Veterinary Surgical Nursing

1. Veterinary Surgical Nursing PRINCIPLES OF ASEPSIS

2. Asepsis • A-sepsis • To be “withoutinfection” • But not necessarily without presence of all infectious organisms • Doing enough to prevent routine infections

3. Varying degrees of asepsis • Antiseptic • Degree of kill achieved on living biological surfaces • Povidone iodine • Chlorhexidine • Disinfectant • Degree of kill achieved on inanimate surfaces (floors, walls, equipment) • Bleach • Quaternary ammonium compounds • Sterilising agent • Full kill achieved with sterilising agent (if properly used) • Steam heat • Dry heat • Ionising radiation • Ethylene oxide • Glutaraldehyde

4. Introduction • Wounds of all types are prone to contamination and the eventual development of sepsis or infection. • Nowadays, most people expect to survive surgery, however until this century the mortality rate for even simple procedures was high due to wound infections and shock. 

5. Antisepsis • Antisepsis means the killing of micro-organisms within living tissue.  (eg treating a contaminated wound). • In 1865 the surgeon, Lister, introduced the concept of antisepsis by applying  a mild solution of carbolic acid (phenol) to wounds and dressings circumventing, in many cases, the need to amputate limbs because of infection. 

6. 1865 • Joseph Lister • Reduced surgical mortality ratesfrom 50% to 15% • Sprayed carbolic acid around operating theatres and onto wounds

7. Aseptic technique • Aseptic technique means establishing conditions that prevent thecontamination of surgical wounds. As a veterinary nurse you play a crucial role in its implementation and maintenance. • In practice it is not possible to totally eliminate micro-organisms falling into the wound. However, there is a level of contamination which, when exceeded, will lead to infection. This level will vary between animals and is dependant on the competency of their immune system. This may be impaired by factors such as concurrent disease (eg renal failure, drugs, stress and tissue trauma at the site of the wound).

8. Sources of infection • Environment (incl equipment) • Patient • Personnel

9. Environmental Sources • Room and its contents • Atmosphere • Surgical equipment

10. Patient Sources • Skin • Cavities • Alimentary tract • Respiratory tract • Urogenital tract • Patient-sourced infection may be • Direct (via contact) • Indirect (via blood or lymph stream)

11. Personnel Sources • Clothing • Hands, Hair • Exhaled gases

12. ‘Sterile Field’ • Any areas draped • e.g. anything green • But also paper/plastic drapes • Gowns • Also gloves, instruments, swabs, saline • Includes areas vertically above these fields

13. Wound contamination

14. GOLDEN RULESOF ASEPSIS

15. Confinement • Surgical team members remain within sterile area • Movement out of the sterile area may encourage cross contamination • The entry of personnel into operating theatre greatly increases (x100) the number of air borne particles

16. Talking • Talking is kept to a minimum • Talking releases moisture droplets laden with bacteria

17. Movement • Movement in the operating room or by personnel is kept to a minimum • Only necessary personnel should enter the operating room • Movement may cause turbulent airflow and result in cross contamination

18. Areas Over sterile field • Non-scrubbed personnel do not reach anywhere over sterile fields • Dust, lint or other carriers of bacteria may fall on sterile field

19. Face each other • Scrubbed team members face each other and the sterile field at all times • A team members back is not considered sterile even if wearing a wrap-around gown

20. Sterile equipment • Equipment used during surgery must be sterilised • Unsterile instruments may be a source of cross-contamination

21. Handling sterile equipment • Only scrubbed personnel handle sterilised equipment • Risk of cross-contamination

22. Doubtful instrument sterility • If sterility of an item is questioned it is considered contaminated

23. Table height • Sterile tables are only considered sterile at table height • Items hanging over the table edge are considered non-sterile because they are out of the surgeons vision

24. Gowns • Gowns are sterile from mid chest to waist and from gloved hand to 5 cm above the elbow • Back of a gown not considered sterile even if wrap-around

25. Moisture proof drapes • Drapes covering instrument tables and patient should be moisture proof • Moisture carries bacteria from a non-sterile surface to a sterile surface (“strike-through” contamination) – can happen within a minute

26. Packet edges • If a sterile object touches the sealing edge of the pouch that holds it during opening, it is considered contaminated • Sealed edges are not sterile

27. Damaged or wet wrappers • Sterile items within a damaged or wet wrapper are considered contaminated • Contamination by perforation or moisture “strike through”

28. Body posture • Do not fold hands into the axillary region or dangle on sides • Rather clasp hands in front of the body above the waist

29. Seating • If the surgical team begins surgery sitting then they should remain seated until surgery completion • Surgery field only sterile from table height to chest; movement from sitting to standing may bring bacteria onto sterile field

30. Scheduling • Schedule contaminated surgery last • Abscesses • Bite wounds • Dentals

31. More ideal principles • Staff shower before surgery • Scrub suits used • Positive pressure ventilation of theatre • Sterile air flows away from sterile field

32. The End