Caring Wisely FY 2023 Project Contest

The Wave of the Future: Using Long-Wave Infrared Thermography to Prevent Hospital Acquired Pressure Injuries

Proposal Status: 


Executive Sponsor:

Arthur Dominguez Jr., DNP, MSN, RN, CEN

Vice President and Chief Nursing Officer of Adult Services

Project Lead(s)

Inpatient Wound and Ostomy Care Team (Parnassus Campus)

Team Manager: Jonathon Holte, MSN, RN, CWON

Team Members:

Skyler Bivens, BSN, RN-BC, CWOCN

Diane Sandman, MSN, FNP, CWOCN

Rachel Daniels, BS-N, RN, CWON

The inpatient wound and ostomy team is part of the clinical practice and research branch of the

Center for Nursing Excellence and Innovation, under the direction of Hildegarde (Hildy) M.

Schell-Chaple, PhD, RN, CCRN-K, CCNS, FAAN.


Background:Hospital Acquired Pressure Injuries (HAPIs) are the most common preventable hospital acquired condition. Impact on the UCSF Health system includes increased cost of care, increased readmission rates, and increased length of stay. Critically ill patients and patients with darkly pigmented skin are disproportionately affected by HAPIs, contributing to increased morbidity and mortality in these populations. At UCSF, the highest HAPI incidence is in the MSICU. Thermal imaging is a quantitative, objective, and non-invasive tool to detect early development of pressure injuries before visible signs are present. Objective:Utilize thermal imaging for early detection of pressure injuries to improve patient outcomes and provide equitable care for patients with darkly pigmented skin. Method: Modeling a study by Koerner et al. (2019) UCSF will implement thermal imaging in the MSICU for all new admissions as an adjunct to nursing skin assessment to identify temperature changes in high-risk anatomical locations indicating early pressure injury development. Earlier detection allows prompt initiation of targeted measures to prevent progression of injury and ensure community acquired pressure injuries are not incorrectly attributed to UCSF as HAPIs. Impact: Reduced incidence of HAPIs in the ICU, improved patient outcomes and satisfaction, preservation of revenue for the health system related to patient care costs, non-reimbursement, and litigation associated with HAPI development.


Pressure injuries are the most commonly occurring preventable event in the hospital setting and are among the five most common harm events to reach patients. Every year in the United States, over 2.5million people are affected by pressure injuries, and approximately 60,000 patients die as a consequence of pressure injury development and associated complications. Pressure injuries contribute to increased lengthof hospital stay, increased readmission rates, and higher costs of care. In addition to the physical impacts of pressure injuries including pain, delayed recovery, disfigurement, and infection risk, there is also a detrimental emotional impact for patients and families. The development of hospital acquired pressure injuries (HAPIs) is a quality-of-care indicator for a health system, which can affect Magnet recognition status, as well as public perception of patient safety at the institution. HAPI development additionally leads to an increased risk of litigation.

The National Pressure Injury Advisory Panel (NPIAP) determined that the cost of patient care for a singlepressure injury is between $20,900 - $151,700, and that the annual cost of pressure injurycare in the United States is $26.8 billion. In FY2022, UCSF had 203 hospital acquired pressure injuriesfor the adult inpatient population. According to the NPIAP data, the estimated financial impact to the UCSF Health system for FY2022, is $4.24 -$30.8 million in annual costs. These figures do not account for potential additional costsassociated with litigation or non-reimbursement. The NPIAP reports that there are approximately 17,000 lawsuits annually that are directly related to pressure injuries, and that it is the second most common claim following wrongful death (NPIAP, 2019). Additionally, according to the Centers for Medicare and Medicaid, pressure injuries are considered “never events,” which can lead to non-reimbursement.

Pressure injury identification can be confounded by delayed superficial or outward signs following injury occurrence. This is especially the case for deep tissue pressure injuries (DTPIs) which usually present approximately 48 hours following injury (Black 2018), however have been reported to appear anywhere from 1 to 7 days post-injury (Koerner et al. 2019). DTPIs are defined by the NPIAP as “Intact or non-intact skin with localized area of persistent non-blanchable deep red, maroon, purple discoloration or epidermal separation revealing a dark wound bed or blood-filled blister. Pain and temperature change often precede color changes. Discoloration may appear differently in darkly pigmented skin. This injury results from intense and/or prolonged pressure and shear forces at the bone-muscle interface”. In FY2022, UCSF had 72 hospital acquired DTPIs documented among adult inpatients. Using the most conservative estimate from the NPIAP, the cost to the health care system related to DTPIs in the fiscal year 2022 is more than $1.5 million. These estimates do not include additional lost revenue related to litigation or loss of reimbursement.


Earlier identification of skin and tissue damage promotes earlier intervention of appropriate interventions and better patient outcomes.The primary project goal is to detect tissue damage that is present upon hospitaladmission so that targeted, individualized care interventions can be implemented promptly to mitigate additional damage, and to correctly categorize the injury as present on admission and not hospital acquired. The use of long-wave infrared thermography (LWIT, or thermal imaging) will improve admission assessment and documentation, facilitate early pressure injury identification and intervention, and prevent inappropriately assigned financial responsibility for injuries present on admission that may otherwise have been classified as hospital acquired. This is especially important regarding DTPIs, for which signs of damage can take several days to appear to the surface of the skin following injury occurrence. DTPIs can present with either an increase or decrease in temperature compared withsurrounding skin/tissue, but are more likely to occur when temperatures are comparatively lower(Koerner et al. 2019). The use of thermal imaging technology provides measurable, objective assessment data compared to the traditional assessment methods of inspection and palpation alone.Quantitative benefits of implementation include reduction of HAPI rates, particularly DTPIs, reduction of costs/revenue preservationassociated with the care of HAPIs, prevention of the development of more severe pressureinjuries due to early detection, accurate temperature assessment tomonitor perfusion, inflammatory or ischemic status, and injury risk over time, as well asimprovement in the accuracy of injury assessment in individuals with darkly pigmented skin.Qualitative benefits include increased awareness of present on admission HAPIs/DTPIs amongstaff, avoidance of negative impact on patient/family mental health and stress associated with pressure injuries, preserved patient/family perception of care received and overall experience with the health system, improved patient/family satisfaction, as well as improved professional satisfaction and reduction of staff feelings of guilt related to a pressure injury occurring “on their watch”.


Standard practice for skin assessment includes visual inspection, palpation, and patient reports of pain, discomfort, or other sensory changes. The overall goal of skin assessment regarding pressure injuries is to promptly detect early abnormalities and implement preventive measures to mitigate skin and tissue damage and prevent progression to more severe injury (Black, 2018).

Visual assessment, especially early in pressure injury development, can be an unreliable method of detection, as pressure injuries are described as “bottom-up” injuries. Visual signs of pressure injury can be delayed following injury occurrence, which is especially the case for DTPIs, for which visual signs can take several days to appear following damage.

Another limitation of visual assessment is detection of early changes in individuals with darkly pigmented skin. Early signs of pressure injury such as erythema are more difficult to identify in darkly pigmented skin (Black, 2018). This is problematic as a decreased ability to identify early signs of pressure injury contributes to increased injury rates and more severe injury events among this patient population. According to the NPIAP 2019 Clinical Practice Guideline, several studies indicate that there is a higher rate of more severe pressure injuries (stage 3 and 4) among individuals with darker skin pigmentation, as well as higher mortality rates. It has also been reported that black patients have a higher pressure injury rate of 2.4% compared to 1.2-1.8% among other groups (Bauer et al. 2016). Due to challenges in visualizing pressure-related color changes in darkly pigmented skin, the NPIAP 2019 Clinical Practice Guideline includes the following statement: “when assessing darkly pigmented skin, consider assessment of skin temperature and sub-epidermal moisture as important adjunct assessment strategies.”

Palpation of the skin is performed to detect changes in texture such as induration, bogginess or temperature variations compared to adjacent tissue. As specified in the definition of DTPI, these changes may occur prior to visual changes. Despite the importance of assessing tissue temperature in early pressure injury identification palpation remains subjective, unreliable, and unquantifiable. The use of thermal imaging technology would mitigate variability in manual assessment to provide a reliable measure of temperature variations of the skin and underlying tissues. Using thermography to detect early temperature changes that occur before visible signs of damage would contribute to earlier implementation of intervention and prevention of injury progression.


The wound care team at UCSF Parnassus will implement the EHOB WoundVision Scout program, which uses LWIT to assess perfusion and metabolic activity beneath the skin to identify areas of damage before outward signs appear to the surface of the skin. WoundVision thermography detects temperature changes between injured skin/tissues compared to surrounding areas by visualizing emitted thermal energy in a noninvasive, noncontact, non-radiating method. The WoundVision Scout is a handheld, portable, FDA-approved device that captures visual and thermal images of skin, underlying tissues, and wounds via a combination of digital and long-wave infrared camera. Temperature assessment using the WoundVision Scout device has demonstrated reliability and reproducibility with intra- and interreader coefficients of variation of 1% and 2% (Langemo, 2017). Using relative temperature data, a quantitative measure of improvement or regression of a skin or tissue area can be assessed and monitored. Compared to the current standard of manual palpation for temperature assessment, the use of LWIT provides objective, reliable, and measurable data to identify temperature variations that indicate injury development.

Additionally, the 2021 NPIAP annual conference featured a presentation on the benefits of thermal imaging assessment in early pressure injury identification, especially for individuals with darkly pigmented skin (Black, Vargo, 2021).

HAPIs occur at higher rates among patients in critical care compared to patients in acute care units (Pittman et al. 2019). This is consistent at UCSF as well, with the highest HAPI rates occurring in medical-surgical intensive care units (MSICUs). This critical care area is the initial target population for WoundVision intervention, with the ability to scale to other care areas, such as cardiovascular ICUs and the emergency department. Implementation in the medical-surgical ICU will be modeled after a study by Koerner et al. (2019) during which all patients admitted to one of the institution’s ICUs were evaluated at time of admission using the WoundVision Scout device. The aim of this study, as would also be the goal of implementation at UCSF, is to identify temperature changes that indicate development of DTPI at the time of admission before visual signs occur. This will allow the hospital and its nurses to proactively initiate targeted care measures to prevent further development of injury, as well as to ensure that the injury is appropriately documented as present on admission. Anatomical locations at highest risk of DTPI development would be the focus of admission assessment with WoundVision Scout, including sacrum, coccyx, and calcanei with the addition of other areas as needed per individual patient risk factors.

Integrating thermal imaging technology into standard admission assessment practices will promote better patient outcomes, reduced incidence of harm events, and support revenue preservation for the health system related to patient care costs, non-reimbursement, and litigation associated with HAPI development.

Supporting Studies

The study referenced above by Koerner et al. (2019) took place in 2016 at Mt Carmel West Hospital over a 2-month period during which time 114 patients admitted to ICUs were assessed using WoundVision Scout over areas at highest risk of DTPI development, including bilateral heels, sacrum, and coccyx. During the two-month study, 12 areas of thermal variation were identified, two of which progressed to visual DTPI. Pressure injury prevention procedures had been implemented and are credited with preventing the development of additional visual DTPIs from occurring. Because the two visual DTPIs had been documented on admission, the pressure injury rate during the study period was zero with estimated total preserved revenue of approximately $194,860, which does not account for additional savings related to prevention of other visual DTPI development. A zero false-negative rate was also identified during the study, whereby none of the patients without areas of thermal variation later developed DTPIs. A related study conducted at Christus Trinity Mother Frances Health System in 2019 including 1701 patients demonstrated an 85% reduction in DTPI rates (19 fewer cases) over a 7-month period following implementation of WoundVision Scout during admission assessment (Jackson, 2019). Additionally, in a blinded prospective cohort study of 70 patients by Simman (2018), WoundVision Scout was used upon admission to a long-term acute care hospital and identified 4 areas of thermal variation that progressed to visual DTPIs. Estimated cost savings related to reimbursement loss were $172,720, not accounting for potential litigation costs that also may have arisen.

Additional Benefits to Patient Outcomes

The benefits of implementing WoundVision Scout in our health system extend beyond pressure injury identification and prevention. In addition to thermal assessment and photographic documentation, the WoundVision Scout also provides visual wound imaging to measure wound area. The use of LWIT for wound measurement provides more accurate and precise results compared to standard manual techniques, which is important in ensuring consistent measurements for comparison, as well as evaluating progress toward healing vs deterioration and possible need for treatment modification (Langemo et al. 2015).

Thermal imaging technology is also used in early detection of surgical site infection, another hospital acquired condition that contributes to increased length of stay, readmission rates, and costs. In a study by Shepard et al. (2013), it was calculated that the net loss in profits to Johns Hopkins Health System was between $4,147 and $22,239 per surgical site infection.

Additionally, LWIT can be used to assess perfusion as an indicator of viability of flap and graft sites, identify potential pending dehiscence of surgical incisions, and evaluate lower extremity perfusion before and after limb salvage procedures, including use as an indicator in determining the level of amputation to predict healing (Spence et al. 1981). Utility has also been demonstrated in screening for osteomyelitis, particularly among patients with diabetes (Chanmugam A et al., 2017). Furthermore, perfusion could be assessed pre- and post-op to identify potential injuries that may have developed in perioperative areas, especially surrounding high risk or prolonged procedures.


In a documented quote provided by the manufacturer (EHOB), $50,000 will include subscription to WoundVision Scout cloud software, the purchase of two handheld devices, device clinical training for staff, EMR integration set-up, and EMR integration subscription. Refer to the budget section below for detailed descriptions of each item, as well as standard cost values for each. 

Applying the lowest possible cost per pressure injury according to NPIAP ($20,900), and based on conservative estimates, this baseline cost is slightly higher than patient care costs the health system incurs related to approximately two hospital acquired pressure injuries, not including potential loss of reimbursement or litigation costs. The graph below demonstrates anticipated revenue preservation with a 10-30% reduction in HAPI rate in the first year of intervention, using the most conservative estimated cost per HAPI. Using the greatest estimated cost per HAPI, savings could increase sevenfold.


Following successful implementation of WoundVision Scout, the ongoing use of the system will be sustained by return on investment that is projected to substantially outweigh the cost of annual subscription to the software. Additionally, there is the potential for expansion to other hospital areas such as specialty ICUs, surgical departments, the emergency department, and other inpatient units, which could lead to even greater cost savings, increased prevention of hospital acquired conditions, and improved patient outcomes with the minimal upfront expense of purchasing additional handheld devices to link to the software.

Key process owners are the Inpatient Wound and Ostomy Team staff within the clinical practice and research branch of the Center for Nursing Excellence and Innovation, under the direction of Hildegarde (Hildy) M. Schell-Chaple, PhD, RN, CCRN-K, CCNS, FAAN. This program has been discussed with Dr. Young and Dr. Rosser of the plastic surgery service who have expressed interest in collaborating in its use.


The following quote with included products and services was negotiated with the manufacturer (EHOB). Confirmation documentation was obtained and can be provided to the review committee upon request. 

$50,000 to include:

1)      WoundVision Scout Cloud Software (standard value $34,000)

The 1-YR subscription license to the web-based, HIPAA compliant Scout Software Cloud includes integration with up to 5 Scout Imagers, unlimited users, unlimited data storage, free software upgrades, data hosting and software maintenance.

2)      WoundVision Scout Imaging Devices (standard value $18,000, per device $9,000 ea.)

The handheld visual and long-wave infrared imaging device works in conjunction with the Scout Cloud Software. The device purchase includes a 1-YR manufacturer warranty and preventative maintenance.

3)      WoundVision Scout Clinical Training for staff (standard value $2,000)

4)      EMR Integration Setup (standard value $10,000)

Setup and implementation of HL7 or SMART on FHIR EMR integration. Configuration includes inbound patient ADT from EMR to Scout Software and outbound patient images/data from Scout Software to EMR. Price is based on a minimum work effort of five days. If scope exceeds minimum work effort a separate agreement will be created.

5)      EMR Integration License (standard value $8,000)

A 1-YR EMR Integration Subscription License provides a RESTful web API to securely send and receive data between WoundVision and 3rd party HL7 compliant EMR systems. At minimum this license includes inbound patient ADT and outbound patient images/data.