Which antiseptic agent is preferred for most surgical skin preparations?

Chlorhexidine gluconate with isopropyl alcohol (ChloraPrep). CHG with isopropyl alcohol (ChloraPrep) is the preferred surgical prep agent for most procedures. It provides the broadest antimicrobial spectrum, fastest onset of action, and longest residual antimicrobial activity. The key limitation is that it must NOT be used near the eyes, ears, or mucous membranes.

During a surgical prep, the scrub sponge should move in which pattern?

From the incision site outward in expanding circles. The surgical prep is performed from clean to dirty — starting at the incision site (the cleanest area) and moving outward in expanding circles toward the periphery. The sponge never returns to a previously prepped area. This technique moves bacteria away from the operative site.

A patient is scheduled for eye surgery. Which antiseptic should be used for the surgical prep?

Povidone-iodine (Betadine). Povidone-iodine (Betadine) is the appropriate antiseptic for eye surgery. Chlorhexidine gluconate (CHG) is contraindicated near the eyes because it can cause corneal damage. Alcohol-based preparations are also contraindicated near the eyes due to irritation and fire risk with electrocautery.

If a sterile drape is placed too low and partially covers the incision site, the surgical technologist should:

Leave the drape and cover it with another drape placed correctly. Drapes should never be repositioned toward the incision site once placed, as this would drag bacteria from a less clean area toward the surgical site. The incorrect drape should be covered with an additional drape placed correctly. Moving a drape in any direction after placement risks contaminating the sterile field.

Key Takeaways

The surgical prep removes transient microorganisms and reduces resident flora on the patient's skin
Common antiseptic agents include chlorhexidine gluconate (CHG), povidone-iodine (Betadine), and isopropyl alcohol
CHG-alcohol combination is preferred for most surgical preps due to superior antimicrobial activity
The prep is performed in a circular motion from the incision site outward (clean to dirty)
The prepped sponge should never return to an area already cleaned (unidirectional)
A contaminated area (e.g., stoma, wound) is prepped LAST with a separate sponge
Draping creates a sterile field around the operative site using sterile towels and drape sheets
Drapes are placed from the operative site outward and should not be repositioned once placed

Surgical Skin Prep & Draping

The surgical skin preparation and draping are critical steps in preventing surgical site infections (SSIs). The surgical technologist may assist with or perform the prep under the direction of the circulating nurse or surgeon.

Antiseptic Agents for Surgical Prep

Agent	Trade Name	Properties	Considerations
Chlorhexidine gluconate (CHG)	Hibiclens	Broad-spectrum, residual activity, not inactivated by blood	Do NOT use near eyes, ears, or mucous membranes
CHG + Isopropyl alcohol	ChloraPrep	Superior antimicrobial activity, rapid onset	Flammable — must dry completely before draping
Povidone-iodine	Betadine	Broad-spectrum, safe for mucous membranes	Inactivated by blood and organic matter; check iodine allergy
Iodine + alcohol	DuraPrep	Rapid onset, residual activity	Flammable; not for mucous membranes
Isopropyl alcohol (70%)	—	Rapid bactericidal action	Flammable; no residual activity

Current Evidence: The CHG-alcohol combination (ChloraPrep) is preferred for most surgical preps because it has the broadest antimicrobial spectrum, the fastest onset, and the longest residual activity. However, it is contraindicated near the eyes, ears, and mucous membranes, where povidone-iodine should be used instead.

Surgical Prep Technique

Principles

Clean to dirty: Begin at the incision site and work outward in expanding circles
Never return the sponge to a previously prepped area — discard and use a new sponge
Prep contaminated areas last: If a stoma, open wound, or drain is present, prep it with a separate sponge after the clean area
Allow to dry completely: Especially important for alcohol-based preps (fire risk)
Extend the prep beyond the anticipated drape field to allow for incision extension if needed

Special Prep Considerations

Situation	Modification
Traumatic open wound	Prep around the wound, then prep the wound last
Stoma present	Cover stoma, prep surrounding skin, then prep stoma with separate supplies
Eye surgery	Use povidone-iodine (Betadine) only — NO chlorhexidine or alcohol near eyes
Ear surgery	Avoid CHG — ototoxic if it enters the middle ear
Skin graft donor site	Prep donor site first (cleaner), then recipient site
Extremity prep	Limb is elevated and held by assistant; prep circumferentially

Draping Principles

Sterile draping creates the sterile field around the operative site:

Drapes are applied from the operative site outward (closest to incision first, then periphery)
Never reach across an unsterile area to place a drape
Drapes should not be repositioned once placed — if a drape is placed incorrectly, it may be covered with another drape but not moved toward the incision
Towel clips secure drapes; penetrating towel clips that pierce the skin are considered contaminated once removed
Fenestrated drapes (drapes with a window/opening) are placed so the window aligns with the incision site
All team members should cuff the drapes over their gloved hands while placing them to prevent contamination

CST Certified Surgical Technologist Exam

1Introduction: CST Exam Overview

2Chapter 1: Perioperative Care — Preoperative Preparation

3Chapter 2: Perioperative Care — Intraoperative Procedures

4Chapter 3: Postoperative Procedures & Ancillary Duties

5Chapter 4: Basic Science

6Chapter 5: Exam Strategy & Practice