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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.

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.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.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).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.

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).The Pediatric Trauma Quality Improvement Program (2014-2016) was queried for pediatric (age16 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.From 3693 bicyclists, 3039 (82.3%) were NHBs. Compared with HBs, NHBs were more often Black (21.6% vs 3.8%, P0.001), Hispanic (17.5% vs 9.3%, P0.001), 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%, P0.001). Both groups had similar rates of complications and mortality (P0.05). The associated risk of a serious head (odds ratio = 3.17, P0.001) 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 (P0.05).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.

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.

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, 3 cm 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 72 hours 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%) 24 hours after the burn. There was no statistically significant improvement from 24 to 72 hours 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.

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.

While visual clinical impression is the standard of care for burn severity assessment, accuracy improves after the injury progresses, leading to patients waiting days for a diagnosis. Spatial Frequency Domain Imaging (SFDI) has shown the potential to assess burn grade as early as 24 hours post-burn. Here, we compared SFDI and Laser Speckle Imaging (LSI) at 24 and 72 hours after burn injury to clinical burn severity diagnosis. Three patients with burns ranging in severity were imaged. Both techniques showed an ability to categorize burn severity 24 hours after the initial injury, well before the outcome was determined by a clinician at 72 hours or later.

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.

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. Keywords: Burns, Clinical, Humans, Spatial Frequency Domain Imaging, Laser Speckle Imaging

Spatial frequency domain imaging (SFDI), a noncontact imaging technique using structured illumination with multiple wavelengths, has proved feasible for characterizing burns of different severities induced in porcine dorsum. However, translation to human clinical subjects may be subject to variation in tissue optical properties due to different skin types or body parts. To interrogate this potential difference in optical properties, SFDI was used to measure the reduced scattering coefficient (μs’ ) in patients of varying Fitzpatrick skin type groups at 10 anatomical locations on the body. These scattering values were compared against previously measured average μs’ values for burns in a porcine model. At 851nm, superficial partialthickness burns had a 12.6% higher μs’ than unburned porcine dorsum. Deep partial-thickness and had 12.9% higher average μs’ than unburned porcine dorsum, while full-thickness burns had 2.5% higher average μs’ than unburned porcine dorsum. The variation seen in scattering values at 851nm at one anatomical location (dorsal forearm) for the different skin type groups showed a 6.3% lower average μs’ in group 3 (skin types VVI) compared to group 2 (skin types III-IV). Average scattering values were 3.8% lower in group 1 (skin types I-II) compared to group 2 (skin types III-IV). The variation of μs’ at 851nm across multiple anatomical locations for the same skin type group (Group 1) was a 23% difference from the anatomical location with the highest average μs’ at 851nm (forehead) to the lowest (shin). These findings indicate that further consideration of skin type and location will be integral to the translation of classification techniques based μs’ measurements of porcine dorsum to human patients.

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.

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

Background The role of preoperative clinics in improving surgical outcomes, reducing rate of surgical delays and case cancellations for patients undergoing outpatient elective surgery is well established. However, the impact of preoperative evaluation and risk assessment of inpatients undergoing surgery is less clear. We hypothesized that utilizing a standardized risk stratification method could reduce the rate of Same-Day Inpatient Cancellations (SDICs) in patients undergoing inpatient surgery. Methods This was a single center study conducted at an academic tertiary care hospital. An inpatient surgery form (ISF) that included a “risk stratification matrix” was completed for all inpatients undergoing non-emergent surgery. ISF was implemented at our institution over a three-year period (July 2014- March 2017). ISF stratified patients into “low,” “intermediate,” and “high” risk groups, which prompted hospitalist and anesthesia consultations based on the patient's risk category. We evaluated the difference in median SDIC rates during the four phases and differences in median proportions of SDICs attributable to Medical Related cancellations (MRCs) and Process-related cancellations (PRCs). Results Of 17,177 inpatient cases included for analysis, the average SDIC rate over the study was 9.5%. The Post-ISF SDIC rate was significantly less than the Pre-ISF SDIC rate (8.0% vs. 9.7%, p = 0.004). The proportion of MRCs during Post-ISF was also less than the Pre-ISF proportion of MRCs (47.1% vs. 60%, p = 0.02). Conclusion Standardized approach to preoperative risk stratification combined with timely pre-operative assessment and medical optimization of inpatients requiring surgery reduces the overall rate of inpatient surgical case cancellations.

Author(s): Ponticorvo, Adrien; Burmeister, David M; Rowland, Rebecca; Baldado, Melissa; Kennedy, Gordon T; Saager, Rolf; Bernal, Nicole; Choi, Bernard; Durkin, Anthony J | Abstract: The current standard for diagnosis of burn severity and subsequent wound healing is through clinical examination, which is highly subjective. Several new technologies are shifting focus to burn care in an attempt to help quantify not only burn depth but also the progress of healing. While accurate early assessment of partial thickness burns is critical for dictating the course of treatment, the ability to quantitatively monitor wound status over time is critical for understanding treatment efficacy. SFDI and LSI are both non-invasive imaging modalities that have been shown to have great diagnostic value for burn severity, but have yet to be tested over the course of wound healing.In this study, a hairless rat model (n = 6, 300-450 g) was used with a four pronged comb to create four identical partial thickness burns (superficial n = 3 and deep n = 3) that were used to monitor wound healing over a 28 days period. Weekly biopsies were taken for histological analysis to verify wound progression. Both SFDI and LSI were performed weekly to track the evolution of hemodynamic (blood flow and oxygen saturation) and structural (reduced scattering coefficient) properties for the burns.LSI showed significant changes in blood flow from baseline to 220% in superficial and 165% in deep burns by day 7. In superficial burns, blood flow returned to baseline levels by day 28, but not for deep burns where blood flow remained elevated. Smaller increases in blood flow were also observed in the surrounding tissue over the same time period. Oxygen saturation values measured with SFDI showed a progressive increase from baseline values of 66-74% in superficial burns and 72% in deep burns by day 28. Additionally, SFDI showed significant decreases in the reduced scattering coefficient shortly after the burns were created. The scattering coefficient progressively decreased in the wound area, but returned towards baseline conditions at the end of the 28 days period. Scattering changes in the surrounding tissue remained constant despite the presence of hemodynamic changes.Here, we show that LSI and SFDI are capable of monitoring changes in hemodynamic and scattering properties in burn wounds over a 28 days period. These results highlight the potential insights that can be gained by using non-invasive imaging technologies to study wound healing. Further development of these technologies could be revolutionary for wound monitoring and studying the efficacy of different treatments. Lasers Surg. Med. 49:293-304, 2017. © 2017 Wiley Periodicals, Inc.

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.

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.

More than half a million children experience non-accidental trauma (NAT) annually. Historically, NAT has been associated with an increased hospital length of stay (LOS). We hypothesized that in pediatric trauma patients, NAT is associated with longer hospital LOS, independent of injury severity, compared to accidental trauma (AT). The Pediatric Trauma Quality Improvement Program (2014–2016) was queried for patients aged 1–16 years. Patients were stratified into two groups: AT and NAT. The median LOS for the entire cohort was identified and used in a multivariable logistic regression analysis. From 93,089 pediatric trauma patients, 417 (

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.

While most superficial (first degree) burns and full thickness (third degree) burns are easily diagnosed through standard clinical inspection, burns that fall between these extremes are challenging to accurately classify based on clinical appearance alone. Accurate early assessments have the potential to enable earlier debridement and grafting, thereby reducing complication rates, healing times, and chances for infection. To this end, several emerging technologies aim to objectively and non-invasively quantify burn severity, including Spatial Frequency Domain Imaging (SFDI), Laser Speckle Imaging (LSI), and infrared thermal imaging (IR). While these imaging modalities have some diagnostic ability for in-vivo assessment of burn severity, they have not been directly compared in a controlled experiment. Here we compare the ability of these techniques to assess the severity of graded burns in a porcine model (n=96 burns, 6 pigs). Biopsies were taken for histological analysis to verify burn severity. Clinical assessment, SFDI, LSI and thermal imaging were performed for all graded burns at 24 and 72 hours post-burn. In terms of accuracy of burn severity assessment, using histology as a reference, SFDI (85%) and clinical analysis (83%) performed significantly better that LSI (75%) and thermography (73%) at the 24 hour post-burn time point. There was no statistically significant improvement in assessment accuracy at the 72 hour post-burn time point, across the imaging modalities. These data indicate that SFDI may provide valuable information to clinicians in future clinical trials. This information can be obtained early in the process, which may hasten surgical intervention and reduce complications.

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

Assessment of burn severity is critical for wound treatment. Spatial frequency domain imaging (SFDI) has been previously used to characterize burns based on the relationships between histology and tissue optical properties. Recently, multispectral and hyperspectral imaging optical features have been combined with machine learning to classify burn severity. Here, we investigated the use of SFDI reflectance data at multiple wavelengths and spatial frequencies, with a support vector machine (SVM), to predict severity in a porcine model of graded burns. Burn severity predictions using SVM were compared to burn grade determined using histology techniques. Results suggest that the combination of spatial frequency data with machine learning models has the potential for accurately predicting burn severity at the 24 hr postburn time point.

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 1000nm) 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, 24h 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.

Disparities in access to health care between white and minority patients are well described. We aimed to analyze the trends and outcomes of cholecystectomy based on racial classification. The Nationwide Inpatient Sample database was reviewed for all patients undergoing cholecystectomy from 2009 to 2012. Patients were stratified as white or non-white. A total of 243,536 patients were analyzed: 159,901 white and 83,635 non-white. Non-white patients had significantly higher proportions of Medicaid (25% vs 9.3%), self-pay (14% vs 7.1%), and no-charge (1.8% vs 0.64%). Non-white patients had significantly higher rates of emergent admission (84% vs 78%) compared with the white patients. Multivariate analysis revealed that non-whites had a significantly longer length of stay [mean difference of 0.14 days, 95% confidence interval (CI) 0.08–0.20] and higher total hospital charges (mean difference of $6748.00, 95% CI 5994.19–7501.81) than whites, despite a lower morbidity (odds ratio 0.94, 95% CI 0.90–0.98). Use of laparoscopy and mortality were not different. These differences persisted on subgroup analysis by insurance type. These findings suggest a gap in access to and outcomes of cholecystectomy in the minority population nationwide.

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 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.

Objective: To determine if accurate measurement of surgical blood loss using a novel device that photographs surgical sponges and calculates their hemoglobin content affects transfusion practice. Methods: We retrospectively compared transfusion events for patients having wound excisions using visual estimation of blood loss (traditional group; n=178) to similar events following device implementation (study group; n=221). Results: The study group (age 43 ± 22 years, body surface area burn 11.2 ± 18.0%, excision area 624, IQR 757 cm2, preoperative hemoglobin 10.7 ± 2.4 g/dl) did not differ significantly from the traditional group (age 42 ± 23 years (p=0.527), body surface area burn 12.2 ± 22.6% (p=0.661), excision area 753, IQR 505 cm2 (p=0.485), and preoperative hemoglobin 10.7 ± 2.2 g/dl (p=0.833). Postoperative transfusion rates were significantly lower in the study group (6.3% vs. 12.9%; p=0.024), as was the proportion of transfused patients undergoing multiple transfusion events (13.0% vs. 34.9%; p=0.01). Red cell dose (units/transfused patient) was less in the study group compared to the traditional group (1.83 ± 1.09 vs. 2.51 ± 1.61 units; p=0.021). In a subgroup of patients requiring excision of burned areas ≥ 1,000 cm2 (traditional group n=36, study group n=43), these differences were more significant. The postoperative transfusion rate fell from 44.4% to 14.0% (p=0.003), as did the percent of transfused patients experiencing multiple transfusion events (50.0% vs. 14.3%; p=0.004). Conclusions: Accurate measurement of surgical blood loss was associated with a decrease in transfusions suggesting more timely decision making. Informed transfusion decisions may result in fewer transfusions by avoiding over-transfusion related to both excessive hemodilution and inaccurate visual estimates.

Background: Restrictive red cell transfusion is preferable to liberal transfusion in most clinical situations. However, intraoperative transfusion decisions are challenging due to uncertainty about the amount and rate of bleeding, the poor correlation of haemoglobin levels with blood loss and the effects of anesthetics on blood volume and physiologic responses. Clinicians frequently use hemoglobin levels to guide transfusion. While these "triggers" assume that the patient is normovolemic, they are often applied in situations confounded by hemodilution or hemoconcentration. We postulated that accurate measurement of surgical blood loss would facilitate prediction of postoperative hemoglobin levels, potentially leading to more accurate intraoperative transfusion decisions. Methods: Using image-processing algorithms, a novel system accurately measures blood loss by photographing surgical sponges and canisters and calculating their hemoglobin content. A formula to predict postoperative hemoglobin levels was devised and used to calculate postoperative hemoglobin levels in a study group of 167 burn and other wound excision procedures performed on 103 patients using the system. In an historical group (100 similar procedures, 60 patients) clinician estimates of blood loss were used. These predictions were compared with actual values. Results: The formula using measured blood loss in the study group was a better predictor of the actual postoperative day one hemoglobin value (R2=0.822) than was the same formula using visually estimated blood loss used in the historical group (R2=0.615). The mean absolute bias of postoperative day one hemoglobin levels in the study group was significantly lower than the mean bias in the historical group (study=group, mean 0.4, 95% CI 0.2 to 0.5 g/dL; historical group, mean 0.9, 95% CI 0.7 to 1.2 g/dL, p

Computed tomography angiography (CTA) of the neck has become the most common modality for diagnosing blunt carotid artery injury (BCAI). The protocol at our institution includes CTA on trauma patients with a seatbelt sign. The purpose of this study is to evaluate whether a solitary seatbelt sign is an indication for CTA of the neck to diagnose BCAI. We conducted a retrospective review of patients from 2000 to 2010 who received CTAs as a result of a seatbelt sign performed at our Level I trauma center. Four hundred eighteen patients received CTAs based on the presence of a seatbelt sign. Two hundred twenty-six had skeletal injuries, obvious soft tissue injuries, and/or positive findings on imaging, including 11 positive vascular findings with two BCAIs found. Patients with noncarotid vascular injuries on CTA had a higher Injury Severity Score than patients with solitary seatbelt signs (11.4 ± 7.6 vs 3.4 ± 4.2, P < 0.01). The correlation between seatbelt sign and positive finding on CTA was weak ( r = 0.007). Patients with vascular findings on CTA also had obvious hard/soft tissue injuries and/or positive findings on standard trauma imaging. This suggests that a protocol for CTA of the neck for patients with a seatbelt sign can be reserved for those with associated injuries on physical examination and/or findings on standard trauma imaging.

Disparities in access to health care between white and minority patients are well described. We aimed to analyze the trends and outcomes of cholecystectomy based on racial classification. The Nationwide Inpatient Sample database was reviewed for all patients undergoing cholecystectomy from 2009 to 2012. Patients were stratified as white or non-white. A total of 243,536 patients were analyzed: 159,901 white and 83,635 non-white. Non-white patients had significantly higher proportions of Medicaid (25% vs 9.3%), self-pay (14% vs 7.1%), and no-charge (1.8% vs 0.64%). Non-white patients had significantly higher rates of emergent admission (84% vs 78%) compared with the white patients. Multivariate analysis revealed that non-whites had a significantly longer length of stay [mean difference of 0.14 days, 95% confidence interval (CI) 0.08-0.20] and higher total hospital charges (mean difference of $6748.00, 95% CI 5994.19-7501.81) than whites, despite a lower morbidity (odds ratio 0.94, 95% CI 0.90-0.98). Use of laparoscopy and mortality were not different. These differences persisted on subgroup analysis by insurance type. These findings suggest a gap in access to and outcomes of cholecystectomy in the minority population nationwide.

The magnitude of gut adaptation is a decisive factor in determining whether patients are able to live independent of parenteral nutrition after massive small bowel loss. We previously established that the cyclin-dependent kinase inhibitor (CDKI) p21waf1/cip1 is necessary for enterocyte proliferation and a normal adaptation response. In the present study, we have further elucidated the role of this CDKI in the context of p27kip1, another member of the Cip/Kip CDKI family. Small bowel resections (SBRs) or sham operations were performed in control (C57/BL6), p21waf1/cip1-null, p27kip1-null, and p21waf1/cip1/p27kip1 double-null mice. Morphological (villus height/crypt depth) alterations in the mucosa, the kinetics of enterocyte turnover (rates of enterocyte proliferation and apoptosis), and the protein expression of various cell cycle-regulatory proteins were recorded at various postoperative times. Enterocyte compartment-specific mRNA expression was investigated using laser capture microdissection. Resection-induced adaptation in control mice coincided with increased protein expression of p21waf1/cip1 and decreased p27kip1 within 3 days postoperatively. Identical changes in mRNA expression were detected in crypt but not in villus enterocytes. Adaptation occurred normally in control and p27kip1-null mice; however, mice deficient in both p21waf1/cip1 and p27kip1 failed to increase baseline rates of enterocyte proliferation and adaptation. The expression of p21waf1/cip1 protein and mRNA in the proliferative crypt compartment is necessary for resection-induced enterocyte proliferation and adaptation. The finding that deficient expression of p27kip1 does not affect adaptation suggests that these similar CDKI family members display distinctive cellular functions during the complex process of intestinal adaptation.

Background & Aims: Normal intestinal adaptation to massive small-bowel resection requires intact epidermal growth factor receptor signaling and consists of increased enterocyte proliferation and apoptosis. Although emphasis has been placed on understanding the regulation of proliferation, few studies have evaluated the mechanism and contribution of apoptosis to the adaptation response. We sought to test the hypothesis that epidermal growth factor receptor signaling regulates specific Bcl-2 family members (Bax and Bcl-w) to direct apoptosis and adaptation after massive small-bowel resection. Methods: Laser capture microdissection microscopy permitted measurement of Bax and Bcl-w messenger RNA expression in crypt and villus enterocytes in control conditions and under epidermal growth factor receptor–inhibited (waved-2 mice) or stimulated (epidermal growth factor transgenic mice) conditions after a 50% small-bowel resection or sham operation. Resection-induced adaptation was then studied in Bax-null and Bcl-w–null mice under control circumstances and after epidermal growth factor receptor stimulation. Results: When compared with Bcl-w, the most significant expression changes were observed with Bax and took place within crypt enterocytes. Epidermal growth factor receptor stimulation resulted in a decreased ratio of Bax to Bcl-w expression and decreased rates of apoptosis. Bax-null mice had no apoptosis response to small-bowel resection and displayed an amplified adaptation response to the administration of epidermal growth factor. Bcl-w–null mice had poor survival and impaired adaptation to small-bowel resection, an effect that was rescued by crossbreeding these mice with epidermal growth factor transgenic mice. Conclusions: The crypt expression of Bax and Bcl-w is influenced by epidermal growth factor receptor signaling and is key for the regulation of apoptosis. Epidermal growth factor receptor stimulation, coupled with apoptosis inhibition, may provide a novel strategy to amplify adaptation responses in patients after massive intestinal loss.

Background In the intestine, Wnt proteins are powerful regulators of cell proliferation, differentiation, and adhesion. Mutations of the adenomatous polyposis coli ( APC ) gene elevate nuclear β -catenin and provoke intestinal tumor formation. We sought to determine whether Wnt signaling is involved in adaptive response to massive small bowel resection (SBR). Methods Male Min mice with a mutation of the APC gene and wild-type controls underwent a 50% proximal SBR or sham operation. After 3 days, villus height, crypt depth, and rates of proliferation and apoptosis were recorded in the remnant ileum. Results After SBR, villus height and enterocyte proliferation were significantly greater in the Min mice. Western blotting demonstrated resection-induced increases in β -catenin, c-Myc, and E-cadherin after SBR, which was more pronounced in Min mice. Conclusions Mutation of the APC gene and augmented Wnt signaling in the intestine results in an enhanced adaptive response to massive SBR. These data, for the first time, implicate an important role for Wnt signaling during the pathogenesis of resection-induced intestinal adaptation.

Background Adaptation after massive smallbowel resection (SBR) is associated with increased cell turnover, increased rates of enterocyte proliferation, and apoptosis. Epidermal growth factor receptor (EGFR) inhibition attenuates adaptation and increases apoptosis. Intestinal levels of bax appear to correlate with EGFR signaling. This study tested the hypothesis that bax is required for the exaggerated postresection apoptosis induced by perturbed EGFR signaling. Methods Waved-2 mice with impaired EGFR signaling were crossbred with bax-null mice. Offspring were subjected to either 50% proximal SBR or sham operation (bowel transection and reanastomosis). After 7 days, parameters of adaptation (villus height, wet weight), proliferation (% Ki-67 immunostaining of crypt cells), and apoptosis (# apoptotic bodies per crypt) were recorded in the remnant ileum. Results Enterocyte apoptosis was increased in waved-2 mice and prevented in bax-null mice after SBR. The accelerated apoptosis in the waved-2 mice was rescued in the context of deficient bax expression. Other parameters of adaptation were restored in the bax-null/waved-2 mice. Conclusion Bax is required for the induction of postresection enterocyte apoptosis. Defective EGFR signaling augments resection-induced enterocyte apoptosis via a mechanism that also requires bax expression. These data implicate a link between EGFR signaling and bax in the genesis of postresection apoptosis and adaptation.

Background and Objective: Spatial Frequency Domain Imaging (SFDI) is a non-contact wide-field optical imaging technology currently being developed to investigate the feasibility of quantitative non-invasive evaluation of burn wound severity in a rat model. Our objective is to determine the potential of SFDI for mapping quantitative changes in spatially resolved tissue oxygen saturation and water concentration may be indicative of burn wound severity, healing, and further complications. In this portion of the investigation, we focus on the development of a rat burn model and the acute response of tissue to burn wounds. Study Design/Materials and Methods: A controlled burn protocol involving a heated brass comb was applied to 6 rats. Imaging was acquired at 17 evenly spaced wavelengths in the near-infrared from 650 to 970 nm. Over the course of the 3 hour post-burn period, we were able to map quantitative changes in spatially resolved chromophores. Burn severities were verified post-experiment using standard H and E histology and optical microscopy. Results/Conclusion: In total, we were able to induce 12 superficial-partial thickness burns, 8 deep-partial thickness burns, and 4 full thickness burns in our rat models. While several tissue chromophores were tracked, we found that changes in oxygen saturation and water concentration to be sensitive indicators of burn severity. Future work will include additional longitudinal studies over a period of days in order to investigate which parameters are correlated to tissue healing. © 2013 SPIE.

Objective To determine the outcomes effect of changing trends in patients with necrotizing acute soft tissue infections (NASTI) 2000–2008. Methods A single institution retrospective chart review of all patients treated for NASTI. Results There were 393 patients with mean age 50 years, diabetes 53%, % body surface area excised 3.5. Wounds were located on: extremity 57%, perineum 40%, trunk 26%. Wound cultures %: polymicrobial=62, Staphylococci=48, Streptococci=31. Patients developing complications %: Pulmonary=23, renal insufficiency/failure=27. During the study period, overall mortality rate remained unchanged: 30/393=7.6% (5.5% for patients first admitted by burn/trauma/acute care surgery vs. 29% for all other services, p =0.003). Significant annual increases were found in number of patients, p =0.03, male sex, p =0.000, transfer from outside hospital, p p =0.003, ventilator requirement >24h, p =0.0005, APACHE II p =0.002, and number of patients developing any complication, p =0.04. Statistically significant decreases annually were found in: days of antibiotic use, p =0.008, number of operations required for excision, p =0.02, development of non-wound infections, p =0.002, and length of stay in days (LOS), p =0.03. Conclusions This is the largest cohort of NASTI patients from a single institution to date, demonstrating significantly shorter LOS and decreased non-wound infection rates in the face of increasing BMI and APACHE II scores. The increasing number of patients and BMI suggests a causal relationship between NASTI and obesity. Initial care by surgeons experienced in caring for these patients provides mortality rates well below the national average.

Purpose Near-infrared spectroscopy has been used increasingly in the pediatric population as a continuous, noninvasive indicator of trends in organ perfusion and oxygenation. We studied healthy newborn babies to establish normal values during rest and feeding. Methods Forty-four term newborns were recruited. Near-infrared spectroscopy probes were placed on the forehead and over the right kidney to record cerebral (rSO 2 C) and renal-somatic (rSO 2 R) regional oxyhemoglobin saturation. Readings were collected continuously for 2 to 8 hours, spanning 1 to 3 feeding episodes. Results Data were available on 26 patients, with an average age of 44 ± 28 hours. The overall average rSO 2 C was 77.9% ± 8.5%, rSO 2 R was 86.8% ± 8.1%, and ΔrSO 2 RC (somatic-cerebral rSO 2 difference) was 8.9% ± 9.4%. During feeding, rSO 2 C was minimally decreased (78.6% ± 8.4% versus 78.0% ± 9.0%, P = .023), rSO 2 R did not change (87.0% ± 8.1% versus 87.3% ± 8.0%, P = .31), and ΔrSO 2 RC was minimally increased (8.5% ± 9.5% versus 9.2% ± 9.1%, P = .014). Over the first 120 hours after birth, average rSO 2 C decreased ( P 2 R remained relatively unchanged. Conclusions Clinical utility of near-infrared spectroscopy was partly limited by lack of normative data. These data demonstrate that regional oxygen extraction is greater across cerebral than across renal-somatic beds in normal newborns. Healthy newborns do not have clinically significant changes in organ oxygenation with feeding.

Background We have previously established the significance of epidermal growth factor receptor (EGFR) activity and the cyclin-dependent kinase inhibitor p21 waf1/cip1 (p21) for the adaptive response of the intestine to massive small bowel resection (SBR). In this study, we tested the role of the signal transducer and activator of transcription 1 (STAT-1) as this transcription factor is activated by the EGFR and known to induce p21 expression. Methods Control (n = 40; C57/Bl6) and STAT-1–null mice (n = 40) underwent 50% proximal SBR or sham operation. After 3 days, the remnant ileum was harvested and the villus and crypt morphology was measured along with changes in rates of enterocyte proliferation and apoptosis. Results The magnitude of resection-induced adaptation was greater in STAT-1–null animals as verified by taller villi and deeper crypts. The expected increase in enterocyte apoptosis did not occur after SBR in the background of STAT-1 deficiency. Western blotting revealed elevated expression of p21 protein in both STAT-1–null and controls after SBR. Conclusion Increased p21 expression after SBR in the absence of STAT-1 suggests an alternate mechanism for resection-induced regulation of p21. Enhanced adaptation in STAT-1–null animals suggests that this transcription factor serves an inhibitor to the process of adaptation, perhaps via regulation of enterocyte apoptosis.

Background Adaptation after massive small bowel resection (SBR) is associated with increased rates of enterocyte proliferation (P) and apoptosis (A). In the present study, we sought to determine the effect of dual therapy designed to increase P and simultaneously reduce A. Methods C57Bl/6 mice underwent a 50% small bowel resection (SBR) or sham operation, and then received an inhibitor of apoptosis (pan-caspase inhibitor), a stimulus for proliferation (epidermal growth factor; EGF), a combination, or vehicle control. After 3 days, adaptive morphology (villus height, crypt depth) and rates of enterocyte turnover (proliferation and apoptosis) were measured in the remnant ileum. Results Adaptation in controls and treated with the inhibitor was similar. EGF–treated mice demonstrated an even greater adaptive response. Combined therapy with the inhibitor and EGF resulted in maximal adaptation as gauged by the greatest increases in villus height and crypt depth and ratio of rates of P to A. Conclusion The capacity for adaptation following massive SBR is maintained via tight regulation of cell production and death. Pharmacologic intervention directed at increasing enterocyte proliferation while simultaneously decreasing apoptosis augments adaptation greater than either intervention alone and may provide a useful strategy to clinically amplify adaptation.

Background/Purpose Intestinal adaptation is a compensatory response to massive small bowel loss in which there are increased numbers of absorptive enterocytes. However, the generation of secretory epithelial cell subtypes in this process has not been investigated. The purpose of this study was to examine the adaptive changes of several small intestinal cell lineage changes in response to massive small bowel resection (SBR). Methods A 75% SBR or sham operation was performed on male Sprague-Dawley rats. On postoperative day 7, the remnant ileum was harvested and immunohistochemical staining for goblet, Paneth, and enteroendocrine cells was performed. Cell subtypes were evaluated as cells per micrometer of villus/crypt length and compared among operations. Results A significant increase in goblet cell density occurred after SBR. Intestinal resection did not alter the number of Paneth and enteroendocrine cells. In additional experiments, inhibition of epidermal growth factor receptor signaling was associated with a diminished goblet cell density. Conclusions The adaptive response of the intestine to massive bowel loss results in an expansion of the goblet cell population in addition to greater numbers of absorptive enterocytes. Although the mechanism and purpose for selective expansion of these stem cell–derived lineages are not presently known, epidermal growth factor receptor signaling appears to be a common pathway.

Background Originating from proliferating stem cells of the intestinal crypt, enterocytes differentiate as they migrate up the crypt-villus axis. A regulatory role of the cyclin-dependent kinase inhibitors p21 waf1/cip1 and p27 kip1 in these processes has been suggested by in vitro models. We sought to determine the effect of p21 waf1/cip1 and p27 kip1 deficiency on enterocyte differentiation, proliferation and migration. Methods Three strains of mice including control (C57Bl/6), p27 kip1 -null, and p21 waf1/cip1 -null were studied. Enterocyte differentiation was evaluated by immunostaining for intestinal alkaline phosphatase, by colorimetric assaying for intestinal alkaline phosphatase and sucrase enzyme activity, and by polymerase chain reaction for intestinal fatty acid–binding protein and villin-messenger RNA in enterocytes extracted by laser capture microdissection. Rates of enterocyte proliferation and migration were determined by 5-bromo 2-deoxyuridine immunostaining after a 50% small-bowel resection (SBR). Results Compared with controls, p27 kip1 –null mice demonstrated minimal differentiation but maintained a normal proliferative response to SBR. Contrarily, p21 waf1/cip1 -null mice demonstrated greater enterocyte differentiation without significant increases in enterocyte proliferation after SBR. Conclusions These findings suggest that p21 waf1/cip1 and p27 kip1 have distinctive and opposing roles in the pathogenesis of enterocyte differentiation, proliferation, and migration.

Frequent monitoring of early-stage burns is necessary for deciding optimal treatment and management. Both superficial and full thickness burns are relatively easy to diagnose based on clinical observation. In between these two extremes are superficial-partial thickness and deep-partial thickness burns. These burns, while visually similar, differ dramatically in terms of clinical treatment and are known to progress in severity over time. The objective of this study was to determine the potential of spatial frequency domain imaging (SFDI) for noninvasively mapping quantitative changes in chromophore and optical properties that may be an indicative of burn wound severity. A controlled protocol of graded burn severity was developed and applied to 17 rats. SFDI data was acquired at multiple near-infrared wavelengths over a course of 3 h. Burn severity was verified using hematoxylin and eosin histology. From this study, we found that changes in water concentration (edema), deoxygenated hemoglobin concentration, and optical scattering (tissue denaturation) to be statistically significant at differentiating superficial partial-thickness burns from deep-partial thickness burns. © 2013 SPIE.

Introduction. Following massive small bowel resection (SBR), there is an important adaptive response in the remnant ileum characterized by augmented enterocyte proliferation and apoptosis. This study tests the hypothesis that combined stimulation of enterocyte proliferation and inhibition of apoptosis would enhance adaptation to a greater extent than either perturbation alone. Methods. Bax-null mice in which postresection apoptosis is not induced and wild-type (WT) littermates underwent 50% proximal SBR or Sham operation (bowel transection with reanastomosis). Mice from both groups were then randomized to receive administration of epidermal growth factor (EGF) a stimulator of enterocyte proliferation or saline, which served as a control. Roughly 3–5 mice per group were studied. After 3 days alterations in morphology (villus height, crypt depth) and enterocyte turnover (proliferation − % uptake BrdU; apoptosis − # apoptotic bodies identified by TUNEL immunostaining) were measured. Results. Adaptation after SBR occurred normally in WT and bax-null mice. Treatment with EGF resulted in an expected greater adaptation response in the WT mice. In bax-null mice EGF amplified the adaptation response even further (Figure). Conclusion. The magnitude of resection-induced adaptation is dependent upon a tight balance between rates of enterocyte proliferation and apoptosis. This study suggests that a dual therapeutic strategy directed at increasing enterocyte proliferation coupled with preventing apoptosis is better than either approach alone. These findings offer a new treatment paradigm as a means to encourage a maximal adaptation response following the acute loss of significant intestinal length. Download full-size image