← Chapter 4
Health Assessment · Chapter 4

The Asepsis Bench

Surgical asepsis has rules that do not bend: only sterile touches sterile, the outer inch is not sterile, nothing below the waist or out of sight, and doubt equals contamination. Rule on ten moments at a sterile field, build the four device bundles without the traps, and decide what may leave your hands and what never does.
Clean technique or sterile technique?
When you are unsure which applies, ask whether you are crossing into a sterile space. If yes, sterile technique.
Ten moments at the field
You are setting up for a sterile dressing change on a fresh surgical wound. For each moment, decide whether the field is still sterile or contaminated.
The field, as you left it
A sterile drape with a one-inch contaminated border around the outside and a sterile centre zone table surface — not sterile outer 1 inch (2.5 cm) — NOT sterile sterile field in view · above waist · dry
Start with clean versus sterile, then rule on the ten moments.
Answer all ten and press Check my calls.
The rules, in the order they get broken. Only sterile touches sterile. The outer 1 inch (2.5 cm) is not sterile, so place items toward the centre. Keep the field in view and above waist level — never turn your back, and anything below waist or table level is contaminated, including your own hands when they drop. Do not reach across the field; add items from the side, holding the package 6 inches above and dropping the contents onto the centre. Moisture contaminates — a wet drape wicks organisms from the surface underneath, so replace a soaked field. Open the drape’s farthest flap first, then the two sides, then the nearest flap last. Pour with the label against your palm, discard the first small amount over a sink to cleanse the lip, then pour from 4 to 6 inches above the receptacle. Never leave a field unattended — set up immediately before use. And inspect the package first: expiration date, sterilization indicator, seal integrity; torn, wet, punctured or previously opened means discard.
The honest reflex. The moment you think “that might have touched the bed rail,” it did. Contamination in sterile technique is judged by doubt, not by proof. If a glove tears, or you touch anything unsterile, stop, remove and start with a new pair. The cost of a new catheter kit is measured in dollars; the cost of a catheter-associated bloodstream or urinary tract infection is measured in extra hospital days, additional antibiotics and sometimes a life. Nobody has ever been disciplined for re-gloving.
Cleaning, disinfection, sterilization — not synonyms. Cleaning physically removes soil and organic material and must precede everything else, because disinfectants do not work through blood and faeces. Disinfection destroys most pathogens on inanimate objects; high-level disinfection is for semi-critical items that touch mucous membranes, such as endoscopes. Sterilization destroys all microorganisms including spores and is required for critical items entering sterile tissue or the vascular system. The contact time on a disinfectant wipe is not a suggestion — if the surface dries before the stated wet time, wipe again.