Negative Pressure Wound Therapy (NPWT) at Altitude for Complex Wounds

Introduction: Negative pressure wound therapy (NPWT) for soft tissue injury (STI). Early post-transfers via AE to definitive care may induce bacterial proliferation (BP). However, NPWT/instillation in limiting BP during post-injury AE has not been studied. We hypothesized instillation NPWT during simulated aeromedical evacuation (SAE) would decrease colonization within STI. Methods: For STI, two 4 centimeter (cm) dorsal wounds were created in 34.9 + 0.6 kilogram (kg) porcine and inoculated with Acinetobacter baumanii (AB) or Staphylococcus aureus (SA) 24 hours (h) prior to a 4h SAE or ground control. Randomized models: wet-to-dry (WTD) dressing, NPWT, instillation NPWT-normal saline (NS-NPWT), instillation NPWT-normosol (NM-NPWT), and RX4-NPWT. Complex wound (CW) were inoculated with AB 24h prior to SAE with WTD or RX4-NPWT dressings. Collected samples at baseline, pre-flight, and 72h post-flight. Results: SAE did not affect BP. The STW arm demonstrated a decrease in SA/AB SAE using RX4-NPWT. NS-NPWT during AE effectively prevented BP than WTD dressing. There was no difference in colony forming units (CFU). Conclusion: The environment did not independently affect bacterial growth. RX4-NPWT provided effective bacterial reduction post SAE, followed by NS-NPWT. Future research to determine ideal instillation fluids, pressure settings, and dressing change during AE is recommended.