Exposure to blood-containing aerosols in the operating room: a preliminary study.

A personal sampling study was conducted to assess exposure to blood aerosols in the operating room. The breathing zones of primary and assistant surgeons were monitored using a personal cascade impactor configured with three stages corresponding to effective cut-off aerodynamic diameters of 14.8 microns, 3.5 microns, and 0.52 microns, respectively. Hemastix was used to assess the hemoglobin content of each particle size fraction. The arithmetic mean exposure concentration for primary surgeons (n = 14) was 1.4 micrograms Hb/m3 (range, none detected to 7.4 micrograms Hb/m3), while that for assistant surgeons (n = 12) was 1.8 micrograms Hb/m3 (range, 0.3 to 4.8 micrograms Hb/m3). Hemoglobin was detected in Stage 2 in 26 (90%) of the samples, in Stage 5 in 19 (66%) of the samples, and in Stage 8 in 11 (38%) of the samples. These data show that the mucous membrane lining of the upper respiratory tract and alveolar macrophages in the gas-exchange region are likely to be exposed to aerosolized blood in the operating room. Until further research determines the potential of infected blood aerosols to transmit disease, the authors recommend the proper use of respiratory protection equipment instead of surgical masks because the latter do not offer adequate protection.