Asepsis and antisepsis, disinfectans and sterilization

The major theatre Although aseptic surgery has been done in a tent, under a tree, or on a kitchen table, it is safer if it is done in a room which has been designed to preserve the sterility of the surgical field, to make surgical routines easier, and to prevent mistakes.

Asepsis The most serious sources of infection in a theatre are bacteria from: The pus and extcreta left behind by previous patient The clothes, hands, skin, mounths of the staff The patient himself

Minimize the risk of infection by: Keeping the theatre as clean as possible, so that the pus and excreta of previous patients are removed Making sure that the autoclaving is done conscientiously

Minimize the risk of infection by: Following the rules about the indications for operating, the timing of operations, wound closure, and careful tissue handling Creating and maintaining the sterile zone

Sterile zone

The sterile zone Has to be created anew for each patient in a theatre in which the risk of infection has been reducted as much as possible Its creation starts when a nurse swabs the top of troley with antiseptic, puts two sterile towels on it and lays out sterile gowns and gloves

The sterile zone The operations site joins the sterile zone as it is prepared with an antiseptic solution and draped Nothing which is contaminated must touch anything in this zone until the end of the operation

The sterile zone If the technique of the team is poor, the sterile zone becomes smaller and smaller as he operation proceeds.

Operative team Should be as small as possible . It consist: Yourself the surgeon Your assistant, when you need one The scrub nurse responsible for the instruments The circulating nurse to fletch and carrry The anaesthetist His assistant, if he has one

Two other people are important The theatre charge nurse responsible for organizing the theatre Theatre dresser , who is less educated, but unlike the nurses who come and go, has spent his whole career in the theatre, and so knows its routines and where things are

Aseptic technique Entering the theatre: Anyone entering the theatre must change, in the changing room, into clogs or sandals and into a suit. Decide which operations nedd gowns, gloves or masks.

Aseptic technique Scrubbing up: Adjust the elbow taps to deliver water at a comfortable temperature Wet your hands, apply a little soap or forearms to 5cm above your elbows for one complete minute Wash your forearms

Aseptic technique Scrubbing up: Then take a sterile brush and put soap on it Scrub the lateral side of your left thumb, then its medial side, then the lateral and medial aspects of each succeive finger Scrub your nails, and then the back and front of your left hand Do the same with your right hand Scrub for 5 minutes in all

Aseptic technique Scrubbing up: Rinse the suds from your hands while holding them higher than your elbows Turn off the taps with your elbow Dry your hands with a sterile towel before you put on a sterile gown Dry your hand first, then your forearms

Aseptic technique Scrubbing up: Grasp the folded towel with the fingers of both hands, then step clear, so that you don´t touch anything with the open towel Blot your hands on one corner, then dry your forearms Try not to bring a wet (unsterile) part of the towel back to a dry area

Aseptic technique Gowning: Hold the gown away from your body, high enough to be wel above floor Allow it to drop open, put your arms into the arm holes while keeping your arms extended Then flex your elbows and abduct your arms

Aseptic technique Gowning: Wait for circulating nurse to help you She will grasp the inner sides of the gown at each shoulder and pull them over your shoulders

Aseptic technique Gloving: Dust your hands with powder and rub them together to spread it Be careful to touch only the inner surface on the gloves Grasp the palmar aspect of the turned down cuff of a glove and pull it on to your opposite hand Leave its cuff for the moment

Aseptic technique Gloving: Put the fingers of your already gloved hand under the inverted cuff of the other glove, and pull it on to your bare hand It is a good routine to wash your gloved hands sterile water to remove powder Now help the next person who has gowned on with their gloves

Trauma

The operation site Shaving: The operation site should be socially clean before the operation, and you may have to check this There is usually no need to shave a patient If you shave him, do so on the morning of the operation, or as part of the operation

The operation site Shaving: If you shave him a day or two before , minute abrasions in his skin will become infected and the risk of wound infection will increase If hair is going to get in the way, all you need to do is to clip it short immediately before the operation

The operation site Preparation: Do this as soon as the patient is anaesthetized Start with a soapy solution, and follow this with spirit, or better if there is a low sensitivity to iodine in the community , usealcoholic iodine Take a sterile swab on a hoder, start in the middle of the opertion site, and work outwards

The operation site Preparation: Discard both swab and holder, and repeat the proces with the second swab The spirit will evaporate to leave the skin dry Some surgeon consider thie over-elaborate, and merely use a single application of iodine

The operation site Preparation: Be sure to prepare a wide enough area of skin In an abdominal, operation this should extend from the patient´s nipple line to below his groin

The operation site Draping: Wait until he is anaesthetized Place the first towel across the lowe end of the operation site Palce another across its nearer edge Apply a towel clip at their intersection Place another towel across the opposite edge of the site, and finally one across its upper edge

The operation site Draping: Clip them at their intersections If necessary, grip his skin with the clips, or secure the towels with a stitch Alternatively , drape him with two longutidunal towels clipped at each end, with a towel above and below

The operation site Draping: Then, in an abdominal operation cover his whole abdomen with an abdominal sheet with a narrow quadrangular hole in it If important areas near the surgeon become contaminated, cover them with fresch sterile towels

The operation site Swabs and packs: Use 10 cm gauze squares on spongeholding forceps (swabs on sticks) You wil also need abdominal packs

The operation site Cleaning the theatre: Clean it thoroughly after each day´s list, and completely every week Cleaning instruments: Use an old nail brush Open hinged instruments fully, scrub them, and take special care to clean their jaws and serrations

Boiling and autoclaving Sterilization is the total desctruction of all forms of life, including bacterial spores It is best done with heat, either dry heat in an oven, or steam under pressure in an autoclave Processes (usually chemical) which do not destroy spores are termed „disinfection“

Boiling and autoclaving The basis of aseptic surgery is to kill all micro-organisms on all instruments and dressings, preferably by exposure to steam under pressure If this is impractical, imerssion in boiling water for 10 minutes at sea level will kill all viruses and all vegetative bacteria, but not spores, particularly those of tetanus and gas gangrene

Autoclaves The sterilize is effectively, if there is killing all spores Autoclaves : simple walled autoclaves double walled autoclaves

Autoclaves

Autoclaves

Disinfectants and antiseptics Although heat is the best way of killing micro-organisms, you will have to use chemicals to kill them on a patient´s skin, or on anything which heat might harm, such as drains or some suture materials.

Antiseptics and disinfectants Skin: Any alcoholis solution will do Alcoholic iodine is best: Use it routinally, except in children, on the scrotum, and in allergic patients 0,5% chlorhexidine in spirit is a less satisfactory alternative Apply it to skin after removing all traces of soap

Antiseptics and disinfectants Wounds: There is no substitude for scrubbing brush, plenty of water from a jug, and a thorough surgical toiler Chlorhexidine is useful for cleaning the skin round a wound

Antiseptics and disinfectants Instruments , suture materials and drains: The following agent are effective against HIV and HBV in addition to the classical pathogens 2% alkaline buffered glutaraldehyde is the best 5% fromlain in 70% spirit 0,5% solution of chlorhexidine in 70% spirit with 0,5% sodium nitrite Plain 70% spirit

Antiseptic and disinfectants 10 minutes is the absolute minimum time in these soutions, 24 hours is safer Ideally nothing should be considered sterilized until it has been immersed for 24 hours Wash all equipment well before using it

Antiseptic surgery This used to be standard practice before aseptic methods made it obsolete Aim to sterilize everything coming into contact with the wound by soaking it for a sufficien time in an antiseptic solution

Antiseptic surgery Antiseptic solutions: Use chlorhexidine 5% concentrate to make two solutions: A weak solution of 1/2000 of the active agent in water, use this for soakng towels Make up small quantities of solutions frequently, make them up hot, and clean out the containers well between batches

Antiseptic surgery Sterilizing equipment and drapes: Soak everithing which will come into contact with the wound in one of these solutions for at least 30minutes. Soak sutures and gloves in the solutions Use monofilament for ligatures and sutures, and the minimum number of simple instruments.

Antiseptic surgery Sterilizing equipment and drapes: The most appropriate drape, for a tubal ligation, for example , may be a single solution soaked plastic sheet long enough, and widw enough, to cover the whole patient, with a hole in the middle through which to operate.

Antiseptic surgery Perioperative antibiotics: For rutine use in antiseptic surgery Some operators have given their patients antibiotics prophylactically

Antiseptic surgery While operating: Treat the patient´s skin with the solution for at least five minutes before the operation Wash your hands as usual and put on the wet gloves If you are not using gloves, soak your hands in solutions for five minutes

Antiseptic surgery After operating: Rinse everything free of blood Rinse the instruments, and put them away If possible carry nothing over to the next operation

Thank you for your attention!