The Efficacy of Polyhexamethylene Biguanide (PHMB) with Negative Pressure Wound Therapy in Open Diabetic Foot Amputation

Category: Diabetes; Midfoot/Forefoot Introduction/Purpose: The therapeutic efficacy of negative pressure wound therapy (NPWT) in treating skin defects in diabetic foot ulcers has been demonstrated, although the management of bacterial biofilms remains controversial. Limited clinical data exist on outcomes when utilizing polyhexamethylene biguanide (PHMB) alongside NPWT. This study aims to assess the efficacy of PHMB in diabetic foot ulcers compared to conventional methods during NPWT. Methods: After receiving IRB approval from a single center Korean institution, sixty patients with Wagner 3 or 4 diabetic foot ulcers undergoing open amputation of forefoot and midfoot were included from March 2020 to August 2021. NPWT was administered at two-day intervals post-amputation by an expert surgeon affiliated with the institution. Patients were assigned to 3 different adjuvant therapies; 1) Saline; 2) povidone iodine; and 3) hydrochloric PHMB irrigation solutions. Bacterial cultures were performed, assessing time to negative bacterial culture. Wound analysis utilized a three-dimensional infrared camera (inSight ® , eKare, Fairfax, VA, United States) to measure volume and area continuously and its correlation of risk factors. Results: Patients with hydrochloric PHMB therapy exhibited faster wound recovery rates in terms of volume and area compared to those treated with saline and povidone iodine solutions (p=0.001) (Figure 4 and 5). Hydrochloric PHMB and povidone iodine groups showed significantly shorter times to bacterial negativity compared to the saline group (p=0.001) (Figure 6). HbA1c, body mass index, dialysis status, age, smoking history, and diabetes duration did not significantly impact wound recovery rates. Conclusion: Hydrochloric PHMB with NPWT can be useful to treat open diabetic foot ulcers, with a high wound recovery rate and moderate antimicrobial efficacy, as the combination decreases wound toxicity and intermediate bactericidal effects in comparison to normal saline and povidone-iodine solutions.