Impact of continuous Topical Oxygen Therapy on fluid handling

Introduction: Moisture balance of the wound bed is important in wound healing.1  To maintain this balance it is important that excess exudate is absorbed away from the wound unimpeded into an appropriate absorptive dressing. A dynamic fluid handling test system was used to assess fluid transfer from a simulated wound bed through the open structure of the Oxygen Delivery System (ODS) of the continuous topical oxygen therapy (cTOT) device into an absorbent secondary dressing.Methods:A system replicating clinical use of the cTOT device was utilized, this consisted of the ODS placed on the test platform (wound bed) and covered with an absorbent dressing. The cTOT system was connected to the oxygen generator (OG) and oxygen flowed into the ODS. The dynamic fluid transfer of simulated exudate through the ODS and into the dressing was examined using a flow of artificial exudate (test solution) to a wound dressing attached to a temperature controlled (37°C) stainless steel plate over a 24 hr period. The fluid handling capacity of dressings was assessed both within the dressing and through the moisture vapour transmission rate (MVTR) properties at low flow rate (1ml/hr) and higher flow rate (2ml/hr) to simulate different wound exudate levels. A test system without the ODS on the wound bed platform and only the absorbent dressing in place served as the control. Testing was performed in triplicate.Results:No marked difference was observed for fluid handling capacity (absorption or MVTR) of the ODS and dressing system compared to the dressing control at  the low or higher flow rate.  This result confirms that the ODS component of the cTOT system does not interfere with fluid handling and fluid is transferred freely from the wound bed into a secondary dressing appropriate for the exudate levels.Discussion: cTOT is an adjunctive therapy that supports faster healing2–4 and pain reduction5 in non-healing hypoxic wounds.  This laboratory test simulating clinical use of the cTOT system with an absorbent dressing confirms that the ODS does not impede the flow of fluid from the wound bed to the dressing whilst providing supplementary oxygen to the wound.References:1. Schultz, G. S., Barillo, D. J., Mozingo, D. W. & Chin, G. A. Wound bed preparation and a brief history of TIME. Int Wound J 1, 19–32 (2004). 2. Carter, M. J. et al. Efficacy of Topical Wound Oxygen Therapy in Healing Chronic Diabetic Foot Ulcers: Systematic Review and Meta-Analysis. Adv Wound Care (New Rochelle) 12, 177–186 (2023). 3. Serena, T. E. et al. Topical oxygen therapy in the treatment of diabetic foot ulcers: a multicentre, open, randomised controlled clinical trial. J Wound Care 30, S7–S14 (2021). 4. Kaufman, H. et al. Topical oxygen therapy used to improve wound healing in a large retrospective study of wounds of mixed aetiology. Wounds International 12, 63–68 (2021). 5. Jebril, W. et al. Topical oxygen treatment relieves pain from hard-to-heal leg ulcers and improves healing: a case series. J Wound Care 31, 4–11 (2022).