Disinfectant use in hospital..

Disinfectant use in hospital..

1. Disinfectant Use In Hospital Dr. Yogita Mistry GMC,Surat

2. Objectives: Definition Categories of disinfectant Factors affecting efficacy of disinfectant Property of Ideal Disinfectant Different disinfectant with few points Use of disinfectant in hospital Use of disinfectant in our hospital

3. Definition Sterilization - is the process that kills all the living micro-organisms including spores , viruses and fungi. Disinfectants –are those germicides or chemical substances which are used to destroy or inhibit the growth of pathogenic vegetative bacteria (not their spores) on inanimate ( nonliving )surfaces such as glassware or surgical instruments. Antiseptics -are those germicides or chemical substances which are used to destroy the pathogenic bacteria (not the spores) on animate (living) surfaces such as skin /mucous membranes.

4. Definition Decontamination - means marked reduction or destruction of viable pathogenic organisms to a level that will allow a healthy persons natural defenses to prevent any infection. Sanitation- means reduction in microbial load from an inanimate surface to a level set forth by public health department.

5. Chemical steriliant: When chemical are used to destroy all forms of microbial life(including spores) , it is called chemical sterilient . For these disinfectant are used with prolonged exposure time.(3-12 hours). High level disinfectant: When a chemical sterilient with same concentration is used for shorter exposoure period, it can kill all microorganisms except large number of bacterial spores. Low level disinfectant: Can kill most vegetative bacteria, some fungi and virus. Intermediate level disinfectant: Might be cidal for mycobacteria , vegetative bacteria, most viruses, most fungi, but not spore.

6. Cleaning: Removal of visible soil (organic and inorganic material) from objects and surface. It is an essential step before high level disinfectant or sterilization.

7. A rational approach to disinfection and sterilization

8. Spaulding believed the nature of disinfection could be understood readily if instruments and items for patient care were categorized as critical, semicritical , and noncritical according to the degree of risk for infection involved in use of the items.

9. Critical Items Critical items confer a high risk for infection if they are contaminated with any microorganisms . Object that enter sterile tissue/vascular system Example: Surgical instruments Cardiac & urinary catheter Implants USG probes used in sterile body cavity

10. Sterile Heat sensitive items: ETO, hydrogen peroxide or Liquid chemical sterilients : 2.4% gluteraldehyde based formulation 0.95% gluteraldehyde + 1.64% phenol / phenate 7.5% stabilized hydrogen peroxide 7.35% stabilized hydrogen peroxide+0.23% peracetic acid 0.2% peracetic acid 0.08% peracetic acid+1% hydrogen peroxide

11. Semicritical Items: Items which contact mucous membrane/ non intact skin Respiratory therapy, anesthesia equipment Laryngoscope blade Esophageal manometry probes Cystoscope As these mucous membrane are usually infected by microorganisms and not by spores. So small no. of spores are permissible. High level disinfectant used for short time/ Intermediate level disinfectant (sodium hypochlorite/ iodophors )

12. Non critical items: Those that come in contact with intact skin but not mucous membrane Bedpans Blood pressure cuff Computers Bedside table, furniture,floor Cleaning at regular interval Mopping with water, detergent, disinfectant(low level disinfectant-phenol/ quternary ammonium componds )

13. Factors affecting the efficacy of disinfectant

14. Number and location of microorganism Innate resistant of microorganisms Bacterial spore> cryptosporidium> mycobacteria > nonlipid /small viruses> fungi> vegetative bacteria> Lipid/medium size virus Gn = Gp Rickettsia , chlamydia , mycoplasma prions

15. Concentration and potency of disinfectant Physical and chemical factors Temperature High pH= Gluteraldehyde , Quternary ammoniym compounds Low pH= Phenol, Hypochlorite, Iodine pH works by altering the disinfectant molecules/cell surface Humidity= effects on gaseous disinfectant( formaldehyde,chlorine dioxide) Water hardness= high cations =make insoluble ppt with disinfectant= decrease killing of organisms

16. Organic and Inorganic matters : Interfere with antimicrobial activity of disinfectant by Chemical reaction between organic materials and disinfectant resulting in a complex formation that are less or no germicidal. By protection of microorganisms from attack Duration of exposure Biofilms Residual proteins and salt

17. Microbial Contamination Of Disinfectant Leads to HAI Not reported with high level disinfectant/ sterilient They are usually not contaminated at point of manufacture, but contaminated during use, storage, dilution

18. Property Of Ideal Disinfectant Broad spectrum : should have a wide antimicrobial spectrum Fast acting: should produce a rapid kill Not affected by environmental factors: should be active in the presence of organic matter (e.g., blood, sputum, feces) and compatible with soaps, detergents, and other chemicals encountered in use Nontoxic: should not be harmful to the user or patient Surface compatibility: should not corrode instruments and metallic surfaces and should not cause the deterioration of cloth, rubber, plastics, and other materials

19. Residual effect on treated surfaces : should leave an antimicrobial film on the treated surface Easy to use with clear label directions Odorless: should have a pleasant odor or no odor to facilitate its routine use Economical: should not be prohibitively high in cost Solubility: should be soluble in water Stability: should be stable in concentrate and use-dilution Cleaner: should have good cleaning properties Environmentally friendly: should not damage the environment on disposal

20. High Level Disinfectant Formaldehyde Gluteraldehyde Orthophtahdehyde Hydrogen peroxide Peracitic acid

21. Formaldehyde Formaldehyde is used as a disinfectant and sterilant both in the liquid and gaseous states. Formaldehyde is sold and used principally as a water-based solution called formalin, which is 37% formaldehyde by weight. The aqueous solution is bactericidal, tuberculocidal , fungicidal, virucidal and sporicidal

22. Formaldehyde Formaldehyde should be handled in the workplace as a potential carcinogen with an employee exposure standard that limits an 8 hour time-weighted average exposure to a concentration of 0.75 ppm . For this reason, employees should have limited direct contact with formaldehyde and these considerations limit its role in sterilization and disinfection processes

23. Formaldehyde MOA: Alkylating amino and sulfhydral groups of proteins and ring nitrogen atoms of purine base Microbicidal action: 2%=Most virus 8%=Poliovirus 4%= Tuberculocidal in 2 minutes for 104 bacilli 2.5% =Salmonella typhi 4%= Sporicidal with 2 hour exposure Use: to prepare viral vaccine (polio, influenza) To preserve anatomical specimen

24. Gluteraldehyde Aldehydes have a wide germicidal spectrum. Gluteraldehydes are bactericidal, virucidal , fungicidal, sporicidal and parasiticidal . They are used as a disinfectant or sterilant in both liquid and gaseous forms. They have moderate residual activity and are effective in the presence of limited amounts of organic material

25. Gluteraldehye High level disinfectant & chemical sterilent Aqueous solution=acidic and not sporicidal , only when it is alkaline “activated” solution and it will be sporicidal Once activated self life is 14 days Newer gluteraldehyde formulation: Gluteraldehyde+phenol + sodium phenate Potentiated acid gluteraldehyde Stabilized alkaline gluteraldehyde

26. MOA: alkylation of sulfhydryl , hydroxyl, carboxy and amino groups of microorganism which alters RNA, DNA, protein systhesis Use: As a high level disinfectant for medical equipment such as endoscope, spirometry tubing, dialyzer, anaesthesia and respiratory equipment S/e: irritant, dermatitis, mucosal irritation, pulmonary syndrome, epistaxis , asthama,rhinitis

27. Hydrogen peroxide MOA: Generate destructive hydroxyl free radical which attack membrane lipid, DNA, essential cell membrane Broad acting Use: stable and effective disinfection of inanimate surfaces 0.5%=Bactericidal & virucidal in 1 minutes, tuberculocidal in 5 minutes 3%=VRE 7%= Sporicidal 6%-25%=Chemical steriliant 13.4%= New rapid acting available

28. Hydrogen Peroxide Stabilized peroxides may also be blended with iodophors or quaternary ammonia. Hydrogen peroxide is also blended with paracetic acid in high concentrations for use as a high-level disinfectant

29. Orthophthaldehyde MOA: interaction with aminoacid , protein, microorganism Excellent microbicidal activity in vitro over a wider pH range as comparable as gluteraldehye Not irritant to eye/nasal mucosa Disadvantage: it will stain the protein gray Use as a high level disinfectant

30. Peracetic acid Rapid action against all microorganisms Enhance the removal of organic material and leaves no residue Remain effective in presence of organic matter and is sporicidal even at low temperatures MOA: denaturation of proteins, disrupt the cell wall permiability Use: as a high level disinfectant for cleaning of endoscopes

31. Intermediate Level Disinfectant Chlorine and chlorine compounds Iodine and Iodophors

32. Chlorine and Chlorine compunds Hypochlorite available as : Liquid(sodium hypochlorite) Solid (calcium hypochlorite) 5.25%-6.25% sodium hypochlorite=House hold bleach Its microbial activity is attributed largely to undissociated hypochlorous acid (HOCL) Dissociation of HOCL depends on pH Disinfectant efficacy of clorine decreases with increase in pH that lead to HOCL=OCL-

33. Chlorine agents are most commonly used due to: Broad spectrum of antimicrobial activity No toxic residue Unaffected by water hardness Inexpensive Fast acting Remove dried/fixed organism and biofilms from surface Low incidence of serious toxicity

34. Hypochlorite's Other disadvantages of hypochlorites include corrosiveness to metals in high concentrations (>500 ppm), inactivation by organic matter, discoloring or “bleaching” of fabrics, and release of toxic chlorine gas when mixed with ammonia or acid.

35. Side effects of household bleach concentration Occular irritation/ oropharyngeal , esophageal gastric burns Discolouration / bleaching of fabrics Release of toxic chlorine gas when mixed with amonia /acid

36. Alternative chlorine compounds are: Demand release chlorine dioxide Sodium dichloroisocyanurate Chloramine -T Advantage : They retain chlorine longer More prolonged bactericidal effects It is acidic from so HOCL remain for longer time

37. Microbicidal activity 5000ppm=10 6 Cl.difficle spore in less than 10 minutes 1000 ppm = M.tb 500 ppm =Candida in 30 seconds 100 ppm = B.atropheaus in lesstthan 5 minutes, 106-107 S.aureus , Salmonella, Proteus, pseudomonas Bleach Dilution Chlorine level in ppm 5.25-6.25% None 52500-61500 (5 liter) 1:10 5250-6150 (4500-500) 1:100 525-615 (4900-100) 1:1000 53-62 (4950-50)

38. Use: Tonometer head, For decontamination of blood spill Disinfection of water supply Legionella contaminated hospital water

39. Iodine And Iodophor Disinfectants Iodine tinctures : 2% iodine + 2.4% sodium iodide (NaI) in 50% ethanol; I t is used as a skin disinfectant , as a nonirritant antiseptic on wounds and abrasions . Strong iodine tincture : C ontains 7% iodine and 5% potassium iodide (KI) dissolved in 95% ethanol . I t is more potent but also more irritating than tincture of iodine.

40. Idophors Combination of iodine and solubilizing agent/ carrier Which causes sustained release of iodine Example: povidone iodine= polyvinylpyrrolidone and Iodine, which is free of toxicity and irritant effects It must be diluted according to manufacturer’s direction MOA: protein and nucleic acid disruption It is bactericidal, tuberculocidal , virucidal but it require prolong contact time Use: disinfection of blood culture bottles, medical equiment -thermometer, endoscope Not use on silicone catheter: due to adverse effects on silicone tubing

41. Skin disinfectant Surgical scrubs

42. Low Level Disinfectant Phenol Quaternary ammonium compounds Alcohol Surfactant Heavy metals

43. Alcohol Ethyl alcohol, Isopropyl alcohol, Methyl alcohol MOA: Denaturation of protein Absolute ethyl alcohol= less batericidal than water+ alcohol because denaturation is quick in presence of water.

44. Microbicidal activity No acitivity when diluted by 50% Methyl alcohol Ethyl alcohol Isopropyl alcohol Weak bactericidal 60-80% = Bactericidal, Virucidal (enveloped/ nonenveloped )f ungicidal (tissue phase> culture phase) 95%= Tuberculocidal All except non enveloped virus

45. Alcohols Alcohols are commonly used topical antiseptics . They can be used as a reasonable substitute for handwashing as long as hands are not visibly soiled. They are also used to disinfect the surface of medical equipment. Alcohols require time to work and they may not penetrate organic material.

46. Alcohols They also evaporate rapidly which makes extended exposure time difficult to achieve unless the items are immersed. Alcohol irritates tissues. They are generally too expensive for general use as a surface disinfectant

47. Not recommonded for sterilizing medical and surgical material due to lack of sporicidal action and they can not penetrate protein rich material Use in disinfection of oral/rectal thermometer, scissers , stethoscopes

48. PHENOLICS Examples : Benzyl-4-chlorophenol, Amyl phenol, Phenyl phenol Advantages and disadvantages : good general purpose disinfectants, not readily inactivated by organic matter, active against wide range of organisms (including mycobacterium), but not sporicidal .

49. Phenol as Disinfectant They are not effective against nonenveloped viruses and spores. These disinfectants maintain their activity in the presence of organic material. This class of compounds is used for decontamination of the hospital environment, including laboratory surfaces, and noncritical medical items

50. Phenol as Disinfectant Phenolics are not recommended for semi critical items because of the lack of validated efficacy data for many of the available formulations and because the residual disinfectant on porous materials may cause tissue irritation even when thoroughly rinsed.

51. Phenol as Disinfectant Phenolics are not recommended for semi critical items because of the lack of validated efficacy data for many of the available formulations and because the residual disinfectant on porous materials may cause tissue irritation even when thoroughly rinsed.

52. Surfactants Decrease surface tension Soaps and detergents Quaternary ammonium compounds : microbicidal

53. Antiseptics Biguanides: Chlorhexidine Low toxicity Used on skin and mucous membranes

54. Although chlorhexidine is effective in the presence of blood, soap, and pus, its activity is reduced

55. Heavy Metals Denature proteins silver nitrate (topical cream) mercuric chloride (paint) copper sulfate (algaecide) zinc (mouthwash, paints)

56. Mercurochrome-antiseptic

57. Zinc+ ferric oxide

58. Antifungal action

59. Uses Of Disinfectant In Hospital

60. Hospital equipments Reprocessing of Endoscope HAI Heat sensitive endoscopes-GI , Bronchoscope, nasopharyngeoscope All must be properly cleaned first . Should minimally subjected to high level disinfectant Most common in use : 2% gluteraldehyde for 20 minutes Other imp: Orthophthaldehyde 0.55% (is now replacing gluteraldehyde due to its less irritant property on eye and nasal mucosa,12 minutes) Other: 7.35% hydrogen peroxide + 0.23% peracitic acid 1 % hydrogen peroxide+ 0.08% peracitic acid 7.5 % hydrogen peroxide But all 3 are more corrosive and causing functional damage on endoscope Automated endoscope reprocessors

61. Cleaning: Important process before using disinfectant Removal of soil and organic material from objects Normally done by water with detergent and enzymatic products Enzymes: proteases: to remove blood and pus Lipase: enzymatic action on fat Amylase: starch It can be done mannually or by ultrasonic cleaners/water -disinfector 2 essential components of manual cleaning Friction-rubbing/scrubbing the soiled area with a brush Fluidics-fluids under pressure, use to remove soil and debris from internal channels after brushing All enzymes =must be rinsed

62. 5 steps in reprocessing Cleaning : Mechanically cleaning of internal and external surfaces by brushing, flushing with water and detergent with /without enzymes Disinfection: Immerse endoscope in high level disinfectant / chemical sterilient & perfuse. Disinfect all accessible channels. Rinse: With sterile /filtered/tap water (that meets federal clean water standard at point of use) Dry: Rinse with alcohol and dry with forced air after disinfectant and before storage Storage : To prevent redecontamination and to promote drying. Hanging vertically in a ventilated cabinets-good method

63. Dental instruments

64. Type of instruments Example Method of disinfection Instruments that penetrates soft tissue and bone Extraction forcep , scalpel blade, bone chisels, periodontal scales, surgical burs Critical items Should be discarded or sterilized only Not penetrating bone and soft tissue Air / water syringe, amalgam condensors Semicritical items Sterilized/ high level disinfectant Clinical contact (Surfaces that might be touched frequently with gloved hands during patient care) Light handles, switches, dental x-ray equipments, chair side equipment Use barrier protective covering, disinfect on each day of use with low or intermediate level disinfectant House keeping surfaces Clean with water, detergent, disinfectant

65. Disinfection of HBV, HCV, HIV, Tb contaminated items High level disinfectant is appropriate (CDC) For HCV : 2% gluteraldehyde for 20 minutes Chlorine compound are ineffcetive

66. In Hemodialysis Units In includes Hemodialysis machines, Water supply, Water treated systems, Distribution system Non –critical surface : Dialysis chair/bed, Countertops, External surface of machine, Equipments Disinfect with EPA registered disinfectant/ hypochlorite solution (500-600 free chlorine) Hemodialyser : 7.2% peracetic acid, 20% formaldehyde,

67. Inactivation Of Cl.difficle Carpeted room> non carpeted room Hypochlorite solution(1600 ppm available chlorine) Contaminated medical devices like colonoscopes & thermometers = 2% gluteraldehyde for 20 minutes or orthophthaldehyde with peracetic acid Hand washing, barrier methods, environmenta cleaning

68. For Occupational exposure Of Blood borne pathogens Disinfectant must be tuberculocidal M/c is hypochlorite solution (1:10 or 1:100 dilution) In presence of large spill: 1:10

69. Emerging pathogens Cryptosporidium: Most disinfectant not effective except 6%-7.5% hydrogen peroxide E.coli O157:H7: Chlorine 1 ppm for 1 minutes H.pylori : Ethanol (80%), Gluteraldehyde (0.5%), Chorhexidine gluconate (0.05-1%), Povidone iodine (0.1%), Sodium hypochlorite (150 ppm ) Rotavirus: 95% Ethanol, 70% Isopropanol , 2 % Gluteraldehyde , 0.35% Peracetic acid, Sodium hypochlorite(800 ppm free chlorine), Phenol based products (14.7% )

70. HPV and noroviruses : Not 100 % inactivation by disinfectant SARS: 70% Ethanol and Povidone iodine for 1 minutes, 2.5% Gluteraldehyde for 5 minutes

71. Bioterrorist agents Susceptibility of these agents to germicide invitro is similar to that of other related pathogen ( B.anthrax = B.athropheus ) Many of them are stable enough in the environment leads to transmission of agents. Data suggest that current disinfection and sterilization practices are appropriate for managing patient care equipment and environment surfaces when potentially contamination with bioterrosrist agents

72. Suceptibility Of Antibiotic Resistant Bacteria To Disinfcetion Both are not related to each other except with few exceptions like: MRSA strains –less susceptible than MSSA starins to chlorhexidine , propamide , quternary ammonium compounds, but are equally susceptible to phenol

73. Air disinfection in patient care areas Disinfection spray fog techniques are unsatisfactory in patient care area. Other methods: Air filteration , UV radiation, Chlorine dioxide

74. OT Disinfection Sterilization 100% is not achivable . It require standard air flow pattern, standard cleaning, disinfection also. Fumigation: Formaldehyde gas is use Prepared by adding 150 gram of KMNO4 to 300 ml of formaline for every 1000 cubic feet of space. Room should be tightly closed and sealed for 12-24 hours. It is carcinogenic Neutralization should be done by 250 ml of 10% amonia / liter of formaline used is placed in centre of room for 3 hours. OT should be ventilated before the entry of any person. Ideally should be done on week ends.

75. Newer agents: Hydrogen peroxide with silver nitrate/ peracetic acid/other compounds Contact hours: 1 hour OT can be used within 1 hour VIKRON : Contain Pottasium peroxymonosulphate , Sodium dodecyl benzenesulphate , sulphanic acid, inorganic buffer. Can be used for managing spill in OT.

76. Surface cleaning/ disinfection Non critical items Divided as Housekeeping and medical equipments surface Housekeeping: Hospital floor, bed site table, furniture, door knobs, handles Only soap and water are ineffective. Disinfectant should be used. Phenolic compounds =94-99.9%

77. Major problem: Bacterial counts are nearly back to its pretreatment level within few hours. Ideally disinfectant should be left for 10 minutes on surface, but such long time is not practical. Multiple scientific paper have demonstrated significant microbial reduction with contact time of 30-60 seconds. Mop water become increasingly dirty during cleaning. Some hospital uses a new mopping technique ‘microfiber material’ to clean the floor. They are densly constructed, polyester/polyamide fibers 1/16 the thickness of a human hair Positively charged , so attract the dust are more absorbant than a conventional cotton-mop.

78. In our hospital OT disinfection Formaldehyde gas Instruments Sterilied by autoclave / ETO/ plasma sterilized supplied by CSSD Patient care before OT Betardine wash At the time-local site cleaning By betardine Endoscope Gluteraldehyde / Automated machine ENT ward instruments Kept in savlon . Then boied in DW for 20 minutes. The dried and reused. OT table, Trolley Cleaning with hypochlorite MICU Diluted savlon is kept in container for health workers to clean the hands inbetween Hemodializer Company provided disinfectant run by machine itself

79. References: Top ten disinfectants to control HAIs. http://www.hospitalmanagement.net/features/featureppcdisinfectantshaiglobaldata. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008. William A. Rutala , Ph.D., M.P.H.1,2, David J. Weber, M.D., M.P.H.1,2, and the Healthcare Infection Control Practices Advisory Committee (HICPAC). CDC-A Guide to Selection and Use of Disinfectants . Shridhar rao - Testing of disinfectant.

80. Thank you