Book 14 · Page 55 / 15

Sterile Against Clean: Two Different Jobs, One Catheter

The sterile field seen from above with the six rules that keep it sterile. — Fig 15.5 · pending clinical review

	Medical asepsis, clean technique	Surgical asepsis, sterile technique
Goal	Reduce the number of organisms and stop their transfer.	Exclude all microorganisms from a defined space.
Hand preparation	Hand hygiene before and after patient contact, and between tasks on the same patient.	Hand hygiene, then sterile gloves donned without touching the outer surface.
Gloves	Clean gloves.	Sterile gloves, changed the moment they are compromised.
Field	Clean work surface, dedicated equipment where possible.	A sterile field established before the first item is opened.
Contamination	Visible soil, or a clean item touching a soiled one.	Any of the four boundary breaks below.
Typical skills	Oral care, bed baths, intermittent enteral feeding, many simple dressing changes where policy allows.	Indwelling urinary catheter insertion, open tracheostomy suctioning, central line site dressing changes, entry into a normally sterile cavity.
The classic error	Wearing the same gloves from a soiled task to a clean one on the same patient.	Reaching across the field, or turning away from it and coming back.

The field boundaries

The outer one inch of the drape edge is not sterile. Anything below waist or table level is not sterile, including a gloved hand that drops. Anything out of the nurse's sight is not sterile, including a field turned away from for a moment. A wet field is a contaminated field, because moisture wicks organisms upward from the surface beneath. Sterile touches only sterile, and an arm crossing over the field contaminates what is under it. Solutions are poured from a bottle held clear above the receptacle so the hand never passes over the sterile surface.

Worked skill · indwelling urinary catheter

Set the field before opening anything. One hand becomes and stays nondominant the moment it separates the labia or holds the penis, and it does not return to the field for any reason. Cleanse in one direction, one swab per stroke, discarding each. Advance until urine returns, then advance further before inflating the balloon with the prefilled sterile water syringe supplied by the manufacturer. Secure the tubing to prevent traction, keep the drainage system closed, and keep the bag below bladder level and off the floor. If sterility is broken at any point, stop and restart with new equipment rather than continue.

Memory hookONE INCH · ONE WAIST · ONE LOOK AWAY.

Margin noteif you looked away, it's dirty.

Watch outinflating the balloon before urine returns can rupture the urethra. Urine first, advance further, then inflate.

TakeawayClean technique reduces organisms, sterile technique excludes them, and the sterile field has four boundaries that never move.

Precaution category and personal protective equipment selection → BOOK 04 · P5.