Comparative antimicrobial efficacy of 4 surgical hand-preparation procedures prior to application of an alcohol-based hand rub in veterinary students.

Objective: To determine the influence of skin preparations before application of an alcohol-based hand rub (ABHR) on bacterial counts before and after elective surgery.

Study Design: Clinical prospective study.

Sample Population: Veterinary students (n = 103) performing ovariohysterectomies on 140 dogs.

Methods: Participants were randomly assigned to 1 initial surgical preparation on the day of surgery: A - hand preparation with medicated solution (4% w/v chlorhexidine bigluconate followed by an ABHR; B - application of a medication solution (benzalkonium chloride 0.1%-1% and polymeric biguanide hydrochloride 0.01%-0.1%) followed by an ABHR; C - nonmedicated pH-neutral soap hand wash followed by ABHR, and D - direct application of an ABHR. Samples were taken by pressing the distal finger tips to an agar plate before the hand preparation, after the hand preparation (n = 3), after ABHR application, and 120 minutes later. Colony-forming units (CFUs) for samples were determined. Total log CFU and CFU log10 reduction were calculated and used for comparison with P < .05.

Results: Two hours after surgery commenced, the participants of groups that performed a hand preparation had lower total CFUs than those that did not perform a hand preparation (P = .001). In particular, the number of CFUs was lower when ABHR was performed after application of pHN compared to direct ABHR (P = .001).

Conclusion: In this population, performing a hand preparation with pHN prior to applying an ABHR had better antimicrobial effect for the duration of surgery than not performing a hand preparation.

Clinical Significance: Surgeons should wash their hands prior to ABHR before starting their first surgery of the day, even when hands appear clean.