Utilizing Negative Pressure Wound Therapy With Instillation and Dwell Time to Achieve Source Control of Complex Polymicrobial Necrotizing Aeromonas hydrophila Infection Following a Traumatic Amputation: A Case Report

Introduction. Aquatic propeller injuries can pose significant complications in the care of a patient including gross contamination, delayed onset of ischemia, and exposure to unusual water-associated organisms. This case study highlights a circumstance where source control was achieved in a patient that suffered from a polymicrobial necrotizing Aeromonas hydrophila infection following a traumatic aquatic amputation. Case Report. A 26-year-old female sustained a propeller injury in a lake with brackish water that resulted in multiple significant linear lacerations and avulsions as well as a Gustilo IIIB fracture. Due to the extent of injuries, the limb was deemed unsalvageable. Serial washouts began early in the hospital course, but the patient did not hemodynamically tolerate debridement well. Tissue cultures showed a polymicrobial A hydrophila infection. Achievement of source control was attempted through use of negative pressure wound therapy with instillation and dwell time (NPWTi-d) (instillation of 100 mL of 0.125% Dakin's solution, dwell time of 5 minutes, and 2-hour intervals of NPWTi-d at -125 mm Hg) in conjunction with traditional intravenous antibiotics; when this therapy was initiated, the wound measured 51.0 cm x 38 cm x 4 cm with 6.0 cm undermining along the superior border. Within 2 days of NPWTi-d initiation, lab values normalized, and the patient began to clinically improve. By day 17, the NPWTi-d settings were switched to instillation of 80 mL normal saline with a dwell time of 5 minutes and interval 2 hours of NPWT at -125 mm Hg. At day 25, the wound measured approximately 25.0 cm x 30.0 cm. The NPWTi-d was continued throughout hospitalization until grafting was able to be performed; on hospital day 51, nearly 100% take of split-thickness grafting was noted with no residual tissue loss. At 167 days after the initial injury, the patient took her first steps on the prosthetic limb. Conclusions. Negative pressure wound therapy with instillation and dwell time gives clinicians the option to achieve source control in complex wounds with active, myonecrotic, polymicrobial infections through use of bactericidal solution instillation.