Retrospective Review of Outcomes Related to Early Therapy Intervention Following Application of Cultured Epidermal Autografts in Severely Burned Patients

Cultured epidermal autografts (CEA) have since become more prevalent in the treatment of burn-injured patients with limited available donor sites for adequate wound closure, resulting in decreased mortality rates and an increased number of these patients requiring burn therapy services to achieve optimal functional outcomes at discharge. However, the use and postoperative management of CEA continues to be controversial due in large to the physiological fragility and expense of CEA, leading to variable postoperative treatment practices across burn centers. As such, minimal research is available regarding patient outcomes following CEA application, specifically related to burn therapy intervention. Thus, a retrospective chart review was conducted on a series of 10 patients, 18 years of age or older, admitted to a single, American Burn Association (ABA) verified burn center, between April 2015 and April 2023, who required CEA, and received pre- and postoperative treatment by burn therapists in accordance with center-specific burn rehabilitation guidelines. The resulting patient outcomes, in response to early implementation of therapy interventions post-CEA surgery, demonstrated optimal functional status for patients upon discharge, and positive long-term implications.

Inhalation Injury, Respiratory Failure, and Ventilator Support in Acute Burn Care

Sustaining an inhalation injury increases the risk of severe complications and mortality. Current evidential support to guide treatment of the injury or subsequent complications is lacking, as studies either exclude inhalation injury or design limit inferences that can be made. Conventional ventilator modes are most commonly used, but there is no consensus on optimal strategies. Settings should be customized to patient tolerance and response. Data for pharmacotherapy adjunctive treatments are limited.

Pharmacokinetic Analysis of Intravenous Push Cefepime in Burn Patients with Augmented Renal Clearance

Patients with augmented renal clearance (ARC) are a subset of critically ill patients including burn patients that exhibit increased renal elimination of medications beyond that of similarly injured patients. Currently approved maximum regimens of medications primarily eliminated by the kidney, such as cefepime (>90% unchanged in the urine), may be inadequate (eg, compromising the bactericidal activity of cefepime) in patients with ARC. Due to recent resource limitations, centers have changed infusion practices of commonly prescribed medications to intravenous push (IVP), potentially exacerbating the problem of maintaining bactericidal cefepime concentrations. The hypothesis of the study was patients with ARC are not currently achieving adequate target attainment, when receiving cefepime 2 g every 8 h IVP. Eight blood samples were collected from each patient, and concentrations measured via LC-MS/MS. WinNonlin (version 8.3) was used to estimate the pharmacokinetic parameters of cefepime and simulate plasma concentrations of cefepime in each of the ten subjects. Simulations of cefepime plasma concentrations produced by a 2 g dose given every 8 h and a 1 g dose given every 4 h were performed and the time above a MIC of 4 mg/L, 8 mg/L, and 16 mg/L compared. The 2 g every 8 h regimen remained above the breakpoints for 92%, 85%, and 71% of the dosing interval, respectively. The 1 g every 4 h regimen remained above the same breakpoints at a frequency of 100%, 99%, and 92% of the dosing interval. Giving cefepime 1 g every 4 h is a simple approach to increase the likelihood of maintaining the optimal bactericidal activity of cefepime in patients with ARC.

A Regional Analysis of Potentially Preventable Injuries Sustained From Burning Garbage and Yard Waste

Due to high prevalence in the south, understanding the injury pattern, healthcare burden, and cost of burn injuries associated with burning yard and trash debris are important for effective prevention. This 5-year retrospective, single-center study included patients sustaining an open flame burn injury due to burning brush or trash. Based on primary residence of the 136 patients, 56% had access to free municipal waste disposal, 25% could have had access with additional payment, and 18% did not have access. The median (Q1 and Q3) age and total body surface area (TBSA) burned was 50 (32, 66.5) years and 5% (2.5, 12), respectively, with 36% having some portion of full-thickness injury. One-third had some form of substance use. There were 151 total operations with a median of 1 (0, 1.5) per patient. There were 1,620 hospital days utilized (~6.6% of available bed-days per study period). Twenty-five percent were discharged with a paired functional status worse than pre-injury. Patients with some degree of pre-injury function limitations had a 3-fold higher length of stay (10 vs 3 days; P = .023). Patients with lower pre-injury functionality had almost four times higher mortality (23.7% vs 6.3%; P = .085). There were 9 (6.7%) deaths with an average (±SD) of 74.3 ± 13.1 years of age, median of 33% (31, 43) TBSA, and median full-thickness TBSA of 32% (21, 44). Total hospital charges exceeded $32.6 million with a median of $32,952.26 ($8,790.48, $103,113.95) per patient. Focusing future outreach efforts on education and resource availability may prevent future waste-burning injuries.

A Retrospective Chart Review to Determine Hypophosphatemia Incidence and Phosphorus Supplementation Requirements in Patients With Severe Thermal Cutaneous Injuries Receiving High-Volume Hemofiltration

Patients with severe thermal injuries have increased metabolic demands necessitating frequent phosphate supplementation. Patients with acute renal failure may have less requirements, due to reduced elimination. However, patients being supported with renal replacement therapy have varying degree of requirements. Little published evidence depicts the incidence of hypophosphatemia and repletion requirements in patients with severe thermal injuries treated with high-volume hemofiltration (HVHF) and a high-flux membrane. The objective of this retrospective chart review was to determine the incidence of hypophosphatemia and characterize repletion requirements and response in this population. Enrolled patients had at least 20% TBSA thermal injuries and required continuous hemofiltration with prefilter replacement fluid doses ≥35 mL/kg IBW/hr. A randomly selected cohort without acute kidney injury (AKI) and matched based on age and extent of TBSA was used to compare phosphorus requirements over an initial 14-day period. Demographics, diet, and variables affecting phosphorus concentrations were collected. Sixteen patients were included in the retrospective HVHF group and 16 patients in a case-control cohort to better depict the impact of HVHF. The average age was 60.2 ± 15.1 years and median TBSA was 30% (23.4, 56.3) in the HVHF group, compared to 53.3 ± 16.4 years (P = .22) and TBSA 29% (26.4, 33.9; P = .73). All patients in the HVHF group were started on HVHF with a 1.6 m2 polyethersulfone membrane for AKI. As expected, the HVHF group exhibited statistically higher than normal baseline potassium and phosphorous laboratory values. The HVHF group experienced more days with hypophosphatemia (49.6 ± 12.4% vs 29.3 ± 16.3%, P = .012), despite 0.75 mmol/kg/day phosphorous supplementation (compared to 0.66 mmol/kg/day for the control group, P = .45). Patients with longer durations of HVHF therapy experienced increasing risk of hypophosphatemia, reaching 100% by the end of the study period. This study demonstrates severe thermally injured patients receiving HVHF for AKI are at increased risk for hypophosphatemia, and require high phosphate supplementation.

Efficacy of a Novel LAM Femoral Cutaneous Block Technique for Acute Donor Site Pain

Patients with severe burn injuries often require split-thickness skin grafting to expedite wound healing with the thigh being a common donor site. Uncontrolled pain is associated with increased opioid consumption, longer lengths of stay, and delay in functional recovery. Peripheral nerve blocks are increasing in popularity although supportive literature is limited, and techniques vary. The purpose of this case series is to assess the safety, feasibility, and clinical efficacy of a recently demonstrated novel continuous LAM (lateral, anterior, medial) femoral cutaneous block technique in a larger cohort. The study was a dual IRB approved, observational case series from a single verified burn center. The electronic health record was retrospectively reviewed for patients admitted between June 2018 and May 2021 who had the continuous LAM block performed for donor site pain by the acute pain service team. Demographics were reported with descriptive statistics and morphine milligram equivalents (MME) were analyzed via Friedman analysis of variance. Forty-seven patients had a total of 53 blocks placed, where 2 patients received the LAM block on two separate occasions and 4 patients had bilateral LAM blocks placed. Most were African-American males, but mechanism of injury varied. Over half had a neurologic (17%) or psychiatric history (34%) outside of substance use. Almost three-quarters had a history of substance use with 17% being opioids, and a quarter had a history of polysubstance use. Median day from admission to LAM was 7 (2.5, 11.5) with a median duration of 4 (3, 5) days. Temperature and pressure sensation were reduced at the donor site. Quadricep strength remained intact, and median day until first ambulation after LAM placement was 2 (1, 3) days. Pain was adequately controlled, and there were no significant adverse events associated with the block. There was a significant reduction in MME after block placement (p < .001). Continuous peripheral nerve blocks offer an advantageous means of analgesia, while reducing potential adverse events associated with opioids or multimodal regimens. The novel LAM technique reduced sensation and pain without inhibiting early ambulation, and patients were able to fully participate in their rehabilitation.

A Randomized Trial of Enteral Glutamine for Treatment of Burn Injuries

BACKGROUND

Glutamine is thought to have beneficial effects on the metabolic and stress response to severe injury. Clinical trials involving patients with burns and other critically ill patients have shown conflicting results regarding the benefits and risks of glutamine supplementation.

METHODS

In a double-blind, randomized, placebo-controlled trial, we assigned patients with deep second- or third-degree burns (affecting ≥10% to ≥20% of total body-surface area, depending on age) within 72 hours after hospital admission to receive 0.5 g per kilogram of body weight per day of enterally delivered glutamine or placebo. Trial agents were given every 4 hours through a feeding tube or three or four times a day by mouth until 7 days after the last skin grafting procedure, discharge from the acute care unit, or 3 months after admission, whichever came first. The primary outcome was the time to discharge alive from the hospital, with data censored at 90 days. We calculated subdistribution hazard ratios for discharge alive, which took into account death as a competing risk.

RESULTS

A total of 1209 patients with severe burns (mean burn size, 33% of total body-surface area) underwent randomization, and 1200 were included in the analysis (596 patients in the glutamine group and 604 in the placebo group). The median time to discharge alive from the hospital was 40 days (interquartile range, 24 to 87) in the glutamine group and 38 days (interquartile range, 22 to 75) in the placebo group (subdistribution hazard ratio for discharge alive, 0.91; 95% confidence interval [CI], 0.80 to 1.04; P = 0.17). Mortality at 6 months was 17.2% in the glutamine group and 16.2% in the placebo group (hazard ratio for death, 1.06; 95% CI, 0.80 to 1.41). No substantial between-group differences in serious adverse events were observed.

CONCLUSIONS

In patients with severe burns, supplemental glutamine did not reduce the time to discharge alive from the hospital. (Funded by the U.S. Department of Defense and the Canadian Institutes of Health Research; RE-ENERGIZE ClinicalTrials.gov number, NCT00985205.).

Analysis of Ceftazidime/Avibactam Use for Treating Carbapenem-Resistant Infections in Critically Ill Patients With Thermal or Inhalation Injuries

Rising antimicrobial resistance is a pressing public health concern. An increase in carbapenem-resistant organisms has led to increased use of novel antibiotics, such as ceftazidime/avibactam (CZ/AV). However, recent studies have shown increasing treatment failures and resistance rates associated with ceftazidime/avibactam use. The efficacy of CZ/AV has not been studied in patients with thermal or inhalation injuries, where pharmacokinetic derangements are common and patients are often subject to longer lengths of stay and several antimicrobial courses that may lead to higher resistance rates. The objective of this study was to evaluate the outcomes of patients with thermal and inhalation injuries including clinical success, the frequency of adverse effects, and emergence of resistance. In the 17 courses of CZ/AV evaluated, clinical success occurred in 71% (12/17) of courses. Enterobacter cloacae was the most commonly treated pathogen. Resistance developed in 18% (3/17) of courses, but follow-up sensitivities were not evaluable for every case. Although lower than desired, clinical success rates in this sample were similar to other reported populations treated with CZ/AV. However, the emergence of resistance occurred more frequently and was likely underreported in this sample. Although limited by its small sample size, this study emphasizes the concern of growing antimicrobial resistance among even novel antibiotics. Resistance can develop during the initial course, stressing the importance of infection prevention and antimicrobial stewardship. Furthermore, attention and resources should be given to proper pharmacokinetic analysis of medications given in severely ill, hypermetabolic populations.

72 Burn Rehabilitation Non-invasive Approach; Lower Extremity Burns

Introduction

An increase intolerance to weight-bearing or ambulation was noted when second degree burns were sustained in the lower extremities, specifically knee distally. Patients were noted to request additional pain medication and/or additional time in the bed, which are not this burn center’s burn rehabilitation activity protocol.

Use of double ace wraps, from knee distally, was initiated to increase patient’s participation in burn rehabilitation therapy. A retrospective chart review was used to determine if there were similar factors could be identified to anticipate use of a lower extremity double ace wrap.

Methods

Retrospective chart review from July 2020 to August 2021 was performed to identify lower extremity burns. Inclusion criteria included: age 13 or greater; admitted to this burn center w/LOS greater than 24 hours, received burn rehabilitation therapy; second and third degree burns located below the knee; and pre-admission status of independent ambulator.

Chart review included 104 patients, with criteria met by 19 males and 5 females. The average age was 38.9 years with a range of 13 to 78 years. Length of stay ranged from 1 to 30 days and pre-exiting medical history included diabetes, type II in 8.3% and hypertension in 16.7% of the patients.

The TBSA ranged from 1.15% to 42%. Surgical procedures of BWE w/dermal/epidermal skin substitute application from knee distally, occurred in 50% of the patients; 37.5% underwent BWE w/allograft and within 5-7 days underwent meshed split thickness skin grafts; 4% underwent BWE with placement of xeroform. 8.3% did not require surgery.

Results

All patients involved in the study required use of double ace wraps during hospital stay. Duration of use of double ace wraps depended on subjective report of abnormal sensations. Use was required mainly in the acute phase of burn injury prior to autografting, in partial thickness burns that underwent surgical procedure for application of dermal/epidermal skin substitute, or in patients that did not require autografting.

Patient’s verbalizations of abnormal sensations with attempts to immediately weight bear or ambulate included: shooting pain, stinging pain, throbbing sensation, pins and needles. Reports of abnormal sensations and increased compliance with burn rehabilitation therapy was noted immediately following application of double ace wrap.

Conclusions

Burn Rehabilitation therapy protocol now includes close identification of superficial or deep second degrees located distally to the knee and patient’s verbal descriptions of abnormal sensations with attempts to place feet into a dependent position. Burn Rehabilitation therapy has developed a wearing schedule of the double ace wrap which has resulted in no adverse effects and positive patient compliance and participation.

516 Phosphorus Requirements in Patients with Severe Thermal Injuries Requiring High-Volume Hemofiltration

Introduction

Patients with thermal injuries have increased metabolic demands, requiring increased phosphate supplementation. Evidence is scant depicting incidence of hypophosphatemia and repletion requirements in patients with thermal injuries treated with high-volume hemofiltration (HVHF) and a high-flux membrane. The objective of this study was to determine the incidence of hypophosphatemia and characterize repletion requirements in this population.

Methods

This study was a case-control, retrospective chart review. Patients were included if sustained at least 20% total body surface area (TBSA) thermal injuries and required continuous HVHF (prescribed doses ≥ 35 mL/kg/hr). A randomly selected cohort (matched to age, TBSA, and inhalation injury) without acute kidney injury (AKI) was used to compare phosphorus requirements over an initial 14 day period. An a priori sample size was calculated (n = 26) to detect a minimum difference of 0.3 mmol/kg/day. Repeated measures ANOVA was used to compare requirements and concentrations. Demographics, diet, and variables affecting phosphorus concentrations were compared utilizing Fisher's exact, Student's t-test, or Mann-Whitney test depending on type and distribution.

Results

One thousand sixty-six patients were screened. Most were excluded from the HVHF group for TBSA < 20% (58%) or not a burn injury (29%). Sixteen patients were included in each group. The average age was 60.2 ± 15.1 vs 53.3 ± 16.4 (p = 0.22) with median TBSA (p = 0.73) of 30% (23.4, 56.3) vs 29% (26.4, 33.9). All patients in the study group were started on HVHF for AKI, utilizing a 1.6m² polyethersulfone membrane (mean delivered prefilter dose of 54.7 ± 1.5 ml/kg/hr), and had statistically higher potassium and phosphorous laboratory values at baseline. Parenteral phosphorus replacements were 2 fold higher in the HVHF group (p = 0.02), but not statistically different after accounting for estimated enteral intake. Despite providing 0.75 mmol/kg/day of phosphorous supplementation (vs 0.66 mmol/kg/day in control, p = 0.45), the HVHF group experienced more days with hypophosphatemia (49.6 ± 12.4 % vs 29.3 ± 16.3 %, p = 0.012). By 72h, every HVHF patient experienced at least one episode of hypophosphatemia. Patients on longer durations of therapy had increasing risk of hypophosphatemia. There was a significant difference in days requiring mechanical ventilation (p < 0.001)

Conclusions

This study demonstrates thermally injured patients receiving HVHF for AKI are at increased risk for hypophosphatemia and require higher phosphate supplementation to maintain lower average serum concentrations, as compared to the controls with similar burns but without acute kidney injury.

704 Ceftazidime / Avibactam Efficacy for Treating Carbapenem-resistant Infections in Critically Ill Patients with Thermal Injuries

Introduction

Rising antimicrobial resistance is a pressing public health concern. Emergence of carbapenem-resistant organisms has led to increased use of novel antibiotics, such as ceftazidime/avibactam (CZ/AV). However, recent studies have shown increasing treatment failures and resistance rates associated with ceftazidime/avibactam use. The efficacy of CZ/AV has not been studied in patients with thermal injuries, where pharmacokinetic derangements are common and longer lengths of stay augment risk of requiring several antimicrobial courses, leading to higher resistance rates. The objective of this study was to evaluate the outcomes of patients with thermal injuries including clinical success, the frequency of adverse effects, and emergence of resistance.

Methods

The design was a retrospective chart review. Patients were included if admitted with thermal injuries and receiving at least 48 hours of CZ/AV between Jan. 1, 2017 and July 2020. Demographics and treatment data were reported using descriptive statistics. Treatment success, description of treatment failures, and adverse events were described. Logistic regression was used to control and analyze failures.

Results

Fifteen patients with 17 courses evaluated. Most were male (87 %) and African American (53 %). The mean age and weight was 47.7 ±13.6 and 96.3 ± 29.4. Seventy-three percent had a flame injury. Mean TBSA was 34 ± 18.7. Twenty percent had an inhalation injury and 80 % a significant substance use history. Clinical success occurred in 65% (11/17) although 29% died. E. cloacae (88%) was the most common treated pathogen, but 81% were polymicrobial. The most common sources were wounds (29%), blood (29%), and lungs (26%). Median days until CZ/AV initiation was 32 (14,76). CZ/AV was dosed at 2.5 g every 8 hours in all courses. Median treatment duration was 12 days (9,14). Fifty-three percent received CVVH with a mean delivered dose of 47.6 ± 9.5 ml/kg/hr. Resistance developed in 19% (3/17) of courses, but follow up sensitivities were rarely available. Logistic regression did not reveal any variables significantly associated with failure. There were no adverse events attributed to CA/AV

Conclusions

Although lower than desired, clinical success rates in this sample were similar to other reported populations treated with CZ/AV. However, the emergence of resistance occurred more frequently, and was likely underreported in this sample. HVHF did not contribute to failure, but CZ/AV was aggressively dosed in this cohort.

515 Deficiencies of Rule-based Technology generated Antibiograms and Application in Patients with Prolonged Lengths of Stay

Introduction

Antibiograms are unit specific annual reports of cumulative pathogen incidence and antibiotic susceptibilities, used to guide selection of empiric antibiotic therapies. Rule-based technology (RBT) expedites data compilation, but follows “first pathogen, per patient” and limits applicability, especially for prescribing antibiotics in units with higher lengths of stay. The objective was to compare the pathogens and susceptibilities of the current automated RBT antibiogram with one manually collected through chart review with additional rules applied.

Methods

This is a single-center, retrospective cohort study utilizing chart review to assess patients admitted to the Burn Center between January 2018 and December 2019 from whom significant bacterial cultures were obtained. Demographics and burn injury characteristics were collected. Treatment data related to the infection and antibiotic usage was also collected. Specific to the culture, timing, site, pathogen, and sensitivity were collected. All cultures within the first 30 days of admission were included. The current RBT antibiogram served as the control. And new antibiogram versions were created using additional rules and compared to the RBT antibiogram.

Results

During the 2 years, 657 patients were admitted. Two-hundred four patients remained after applicable exclusions. Sixty-one percent were excluded due to lack of cultures. Mean age was 50.6 ± 16.5 years and 66% were male. Forty-nine percent were Caucasian. Seventy-two percent were admitted for an acute burn injury with flame as the primary mechanism and a median percent total body surface area of 10 (3, 21). Fifty-nine percent had at least one hospital acquired risk factor with over one-third having recent illicit drug use and one-third having a recent hospitalization. Of the 410 cultures included, 57% were Gram-negative and half were from wound infections. Sensitivities were significantly different when comparing the RBT to those created from significant cultures within 7 days of admission, cultures within 7 days of admission and without hospital-acquired infection risk factors (Figure 1), and those being treated with an initial or subsequent course of antibiotics. Recommended empiric antibiotic changed from double coverage to a single β-lactam with > 90% susceptibility. The susceptibilities between first and subsequent courses were dramatically different (Figure 2)

Conclusions

The antibiogram was significantly different from the RBT version after including factors, such as days since admission, presence of hospital acquired risk factors, or previous antibiotic courses. Before developing an antibiogram or interpreting the output, it is important to consider which automated criteria are utilized, especially for units with extended lengths of stay.

29 Efficacy of a Novel LAM Femoral Cutaneous Block Technique for Acute Donor Site Pain

Introduction

Patients with severe burn injuries often require split thickness skin grafting to expedite would healing with the thigh being a common donor site. Uncontrolled pain is associated with increased opioid consumption, longer lengths of stay, and delay in functional recovery. Regional nerve blocks are increasing in popularity although supportive literature is limited, and techniques vary. Recently, we presented a case demonstrating a novel LAM (lateral, anterior, medial) femoral cutaneous block technique. The purpose of the case series is to assess the safety, feasibility, and clinical efficacy in a larger cohort.

Methods

The study was a dual IRB approved, observational case series from a single verified burn center. The electronic health record was retrospectively reviewed for patients admitted between June 2018 to June 2020 who had the LAM block placed for donor site pain by the acute pain service (APS) team. Patient demographics, and data pertinent to the LAM regional anesthesia block were collected (eg opioid usage before and after the block, pain, and physical therapy outcomes). The data were tabulated and analyzed using Microsoft Excel© and SPSS version 27.0. Descriptive statistics were utilized to describe the patient demographics and LAM block feasibility & safety. Morphine Milligram Equivalent (MME) were statistically compared utilizing repeated measures ANOVA on ranks and graphically presented.

Results

Twenty-four patients had total of 27 blocks placed, where 3 patients received the LAM block on two separate occasions. One patient had bilateral LAM blocks placed and was included as the single instance for the analysis. The majority were Caucasian males, but mechanism of injury varied. Two-thirds had a neurologic or psychiatric history. Seventy-one percent used tobacco and a quarter had a history of polysubstance abuse. Median area of the donor site was 360 cm2 (207, 1140). Median day from admission to LAM was 8 (3, 12) with a median duration of 4 (3, 5) days. Median day until first ambulation after LAM was 3 (1,3). Eighty percent reported a decreased temperature sensation at the donor site. Pain was adequately controlled, and there were no adverse events or quadricep weakness noted. There was a significant reduction in MME after block placement (Figure 1).

Conclusions

Regional nerve blocks offer an advantageous means of analgesia, while reducing potential adverse events associated with opioids. While the novel LAM technique reduced some sensation, early ambulation was not inhibited and patients able to participate with rehabilitation therapy.

Chemical Burns from Secondary Exposure to Paraquat Through Mishandling Urine of a Patient with Toxic Exposure

Paraquat is used throughout the world as an herbicide due to efficacy and relative safety with proper handling. Accidents and misuse still occur, leading to countries banning its use or employing extra safeguards and special handling certifications. Severe toxicity is primarily associated with ingestion, but skin exposure leads to corrosive injury to the dermis, occurs rapidly, and progresses for up to 24 hours. Prolonged skin exposure or the presence of open wounds can lead to systemic absorption. This is the first known report of burn injury and treatment due to secondary exposure to the urine of a patient who had accidental ingestion of paraquat. A 50-year-old Caucasian male presented to the emergency room after accidental ingestion of eight ounces of Gramoxone extra (Paraquat 30% concentration). During initial care of the patient, the bedside registered nurse was placing an indwelling foley catheter when her forearms were contaminated with urine, while wearing basic personal protective equipment (gloves). The registered nurse noticed bullae to bilateral forearms a short time after exposure to the urine. She presented to the burn center for evaluation and treatment. Poison Control was contacted but was unable to offer advise due to lack of supportive literature. The risk and effects of primary exposure to Paraquat is described throughout the literature and documented in MSDS, but data regarding risk and treatment of secondary exposure is lacking. This case will aid outreach efforts for prevention and treatment of burn injuries from secondary exposure to paraquat.

Esterified Hyaluronic Acid Matrix in Lower Extremity Reconstruction With Exposed Tendon and Bone: A Retrospective Review

Lower extremity wounds with exposed bone and tendon often need coverage to allow the underlying tissue to regenerate prior to skin graft. The surgeon is limited in his or her choices to augment tissue regeneration in these types of complicated cases; for instance, autologous skin should not be placed on exposed bone or tendon and is at risk for contracture when placed over the joints. Therefore, novel technologies are necessary to provide a scaffolding for tissue to regenerate and allow for a successful graft. One such technology is an esterified hyaluronic acid matrix (eHAM), which can provide a proper scaffold for endothelial cell migration and aid in angiogenesis. The eHAM is made of two layers: a layer of hyaluronic acid covered with a silicone layer. In this retrospective chart review, we describe our usage of eHAM to provide scaffolding for tissue regeneration prior to grafting in 15 cases of complicated lower extremity wounds with exposed bone and tendon. The average patient age was 45.8 years, and all patients had multiple medical comorbidities, such as poorly controlled diabetes mellitus, hypertension, and nicotine addiction. Patient wound types were diverse, including traumatic wounds, chronic diabetic foot ulcers, and thermal or electric burns. Thirteen of the 15 cases were treated successfully with eHAM. In these cases, definitive coverage with split-thickness skin grafting was effective and limb salvage was successful. In the 13 successful cases, the mean time to split-thickness skin graft was 22.9 ± 7.0 days. All patients continue to do well at follow-up (ranging from 6 to 48 weeks), with minimal complications reported. Given the success rate with eHAM in this challenging population, we conclude that eHAM can be a treatment option for similar cases.

Simplified Approach to Incorporating Glycemic Response Within a Continuous Insulin Infusion Algorithm to Improve the Incidence of Hypoglycemia in a Single Burn Center

Attaining adequate glycemic control in burn patients has been shown to reduce infection-related mortality. Previous internal evaluation of continuous insulin infusion (CII) use revealed a hypoglycemia rate of 0.6% and an average time within goal glycemic range (70–149 mg/dl) of 13.8 h/day. A new algorithm, designed to adjust dosage based on glycemic response, underwent six iterations over 2 years before the final version was implemented. The purpose of this retrospective study was to assess the post-implementation performance of the newly developed CII algorithm. The current study was powered to detect a 50% reduction in hypoglycemic events, as compared to a pre-implementation historical control. The cohort was 62% male with a mean age of 54.5 ± 17.4. Sixty-five percent had thermal injuries with a median 23.5 (11–45) %TBSA. There were no differences in demographics between groups. Among the 20 records reviewed, 5239 point-of-care glucose values were assessed. Post-implementation, hypoglycemia rates were significantly lower (0.6% vs 0.2%; P &lt; .001). There was no difference in median blood glucose between groups (149.9 vs 146.5 mg/dl; P = .56). Time spent within goal glycemic range was not significantly different (13.8 vs 14.7 h/day; P = 0.23). There were no differences in infection, length of stay, or survival. The consolidation, education, and implementation of a single, dynamic CII algorithm reduced the incidence of hypoglycemia. The authors expect that education and diligence with follow-up glucose monitoring will further improve time within goal glycemic range by preventing rebound hyperglycemia.

Heterotopic ossification: a preventable case of gossypiboma in spinal cord injury

OBJECTIVE

Heterotopic ossification is the formation of ectopic bone in soft tissues. It has three established aetiologies: genetic, traumatic and neurogenic. A gossypiboma is defined as a retained foreign body, such as a mass or sponge, usually after a surgical procedure. In this article, we present a unique, preventable case of a patient admitted for newly developed heterotopic ossification in the gluteus maximus muscle caused by a retained piece of foam from negative pressure wound therapy (NPWT). The heterotopic ossification lesion, together with the retained foreign body, was completely excised and reconstructed using a posterior thigh fasciocutaneous advancement flap. This is the first reported case of heterotopic ossification caused by a retained foreign body and may be helpful to better understanding of the aetiology of heterotopic ossification.

Analysis of factors impacting length of stay in thermal and inhalation injury

OBJECTIVES

Several studies have analyzed single or combinations of variables for impact on length of stay (LOS) in thermally-injured patients. The objective of this study was to evaluate a multitude of established variables and potentially identify novel variables associated with LOS in a single study.

METHODS

This two-year, retrospective study included all patients admitted to the burn center between January 2015 and December 2016. Exclusions included death during admission, lack of thermal or inhalation injury, age less than 18 years, readmission(s), and if pregnant or incarcerated. Baseline demographics and pertinent data were collected using electronic medical records. Regression analysis was used to determine the most predictive variables.

RESULTS

Six hundred twenty-nine patients were admitted during the inclusion period and 354 patients remained for analysis after exclusion. Univariable analysis revealed 32 variables significantly associated with LOS. Using multivariable regression, the best-fit baseline demographic model included: percent total body surface area (TBSA) injured, lower/middle socioeconomic status, clotting disorders, anemia, admission serum creatinine, and percent third degree injured (r² = 0.557). The best-fit combined model (incorporating baseline demographics and early in-hospital variables) included: acute kidney injury, infection and received vasopressor(s), percent TBSA injured, admission serum ethanol level, maximum C-reactive protein, and maximum total bilirubin (r² = 0.828).

CONCLUSIONS

There are multiple factors associated with the increased LOS seen in patients with thermal and inhalation injury. This study confirmed and identified novel factors not previously discussed in the literature that were significantly associated with LOS. Expansion of the data submitted to the National Burn Repository and the Burn Quality Improvement Program may be warranted. This study confirms claims from previous studies on inadequacy of current data submitted for benchmarking and under-reimbursement for the care of such a complex population.

Optimization of an empiric vancomycin dosing algorithm for improved target concentration attainment in patients with thermal injury

OBJECTIVE

Vancomycin empirical dosing studies in thermally injured patients have netted low successful target attainment and most excluded renal dysfunction, limiting applicability. In a previous study, the authors performed a retrospective analysis of 124 patients' measured pharmacokinetic parameters to calculate optimal dose and interval for intermittent infusion regimens and find predictors of clearance and total daily dose. The objective of this study was to improve the accuracy of attaining goal therapeutic targets with initial vancomycin regimens in patients with thermal injury through retrospective modeling.

METHODS

In this phase 2 study, variables collected and calculated regimens in phase 1 were utilized to try and create an improved empiric vancomycin dosing algorithm in patients with thermal injury. Logistic regression was utilized to determine best predictors of dosing vancomycin every 6 and 8h. The strongest models were built as individual algorithms and tested for accuracy of target attainment. Each algorithm produced a regimen for each patient that was then tested utilizing each patient's actual measured pharmacokinetic parameters.

RESULTS

Univariable logistic regression of 41 variables identified 27 and 23 to be predictive of dosing every 8 or 6h, respectively. The most predictive multivariable model for dosing every 8h consisted of creatinine clearance (CrCl)≥80ml/min, Acute Kidney Injury Network classification <1, and total body surface area burned≥10 percent. For dosing every 6h, CrCl≥80ml/min, age≤40years old, days since injury≤6, and serum creatinine (SCr)≤0.8 were most predictive. Based on the top 5 multivariable models for each dosing interval, 7 algorithms were built to produce recommended regimens. The highest performing algorithm resulted in trough concentrations of <10mg/L (23%), 10-20mg/L (65%), 15-20mg/L (26%), and >20mg/L (11%); area under the concentration curve (AUC)>400mghr/L (83%); and AUC >400mghr/L without having a trough >20mg/L (72%).

CONCLUSIONS

The algorithm that resulted in the highest target attainment without overdosing recommended 15mg/kg dosed every 24h for CrCl≥30, every 12h for CrCl 31-79, every 8h for patients with CrCl≥80ml/min, and every 6h only if the patient with a CrCl≥80ml/min is also≤40 years old and has a SCr≤0.8. Caution is warranted for groups underrepresented in this study, such as those with very low CrCl, a low BMI, or receiving renal replacement therapy. This algorithm should be validated in other centers for patients with thermal injuries.