Small Doses, Big Impact: The Search To Reduce Skin Surgical Site Infections

Original Article: Effect of Microdoses of Incisional Antibiotics on the Rate of Surgical Site Infections in Skin Cancer Surgery: A Randomized Clinical Trial

What are the key takeaways of this article?

Skin cancer is most commonly treated through surgical excision, but surgical site infections (SSIs) pose a severe challenge, impacting patient experience, costs, and surgical outcomes. Despite the significance of SSIs in skin cancer surgery, evidence-based recommendations on antibiotic prophylaxis remain lacking.

This groundbreaking study aims to consider the effects of incision-site injection of microdosed antibiotics on the rate of SSIs in patients undergoing skin cancer surgery. To do so, a prospective, double-blind, parallel-design randomized clinical trial was conducted at a high-volume skin cancer treatment center in New Zealand over a 6-month period. Patients with allergies to both penicillin and clindamycin, recent preoperative systemic antibiotic use, or an inability to return for postoperative wound assessment were excluded. The control group received buffered local anesthetic alone, while two treatment arms received buffered local anesthetic with microdosed flucloxacillin (500 μg/mL) or microdosed clindamycin (500 μg/mL). The primary endpoint was the rate of postoperative SSIs, defined as a standardized postoperative wound infection score (POWI) of 5 or more. Outcomes in patients with at least 1 postoperative assessment were studied in both intention-to-treat and actual treatment received analyses.

Based on the treatment received, the control group had a 5.7% incidence of clinically significant SSIs (22 out of 388 lesions), the flucloxacillin group had a 5.3% incidence (17 out of 323 lesions), and the clindamycin group had the lowest incidence at 2.1% (9 out of 422 lesions). Similar results were observed in the intention-to-treat population. Even after adjusting for baseline differences in lesion ulceration, statistically significant differences in SSI rates persisted. Both treatment groups showed a significant reduction in postoperative systemic antibiotic use compared to the control group, specifically by one-half (flucloxacillin) or one-quarter (clindamycin). The locally infiltrated microdosed flucloxacillin and clindamycin treatments were safe and well tolerated. Notably, clindamycin proved significantly more effective in preventing SSIs than flucloxacillin, possibly due to its broader coverage against commonly cultured bacteria in skin and soft tissue infections.

Based on the compelling findings, the study strongly recommends the routine adoption of incisional microdosed clindamycin for patients undergoing skin cancer surgery. The strategy appears suitable for widespread implementation due to its impressive efficacy and the absence of adverse events. This study confirms the safety and efficacy reported in patients undergoing Mohs surgery and also significantly extends evidence supporting the use of incisional antibiotics in standard excisional skin cancer surgery. Overall, this groundbreaking study establishes evidence-based guidelines for antibiotic prophylaxis in routine excisional skin cancer surgery, paving the way for improved surgical outcomes and reduced SSI rates.

Publication Date: August 4th, 2023

Reference: Goh M, Hollewand C, McBride S, Ryan N, van der Werf B, Mathy JA. Effect of Microdoses of Incisional Antibiotics on the Rate of Surgical Site Infections in Skin Cancer Surgery: A Randomized Clinical Trial. JAMA Surg. 2023;158(7):718–726. doi:10.1001/jamasurg.2023.1201

Summary By: Sascha Azoulay