Abstract:
A method and system of treating an instrument after contamination of a surface thereof includes the steps of covering the surface with a foam and then subsequently treating the foam with a defoaming agent.

Description:
[0001]     This application is a continuation-in-art of prior U.S. patent application Ser. No. 11/396,186 filed Mar. 31, 2006, the entire contents of which are incorporated herein by reference. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     The present application relates to processing of medical instruments prior to reuse, and more particularly to pretreatment of the instruments with a foam.  
         [0003]     Medical instruments after use are typically contaminated with blood and other body matter as well as potentially contaminated with infectious microorganisms. Before being reused in a future medical procedure these instruments must be washed and sterilized. The process of washing and sterilization becomes complicated when blood and other matter are allowed to dry onto the instruments. Blood in particular becomes much more difficult to remove once it has dried.  
         [0004]     It has been suggested that after use instruments be placed into a liquid filled container to maintain moisture and prevent foreign matter thereon from drying and becoming more difficult to remove. However, such containers can be quite heavy and difficult to move and the liquid therein can become contaminated and it is not desirable to spill this liquid. One solution that has been proposed is an enzymatic foam which is prayed onto instruments after use and prior to eventual sterilization. The foam weighs less than a liquid and purports to enhance cleaning by initiating some degree of cleaning at the early stage when the foam is placed upon the instrument. Such foams provide little or no antimicrobial activity. We have found the hydrogen peroxide foam improves upon enzymatic foams having superior cleaning ability against dried blood and providing a substantial measure of antimicrobial activity to start the decontamination process and to thereby enhance its effectiveness and provide some measure of protection to personal against infection from the instruments when they are removed from the container.  
         [0005]     Regardless of which type of foam is applied to cover the instruments, an instrument, particularly one having sharp edges and potentially contaminated with pathogens presents a danger to a user attempting to remove it from the container while it is covered with foam. If the user can not properly visualize the instrument then the user is at risk of injury from the sharp edges and potentially at risk from pathogens.  
       SUMMARY OF THE INVENTION  
       [0006]     The present invention further enhances protection of the user at the time of instrument removal by reducing the physical volume of the foam.  
         [0007]     A method, according to the present invention, provides for treating a contaminated instrument. The method includes the steps of: placing the contaminated instrument in a container; applying a foam to the contaminated instrument; maintaining the foam on the instrument in the container; and applying a defoamer on the instrument in the container to reduce volume of the foam.  
         [0008]     The foam can comprise a disinfectant, such as hydrogen peroxide. The foam can comprise a cleaning solution, such as a sufactant or an enzymatic cleaner for proteinacious material.  
         [0009]     The defoamer can comprise an organic-based defoamer. Preferably, the defoamer comprises a silicone-based defoamer such as a silicone emulsion. The defoaming agent can comprises a siloxane polymer.  
         [0010]     In one aspect of the invention, the defoamer is applied manually. Preferably it is sprayed over the foam, from a manually operated spray bottle, an aerosol can or other spray dispenser. The defoamer could also be used during an automated cleaning process such as an automated instrument washing and high level disinfection process, such as in an automated endoscope reprocessor, in which case the defoaming agent could be applied automatically. Depending upon the nature of the foam and the automated process, application of the defoamer could be critical to prevent an abundance of foam from interfering with the washing or disinfection process.  
         [0011]     In one aspect of the invention, prior to the application of the defoamer the instrument is sufficiently covered with the foam so as to not be substantially hidden from view of a user and subsequent to the application of the defoamer the instrument is substantially visible to a user whereby a user may safely reach into the container to remove the instrument. The user may then safely remove the instrument from the container. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0012]      FIG. 1  is a block diagram of a system according to the present invention;  
         [0013]      FIG. 2  is a block diagram of an enhanced system of  FIG. 1 ;  
         [0014]      FIG. 3  is a front elevation view of a foam dispenser for use in the system of  FIG. 1 ;  
         [0015]      FIG. 4  is a front elevation view of an alternative foam dispenser for use in the system of  FIG. 1 ;  
         [0016]      FIG. 5  is a front elevation view in cross-section of a container for use in the system of  FIG. 1 ;  
         [0017]      FIG. 6  is a front elevation view in cross-section of an alternative container for use in the system of  FIG. 1 ; and  
         [0018]      FIG. 7  is a front elevation view in cross-section of a further alternative container for use in the system of  FIG. 1 . 
     
    
     DETAILED DESCRIPTION  
       [0019]     During a medical procedure, one or more medical instruments may be employed. These instruments become contaminated with blood, tissue and potentially contaminating microorganisms. Typically the instruments are set aside after use to await washing and sterilization. This waiting period can be several hours or much longer. During this waiting period blood and other matter which dries upon the instrument becomes much more difficult to remove during the subsequent cleaning procedure. This can be a particular problem when a procedure lasts many hours and uses many different instruments or when due to limited personnel time, it is difficult to process the instruments in a timely fashion.  
         [0020]     Turning to the drawings, and in particular to  FIG. 1 , according to the present invention, after use and prior to a complete washing and sterilization procedure the instruments  10  are placed into a container  12  and covered with a foam  14 . The foam comprises hydrogen peroxide. The hydrogen peroxide foam  14  acts to dissolve blood, even dried on blood, and to initiate antimicrobial activity against microorganisms on the instrument. The foam  14  encapsulates the instruments  10  and maintains a moist state thereon to inhibit drying of blood and other matter on the instrument. Keeping the blood and other matter from drying promotes superior washing in a subsequent washing and sterilization process.  
         [0021]     One method of dispensing the hydrogen peroxide foam  14  would be to spray the foam  14  from a foaming aerosol spray can  16 . Such cans employing a propellant are well known to those of skill in the art. Also, the container  12  preferably includes an insert or tray  18  having a plurality of apertures therethrough to allow easy rinsing of the instruments  10  and for efficient diffusion of vapor sterilants into contact with the instruments  10  when the container  12  is used in a sterilization procedure. A lid  20  is also preferably provided.  
         [0022]     Instruments  10  are placed into the container  12  as they are finished being used in a procedure. A quantity of foam  14  is sprayed over the instruments  10  to keep them moist and inhibit drying of blood thereon, to start dissolving the blood thereon and to disinfect the instruments. The foam  14  preferably contains between 1 to 15 percent hydrogen peroxide by weight and more preferably between about 3 to 8 percent. Such concentration may not achieve a level of sterilization sufficient for immediate reuse on a patient, but will substantially reduce the load of microorganisms on the instrument surfaces so as to minimize the chances that personal handling the instruments, especially during cleaning, will get infected from them. The lid  20  is preferably placed on the container  12  prior to transporting the instruments from the location of the procedure, such as an operating room, to the location of the washing. When the instruments  10  are ready for washing, the insert  18  can be lifted out and the foam  14  rinsed off while the instruments  10  are still in the insert  18 . Normal washing and sterilization may then occur. Washing may comprise treatment with enzymatic cleansers, detergents or other cleaning agents, preferably in combination with mechanical scrubbing or agitation, including optionally treatment with water jets, ultrasonic vibration or the like. Following washing the instrument should be sterilized, preferably in the container  12 , such as by chemical vapor or steam autoclaving.  
         [0023]     It is particularly convenient if the container  12  with the insert  18  is adapted for use in the terminal sterilization such as a STERRAD® hydrogen peroxide/gas plasma system or a steam system. Suitable materials, such as liquid crystal polymers, and construction details for such containers, especially containers adaptable to either steam or hydrogen peroxide, are shown in U.S. Pat. Nos. 6,379,631 and 6,692,693 to Wu incorporated herein by reference. Such containers are typically wrapped with CSR wrap or incorporate semi-permeable membrane filters to allow sterilization of instruments therein with vapor sterilants while protecting the against ingress of potentially contaminating microorganisms after sterilization.  
         [0024]     Turning also now to  FIG. 2 , in addition to covering an exterior surface of the instrument  10  with the hydrogen peroxide foam  14 , if the instrument  10  has a lumen  22 , a liquid or mist  24  comprising hydrogen peroxide is preferably sprayed into the lumen  22  prior to placing the instrument  10  into the container  12  and covering the instrument  10  with foam  14 . The mist is also preferably dispensed from a pressurized container  26  employing a propellant as is known in the art.  
         [0025]     Turning also now to  FIG. 3 , to enhance convenience, a dispenser  28  can be provided with a foaming nozzle  30  and misting nozzle  32 . A foamable hydrogen peroxide solution and a propellant are in the dispenser  28  and when distributed through the misting nozzle  32  the solution comes out as a mist  34  appropriate for squirting into a lumen and when dispensed through the foaming nozzle  30  the solution comes out as a foam  36  appropriate for covering exterior surfaces of an instrument.  
         [0026]     Turning also now to  FIG. 4 , rather than employ a propellant, a dispenser  38  having a foamable solution of hydrogen peroxide therein may employ manually operated misting nozzle  40  and foaming nozzle  42 . A particularly useful foaming nozzle  42  is the Airspray F2-L11 available from Airspray NV, Alkamar, The Netherlands.  
         [0027]     Turning also now to  FIG. 5 , a container  44  is illustrated having a mesh insert  46  and lid  48 . A lower portion of the container has a well  50  into which a quantity of foamable hydrogen peroxide solution  52  may be placed. A port  54  and valve  56  connect to the well  50  through an air bubbler or hydrophobic membrane  58 . A supply of compressed air or other gas attached to the port  54  percolates through the bubbler  58  to foam the hydrogen peroxide solution  52  and fill the container  44  with the hydrogen peroxide foam. Preferably, the lid  48  contains a viewing window  60  to view the progress of foam filling the container  44  and one or more vents  62  to allow gases in the container  44  to escape and allow the foam to fill the container  44 . The vent  62  may be a simple opening, or be covered with a semi-permeable membrane or employ a one-way valve.  
         [0028]     Turning also to  FIG. 6 , an alternative container  64  as structured similarly to the container  44  with an insert  66  well  68  with a hydrophobic membrane  70  and a lid  72  with a window  74  rather than a port for compressed air or gas, a port  76  is provided on an upper location of the container  64  and has a valve  78  and an additional hydrophobic membrane  79 . By attaching the port  76  to a source of vacuum and drawing gases out of the container  64 , air will percolate into the container through the hydrophobic membrane  70  providing a foaming action to hydrogen peroxide solution  52  in the well  68 . In either this container  64  or the previous container  44 , if the foam dissipates, it can be refoamed by employing the vacuum or compressed gas as the case may be.  
         [0029]     Turning also now to  FIG. 7 , a container  80  having an insert  82  and lid  84  with a window  86  has a well  88 . An agitator  90  sits within the well  88  and is attached to a motor  92  and power source, such as a battery  94 , which is controlled via a switch  96 . Engaging the agitator  90  foams a hydrogen peroxide solution  52  in the well  88  to fill the container  80 .  
       EXAMPLES  
       [0030]    
       
         
               
             
               
               
             
               
               
             
           
               
                   
               
               
                   
               
               
                 Formulation 1 
               
             
          
           
               
                   
                 Mousse-Like 
               
               
                 Type of foam 
                 Thick Foams 
               
               
                 Application 
                 Spray 
               
               
                 Ingredients 
                 Wt (g) 
               
               
                   
               
             
          
           
               
                 Deionized Water 
                 60.0 
               
               
                 Carbopol Aqua SF-1 
                 3.4 
               
               
                 Polymer 
               
               
                 Tween 80 
                 2.0 
               
               
                 Glycerol 
                 2.0 
               
               
                 NaOH (1.0N) 
                 As needed 
               
               
                 H 2 O 2   
                 As needed 
               
               
                 Preservative(s) 
                 As needed 
               
               
                   
               
             
          
         
       
     
         [0031]    
       
         
               
             
               
               
             
               
               
             
           
               
                   
               
               
                   
               
               
                 Formulation 2 
               
             
          
           
               
                   
                 Mousse-Like 
               
               
                 Type of foam 
                 Thick Foams 
               
               
                 Application 
                 Spray 
               
               
                 Ingredients 
                 Wt (g) 
               
               
                   
               
             
          
           
               
                 Deionized Water 
                 120.0 
               
               
                 Carbopol Aqua SF-1 
                 6.8 
               
               
                 Polymer 
               
               
                 Tween 80 
                 4.0 
               
               
                 Glycerol 
                 1.0 
               
               
                 NaOH (1.0N) 
                 As needed 
               
               
                 H 2 O 2   
                 As needed 
               
               
                 Preservative(s) 
                 As needed 
               
               
                   
               
             
          
         
       
     
         [0032]    
       
         
               
             
               
               
             
               
               
             
           
               
                   
               
               
                   
               
               
                 Formulation 3 
               
             
          
           
               
                 Type of foam 
                 High Foaming 
               
               
                 Application 
                 Aeration/Vacuum/Spray 
               
               
                 Ingredients 
                 Wt (g) 
               
               
                   
               
             
          
           
               
                 Deionized Water 
                 78.0 
               
               
                 Fixate G-100 Polymer 
                 6.0 
               
               
                 Tween 80 
                 1.0 
               
               
                 SilSense Copolyol-1 
                 1.0 
               
               
                 Silicone 
               
               
                 Glycerin 
                 4.0 
               
               
                 H 2 O 2   
                 As needed 
               
               
                 Preservative(s) 
                 As needed 
               
               
                   
               
             
          
         
       
     
         [0033]    
       
         
               
             
               
               
             
               
               
             
           
               
                   
               
               
                   
               
               
                 Formulation 4 
               
             
          
           
               
                 Type of foam 
                 High Foaming 
               
               
                 Application 
                 Aeration/Vacuum/Spray 
               
               
                 Ingredients 
                 Wt (g) 
               
               
                   
               
             
          
           
               
                 Deionized Water 
                 85.0 
               
               
                 SilSense Q-Plus 
                 1.0 
               
               
                 Silicone 
               
               
                 Tween 80 
                 2.0 
               
               
                 Glycerol 
                 3.0 
               
               
                 59% H 2 O 2   
                 5.0 
               
               
                 Preservative(s) 
                 As needed 
               
               
                   
               
             
          
         
       
     
         [0034]    
       
         
               
             
               
               
             
               
               
             
           
               
                   
               
               
                   
               
               
                 Formulation 5 
               
             
          
           
               
                 Type of foam 
                 High Foaming 
               
               
                 Application 
                 Aeration/Vacuum/Spray 
               
               
                 Ingredients 
                 Wt (g) 
               
               
                   
               
             
          
           
               
                 Deionized Water 
                 91.0 
               
               
                 Fixate G-100 Polymer 
                 6.0 
               
               
                 Tween 80 
                 1.0 
               
               
                 SilSense Q-Plus 
                 1.0 
               
               
                 Silicone 
               
               
                 59% H 2 O 2   
                 5.0 
               
               
                 Preservative(s) 
                 As needed 
               
               
                   
               
             
          
         
       
     
         [0035]    
       
         
               
             
               
               
             
               
               
             
           
               
                   
               
               
                   
               
               
                 Formulation 6 (for ˜ 6% peroxide) 
               
             
          
           
               
                 Type of foam 
                 High Foaming 
               
               
                 Application 
                 Aeration/Vacuum/Spray 
               
               
                 Ingredients 
                 Wt (g) 
               
               
                   
               
             
          
           
               
                 Deionized Water 
                 150.0 
               
               
                 Tween 80 
                 8.0 
               
               
                 SilSense Copolyol-1 
                 2.0 
               
               
                 Silicone 
               
               
                 59% H 2 O 2   
                 18.0 
               
               
                   
               
             
          
         
       
     
         [0036]    
       
         
               
             
               
               
             
               
               
             
           
               
                   
               
               
                   
               
               
                 Formulation 7 (for ˜ 3% peroxide) 
               
             
          
           
               
                 Type of foam 
                 High Foaming 
               
               
                 Application 
                 Aeration/Vacuum/Spray 
               
               
                 Ingredients 
                 Wt (g) 
               
               
                   
               
             
          
           
               
                 Deionized Water 
                 150.0 
               
               
                 Tween 80 
                 8.0 
               
               
                 SilSense Copolyol-1 
                 2.0 
               
               
                 Silicone 
               
               
                 59% H 2 O 2   
                 9.0 
               
               
                   
               
             
          
         
       
     
         [0037]    
       
         
               
             
               
               
             
           
               
                   
               
               
                   
               
               
                 Formulation 8 (Defoaming and neutralizing solution) 
               
             
          
           
               
                 De-foaming agent 
                   
               
               
                 (Rug Doctor water- 
               
               
                 based silicone emulsion) 
                 1% 
               
               
                   
               
               
                 Catalase 
                 ˜1000 units/ml 
               
               
                 Water 
                 Remainder 
               
               
                   
               
             
          
         
       
     
         [0038]     Preferably, a defoaming solution such as Formulation 8 is provided in a spray dispenser, either manually pumped or with a propellant gas and is provided with instructions for defoaming a hydrogen peroxide foam  14  which covers instruments  10 . Prior to defoaming the instruments  10  are covered by the hydrogen peroxide foam  14  making it difficult for a user to see the instruments  10  and remove them from the container  12 . If the instruments  10  have sharp points or edges the user might risk injury by reaching into the foam  14  without being able to adequately see the instruments  10 . Preferably, the defoaming solution comprises both a defoaming agent and agent for inactivating the hydrogen peroxide. Thus, upon spraying the defoaming solution over the foam  14  the foam&#39;s volume is reduced so that the instruments can be seen for safe removal and the concentration of hydrogen peroxide in the foam  14  is reduced to minimize any detrimental effects its contact with a user might present.  
         [0039]     The two most common types of defoamers are organic-based defoamers such as polypropylene based polyether dispersions (Sigma antifoam 204) and fatty acid esters (Sigma antifoam O-30), and silicone-based defoamers such as siloxane polymers (Sigma antifoams A, B, C, Y-30, SE-15). Silicone based defoamers are somewhat preferred due to the ease with which they can be cleaned from an instrument  10  compared with organic based defoamers. However, either type may be used. One appropriate defoaming agent is SILSENSE Copolyol-1 silicone which is a polyethylene glycol (organic) and dimethicone (silicone) copolyol. Additional appropriate defoaming agents include: carboxylates (organic based), monoamides (organic based), phosphoric acid esters (organic based), mineral oil blends (organic based), long chain alcohols (organic based), fluorosurfactants (organic based), hydrophobed silicon/hydrophilic oil mixtures (silicone based), Silicas (such as polydimethylsiloxane polymer with silica) (silicone based), diethylene glycol (organic based), polydiethylenemethyl silicones (silicone based).  
         [0040]     For neutralizing hydrogen peroxide in the foam  14  catalase is preferred due to its ease of use, potent action against hydrogen peroxide, ease of removal and low toxicity. Other agents include cobalt salts, idodide salts, titanium salts, ceric salts and permanganate salts.  
                                                                           Formulation 9 (Foaming Mousse (3% H 2 O 2 ))            Ingredient   Amount (g)   Weight %   Function   Material Type                    Deionized Water   120   83.3   Solvent   Aqueous Phase       Carbopol AQUA SF-1   10   6.9   Thickener   Acrylic Polymer       (35%)       Tween 80   4   2.8   Foaming Agent   Surfactant       SilSense Q-Plus   1   0.7   Foam Booster   Modified Silicone       Silicone           Tack Reducer   Liquid       Hydrogen Peroxide   9   6.3   Disinfecting agent   Oxidizer       (59%)           Decontaminating                   agent       Sodium Hydroxide   As needed   &lt;1.0   pH Modifier   Basic solution       (0.1N)       Citric Acid (50%)   As needed   &lt;1.0   pH Modifier   Acidic solution                 Final pH = 6.1             
 
         [0041]     Modified Formulation 7 (with pH Adjustor)  
                                                                           Modified formulation 7 (with pH adjustor)       High-Foaming (3% H 2 O 2 )            Ingredient   Amount (g)   Weight %   Function   Material Type                    Deionized Water   150   88.8   Solvent   Aqueous Phase       Tween 80   8   4.7   Foaming Agent   Surfactant       SilSense Copolyol-1   2   1.2   Foam Booster   Modified Silicone       Silicone           Tack Reducer   Liquid       Hydrogen Peroxide   9   5.3   Disinfecting agent   Oxidizer       (59%)           Decontaminating                   agent       Sodium Hydroxide   As needed   &lt;1.0   pH Modifier   Basic solution       (0.1N)       Citric Acid (50%)   As needed   &lt;1.0   pH Modifier   Acidic solution                 Final pH = 6.0             
 
         [0042]     Modified Formulation 6 (with pH Adjustor)  
                                                                           Hi-Foaming (6% H 2 O 2 )            Ingredient   Amount (g)   Weight %   Function   Material Type                    Deionized Water   150   84.3   Solvent   Aqueous Phase       Tween 80   8   4.5   Foaming Agent   Surfactant       SilSense Copolyol-1   2   1.1   Foam Booster   Modified Silicone       Silicone           Tack Reducer   Liquid       Hydrogen Peroxide   18   10.1   Disinfecting agent   Oxidizer       (59%)           Decontaminating                   agent       Sodium Hydroxide   As needed   &lt;1.0   pH Modifier   Basic solution       (0.1N)       Citric Acid (50%)   As needed   &lt;1.0   pH Modifier   Acidic solution                 Final pH = 5.6             
 
         [0043]     Preferred Formulation  
                                                   More   Most           Preferred   preferred   Preferred                   Hydrogen   0.1-15%     2-10%     3-8%       peroxide       Surfactant   0.5-20%     1-10%     2-6%       Foam booster   0.1-10%   0.3-5%   0.5-3%       (Modified       silicone)       Thickening   0.5-20%    1-10%   1.5-5%       agent       (Acrylic       polymer)       pH   4.5-7.5   5-7   5.5-6.5                  
 
         [0044]     Tests  
         [0045]     (A) Test with Fresh Blood  
         [0046]     A drop of fresh blood, approximately four millimeters in diameter was applied to a Petri dish. One was left untreated and the other treated with a peroxide foam of formulation 7 generated with Airspray F2-L11 Finger Pump Foamer. Within ten minutes the untreated blood had dried whereas the treated blood had reacted and dissolved in the peroxide foam.  
         [0047]     (B) Tests with Dried Blood  
         [0048]     A drop of dried blood was treated with room temperature tap water for ten minutes and another drop of dried blood was treated with a 3% hydrogen peroxide foam of formulation 7 generated with Airspray F2-L11 Finger Pump Foamer. The drop of dried blood treated with tap water remained after ten minutes. After ten minutes, the drop of dried blood treated with the hydrogen peroxide foam had dissolved.  
         [0049]     An additional test was conducted comparing a commercially available enzyme foam, Prepzyme XF enzyme foam, available from Ruhof Corporation of Mineola, N.Y. A drop of dried blood was treated with the Prepzyme XF and another drop of dried blood was treated with a 6% hydrogen peroxide foam of formulation 6. After ten minutes the blood treated with the Prepzyme XF remained whereas the blood treated with the hydrogen peroxide foam was dissolved within five minutes.  
         [0050]     (C) Foam Stability Test  
         [0051]     A foam prepared according to formulation 9 was placed into a Petri dish of dimensions 150 mm diameter and 15 mm deep. Prepzyme XF was placed into a similar Petri dish. The foams were allowed to rest for one hour whereupon they were inspected. The foam of formulation 9 maintained substantially all of its volume over the period of one hour. The Prepzyme foam had fallen to the extent that a portion of the lower surface of the Petri dish was no longer covered by foam. After four hours the foam of formulation 9 still covered the bottom surface of the Petri dish.  
         [0052]     (D) Tests Against Microorganisms  
         [0053]     Tests of efficacy in killing microorganisms were conducted comparing both a 3% hydrogen peroxide foam prepared according to formulation 7 and 6% hydrogen peroxide foam prepared according to formulation 6 against the Prepzyme XF enzymatic foam using the following test procedure: 
        Step 1: Place microorganism suspension onto sterile filter     Step 2:Allow the suspension to dry     Step 3: Add either peroxide foam or enzyme foam to cover filter     Step 4: Allow foam to set on microorganism for pre-determined time     Step 5: Rinse filter with 10 mL sterile neutralizing/defoaming solution (formulation 8)     Step 6: Rinse filter with three times of 100 mL sterile water     Step 7: Place filter on TSA agar and incubate @32 C for 48 hours     Step 8: Determine the number of survivors (TNTC=Too Numerous to Count)        
 
         [0062]     Efficacy Results with Duplicated Samples:  
                                             Staphylococcus       Pseudomonas               Aureus       aeruginosa                     Control   TNTC &amp; TNTC   TNTC &amp; TNTC           (Average:   (Average:           1.64 × 10 5 )   2.49 × 10 5 )                  
 
         [0063]    
       
         
               
               
               
               
             
           
               
                   
               
               
                   
               
               
                 Exposure 
                   
                   
                   
               
               
                 Time 
                   
                 
                   Staphylococcus 
                 
                 
                   Pseudomonas 
                 
               
               
                 (Minutes) 
                 Foam 
                 
                   aureus 
                 
                 
                   aeruginosa 
                 
               
               
                   
               
             
             
               
                 5 
                 No foam 
                 TNTC &amp; TNTC 
                 TNTC &amp; TNTC 
               
               
                   
                 with 
               
               
                   
                 catalase/de- 
               
               
                   
                 foaming 
               
               
                   
                 agent 
               
               
                   
                 (Control) 
               
               
                   
                 Enzyme foam 
                 TNTC &amp; TNTC 
                 TNTC &amp; TNTC 
               
               
                   
                 (Ruhof 
               
               
                   
                 Prepzyme XF) 
               
               
                   
                 3% hydrogen 
                 TNTC &amp; TNTC 
                 16 &amp; 37 
               
               
                   
                 peroxide 
               
               
                   
                 foam 
               
               
                   
                 6% hydrogen 
                 ˜500 &amp; ˜500 
                 0 &amp; 0 
               
               
                   
                 peroxide 
               
               
                   
                 foam 
               
               
                 10 
                 Enzyme foam 
                 TNTC &amp; TNTC 
                 TNTC &amp; TNTC 
               
               
                   
                 (Ruhof 
               
               
                   
                 Prepzyme XF) 
                 ˜1000 &amp; ˜1000 
                 0 &amp; 1 
               
               
                   
                 3% hydrogen 
               
               
                   
                 peroxide 
               
               
                   
                 foam 
               
               
                   
                 6% hydrogen 
                 46 &amp; 22 
                 0 &amp; 0 
               
               
                   
                 peroxide 
               
               
                   
                 foam 
               
               
                   
               
             
          
         
       
     
         [0064]     In practice, instruments  10  are placed into the container  12  as they are finished being used during a medical procedure. A small amount of hydrogen peroxide foam  14  can be added over each instrument  10  as it is placed in the container  12  if there will be lengths of time in between placing instruments therein. A user may wait until all instruments  10  are in the container to apply the foam  14  and cover the instruments  10  therewith and then place the cover on the container. The foam  14  is light allowing easy transport of the container  12  with instruments  10  and foam  14  therein from the site of the procedure to the site where terminal decontamination and sterilization will occur.  
         [0065]     When a user is ready to process the instruments the cover is removed and the defoaming solution is sprayed onto the foam  14  covering the instruments  10 . The defoaming agent in the solution breaks down the physical structure of the foam  14  and the deactivating agent breaks down the hydrogen peroxide, preferably into water and oxygen. If desired, they may be rinsed in the container with fresh water or other solvent. The user then processes the instruments in their usual manner.  
         [0066]     The invention has been described with reference to the preferred embodiments. Obviously, modifications and alterations will occur to others upon reading and understanding the preceding detailed description. It is intended that the invention be construed as including all such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.