Exploring the similarities and differences of burn registers globally: Results from a data dictionary comparison study.

INTRODUCTION: Pooling and comparing data from the existing global network of burn registers represents a powerful, yet untapped, opportunity to improve burn prevention and care. There have been no studies investigating whether registers are sufficiently similar to allow data comparisons. It is also not known what differences exist that could bias analyses. Understanding this information is essential prior to any future data sharing. The aim of this project was to compare the variables collected in countrywide and intercountry burn registers to understand their similarities and differences. METHODS: Register custodians were invited to participate and share their data dictionaries. Inclusion and exclusion criteria were compared to understand each register population. Descriptive statistics were calculated for the number of unique variables. Variables were classified into themes. Definition, method, timing of measurement, and response options were compared for a sample of register concepts. RESULTS: 13 burn registries participated in the study. Inclusion criteria varied between registers. Median number of variables per register was 94 (range 28 - 890), of which 24% (range 4.8 - 100%) were required to be collected. Six themes (patient information, admission details, injury, inpatient, outpatient, other) and 41 subthemes were identified. Register concepts of age and timing of injury show similarities in data collection. Intent, mechanism, inhalational injury, infection, and patient death show greater variation in measurement. CONCLUSIONS: We found some commonalities between registers and some differences. Commonalities would assist in any future efforts to pool and compare data between registers. Differences between registers could introduce selection and measurement bias, which needs to be addressed in any strategy aiming to facilitate burn register data sharing. We recommend the development of common data elements used in an international minimum data set for burn injuries, including standard definitions and methods of measurement, as the next step in achieving burn register data sharing.

The Effects of the COVID-19 Pandemic on Burn Clinic.

The COVID-19 pandemic has led to anxiety and fears for the general public. It is unclear how the behavior of people with acute burns and the services available to them has changed during the pandemic. The aim of our observational study was to evaluate our clinic's experience with patients presenting with burns during the first 10 months of the COVID-19 pandemic and determine if delays in presentation and healthcare delivery exist within our burn population. Patients referred to our clinic from March 1, 2020 to December 15, 2020 were reviewed for time of presentation after injury. We defined a true delay in presentation of >5 days from date of injury to date of referral for patients who were not inpatients at our facility or received initial care elsewhere prior to referral. Of the 246 patients who were referred to our clinic, during this time period, 199 patients (80.89%) attended their appointments. Our in-person clinic volume from referrals increased in July 2020 with a sharp decrease in August 2020. Our total clinic volume decreased in 2020 from 2019 by about 14%. Referrals to our clinic decreased in 2020 from 2019 by about 34%. Video telehealth visits did not account for the decrease in visits. There was low incidence of delays in presentation to our clinic during the pandemic. Additional investigation is necessary to see if the incidence of burn injury decreased. Despite the pandemic, our clinic remained ready and open to serve the burn population.

Vulvovaginal involvement in Stevens-Johnson syndrome and toxic epidermal necrolysis: management and techniques used to reduce gynecologic sequelae.

BACKGROUND: Vulvovaginal involvement in Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) is common, likely underdiagnosed, and can result in severe sequelae if not managed acutely. There are few studies on acute management of vulvovaginal SJS/TEN. Current recommendations are predominantly based on expert opinion. We aimed to determine the frequency of vulvovaginal involvement in SJS/TEN at a single institution, identify treatment modalities, and assess outcomes at a tertiary care burn center. METHODS: This is a retrospective review of vulvovaginal SJS/TEN cases between 2009 and 2019. Demographic and clinical data including exam findings, treatment regimens, and outpatient follow-up were collected from the electronic medical record. RESULTS: Vulvovaginal involvement was observed in 12.7% (19/149) of cases of female patients with SJS/TEN. The mean age was 38.7 years (SD 23.6), and 21% (4/19) of patients were pediatric (age 9-18). Vulvar involvement was seen in 47.3% (9/19), and vulvar plus vaginal involvement was reported in 42.1% (8/19). Treatment regimens were variable until 2017, at which time institutional guidelines were implemented including application of ultrapotent topical steroid, vaginal estrogen, and menstrual suppression. Gynecology follow-up occurred in 15.7% (3/19) of cases. One complication of superficial vaginal agglutination was noted and was successfully treated in the office with blunt dissection. CONCLUSION: The most common treatment modalities employed at our institution included application of ultrapotent topical steroid, vaginal estrogen, and menstrual suppression. While follow-up was limited for our patient population, we propose an algorithm to prevent long-term sequalae of vulvovaginal SJS/TEN. Gynecologic surveillance is recommended to reduce urogynecologic sequelae.

No Difference in Morbidity or Mortality Between Octogenarians and Other Geriatric Burn Trauma Patients.

BACKGROUND: Geriatric burn trauma patients (age ≥65 years) have a 5-fold higher mortality rate than younger adults. With the population of the US aging, the number of elderly burn and trauma patients is expected to increase. A past study using the National Burn Repository revealed a linear increase in mortality for those >65 years old. We hypothesized that octogenarians with burn and trauma injuries would have a higher rate of in-hospital complications and mortality, than patients aged 65-79 years old. METHODS: The Trauma Quality Improvement Program (2010-2016) was queried for burn trauma patients. To detect mortality risk a multivariable logistic regression model was used. RESULTS: From 282 patients, there were 73 (25.9%) octogenarians and 209 (74.1%) aged 65-79 years old. The two cohorts had similar median injury severity scores (16 vs. 15 in octogenarians, P = .81), total body surface area burned (P = .30), and comorbidities apart from an increased smoking (12.9% vs. 4.1%, P = .04) and decreased hypertension (52.2% vs. 65.8%, P = .04) in the younger cohort. Octogenarians had similar complications, including acute respiratory distress syndrome, pulmonary embolism, deep vein thrombosis (P > .05), and mortality (15.1% vs. 10.5%, P = .30), compared to the younger cohort. Octogenarians were not associated with an increased mortality risk (odds ratio 1.51, confidence interval 0.24-9.56, P = .67). DISCUSSION: Among burn trauma patients ≥65 years, age should not be a sole predictor for mortality risk. Continued research is necessary in order to determine more accurate approaches to prognosticate mortality in geriatric burn trauma patients, such as the validation and refinement of a burn-trauma-related frailty index.

Helmets Protect Pediatric Bicyclists From Head Injury and Do Not Increase Risk of Cervical Spine Injury.

OBJECTIVES: Only 21 states have mandatory helmet laws for pediatric bicyclists. This study sought to determine the incidence of helmeted riders among pediatric bicyclists involved in a collision and hypothesized the risk of a serious head and cervical spine injuries to be higher in nonhelmeted bicyclists (NHBs) compared with helmeted bicyclists (HBs). METHODS: The Pediatric Trauma Quality Improvement Program (2014-2016) was queried for pediatric (age <16 years) bicyclists involved in a collision. Helmeted bicyclists were compared with NHBs. A serious injury was defined by an abbreviated injury scale grade of greater than 2. RESULTS: From 3693 bicyclists, 3039 (82.3%) were NHBs. Compared with HBs, NHBs were more often Black (21.6% vs 3.8%, P < 0.001), Hispanic (17.5% vs 9.3%, P < 0.001), without insurance (4.6% vs 2.4%, P = 0.012), and had a higher rate of a serious head injury (24.6% vs 9.3%, P < 0.001). Both groups had similar rates of complications and mortality (P > 0.05). The associated risk of a serious head (odds ratio = 3.17, P < 0.001) and spine injury (odds ratio = 0.41, P = 0.012) were higher and lower respectively in NHBs. Associated risks for cervical spine fracture or cord injury were similar (P > 0.05). CONCLUSIONS: Pediatric bicyclists involved in a collision infrequently wear helmets, and NHBs was associated with higher risks of serious head injury. However, the associated risk of serious spine injury among NHBs was lower. The associated risks for cervical spine fracture or cervical cord injuries were similar. Nonhelmeted bicyclists were more likely to lack insurance and to be Black or Hispanic. Targeted outreach programs may help decrease the risk of injury, especially in at-risk demographics.

Characterizing reduced scattering coefficient of normal human skin across different anatomic locations and Fitzpatrick skin types using spatial frequency domain imaging.

SIGNIFICANCE: Spatial frequency domain imaging (SFDI), a noncontact wide-field imaging technique using patterned illumination with multiple wavelengths, has been used to quantitatively measure structural and functional parameters of in vivo tissue. Using SFDI in a porcine model, we previously found that scattering changes in skin could potentially be used to noninvasively assess burn severity and monitor wound healing. Translating these findings to human subjects necessitates a better understanding of the variation in "baseline" human skin scattering properties across skin types and anatomical locations. AIM: Using SFDI, we aim to characterize the variation in the reduced scattering coefficient (µs') for skin across a range of pigmentation and anatomic sites (including common burn locations) for normal human subjects. These measurements are expected to characterize baseline human skin properties to inform our use of SFDI for clinical burn severity and wound healing assessments. APPROACH: SFDI was used to measure µs' in the visible- and near-infrared regime (471 to 851 nm) in 15 subjects at 10 anatomical locations. Subjects varied in age, gender, and Fitzpatrick skin type. RESULTS: For all anatomical locations, the coefficient of variation in measured µs' decreased with increasing wavelength. High intersubject variation in µs' at visible wavelengths coincided with large values of the melanin extinction coefficient at those wavelengths. At 851 nm, where intersubject variation in µs' was smallest for all anatomical locations and absorption from melanin is minimal, significant intrasubject differences in µs' were observed at the different anatomical locations. CONCLUSIONS: Our study is the first report of wide-field mapping of human skin scattering properties across multiple skin types and anatomical locations using SFDI. Measured µs' values varied notably between skin types at wavelengths where absorption from melanin was prominent. Additionally, µs' varied considerably across different anatomical locations at 851 nm, where the confounding effects from melanin absorption are minimized.

No Difference in Mortality Between Level I and II Trauma Centers for Combined Burn and Trauma.

BACKGROUND: Trauma patients with burn injuries have higher morbidity and mortality rates compared with patients who solely experience burn or trauma injuries. There is a paucity of data regarding burn-trauma (BT) patient outcomes at level I (LI) trauma centers compared with level II (LII) centers. We hypothesized that BT patients at LI trauma centers have lower mortality rates than those at LII trauma centers. METHODS: The Trauma Quality Improvement Program (2010-2016) was queried for patients aged ≥18 y who had BT injuries. Patients treated at an LI were compared with those at an LII center with a primary outcome of in-hospital mortality. Secondary outcomes included hospital length of stay (LOS) and intensive care unit (ICU) LOS. A multivariable logistic regression analysis was used to identify factors associated with all-cause mortality. RESULTS: From 1971 BT patients, 1540 (78%) were treated at an LI trauma center, and 431 (22%) at an LII center. Compared with LII centers, LI BT patients had a longer median LOS (10 versus 7 d; P < 0.001) and ICU LOS (5 versus 4 d; P < 0.001). Both LI and LII centers had similar mortality rates (8.5% versus 7.0%; P = 0.300). On multivariable analysis, receiving care at an LI trauma center was not associated with decreased mortality (odds ratio 0.79, 95% confidence interval 0.42-1.48; P = 0.456). CONCLUSIONS: We report that LI trauma center BT patients had an increased hospital and ICU LOS compared with those at LII centers. However, there was no significant difference in mortality between patients cared for at LI and LII trauma centers in risk-adjusted models.

Spatial Frequency Domain Imaging (SFDI) of clinical burns: A case report.

While visual assessment by a clinician is the standard of care for burn severity evaluations, new technologies at various stages of development are attempting to add objectivity to this practice by quantifying burn severity. Assessment accuracy generally improves after the burn injury has progressed, but early assessments that correctly identify superficial partial and deep partial burns have the potential to lead to more prompt treatments and shorter recovery times. To date, Spatial Frequency Domain Imaging (SFDI) has only been used in animal models of burns, but has shown the potential to categorize burns accurately at earlier time points. Here we examine the potential for SFDI to assess burn severity in clinical patients. We also utilize Laser Speckle Imaging (LSI), an FDA cleared non-invasive imaging technology that typically measures blood perfusion in order to evaluate burns in clinical patients. We present a case series of two patients, both with partial thickness burns of varying severity. Partial thickness burns are often difficult for clinicians to categorize based on visual appearance alone. SFDI and LSI were both performed on each patient at approximately 24 and 72 h after their respective burn incidents. Each technique was able to render spatially resolved information that enabled improved assessment accuracy for each burn. This represents the first publication of SFDI applied to clinical burn patients after being successfully utilized in animal models, and highlights the potential for SFDI as a feasible tool for the timely categorization of burn severity.

Analysis of non-obstetric vaginal and vulvar trauma: risk factors for operative intervention.

Vaginal and vulvar trauma may occur accidentally or because of an act of violence. Due to its rarity, little is known about risk factors effecting need for operative intervention. We sought to perform a large descriptive analysis of adult non-obstetric vulvovaginal trauma (VVT) and elucidate risk factors for requiring operative intervention. A retrospective analysis of the National Trauma Data Bank was performed between 2007 and 2015. Patients ≥ 16 years old with vaginal or vulvar trauma were identified. Risk factors for surgical intervention were identified using a multivariable logistic regression analysis. From 2,040,235 female patients, 2445 (< 0.2%) were identified to have VVT with the majority being injury to the vagina (68.6%). In patients with injury to the vagina, age > 65 (OR = 0.41, CI 0.26-0.62, p < 0.001), Injury Severity Score > 25 (OR = 0.66, CI 0.50-0.86, p = 0.01) and victims of rape (OR = 0.39, 95% CI 0.26-0.57, p < 0.001) were less likely to require operative intervention. In patients with injury to the vulva, age > 65 (OR = 0.45, CI 0.21-0.94, p = 0.02), victims of rape (OR = 0.26, CI 0.08-0.87, p = 0.01) and gunshot violence (OR = 0.10, CI 0.02-0.59, p = 0.02) were less likely to require operative intervention, but those with a concomitant injury to the vagina were more likely to require operative intervention (OR = 2.56, CI 1.63-4.03, p < 0.001). Injuries to the vagina or vulva occur in < 0.2% of traumas. Interestingly, in both vulvar and vaginal trauma, older age, and involvement in rape were associated with lower risk for operative intervention. A combined injury to the vagina and vulva increases the need for operative intervention.

Spatial frequency domain imaging: a quantitative, noninvasive tool for in vivo monitoring of burn wound and skin graft healing.

There is a need for noninvasive, quantitative methods to characterize wound healing in the context of longitudinal investigations related to regenerative medicine. Such tools have the potential to inform the assessment of wound status and healing progression and aid the development of new treatments. We employed spatial frequency domain imaging (SFDI) to characterize the changes in optical properties of tissue during wound healing progression in a porcine model of split-thickness skin grafts and also in a model of burn wound healing with no graft intervention. Changes in the reduced scattering coefficient measured using SFDI correlated with structural changes reported by histology of biopsies taken concurrently. SFDI was able to measure spatial inhomogeneity in the wounds and predicted heterogeneous healing. In addition, we were able to visualize differences in healing rate, depending on whether a wound was debrided and grafted, versus not debrided and left to heal without intervention apart from topical burn wound care. Changes in the concentration of oxy- and deoxyhemoglobin were also quantified, giving insight into hemodynamic changes during healing.

Burn wound classification model using spatial frequency-domain imaging and machine learning.

Accurate assessment of burn severity is critical for wound care and the course of treatment. Delays in classification translate to delays in burn management, increasing the risk of scarring and infection. To this end, numerous imaging techniques have been used to examine tissue properties to infer burn severity. Spatial frequency-domain imaging (SFDI) has also been used to characterize burns based on the relationships between histologic observations and changes in tissue properties. Recently, machine learning has been used to classify burns by combining optical features from multispectral or hyperspectral imaging. Rather than employ models of light propagation to deduce tissue optical properties, we investigated the feasibility of using SFDI reflectance data at multiple spatial frequencies, with a support vector machine (SVM) classifier, to predict severity in a porcine model of graded burns. Calibrated reflectance images were collected using SFDI at eight wavelengths (471 to 851 nm) and five spatial frequencies (0 to 0.2 mm - 1). Three models were built from subsets of this initial dataset. The first subset included data taken at all wavelengths with the planar (0 mm - 1) spatial frequency, the second comprised data at all wavelengths and spatial frequencies, and the third used all collected data at values relative to unburned tissue. These data subsets were used to train and test cubic SVM models, and compared against burn status 28 days after injury. Model accuracy was established through leave-one-out cross-validation testing. The model based on images obtained at all wavelengths and spatial frequencies predicted burn severity at 24 h with 92.5% accuracy. The model composed of all values relative to unburned skin was 94.4% accurate. By comparison, the model that employed only planar illumination was 88.8% accurate. This investigation suggests that the combination of SFDI with machine learning has potential for accurately predicting burn severity.

Risk Factors for Post-Operative Sepsis and Septic Shock in Patients Undergoing Emergency Surgery.

Background: Sepsis after emergency surgery is associated with a higher mortality rate than elective surgery, and total hospital costs increase by 2.3 times. This study aimed to identify risk factors for post-operative sepsis or septic shock in patients undergoing emergency surgery. Methods: A retrospective cohort analysis was performed using the National Surgical Quality Improvement Program (NSQIP) by identifying patients undergoing emergency surgery between 2012 and 2015 and comparing those who developed post-operative sepsis or septic shock (S/SS) with those who did not. Patients with pre-operative sepsis or septic shock were excluded. Multiple logistic regression was used to identify risk factors for the development of S/SS in patients undergoing non-elective surgery. Results: Of 122,281 patients who met the inclusion criteria, 2,399 (2%) developed S/SS. Risk factors for S/SS were American Society of Anesthesiologists Physical Status (ASA PS) class 2 or higher (odds ratio [OR] 2.57; 95% confidence interval [CI] 2.19-3.02; p < 0.0001), totally dependent (OR 2.00, 95% CI 1.38-2.83; p = 0.00021) or partially dependent (OR 1.62, 95% CI 1.35-2.00; p < 0.0001) functional status, and male gender (OR 1.31; 95% CI 1.18-1.45; p < 0.0001). Compared with colorectal procedures, patients undergoing pancreatic (OR 2.33, CI 1.40-3.87; p = 0.00108) and small intestine (OR 1.27; CI 1.12-1.44; p = 0.00015) surgery were more likely to develop S/SS. Patients undergoing biliary surgery (OR 0.38; CI 0.30-0.48; p < 0.0001) were less likely to develop S/SS. Conclusions: Risk factors for the development of sepsis or septic shock are ASA PS class 2 or higher, partially or totally dependent functional status, and male gender. Emergency pancreatic or small intestinal procedures may confer a higher risk. Greater vigilance and early post-operative screening may be of benefit in patients with these risk factors.

Impact of hemoglobin breakdown products in the spectral analysis of burn wounds using spatial frequency domain spectroscopy.

Burn wounds and wound healing invoke several biological processes that may complicate the interpretation of spectral imaging data. Through analysis of spatial frequency domain spectroscopy data (450 to 1000 nm) obtained from longitudinal investigations using a graded porcine burn wound healing model, we have identified features in the absorption spectrum that appear to suggest the presence of hemoglobin breakdown products, e.g., methemoglobin. Our results show that the calculated concentrations of methemoglobin directly correlate with burn severity, 24 h after the injury. In addition, tissue parameters such as oxygenation (StO2) and water fraction may be underestimated by 20% and 78%, respectively, if methemoglobin is not included in the spectral analysis.

Evaluating clinical observation versus Spatial Frequency Domain Imaging (SFDI), Laser Speckle Imaging (LSI) and thermal imaging for the assessment of burn depth.

While clinical examination is needed for burn severity diagnosis, several emerging technologies aim to quantify this process for added objectivity. Accurate assessments become easier after burn progression, but earlier assessments of partial thickness burn depth could lead to earlier excision and grafting and subsequent improved healing times, reduced rates of scarring/infection, and shorter hospital stays. Spatial Frequency Domain Imaging (SFDI), Laser Speckle Imaging (LSI) and thermal imaging are three non-invasive imaging modalities that have some diagnostic ability for noninvasive assessment of burn severity, but have not been compared in a controlled experiment. Here we tested the ability of these imaging techniques to assess the severity of histologically confirmed graded burns in a swine model. Controlled, graded burn wounds, 3cm in diameter were created on the dorsum of Yorkshire pigs (n=3, 45-55kg) using a custom-made burn tool that ensures consistent pressure has been employed by various burn research groups. For each pig, a total of 16 burn wounds were created on the dorsal side. Biopsies were taken for histological analysis to verify the severity of the burn. Clinical analysis, SFDI, LSI and thermal imaging were performed at 24 and 72h after burn to assess the accuracy of each imaging technique. In terms of diagnostic accuracy, using histology as a reference, SFDI (85%) and clinical analysis (83%) performed significantly better that LSI (75%) and thermography (73%) 24h after the burn. There was no statistically significant improvement from 24 to 72h across the different imaging modalities. These data indicate that these imaging modalities, and specifically SFDI, can be added to the burn clinicians' toolbox to aid in early assessment of burn severity.

Analysis of trauma patients with unplanned returns to the operating room.

OBJECTIVES: Trauma patients undergoing damage-control surgery may have a planned return to the operating room. In contrast, little is known about unplanned returns to the operating room (uROR) in trauma. The aim of this study was to identify risk factors for uROR in trauma patients. It is hypothesized that blunt trauma patients with uROR have higher mortality when compared to penetrating trauma patients with uROR. Additionally, it is hypothesized that trauma patients with uROR after thoracotomy have higher mortality than patients with uROR after laparotomy. MATERIAL AND METHODS: A retrospective analysis of the National Trauma Data Bank from 2011-2015 including any adult patient with an uROR was performed. RESULTS: From 3.447.320 patients, 9.269 (0.2%) were identified to have uROR. In a multivariable logistic regression analysis, 27 independent predictors were identified for risk of uROR with the strongest independent risk factor being compartment syndrome (OR= 10.50, CI= 9.35-11.78, p <0.001). Blunt (compared to penetrating) mechanism was associated with higher risk for mortality in patents with uROR (OR= 1.69, CI= 1.14-2.51, p <0.001) as was re-incision thoracotomy (RT) compared to re-incision laparotomy (RL) (OR= 2.22, CI= 1.29-3.84, p <0.001). CONCLUSION: The strongest risk factor for uROR in trauma is compartment syndrome. Both a blunt (compared to penetrating) mechanism and RT (compared to RL) are independent risk factors for mortality in patients undergoing an uROR.

Perforated Peptic Ulcer Surgery: Decreased Length of Stay but No Difference in Mortality with Laparoscopic Repair.

BACKGROUND: Perforated peptic ulcer (PPU) surgery mortality ranges 1% to 24%. We hypothesized a decrease in length of stay (LOS) with laparoscopic surgical repair (LSR) compared with open surgical repair (OSR). METHODS: Patients undergoing PPU surgery 2005 to 2015 were identified in NSQIP. LSR was compared with OSR 2005 to 2015. LSR 2005 to 2010 was compared with 2011 to 2015. OSR 2005 to 2010 was compared with 2011 to 2015. The primary outcome was LOS. Secondary outcomes were mortality and morbidity. RESULTS: Between 2005 and 2015, LSR had a decreased LOS, was more likely to wean from the ventilator, but had no significant difference in mortality compared with OSR. There was no significant difference in mortality for LSR or OSR over time. CONCLUSIONS: When patients are appropriately selected, LSR for PPU is a viable alternative to OSR, decreasing LOS and pulmonary complications. This demonstrates significant benefit to patients and hospital throughput.

Rising mortality in patients with combined burn and trauma.

Combined trauma in the burn patient has been previously shown to have higher mortality. With improved critical care and multidisciplinary approach, we hypothesized the risk of mortality in combined burn and trauma has decreased. A retrospective analysis of trauma, burn and combined burn-trauma patients in the National Trauma Data Bank was performed comparing years 2007-2015 to years 1994-2002. The impact of burn injuries on mortality in patients with minor trauma has decreased (OR 2.45, CI 2.26-2.66, p<0.001 compared to OR 4.04, CI 4.51-4.66, p<0.001) in years 2007-2015 while the impact of burn injuries on mortality in patients with severe trauma has increased (OR 1.37, CI 1.29-1.47, p<0.001 compared to OR 1.26, CI 1.05-1.51, p<0.001). When controlling for known risk factors of mortality in burn and trauma, the contribution of the severity of trauma on mortality in combined burn-trauma patients with total body surface area ≥20% is negligible. In contrast, an increase in percentage of total body surface area burned is associated with a step-wise increase in mortality for all combined burn-trauma patients. However, the largest impact is seen in patients with minor trauma. This population represents a unique overlap of patients where future collaborative research can help identify best practices and improve outcomes.

How does blood loss relate to the extent of surgical wound excision?

PURPOSE: We investigated a novel system that uses image-processing algorithms to accurately measure the hemoglobin content of discarded surgical sponges to determine how blood loss relates to the excised area when current methods to minimize bleeding are employed. The system was used during 130 procedures in adult patients having wound excisions ≥1% BSA (study group). An historic group of 105 similar cases in whom visually estimated blood was determined was also evaluated. RESULTS: Surgical blood loss was less than previous estimates. The correlation between blood loss and the excised area in the study group was poor (R2=0.3988 for all patients and R2=0.1439 for excisions ≥10% BSA). Moreover, the visual estimates of blood loss in the historic group were more closely related to excised area than the accurate measurements in the study group (R2=0.6017 (historic), R2=0.3988 (study), p<0.001 for both). The mean absolute unstandardized residuals were 140.18±158.52 (historic) vs. 307.99±317.03 (study), p<0.001. CONCLUSIONS: As demonstrated in the historic group, visual estimates of blood loss tend to be more related to the size of excision than the amount of bleeding. The actual blood loss is not well correlated with the extent of excision. Clinicians should not rely on traditional blood loss estimates. Accurate measurement is needed to inform transfusion decisions and guide care.

Correcting for motion artifact in handheld laser speckle images.

Laser speckle imaging (LSI) is a wide-field optical technique that enables superficial blood flow quantification. LSI is normally performed in a mounted configuration to decrease the likelihood of motion artifact. However, mounted LSI systems are cumbersome and difficult to transport quickly in a clinical setting for which portability is essential in providing bedside patient care. To address this issue, we created a handheld LSI device using scientific grade components. To account for motion artifact of the LSI device used in a handheld setup, we incorporated a fiducial marker (FM) into our imaging protocol and determined the difference between highest and lowest speckle contrast values for the FM within each data set (Kbest and Kworst). The difference between Kbest and Kworst in mounted and handheld setups was 8% and 52%, respectively, thereby reinforcing the need for motion artifact quantification. When using a threshold FM speckle contrast value (KFM) to identify a subset of images with an acceptable level of motion artifact, mounted and handheld LSI measurements of speckle contrast of a flow region (KFLOW) in in vitro flow phantom experiments differed by 8%. Without the use of the FM, mounted and handheld KFLOW values differed by 20%. To further validate our handheld LSI device, we compared mounted and handheld data from an in vivo porcine burn model of superficial and full thickness burns. The speckle contrast within the burn region (KBURN) of the mounted and handheld LSI data differed by <4 % when accounting for motion artifact using the FM, which is less than the speckle contrast difference between superficial and full thickness burns. Collectively, our results suggest the potential of handheld LSI with an FM as a suitable alternative to mounted LSI, especially in challenging clinical settings with space limitations such as the intensive care unit.