Fluorescence imaging guided dressing change frequency during negative pressure wound therapy: a case series

Abstract

Objective: Knowledge of wound bioburden can guide selection of therapies, for example, the use of negative pressure wound therapy (NPWT) devices with instillation in a heavily contaminated wound. Wound and periwound bacteria can be visualised in real-time using a novel, non-contact, handheld fluorescence imaging device that emits a safe violet light. This device was used to monitor bacterial burden in patients undergoing NPWT. Methods: Diverse wounds undergoing NPWT were imaged for bacterial (red or cyan) fluorescence as part of routine wound assessments. Results: We assessed 11 wounds undergoing NPWT. Bacterial fluorescence was detected under sealed, optically-transparent (routine) adhesive before dressing changes, on foam dressings, within the wound bed, and on periwound tissues. Bacterial visualisation in real-time helped to guide: (1) bioburden-based, personalised treatment regimens, (2) clinician selection of NPWT, with or without instillation of wound cleansers, and (3) the extent and location of wound cleaning during dressing changes. The ability to visualise bacteria before removal of dressings led to expedited dressing changes when heavy bioburden was detected and postponement of dressing changes for 24 hours when red fluorescence was not observed, avoiding unnecessary disturbance of the wound bed. Conclusion: Fluorescence imaging of bacteria prompted and helped guide the timing of dressing changes, the extent of wound cleaning, and selection of the appropriate and most cost-effective NPWT (standard versus instillation). These results highlight the capability of bacterial fluorescence imaging to provide invaluable real-time information on a wound's bioburden, contributing to clinician treatment decisions in cases where bacterial contamination could impede wound healing.

Use of a bacterial fluorescence imaging system to target wound debridement and accelerate healing: a pilot study

“…This is not the first study to report bacterial fluorescence from the periwound region. In a clinical trial of 50 hard-to-heal (chronic) wounds, Raizman et al reported fluorescence indicative of bacteria in the periwound of 89% of wounds 20 and Farhan et al detected bacteria in the peripheries of 88% of wounds. 25 However, we show here for the first time that the presence of periwound bacterial loads is associated with delayed healing and fluorescenceguided debridement of these regions to eliminate fluorescent signature from bacteria was associated with a shift of wounds onto a healing trajectory.…”

“…18 Wounds exhibiting red or cyan fluorescence are considered to have moderate to heavy (>10 4 CFU/g) levels of bacteria. 13,[20][21][22] The wound care clinician captured standard and fluorescence images after training on device use and image interpretation. 18,23 A range finder on the device was used to ensure that all images were taken at the optimal imaging distance (8-12cm).…”

“…19 The immediate information on wound area provided by the measurement software enables clinicians to assess rates of healing and efficacy of treatments selected. 20 The aim of this 12-week case series was to evaluate the utility of fluorescence imaging to detect bacterial burden in excess of 10 4 CFU/g in wounds, monitor changes in wound area, and inform treatment selection of lower extremity hard-to-heal wounds that were negative for clinical signs and symptoms of infection. Fluorescence (FL) imaging provided information on bacterial presence that was used to guide debridement, dressing selection and/or decision to use antimicrobials or antibiotics.…”

Use of a bacterial fluorescence imaging device: wound measurement, bacterial detection and targeted debridement

“…To overcome this challenge, a disposable drape attachment can be used, and work has demonstrated its effectiveness in achieving the required darkness. 16…”

“…The MolecuLight i:X imaging device is a novel, handheld, point-of-care diagnostic imaging tool designed to accurately and digitally measure wound areas and to provide objective, real-time evidence on the presence and location of high bacterial loads (both planktonic and in biofilm. [11][12][13][14][15][16] This provides objective documentation, performed at the bedside, during which the device captures an image in a format compatible with most electronic medical records (EMR) systems. The device contains built-in digital wound measurement software and emits a safe violet light which is used for non-invasive, contrast agent free fluorescence imaging to identify regions with concerning levels of bacteria in real-time.…”