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Microbial isolations from maxillofacial operation theatre and its correlation to fumigation in a teaching hospital in
Rishi Bali1, Parveen Sharma1, Saurabh Nagrath1
1Department of OMFS, D.A.V. Dental College and M.M. General Hospital, Yamunanagar, 135001 India ; Pt. B.D. Sharma University of Health Sciences, Rohtak, Haryana India.
Abstract:
Postoperative infection and sepsis remain a major cause of morbidity among patients undergoing surgery. Maintenance of strict asepsis is essential if post-operative infection and its consequences are to be minimized. In developing countries maintenance of asepsis in most operation theatres is limited to fumigation and mopping. Clinical trials have confirmed that 80-90 % of bacterial contaminants found in wound after surgery come from microbes present in air of operating theatre. A study was conducted to evaluate the microbiological contamination of maxillofacial operation theatres in India and its correlation to weekly fumigation. A total of 6,723 culture plates, including 2,241 air and 4,482 swab samples were studied. Samples were collected at prefumigation, midcycle and post-fumigation stages and were cultured over three different medias. Predominant bacteria identified were Staphylococcus aureus (76 out of 83 samples by active air sampling) followed by Streptococcus while Aspergillus was the main fungal isolate. Formaldehyde based fumigation decreased the colony forming units (cfu/m(3)) of all organisms in different samples and was found to be highly effective against Fungi and E. coli. Literature suggests that for conventional operating theatres the bioload should not exceed 35 cfu/m(3) in an empty theatre. In our study the cfu levels were always lower immediately after fumigation was carried out; however they moved up beyond this limit as the days passed. This implies that once a week fumigation with formaldehyde is less than optimal to achieve acceptable levels of disinfection.
Insights
Weekly formaldehyde fumigation in Indian maxillofacial operation theatres is insufficient for maintaining optimal microbial control. Bacterial and fungal contamination levels rise above recommended limits shortly after fumigation, indicating a need for more frequent disinfection protocols.
Area of Science:
- Microbiology
- Infection Control
- Surgical Safety
Background:
- Postoperative infection and sepsis are significant causes of surgical morbidity.
- Maintaining asepsis in operation theatres is crucial for minimizing infection risks.
- Current disinfection practices in developing countries often rely on fumigation and mopping.
Purpose of the Study:
- To evaluate microbiological contamination in Indian maxillofacial operation theatres.
- To assess the correlation between contamination levels and weekly formaldehyde fumigation.
- To determine the efficacy of formaldehyde fumigation against airborne and surface microbes.
Main Methods:
- A comprehensive microbiological study involving 6,723 culture plates (2,241 air, 4,482 swab samples).
- Samples collected at prefumigation, midcycle, and post-fumigation stages.
- Culturing over three different media to identify bacterial and fungal contaminants.
Main Results:
- Staphylococcus aureus was the predominant bacteria (76/83 samples), followed by Streptococcus.
- Aspergillus was the primary fungal isolate.
- Formaldehyde fumigation effectively reduced colony-forming units (cfu/m³) for most organisms, especially fungi and E. coli.
Conclusions:
- While formaldehyde fumigation temporarily reduces microbial load, weekly application is suboptimal for maintaining acceptable disinfection levels.
- Contamination levels increased significantly between fumigation cycles, exceeding the recommended 35 cfu/m³.
- Enhanced or more frequent disinfection strategies are necessary for effective control of operation theatre contamination.
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