Inoperable peripheral arterial disease (PAD) and extensive pedal infections act as major barriers to achieving wound healing. Pre-clinical studies demonstrated that antibiotics delivered locally at high continuous levels utilizing percutaneous isolated limb perfusion (PILP) resulted in higher deep tissue antibiotic levels.
To determine safety of the PILP procedure in patients with diabetes-related foot infections and to investigate the effectiveness of recirculating ticarcillin / clavulanic acid (Timentin) on microbiological load.
Five individuals with diabetes, pedal infection and PAD requiring peripheral angiography were recruited. The antegrade femoral artery catheter from the peripheral angiogram, retrograde Venous Recovery Catheter and Venous Support Device were connected to an oxygenator, heater and paediatric cardiac perfusion pump. Circulation of the limb was isolated by external tourniquet. All individuals underwent a single 30 minute PILP treatment episode. Biochemistry, antibiotic levels and microbiology samples were collected during and following the procedure.
No alteration in vital signs or biochemical parameters from the limb or systemic circulation, were recorded during the procedure or 28 day follow-up. There was approximately a 10-fold increase in ticarcillin concentrations in the lower limb circuit as compared to systemically at the end of the procedure. Large reductions in quantitative bacterial levels were observed within 6 hours following the procedure. Subject 1 had too few organisms to quantify post PILP. Subject 2 had a log reduction in colony forming units (CFU) 6 hours post PILP and eradication of 1 of the original 3 bacterial species by day 3. Subject 3 had a log reduction in CFU at 6 hours and 3 days post PILP and eradication of 3 of the 4 original bacteria species. Subject 4 had insufficient tissue. Subject 5 had too few organisms to quantify post PILP.
This first in human study suggests that the recirculation of Timentin via PILP is both safe and achievable. The results demonstrate significant reductions in quantitative bacterial levels within 6 hours of PILP and encourages the need for larger, randomised studies.