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Updated: Feb 1, 2026

The Microfluidic Probe: Operation and Use for Localized Surface Processing
Published on: June 4, 2009
Surface contamination in the operating room: use of adenosine triphosphate monitoring
Alex Ramirez1, Sanjay Mohan2, Rebecca Miller1
1Department of Anesthesiology and Pain Medicine, Nationwide Children's Hospital, 700 Children's Drive, Columbus, OH, 43205, USA.
Purpose:
We prospectively investigated contamination of high-contact surfaces in the operating room (OR) using adenosine triphosphate (ATP) monitoring. We tested whether contamination would increase from morning (AM) to afternoon (PM), despite cleaning between cases. Second, we compared the degree of OR contamination to non-OR control sites.
Methods:
ORs with high case volumes were selected for the study. Ten sites in each OR were swabbed using the AccuPoint® HC ATP Sanitation Monitoring device, which provided a numerical measure of contamination (relative light units, RLUs). According to the manufacturer, surfaces are considered clean at ≤ 400 RLUs. AM measurements were taken before the start of surgical cases and PM measurements were taken after cases were completed.
Results:
Eighty morning and 70 afternoon samples were obtained from 8 ORs. Apart from the OR floor, laryngoscope handles had the highest level of morning contamination (1204 RLUs, interquartile range 345, 2603), with 75% of AM samples and 100% of PM samples exceeding 400 RLUs. This contamination was comparable to hospital toilet seats (87% of samples exceeding 400 RLUs). No sites showed statistically significant increases in contamination from AM to PM.
Conclusion:
Apart from the OR floors, laryngoscope handles emerged as a key OR site where improved cleaning practices may reduce cross-contamination risk. While some sites showed increased contamination over the course of the day, none of these met statistical significance thereby offering tentative evidence that current cleaning practices during case turnover are effective for most sites.
Insights
High-contact surfaces like laryngoscope handles in operating rooms (ORs) show significant contamination, comparable to toilet seats. Current cleaning practices appear effective between surgical cases, preventing significant contamination increases throughout the day.
Area of Science:
- Healthcare-associated infections
- Environmental hygiene
- Surgical site infection prevention
Background:
- Operating room (OR) contamination poses a risk for healthcare-associated infections.
- Adenosine triphosphate (ATP) monitoring is a rapid method to assess surface cleanliness.
Purpose of the Study:
- To investigate operating room (OR) surface contamination using adenosine triphosphate (ATP) monitoring.
- To determine if contamination levels increase from morning (AM) to afternoon (PM) despite cleaning between cases.
- To compare OR contamination levels with non-OR control sites.
Main Methods:
- Prospective study in 8 ORs with high case volumes.
- ATP monitoring (AccuPoint® HC) used on 10 high-contact sites per OR.
- Samples collected pre-surgery (AM) and post-surgery (PM); surfaces with >400 relative light units (RLUs) considered contaminated.
Main Results:
- Laryngoscope handles showed high AM contamination (1204 RLUs), with 75% of AM and 100% of PM samples exceeding 400 RLUs.
- OR floor contamination was high, but laryngoscope handle contamination was comparable to hospital toilet seats (87% >400 RLUs).
- No statistically significant increase in contamination was observed from AM to PM at any site.
Conclusions:
- Laryngoscope handles are a critical site for potential cross-contamination, warranting improved cleaning protocols.
- Current cleaning practices between surgical cases appear effective in preventing significant contamination increases throughout the day for most OR sites.
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