Chapter 1 Antiseptic and Aseptic Surgery

 

 

 

 1.1 Lecture Outline:

Antiseptic and Aseptic Surgery 

1.1.1 Surgery:

That branch of medical science which deals with therapeusis of a disease or injury with manipulative or operative methods, alone or in combination with other pharmaceutical modalities. 

1.1.2 Antiseptic Surgery:

Surgery performed under the protection of an antiseptic. Lister advocated the use of carbolic acid sprays in surgery to clear the operative field and to saturate the dressings for surgery. 

1.1.3 Antiseptic:

A chemical agent that kills pathogens or inhibits their growth.

1.1.4 Aseptic Surgery:

Also called sterile surgery. It is achieved by a combination of techniques that are designed to maintain areas or objects which come in contact with, the operative wound, as free of micro organisms as possible? 

1.2 Early Concepts of Infection

• - Hippocrates (460 B.C.) foreshadowed asepses when he advocated the use of wine or boiled water for irrigating wound.
• - Galen (131-210 A.D) used boiled instruments to treat-wounded gladiators.
• - Vesalius taught that supparartion was an essential part of healing process.
• - Semmelweis (1818-1865) required hand washing in chlorinated-lime solution.
• - Pasteur (1860) showed the role of Bacteria in fermentation of wine and disease.
• - Koch (1878) advocated the use of bichloride of mercury as an antiseptic.
• - Lister (1865) used carbolic acid spray in operating room and or other materials used in surgery.

Miain sources of pathogens in the operative wound are:

• - Environment of OR/Surgical suites.
• - Personnel in Surgery
• - Patient
• - Equipment

Pathogen load of the operative wound can be reduced by

I. Proper maintenance of OR environment

General recommendations are:

• 1. Strict adherence to dress code
• 2. Proper surgical suite design
• 3. Ingress of only clean/sterile materials into Operating Room
• 4. Pursuance of good housekeeping
  • a. Damp mop with a germicidal solution all flat - surfaces, light fixtures, equipment and floors etc. at least once a day or an hour before surgery 
  • b. Between cases
    • a) bag and seal litter, sponges etc.
    • b) damp dust if needed
    • c) change mops and solution 
  • c. At end of day
    • a) damp mop debris from floor,
    • b) clean used equipment and replace
    • c) wash and sterilize mops and dust cloths.
  • d. Weekly/monthly thoroughly
    • a) wash dust and clean walls, ceiling, wheeled equipment, tables etc;
    • b) replace air filters;
    • c) resterlize instrument packs if more than a month old etc.
• 5. Propagation and practice of aseptic surgical principles and conscience.
  • a) All articles used in an operation are previously sterilized.
  • b) Sterile person touch only sterile surfaces.
  • c) If in doubt about the sterility of anything, consider it nonsterile d) Table are sterile only at table top
  • e) Gowns are considered sterile from waist up in front only.
  • f) Edge of anything that encloses sterile contents is not sterile.
  • g) Sterile persons keep contact with sterile areas to a minimum.
  • h) Moisture may cause contamination
  • i) When bacteria can't be eliminated from a field, they must be kept to a minimum.

II. Preparation of Surgical personnel

a) Attire:

The personnel entering the surgical suites must don a fresh "clean" scrub suit and cap. mask and booties are to be put on before entering the Operating room.

• - The blouse must be tucked inside the trousers.
• - Trousers may be tucked inside the socks or trousers may have ankle gripping cuffs.
• - A naked individual may desquamate 100,000 to 309000,000 particle per minutes

b) Personnel hygiene:

• - Bathe and shower daily
• - Keep nails clipped short and smooth
• - Remove all Jewelry before each session in the surgical area
• - Wash hands using general hand washing procedure before each session, between cases, and at the end of each session.

c) Preparation of sterile personnel

• - Remove Jewelry
• - Change into scrub suit
• - Don head gear
• - Perform surgical scrub with either Hexochlorophene,

Povidone - Iodine, chlorhexidine glucomate.

• - Don a sterile gown
• - Don sterile gloves

III. Preparation of Surgical Patient

• - Verify the patients identity and confirm the preoperative preparation
• - Before anesthesia allow the animals to defecate and urinate.
• - If needed or conditions permit, it is beneficial to bathe and dry the entire animal to remove loose hair, debris, and external parasites promoting a cleaner operation room.
• - Clip a liberal area about 20 cm around the planned incision with a #40 clipper blade
• - Depilatory creams are shown to reduce wound infection rates in people
• - After vacuuming the clipped hair the operative site is given a general cleaning scrub with betadine surgical scrub. The area is leathered well and rinsed so as to remove all oils and dirt.
• - Scrubbing progresses from proposed incision line outwards in a circular fashions
• - Discard the Sponge on reaching the peripheral edge of the clipped area.
• - Transfer the animal to surgical theater and secure to the operating table in a desired position.
• - Paint the surgical site in a circular pattern with a germicidal agent such as Betadine solution, Allow it to dry 3 to 4 minutes to have maximum skin effect.

IV. Preparation of Equipment

• - Equipment sterilization is done outside the Operating Room.

Sterilization in surgery, means complete elimation of microbial viability, including both the vegetative forms as well as spores.

There are two general categories in which various methods of sterilization can be grouped under.

 A Physical sterilization

• - Thermal
• - Filtration
• - Radiation 

B Chemical sterilization

• - germicidal solutions
• - ethylene oxide 

  A Thermal: 

  A Steam sterilization: is the most commonly employed method of sterliation of equipment. There are types of auto claves available. e.g.

  • - pressure steam sterilizer
  • - steam pressure sterilizer
  • - vacuum steam sterilizer
  • - dressing sterilizer
  • - gravity displacement sterilizer
  • - Instrument packs are positioned vertically (on edge) and longitudinally in autoclave
  • - A 13 minutes sterilizing cycle (exposure to saturated stem at 1210c) is a safe minimum required
  • - Large linen packs require 30 minutes at 1210c (250 F)
  • - Once sterilized store sterile packs in closed cabinets. All packs should be dated.

  Radiation:

  Ultraviolet light: For Surface sterilization, Ionizing radiations and Beta and cathode rays used to sterilize heat sensitive prepackaged surgical materials

  Filtration: used in air conditioning system to remove particles as small as 0.3 um in diameter. Also used to filter-sterlize heat labile solutions.

  eg. Surgical mask - to produce 2 fold effect 

  B Chemical agent

  An ideal chemical agent will

  • - kill all pathogenic microorganism
  • - work effectively in short period of time
  • - exert residual action
  • - not corrode, dry or stain
  • -- be stable, odorless, non toxic
  • -- be effective in presence of organic matter
  • -- not be inactivated by other concurrently used chemicals

    a. Agents in solution form

    • Alcohol
    • Aldehyde
    • Oxidizing agent e.g. Halogens
      • - Inorganic Iodine compounds
      • - Organic Iodine compounds
    • Surfactants -- Soaps - detergents,
    • Phenolic derivatives - carbolic acid

    b. Chemical sterilization by gases

    Ethylene oxide: It acts by inactivating the DNA molecules in the microbial cells thus preventing cell reproduction. It takes: Temperature - 120 to 140F (50 to 600 

    c) Conc. - 500 to 1000 mg/l

    • Humidity - 60 to 80%
    • Time - 3 to 6 hours

    Let stand for 24 hours at room air before use. 

    Read Chapter 1 and 2; Small Animal Surgical Nursing Tracey and Warren; CV Mosby and Co; St. Louis, l983