In vitro pressure manifolding distribution evaluation of ABThera(™) Active Abdominal Therapy System, V.A.C.(®) Abdominal Dressing System, and Barker's vacuum packing technique conducted under dynamic conditions

Objectives: Temporary abdominal closure methods allow for management of open abdomens where immediate primary closure is not possible and/or where repeat abdominal entries are necessary. We assessed pressure mapping and fluid extraction efficiency of three open abdomen dressing systems: ABThera(™) Active Abdominal Therapy System, V.A.C.(®) Abdominal Dressing System, and Barker's vacuum packing technique.

Methods: An in vitro test model was designed to simulate physical conditions present in an open abdomen. The model consisted of a rigid rest platform with elevated central region and a flexible outer layer with centrally located incision. Constant -125 mmHg negative pressure was applied according to the type of system, under simulated dynamic conditions, using albumin-based solution with a viscosity of 14 cP. Data were collected by pressure sensors located circumferentially into three concentric zones: Zone 1 (closest to negative pressure source), Zone 2 (immediately outside of manifolding material edge), and Zone 3 (area most distal from negative pressure source). Each value was the result of approximately 100 pressure readings/zone/experiment with a total of three experiments for each system.

Results: Pressure distribution of ABThera Therapy was significantly (p < 0.05) superior to Barker's vacuum packing technique in all three evaluated zones. Similarly, V.A.C. Abdominal Dressing System pressure distribution was significantly (p < 0.05) improved compared to Barker's vacuum packing technique in all zones. There were no pressure distribution differences in Zone 1 between ABThera Therapy and V.A.C. Abdominal Dressing System; however, in Zones 2 and 3, ABThera Therapy was significantly (p < 0.05) superior to V.A.C. Abdominal Dressing System.

Conclusions: These data suggest that all approaches to negative pressure therapy for open abdomen treatment are not equal. Additional research should be conducted to elucidate clinical implications of data demonstrated here.