During preoperative skin antisepsis, which practice ensures proper antisepsis?

• A. Shave the area immediately before applying the antiseptic
• B. Apply the antiseptic in concentric circles moving from the outer perimeter toward the incision site
• C. Clean the area to be prepped with 70% isopropyl alcohol before applying the antiseptic
• D. Allow the antiseptic solution to dry for the full time recommended in the manufacturer's instructions for use before the surgical drapes are applied

Answer: (D)

The key idea is that antisepsis on the skin must be allowed to work for its full contact time. Letting the antiseptic dry completely before applying surgical drapes ensures the active agent remains on the skin, reaches its maximum antimicrobial effect, and isn’t wiped away or diluted by subsequent steps. Drying time also helps prevent pooling, reduces the chance of chemical irritation, and minimizes the risk that drapes could remove or dilute the antiseptic.

Shaving the area right before surgery can cause microabrasions that harbor bacteria and increase infection risk, so this timing is discouraged. Applying antiseptic in a manner that channels contaminants toward the incision—such as moving from the outer perimeter inward—can carry bacteria into the wound, which defeats the purpose of prepping. And cleansing with isopropyl alcohol before applying the antiseptic may not provide the same sustained antimicrobial effect as the chosen antiseptic agent, and it can be redundant or counterproductive if it’s not part of the recommended cleansing sequence.