A New Way to Look at Wounds in the COVID-19 Era: When PPE Has Eliminated Smell From the Infection Equation

In the last year, the COVID-19 pandemic has disrupted our normal wound care practices and procedures. In this article, two seasoned wound care specialists describe the changes they have endured resulting from the pandemic and how they are using portable, point-of-care imaging technology to overcome additional challenges brought on by the pandemic.

Just over a year ago, the World Health Organization declared COVID-19 a pandemic.¹ The onset of the pandemic forced a significant shift in how we were able to care for our patients’ wounds while limiting viral spread. Below, we describe the challenges of wound assessment and patient engagement that practitioners have experienced due to the COVID-19 pandemic, as well as how we leveraged technology to push through some of these barriers.

For a related Speaking of Wounds podcast on this topic, click here.

Challenges During COVID-19

Multisensory wound assessment is no longer possible. Prior to the onset of the pandemic, it was standard practice for clinicians to integrate multiple sensory inputs when evaluating a patient’s wound for signs of infection. We typically visualize the wound for signs of redness or swelling, touch the wound to determine whether it is warm, or smell wound drainage to detect the distinct, pungent odor indicative of wound infection.

However, with the onset of the pandemic, extra precautions were put in place including the mandatory use of layers of personal protective equipment (PPE) before encountering a patient. These additional layers of protection include an N95 mask, face shield, gown and even an extra pair of gloves. With these added barriers, the multisensory aspect of wound assessment has been taken away as it is no longer possible to rely on wound odor to determine if a wound is infected. Our capacity to assess the wound effectively has been hindered.

Interestingly, we still instinctively find ourselves “bringing it to the nose,” only to end up with wound drainage on an N95 mask. This lesson was learned many times and meant that our practices of assessment for infection and bioburden needed to adapt, to reduce reliance on sensory inputs.

Patients are increasingly reluctant to seek care, are more isolated, and have become more reliant on antibiotics or antimicrobials. Efforts to protect those most vulnerable to COVID-19 has translated to a drastic reduction in the number of patient visits and elective procedures in hospitals and has left our patients in long-term care facilities separated from their families and shielded from their care providers by layers of PPE. Unfortunately, the risk factors that put the elderly at such high risk for COVID-19 mortality also make them more susceptible to severe deterioration of wounds, wound infection, and development of sepsis.² Reduced immune function and comorbidities mean that the typical signs and symptoms of infection may not be readily detected.^3,4 Timely detection of infection in wounds, particularly of pressure injuries or hidden abscesses, can mean the difference between life and death in these patients. The inability to rely on and interpret odor as an indicator of infection makes the diagnosis of infection even more challenging.

With increased fear of exposure to COVID-19, many patients have felt isolated and are more likely to avoid seeking care from their wound care provider. This is true in both the hospital and private office setting. Indeed, another “wave” is coming our way—but this time it is the wave of deteriorated wounds that will likely need more complex care due to delayed treatment or due to COVID related skin manifestations suffered by post-COVID survivors. As a result, many of these patients will face more severe infections.⁵ The rise in wound amputations is already being seen^6-8, as is a rise in antibiotic prescribing “just in case” for patients unable or unwilling to come for in-person visits.

Now more than ever, we need strategies that will help patients clearly understand the status of their wound as well as the importance of engaging with their wound care providers, working together to prevent complications from developing and reducing reliance on antibiotics or antimicrobials.  

Integrating and Leveraging Bedside Imaging of Bacterial Burden

Rather than use often inaccurate representations of high bacterial loads (e.g. odor), we turn to diagnostic imaging to help overcome some of the disruptions to standard practice. Point-of-care fluorescence imaging (MolecuLight i:X) provides a safe, non-invasive direct visual method of objectively detecting bacteria at levels known to delay healing (>10⁴ CFU/g)^9-12 or progress to systemic infections. The fluorescence lets us know not only that bacteria is present, but also where it is located in and around the wound—and so often we find it in regions we would not expect or locations appearing benign to the naked eye.

When we see a preponderance of a red (most bacteria) or cyan (which uniquely indicates presence of Pseudomonas aeruginosa) on fluorescence images on the wound bed, we want to share this information with our team and start wound progression through wound hygiene.^11,13-15 We may then consider how to proceed with conservative sharp debridement, if that is possible for the patient.

If debridement is not enough to fully remove the red or cyan signals, we may then consider a targeted tissue culture, selecting a site in the wound where bacteria continue to fluoresce after conservative sharp debridement. All too often, high bacterial loads are left behind in wounds, which could have been removed if the clinician had the appropriate information.^16,17 If we want to “clean it like we mean it,” we need to know where the bacteria are, and evaluate how effective our cleaning truly was. In our experiences, treatment plans change between 75–95% of the time based on the imaging information. This is consistent with published literature^10,17-19 and provider reports.These better informed treatment plans have improved our wound outcomes.

Because the device is handheld, we can carry it around in our scrubs pockets so it can be taken from patient to patient across various facilities and we can easily wipe it down between visits. Due to the non-invasive visual exam, the fluorescence imaging is painless for both the patient and the clinician to use.  

Engaging more effectively with patients. While covered in layers of PPE, it has been challenging to connect with patients when they cannot see a reassuring smile. In our experience, the fluorescence images provide an opportunity to build this connection. The images are shared with patients and the colors explained to them. They can appreciate that red is not what we want to see, and it makes their infection risk, and need for further treatments, easier to understand. This has been particularly helpful for those patients with neuropathies or other comorbidities that suppress the typical signs of infection. They may not feel the pain or swelling, but when they see red or cyan, there is instant feedback that more treatment must be done. This has enabled a more collaborative approach to wound care as patients are seeing the same information that we are receiving in real time.

An example of this collaborative, real time decision making is shown in Figure 1. This patient was receiving treatment for a venous leg ulcer that had some evidence of necrosis. The wound did not appear to have major signs of infection, but when we turned the lights off and turned on the fluorescence, we immediately saw a vast amount of red and cyan fluorescence in the wound, indicating a high level of bacteria present, including Pseudomonas aeruginosa. Saline was used to clean the wound (as is standard practice) and another set of images was taken. The real-time feedback from the fluorescence images helped us to realize that a stronger cleanser was needed. A decision was made at the point-of-care to switch to a modified sodium hypochlorite solution. We immediately noticed a drastic reduction in the Pseudomonas signal (cyan), but there was still a significant amount of red fluorescence that persisted.

These images helped to educate the patient and explain the need for further debridement. Because the patient had been educated to know that “red was bad,” he was agreeable to the additional interventions required. This wound went on to heal.

Supporting antimicrobial stewardship. Across all our care settings, the fluorescence imaging device has become an integral part of our antimicrobial stewardship practice.²⁰ The imaging device is taken with us from patient to patient and facility to facility and has become an important assessment tool when determining the need for culture or use of antimicrobials. Elderly individuals typically develop wounds due to some underlying metabolic dysfunction.²¹ The use of antimicrobials in these individuals is particularly common because of the fear of infection developing. With the rise in antimicrobial resistance, we know the trend of “just in case” prescribing cannot be maintained. This is especially important for elderly patients, who can experience serious adverse effects of antibiotics. Promising evidence has emerged for a decreased reliance of antibiotics²² when fluorescence imaging is added to the standard of care. We are monitoring our own practices to see if a similar impact is observed.

Informing the larger wound care team about bacterial burden. The onset of COVID-19 has changed the way we interact with our patients, in addition to the way that our staff engages with each other. Staff scheduling was altered to reduce the number of staff working near each other and to limit shift overlap; team huddles and meetings were replaced with emails, phone calls and other contactless methods of sharing the status of our patients. These changes have made it tougher to organize patient care among staff. Point-of-care fluorescence imaging has been extremely valuable when coordinating care with our colleagues in both the long-term care setting as well as in the inpatient and outpatient hospital environment. Across these care settings, we use the fluorescence images to help us immediately decide what treatments are needed and whether we need to use an antimicrobial dressing. We also use the images from prior visits to understand the progress of the wound and track which treatments have been most effective.

The fluorescence images have been especially helpful in the hospital inpatient and long-term care settings to expedite treatment. When we see red in images, it makes it easier for us to access specialty services like infectious disease and plastics consults, expedite a referral and expedite intervention based on that image. The images also enable us to order the most appropriate referral for physician consults (i.e. surgeon, infectious disease or other) to get the expedited treatment moving.

Images lead to further interventions but also further investigations. Probing into a region of red fluorescence has led to discoveries of hidden abscesses in these vulnerable patients; we also employ additional diagnostics when persistent red is present after debridement. These potentially include X-ray, blood work for C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), complete blood count (CBC), and/or targeted culture. Real-time fluorescence imaging provides an easy way for us to share information with one another to help us to continue to make evidence-informed decisions that support the best outcomes for our patients.  

What Does the Future Hold?  

Each day, we are heartened to hear of the rise in the number of vaccinated individuals and slow but steady decrease in number of patients hospitalized. With these encouraging trends, it seems likely that the world will resume some semblance of “normal” in the not-too-distant future. But what will normal look like for wound care providers? While we may be keen to stop donning our N95 masks and re-establish our connections with patients, we know that things may never return to their previous state. In spite of the N95 masks, is it really healthy for wound clinicians to inhale wound drainage odor to check for symptoms of infection?

To continue to provide the best quality wound care to our patients, we must continue to embrace and adapt to the challenges we have endured over the last year. Fluorescence imaging is now fully integrated into our clinical workflow as it has become a medically necessary and complimentary tool in our wound care practice.

Rosemary Hill is a WOCN who has been treating complex wounds in the inpatient and outpatient setting in Vancouver, Canada for over 35 years.

Martha R. Kelso is CEO of Wound Care Plus, LLC and leads a team of advanced wound care consultants and specialists who provide bedside wound care to patients in long-term care, assisted living, inpatient acute care, and a multitude of other sites of care across the United States.

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