Airborne bacteria in the operating room can be reduced by HEPA/Ultraviolet air recirculation system (HUAIRS)
Author(s):
David Kirshman, Aerobiotix, Inc., West Carrollton, Ohio; Soumitra Eachempati, Weill Cornell Medical College
Background: Surgical site infections (SSI) are a major cause of morbidity and mortality in US hospitals. Environmental issues such as airborne bacteria in operating rooms may contribute to SSI but this effect has not been well studied. Nonetheless, in Europe but not the US, regulations exist to limit the airborne bacterial levels in the operating theater. A newly available HUAIRS utilizes C-band ultraviolet light focused on a reaction chamber filled with a multitude of clear cylindrical silicate quartz crystals to decrease bacteria from the air. In the first part of a multi-part study, we sought to determine whether airborne bacterial levels can be reduced by a HUAIRS.
Hypothesis: We hypothesized that the HUAIRS could decrease the meaured quantity of airborne bacteria from a functioning surgical theater.
Methods: A newly commercialized HUAIRS (Aerobiotix, Inc., Dayton, OH) was evaluated in its ability to reduce airborne bacteria in a plastic surgery operating room at an outpatient surgery center. An air sampling impactor and agar media plates were placed in multiple locations in the operating room and used to measure the number of colony forming units (CFU) per cubic meter of bacteria in the air before and after the utilization of the HUAIRS. Stats: paired t-test.
Results: The samples of airborne CFU/m3 were measured during surgical procedures over a seven hour sampling period. 12 samples were taken for each of control and HUAIRS periods. The results are as shown below.
|
Sample
|
1
|
2
|
3
|
4
|
5
|
6
|
7
|
8
|
9
|
10
|
11
|
12
|
MEAN
|
|
Control
|
63
|
34
|
10
|
22
|
27
|
15
|
16
|
8
|
22
|
14
|
33
|
22
|
23.8
|
|
HUAIRS
|
11
|
13
|
4
|
14
|
7
|
8
|
11
|
17
|
8
|
11
|
8
|
21
|
11.1
|
Values are expressed in CFU/m3
For the cultured samples obtained, there was a 67.7% (p<0.05) reduction in CFU count in twelve paired samples.
Conclusions: The HUAIRS device significantly decreases the level of airborne bacteria present in the operating room in preliminary study. Further studies will demonstrate whether this actual reduction will translate into a decrease in SSI rate in surgical patients. Environmental concerns may prove to be an important aspect of the overall strategy in reducing SSIs in the future.