 cfu/m2, respectively (p less than 0.0002). At the beginning of the operation, the mean values noted for colony-forming units in the air at the operative site were 8.0 cfu/m3 in the laminate group and 31 cfu/m3 in the cotton group. One hour later, the values were 10 cfu/m3 and 22 cfu/m3, respectively (p less than 0.0002). At the end of the operation, the number of particles 5 microns or larger in the air at the operative site was 278/m3 in the laminate group and 592/m3 in the cotton group. It is concluded that the use of a polypropylene coverall and laminated gowns and drapes significantly reduces the particle and bacterial contamination of the air and the bacterial sedimentation during cardiac operations.