Evaluation of third generation
quaternary ammonium compounds for the sterilisation of operation theatre
Rajkumar B1, Sasivannan2,
Kannan I3
1Dr. Rajkumar Bharani, Associate Professor, Department of surgery, 2Dr.
Sasivannan, Associate Professor, Department of surgery, 3Dr. I. Kannan,
Associate Professor, Department of Microbiology; all are affiliated to
Tagore Medical College and Hospital, Rathinamangalam, Chennai, INDIA
Address for
Correspondence : Dr. I. Kannan, Associate Professor,
Department of Microbiology,Tagore Medical College and Hospital,
Rathinamangalam, Chennai, India, E. mail: kannan_iyan@tagoredch.in
Abstract
Introduction:
Sterilisation of operation theatre is the global method in the
prevention of surgical wound infections. In recent years the first and
second generation compounds are replaced by the third generation
quaternary ammonium compounds. The efficacy of these compounds is still
doubtful. Aim:
An attempt has been in the present study to evaluate the third
generation quaternary ammonium compounds for its efficacy in
sterilisation of operation theatre. Methods:
The samples were collected before and after fogging. Quaternary
Ammonium Compound D-125 is used in the present study. The presence of
bacteria in the indoor air was sampled by plate exposure method. The
brain heart infusion agar plate was kept open for 15 minutes at the
height of one metre from the level of ground. For the analysis of
surface contamination, the sampling was done by swabbing the surface.
The swabs were inoculated into Robertson cooked medium (HIMEDIA) and
were incubated 37OC for seven days in anaerobic condition. Results: The results
showed the complete removal of microorganism after 45 minutes of
fogging. Conclusion:
The present study has showed that the quaternary ammonium compounds are
effective disinfectant and sterilisation agent in the sterilisation of
operation theatre.
Key words:
Operation Theatre Sterilisation, Quaternary Ammonium Compounds, Spread
Plate Methods, Surface Contamination
Manuscript received:
22nd Feb 2015, Reviewed:
7th Mar 2015
Author Corrected:
17th Mar 2015, Accepted
for Publication: 3rd Apr 2015
Introduction
The postoperative bacterial contamination and infection of the surgical
wound is the major risk factor during the surgery [1]. Sterilisation of
operation theatre is the global method in the prevention of surgical
wound infections.
The increase in the incidence of Methicillin resistant Staphylococcus
aureus (MRSA) and vancomycin resistant Enterococcus (VRE) in the
hospital environment has raised lot of concern in the sterilisation of
hospital environment especially operation theatre [2-5]. The operation
theatre is a closed environment and has every chance of contamination
during surgery by the patient and theatre staff members. The studies
have shown that the predominant bacterial contamination is coagulase
negative staphylococcus followed by Staphylococcus aureus [6]. It is
also found that the nasopharyngeal shedding of the patient and theatre
staff members are the main reasons for the contamination [7].
Conventional method of sterilisation of operation theatre is fumigation
by formaldehyde gas as it is effective in killing even the bacterial
spores [8, 9]. However the toxicity and carcinogenicity of formaldehyde
gas have raised a lot of concern about the use of it [10]. In recent
years the first and second generation compounds are replaced by the
third generation quaternary ammonium compounds. The efficacy of these
compounds is still doubtful. Hence an attempt has been in the present
study to evaluate the third generation quaternary ammonium compounds
for its efficacy in sterilisation of operation theatre.
Materials
and Methods
It is a cross sectional study conducted in operation theatres of a
tertiary care hospital of 750 bed capacity in Chennai, India.
Fogging
The samples were collected before and after fogging. The sterilisation
agent used is the combination of alkyl dimethyl benzyl ammonium
chloride (2.37%) and alkyl dimethyl ethyl benxyl ammonium chloride
(2.37%) produced under the name of DTcare-125 (Chemtex speciliaty
limited). It is the mixture of quaternary ammonium compounds with other
ingradients like organic silver. It has been recommended for both
disinfection and sterilisation. The product is available as the
concentrated stock solution that can be used to surface sterilise as
well used to sterilise the indoor air.
Quaternary Ammonium Compound D-125 is used at dilution of 1:64 (15ml in
1ltr water) for critical area disinfection such as instruments, OT
tables, lamps, critical contact surfaces etc. It is used at dilution of
1:128 (7.5ml in 1ltr water) for non-critical area disinfection such as
floor mopping, furniture and wall wiping etc. For air disinfection make
a dilution of 1:64 and fog with fogging machine at 1ltr per 1000cft
(28.3 cum).
Sampling and Culture
The operation theatres selected for this study were general surgery,
ENT, OBG, ophthalmology and orthopaedics. The samples were collected
before and after fogging from indoor air and surfaces (OT table, OT
light, instrument trolley, suction apparatus, IV stand,
Boyle’s apparatus, floor and wall) from eight operation
theatres of the hospital.
The presence of bacteria in the indoor air was sampled by plate
exposure method. The brain heart infusion agar plate was kept open for
15 minutes at the height of one metre from the level of ground. Then
the plates were incubated at 37OC for 24 hours in aerobic condition.
The number of colonies grown in the plates was counted and noted.
The sterilisation efficacy of surface was assessed by the removal of
anaerobic bacterial spores which indicates the thorough removal of all
forms of microorganisms. The sampling was done by swabbing the surface.
The swabs were inoculated into Robertson cooked medium (HIMEDIA) and
were incubated 37OC for seven days in anaerobic condition. After seven
days the changes in the media like turbidity and discolouration were
noted. Then the media is gram stained to observe the morphology of
anaerobic bacilli.
Statistical Analysis
The paired student t test was done to find the significance in the
difference in the total number of colonies before and after
sterilisation with SPSS vs 20.0 software.
Results
A total of five operation theatres were selected for the present study.
Both the indoor air and the important surfaces were subjected for
culture before fogging and after fogging.
Table1: Results of plate
exposure method showing the number of bacterial colonies before and
after sterilisation
|
Operation theatre
|
Number of colonies
|
P value
|
|
Before sterilisation
|
After sterilisation
|
|
General surgery
|
4
|
0
|
p<0.001
|
|
ENT
|
3
|
0
|
|
OBG
|
5
|
0
|
|
Ophthalmology
|
4
|
0
|
|
Orthopaedics
|
2
|
0
|
The Table 1 shows the results of bacterial culture analysis
of indoor air of five operation theatre by plate exposure method.
Before fogging all the operation theatres showed the presence of
bacteria in the indoor air. However none of the operation theatres
showed presence of bacteria in the indoor air after fogging.
[Statistically significant, (p<0.001)].
Table 2: Results of plate
exposure method showing the number of fungal colonies before and after
sterilisation
|
Operation theatre
|
Number of colonies
|
P value
|
|
Before sterilisation
|
After sterilisation
|
|
General surgery
|
8
|
0
|
p<0.001
|
|
ENT
|
3
|
0
|
|
OBG
|
6
|
0
|
|
Ophthalmology
|
9
|
0
|
|
Orthopaedics
|
18
|
0
|
The results of fungal culture before and after fogging by
plate exposure method are shown in the Table 2. From the table it is
evident that all the operation theatres showed the presence of fungal
spores before sterilisation but after fogging none of the operation
theatre showed the presence of fungal spores which is statistically
significant (p<0.001).
Table 3: Culture results
of surface sampling from general surgery operation theatre
|
Site of sample
|
Culture result
|
|
Before sterilisation
|
After sterilisation
|
|
OT table
|
Clear
|
Clear
|
|
OT light
|
Clear
|
Clear
|
|
Instrument trolley
|
Clear
|
Clear
|
|
Suction apparatus
|
Turbid
|
Clear
|
|
IV stand
|
Turbid
|
Clear
|
|
Boyle’s apparatus
|
Clear
|
Clear
|
|
Floor
|
Clear
|
Clear
|
|
Wall
|
Clear
|
Clear
|
As far as surfaces are concerned the swabs were analysed for the
presence of bacterial spores, as the surfaces are more liable for the
presence of bacterial spores. The Table 3 shows the culture results of
surface sampling from general surgery operation theatre. Before fogging
the IV stand and suction apparatus showed the presence of anaerobic
spore bearers and all the other sites were free of any spores. However
after fogging, all the sites showed the absence of bacterial spores
Table 4: Culture results
of surface sampling from ENT operation theatre
|
Site of sample
|
Culture result
|
|
Before sterilisation
|
After sterilisation
|
|
OT table
|
Clear
|
Clear
|
|
OT light
|
Clear
|
Clear
|
|
Instrument trolley
|
Clear
|
Clear
|
|
Suction apparatus
|
Clear
|
Clear
|
|
IV stand
|
Clear
|
Clear
|
|
Boyle’s apparatus
|
Clear
|
Clear
|
|
Floor
|
Turbid
|
Clear
|
|
Wall
|
Clear
|
Clear
|
The culture results of surface sampling from ENT operation
theatre are shown in Table 4. The ENT operation theatre showed the
presence of anaerobic spore bearer only on the floor. After
sterilisation, all the sites showed negative for the presence of
bacterial spores.
Table 5: Culture results
of surface sampling from OBG operation theatre
|
Site of sample
|
Culture result
|
|
Before sterilisation
|
After sterilisation
|
|
OT table
|
Turbid
|
Clear
|
|
OT light
|
Clear
|
Clear
|
|
Instrument trolley
|
Clear
|
Clear
|
|
Suction apparatus
|
Clear
|
Clear
|
|
IV stand
|
Clear
|
Clear
|
|
Boyle’s apparatus
|
Clear
|
Clear
|
|
Floor
|
Turbid
|
Clear
|
|
Wall
|
Clear
|
Clear
|
The Table 5 shows the culture results of surface sampling
from OBG operation theatre. Before fogging the floor and OT table
showed the presence of anaerobic spore bearers and all the other sites
were free of any spores. However after fogging, all the sites showed
the absence of bacterial spores.
Table 6: Culture results
of surface sampling from ophthalmology operation theatre
|
Site of sample
|
Culture result
|
|
Before sterilisation
|
After sterilisation
|
|
OT table
|
Clear
|
Clear
|
|
OT light
|
Turbid
|
Clear
|
|
Instrument trolley
|
Clear
|
Clear
|
|
Suction apparatus
|
Clear
|
Clear
|
|
IV stand
|
Clear
|
Clear
|
|
Boyle’s apparatus
|
Clear
|
Clear
|
|
Floor
|
Turbid
|
Clear
|
|
Wall
|
Clear
|
Clear
|
The culture results of surface sampling from ophthalmology
operation theatre are shown in Table 6. The operation theatre showed
the presence of anaerobic spore bearers on the OT light and floor.
After sterilisation, all the sites showed negative for the presence of
bacterial spores.
Table 7: Culture results
of surface sampling from orthopaedics operation theatre
|
Site of sample
|
Culture result
|
|
Before sterilisation
|
After sterilisation
|
|
OT table
|
Clear
|
Clear
|
|
OT light
|
Clear
|
Clear
|
|
Instrument trolley
|
Clear
|
Clear
|
|
Suction apparatus
|
Clear
|
Clear
|
|
IV stand
|
Clear
|
Clear
|
|
Boyle’s apparatus
|
Clear
|
Clear
|
|
Floor
|
Turbid
|
Clear
|
|
Wall
|
Clear
|
Clear
|
The Table 7 shows the culture results of surface sampling from
orthopaedics operation theatre. Before fogging the floor showed the
presence of anaerobic spore bearers and all the other sites were free
of any spores. However after fogging, all the sites showed the absence
of bacterial spores.
Discussion
In the present study an attempt has been made to evaluate the
sterilisation potential of operation theatre. The results obtained are
encouraging as the quaternary ammonium compounds could able to remove
even fungal and bacterial spores from the environment. Many works have
already done regarding the use of quaternary ammonium compounds as
disinfectants and sterilants [11-13]. Quaternary ammonium compounds are
amphoteric surfactants that are widely used for the control of
bacterial growth in clinical and industrial environments [14].
Eventhough the quaternary ammonium compounds are considered to be an
agent of disinfectant, the present study has showed that it could able
to eliminate the bacterial spores. Probably this may be due to the
reason that the bacterial spore contamination in the operation theatres
selected for this study would have at lower level. Bacterial spores are
common in many hospital environments including operation theatre [15].
Hence a good sterilisation agent should be effective sporicidal. Hence
a study should be conducted to find its efficacy in removal of heavily
spore contaminated surfaces.
The use of quaternary ammonium compounds is advantageous as it is
non-irritant and surgeon can resume the routine in 45 minutes after the
fogging. Hence the sterilisation of operation theatre can be performed
after each surgery which cannot be possible with the conventional
aldehyde compounds.
Conclusion
The present study has showed that the quaternary ammonium compounds are
effective disinfectant and sterilisation agent in the sterilisation of
operation theatre. Eventhough in the present study the bacterial spores
are eliminated by the DT-125 in the operation theatre environment, the
question whether they are effective sporicidal agent should be
scientifically evaluated.
Funding:
Nil, Conflict of
interest: None initiated.
Permission from IRB:
Yes
References
1. Whyte W, Hodgson R, Tinkler J. The importance of airborne bacterial
contamination of wound. J Hosp Infect 1982; Jun;3(2):123-35. [PubMed]
2. Bonten MJM, Hayden MK, Nathan C, Voorhis JV, Matushek M, Slaughter
S, et al. Epidemiology of colonisation of patient and environment with
vancomycin-resistant enterococci. Lancet 1996; 348(9042):1615-19. [PubMed]
3. Boyce JM, Potter-Bynoe G, Chenevert C, King T.
Environmental contamination due to methicillin-resistant S.aureus:
possible infection control implications. Infect Control Hosp Epidemiol
1997; Sep;18(9):622-7.
4. Hayden MK, Bonten MJ, Blom DW, Lyle EA, van de Vijver, DA, Weinstein
RA, et al. Reduction in acqusition of vancomycin resistant Enterococcus
after enforcement of routine environment cleaning measures. Clin Infect
Dis 2006; 42(11):1552-60.
5. Bhalla A, Drin D, Donskey CJ. Staphylococcus aureus
intestinal colonization in associated with increased frequency of S.
aureus on skin of hospitalized patients. BMC Infect Dis 2007; 7((105);
108-23.
6. Edmiston C E Jr, Seabrook GR, Cambria RA, et al. Molecular
epidemiology of microbial contamination in the operating room
environment: Is there a risk for infection? Surgery 2005;
Oct;138(4):573-9. [PubMed]
7. Suzuki A, Namba Y, Matsuura M, Horisawa A. Airborne
contamination in an operating suite: report of a five year survey. J
Hyg (London) 1984; 93(202): 567-573. [PubMed]
8. Vesley D, Lauer J, Hawley R. Decontamination,
sterilization, disinfection, and antisepsis. In: Fleming DO, Hunt DL,
editors. Laboratory safety: Principles and practices. 3rd ed.
Washington DC: ASM Press; 2001. p. 383-402. [PubMed]
9. Fink R, Liberman DF, Murphy K, Lupo D, Israeli E.
Biological safety cabinets, decontamination or sterilization with
paraformaldehyde. Am Ind Hyg Assoc J 1988; 49(6):277-9. [PubMed]
10. Rutala WA. APIC guideline for selection and use of
disinfectants. Am J Infect Control 1996; 24(4):313-42. [PubMed]
11. Chaidez C, Lopez J, Castro-del Campo N.Quaternary
ammonium compounds: an alternative disinfection method for fresh
produce wash water. J Water Health. 2007; 5(2):329-33. [PubMed]
12. Jimenez L, Chiang M. Virucidal activity of a quaternary
ammonium compound disinfectant against feline calicivirus: a surrogate
for norovirus. Am J Infect Control. 2006; 34(5):269-73. [PubMed]
13. Chitra Sanjeev Juwarkar. Cleaning and Sterilisation of
Anaesthetic Equipment. Indian J Anaesth. 2013; 57(5):
541–550. [PubMed]
14. Brannon, D. K. Cosmetic microbiology: a practical
handbook. CRC Press, Inc., 1997. Boca Raton, Fla. [PubMed]
15. Kannan I, Jessica Yolanda Jeevitha, Sambandam Cecilia,
Jayalakshmi M, Premavathy RK , Shantha S. Evaluation of surface
contamination of bacteria in various dental clinics with special
reference to obligate and facultative anaerobic spore bearing bacilli.
Int J Med Res Health Sci., 2014; 3(3):554-559.
How to cite
this article?
Rajkumar B, Sasivannan, Kannan I. Evaluation of third generation
quaternary ammonium compounds for the sterilisation of operation
theatre. Int J Med Res Rev 2015;3(3):273-277. doi:
10.17511/ijmrr.2015.i3.051.