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The impact of albumin use during major surgery is unknown, and a dearth of evidence governing its use in major non-cardiac surgery has long precluded its standardization in clinical guidelines.In this study we investigate institutional variation in albumin use among medical centers in the United States during major non-cardiac surgery and explore the association of intraoperative albumin administration with important post-operative outcomes.The study is an observational retrospective cohort analysis performed among 54 hospitals in the Multicenter Perioperative Outcomes Group (MPOG) and includes adult patients who underwent major non-cardiac surgery under general anesthesia between January 2014 and June 2020. The primary endpoint was the incidence of albumin administration. Secondary endpoints acute kidney injury (AKI), net-positive fluid balance, pulmonary complications, and 30-day mortality. Albumin-exposed and -unexposed cases were compared within a propensity score-matched cohort to evaluate associations of albumin use with outcomes.Among 614,215 major surgery cases, albumin was used in 15.3% (mostly isooncotic albumin) but with significant inter-institutional variability in use patterns. Cases involving intraoperative albumin administration were of a higher American Society of Anesthesiologists (ASA) physical status and received larger infused crystalloid volumes, had higher blood loss, and vasopressor use. Overall, albumin was most often administered at high-volume surgery centers with academic affiliation, and within a propensity score-matched cohort (n=153,218), the use of albumin was associated with AKI (aOR 1.24, 95% CI 1.20-1.28, P0.001), severe AKI (aOR 1.45, 95% CI 1.34-1.56, P0.001), net-positive fluid balance (aOR 1.18, 95% CI 1.16-1.20, P0.001), pulmonary complications (aOR 1.56, 95% CI 1.30-1.86, P0.001), and 30-day all-cause mortality (aOR 1.37, 95% CI 1.26-1.49, P0.001).Intravenous albumin is commonly administered among non-cardiac surgeries with significant inter-institutional variability in use in the United States. Albumin was associated with an increased risk of postoperative complications.

We present a narrative review of environmental sustainability aimed at perioperative clinicians. The review will familiarize readers with the triple bottom line framework, which aims to align the goals of delivering high-quality patient care, promoting environmental sustainability, and improving the financial position of health care organizations. We introduce the stabilization wedges model for climate change action adopted for the perioperative setting and discuss areas in which perioperative leaders can make sustainable choices. The goal of this review is to increase awareness among perioperative physicians of the environmental impacts of surgical and anesthetic care, promote engagement with sustainability efforts as a topic of professional concern for our specialty, and inspire new research in perioperative environmental sustainability.

Shortages of opioid analgesics critically disrupt clinical practice and are detrimental to patient safety. There is a dearth of studies assessing the safety implications of drug shortages.We aimed to assess perioperative opioid analgesic use and related postoperative hypoxemia (oxygen saturation less than 90%) in surgical patients exposed to prescription opioid shortages compared to propensity score-matched patients non-exposed to opioid shortages.We conducted a retrospective study including adult patients who underwent elective surgery at The University of California San Francisco in the period August 2018-December 2019. We conducted a Gamma log-link generalized linear model to assess the effect of shortages on perioperative use of opioids and a weighted logistic regression to assess the likelihood of experiencing postoperative hypoxemia.There were 1119 patients exposed to opioid shortages and 2787 matched non-exposed patients. After full matching, patients exposed to shortages used a greater mean of morphine milligram equivalents/day (146.94; 95% confidence interval 123.96-174.16) than non-exposed patients (117.92; 95% confidence interval 100.48-138.38; p = 0.0001). The estimated effect was a 1.25 (95% confidence interval 1.12-1.40; p = 0.0001) times greater use of opioids in patients exposed to opioid shortages than non-exposed patients. After full matching, a greater proportion of patients exposed to shortages (19.06%) experienced hypoxemia compared with non-exposed patients (16.91%). In addition, a greater proportion of patients exposed to opioid shortages (1.20%) experienced hypoxemia reversed by intravenous naloxone administration compared with non-exposed patients (0.44%).Given the shortage prevalence, reliance on opioid medications, and related risk of respiratory depression, harm prevention measures remain critical to prevent postoperative complications that may compromise patients' safety.

Introduction Enhanced recovery after surgery (ERAS) pathways have emerged as a promising strategy to reduce postoperative opioid use and decrease the risk of developing new persistent opioid use in surgical patients. However, the association between ERAS implementation and discharge opioid prescribing practices is unclear. Study design We conducted a retrospective observational quasi-experimental study of opioid-naïve patients aged 18+ undergoing cesarean delivery between February 2015 and December 2019 at a large academic center. An interrupted time series analysis (ITSA) was used to model the changes in pain medication prescribing associated with the implementation of ERAS to account for pre-existing temporal trends. Results Among the 1473 patients (out of 2249 total) who underwent cesarean delivery after ERAS implementation, 80.72% received a discharge opioid prescription vs. 95.36% at baseline. Pre-ERAS daily oral morphine equivalents (OME) on the discharge prescription decreased by 0.48 OME each month (ppppp Conclusion Although ERAS implementation reduced the overall proportion of patients receiving a discharge opioid prescription after cesarean delivery, for the subset of patients receiving an opioid prescription, ERAS implementation may have inadvertently increased the prescribing of daily doses greater than 90 OME. This finding highlights the importance of early and continued evaluation after new policies are implemented.

ImportanceCataract surgery in the US is routinely performed with anesthesia care, whereas anesthesia care for other elective, low-risk, outpatient procedures is applied more selectively.ObjectiveTo identify predictors of anesthesia care in Medicare beneficiaries undergoing cataract surgery and evaluate anesthesia care for cataract surgery compared with other elective, low-risk, outpatient procedures.Design, Setting, and ParticipantsThis population-based, retrospective observational cohort study included Medicare beneficiaries 66 years or older who underwent cataract surgery in 2017. The data were analyzed from August 2020 through May 2021.Interventions (for clinical trials) or Exposures (for observational studies)Anesthesia care during elective, low-risk, outpatient procedures.Main Outcomes and MeasuresPrevalence of anesthesia care during cataract surgery compared with other low-risk procedures; association of anesthesia care with patient, clinician, and health system characteristics; and proportion of patients experiencing a systemic complication within 7 days of cataract surgery compared with patients undergoing other low-risk procedures.ResultsAmong 36 652 cataract surgery patients, the mean (SD) age was 74.7 (6.1) years; 21 690 (59.2%) were female; 2200 (6.6%) were Black and 32 049 (87.4%) were White. Anesthesia care was more common among patients undergoing cataract surgery compared with patients undergoing other low-risk procedures (89.8% vs range of P = .01) nor Charlson Comorbidity Index (CCI) score (CCI of ≥3: adjusted odds ratio, 1.06; 95% CI, 0.95-1.18; P = .28; reference, CCI score of 0-1) was strongly associated with anesthesia care for cataract surgery, but a model comprising a single variable identifying the ophthalmologist predicted anesthesia care with a C statistic of 0.96. Approximately 6.0% of ophthalmologists never used anesthesia care, 76.6% always used anesthesia care, and 17.4% used it for only a subset of patients. Fewer cataract surgery patients experienced systemic complications within 7 days (2833 [7.7%]), even when limited to patients of ophthalmologists who never used anesthesia care (108 [7.4%]), than patients undergoing other low-risk procedures (range, 13.2%-52.2%).Conclusions and RelevanceThe results of this cohort study suggest that systemic complications occurred less frequently after cataract surgery compared with other elective, low-risk, outpatient procedures during which anesthesia care was less commonly used. Anesthesia care was not associated with patient characteristics, such as older age or worse health status, but with the ophthalmologists’ usual approach to cataract surgery sedation. The study findings suggest an opportunity to use anesthesia care more selectively in patients undergoing cataract surgery.

Background Guidelines recommend that clinicians use clinical prediction models to estimate future risk to guide decisions. For example, predicted fracture risk is a major factor in the decision to initiate bisphosphonate medications. However, current methods for developing prediction models often lead to models that are accurate but difficult to use in clinical settings. Objective The objective of this study was to develop and test whether a new metric that explicitly balances model accuracy with clinical usability leads to accurate, easier-to-use prediction models. Methods We propose a new metric called the Time-cost Information Criterion (TCIC) that will penalize potential predictor variables that take a long time to obtain in clinical settings. To demonstrate how the TCIC can be used to develop models that are easier-to-use in clinical settings, we use data from the 2000 wave of the Health and Retirement Study (n=6311) to develop and compare time to mortality prediction models using a traditional metric (Bayesian Information Criterion or BIC) and the TCIC. Results We found that the TCIC models utilized predictors that could be obtained more quickly than BIC models while achieving similar discrimination. For example, the TCIC identified a 7-predictor model with a total time-cost of 44 seconds, while the BIC identified a 7-predictor model with a time-cost of 119 seconds. The Harrell C-statistic of the TCIC and BIC 7-predictor models did not differ (0.7065 vs. 0.7088, P=0.11). Conclusion Accounting for the time-costs of potential predictor variables through the use of the TCIC led to the development of an easier-to-use mortality prediction model with similar discrimination.

Background Neurosurgical spine specialists receive considerable amounts of industry support that may impact the cost of care. The aim of this study was to evaluate the association between industry payments received by spine surgeons and the total hospital and operating room (OR) costs of an anterior cervical discectomy and fusion (ACDF) procedure among Medicare beneficiaries. Methods All ACDF cases were identified among the Medicare carrier files from January 1, 2013, to December 31, 2014, and matched to the Medicare inpatient baseline file. The total hospital and OR charges were obtained for these cases. Charges were converted to cost using year-specific cost-to-charge ratios. Surgeons were identified among the Open Payments database, which is used to quantify industry support. Analyses were performed to examine the association between industry payments received and ACDF costs. Results Matching resulting in the inclusion of 2209 ACDF claims from 2013–2014. In 2013 and 2014, the mean total cost for an ACDF was $21,798 and $21,008, respectively; mean OR cost was $5878 and $6064, respectively. Mann-Whitney U test demonstrated no significant differences in the mean total or OR cost for an ACDF based on quartile of general industry payment received (P = 0.21 and P = 0.54), and linear regression found no association between industry general payments, research support, or investments on the total hospital cost (P = 0.41, P = 0.13, and P = 0.25, respectively), or OR cost for an ACDF (P = 0.35, P = 0.24, and P = 0.40, respectively). Conclusions This study suggests that spine surgeons performing ACDF surgeries may receive industry support without impacting the cost of care.

We present a method for constructing taxonomic trees (e.g., WordNet) using pretrained language models. Our approach is composed of two modules, one that predicts parenthood relations and another that reconciles those predictions into trees. The parenthood prediction module produces likelihood scores for each potential parent-child pair, creating a graph of parent-child relation scores. The tree reconciliation module treats the task as a graph optimization problem and outputs the maximum spanning tree of this graph. We train our model on subtrees sampled from WordNet, and test on non-overlapping WordNet subtrees. We show that incorporating web-retrieved glosses can further improve performance. On the task of constructing subtrees of English WordNet, the model achieves 66.7 ancestor F1, a 20.0% relative increase over the previous best published result on this task. In addition, we convert the original English dataset into nine other languages using Open Multilingual WordNet and extend our results across these languages., NAACL 2021

BACKGROUND Extended-release (ER) opioids are indicated for the management of persistent moderate to severe pain in patients requiring around-the-clock opioid analgesics for an extended period of time. Concerns have been raised regarding safety of ER opioids due to its potential for abuse and dependence. However, little is known about perioperative prescribing practices of ER opioids. This study assessed perioperative prescribing practices of ER opioids in noncancer surgical patients stratified by type of opioid exposure prior to admission and examined predictors of postoperative opioid administration in oral morphine equivalents (OME). METHODS This was a retrospective cohort study using the University of California San Francisco Medical Center electronic health record data. This study included 25,396 adult noncancer patients undergoing elective surgery under general anesthesia in the period 2015-2018. The primary study outcome was predictors of postoperative administration of opioids in hospitalized surgical patients. Secondary outcomes included patients discontinued and initiated on ER opioids during their hospital stay. RESULTS substance use disorder diagnosis and use of opioids, surgery type, and postoperative administration of nonopioid analgesics were associated with postoperative administration of opioids (P < .0001). The estimated adjusted mean (95% confidence interval [CI]) of postoperative administration of OME prior to admission in ER opioid users (170.08 mg; 147.08-196.67) was twice the amount for opioid-naive patients (81.36 mg; 70.7-93.63; P < .0001). One in 5 prior to admission ER opioid users were weaned off ER opioids while hospitalized without adversely affecting their postoperative pain or hospital length of stay (LOS). Four of 5 patients who used ER opioids prior to admission also received ER opioids after surgery, whereas, 1 in 100 opioid-naive patients received ER opioids during their hospital stay. CONCLUSIONS We found significant variability in the perioperative prescribing practices of ER opioids in hospitalized noncancer surgical patients by use of opioids prior to admission and surgery type. Pain medicine practitioners and surgeons may play a significant role tackling the surgery-related risk of exposure to ER opioids and decreasing opioid-related complications.

Background Surgery is a risk factor for opioid initiation and subsequent abuse. Discharge opioid prescription patterns after surgery are often varied and not evidence based, which may lead to unnecessary prescription of opioids. We aimed to assess opioid prescribing and unused opioid prescriptions in ambulatory surgery patients at our academic hospital. Methods We conducted a retrospective observational study based on phone survey and electronic medical records. Adult patients who underwent ambulatory surgery at our large, multisite, tertiary-care hospital system were asked whether they were using the opioids that were prescribed at discharge. Our main outcomes were opioid prescription (defined as being prescribed an opioid on discharge) and unused opioid prescription (defined as being prescribed an opioid but not taking any opioids on postoperative day 1). We evaluated predictors of opioid prescription and unused opioid prescription through univariable and multivariable analyses. We also stratified outcomes by surgical service. Results Of 4248 adult patients who underwent ambulatory surgical procedures, 3279 (77.2%) responded to the survey. Of all responders, 2146 (65.4%) were prescribed postoperative opioids, and 1240 (57.8%) reported not taking them on postoperative day 1. The highest rates of unused opioid prescriptions were for patients whose primary service were orthopedic surgery (65%) and plastic surgery (62%). Discussion Opioid prescribing and unused opioid prescriptions are prevalent in our hospital’s ambulatory surgical population. Patients undergoing selected ambulatory surgical procedures may not require as much opioid as is currently being prescribed.

OBJECTIVE: Delaying cataract surgery is associated with an increased risk of falls, but it is unknown whether routine preoperative testing delays cataract surgery long enough to cause clinical harm. We sought to determine whether the use of routine preoperative testing leads to harm in the form of delayed surgery and falls in Medicare beneficiaries awaiting cataract surgery. DESIGN: Retrospective observational cohort study using 2006-2014 Medicare claims PARTICIPANTS: Medicare beneficiaries age 66+ with a CPT claim for ocular biometry METHODS: We measured the mean and median number of days between ocular biometry and cataract surgery, calculated the proportion of patients waiting >30 days or >90 days for surgery, and determined the odds of having a fall within 90 days of biometry among patients of high-testing physicians (testing performed in ≥75% of their patients) compared to patients of low-testing physicians. We estimated the number of days of delay attributable to high-testing physicians relative to other factors that may determine surgical scheduling. MAIN OUTCOME MEASURES: Incidence of falls occurring between biometry and surgery, odds of falling within 90 days of biometry, and estimated delay in days associated with physician testing behavior . RESULTS: Of 248,345 beneficiaries, 16.4% were patients of high-testing physicians. More patients of high-testing physicians waited >30 days and >90 days to have cataract surgery (31.4% and 8.2% versus 25.0% and 5.5%, respectively, p

Introduction: Opioids are routinely prescribed to manage acute postoperative pain, but changes in postoperative opioid prescribing associated with the marketing of long-acting opioids such as OxyContin have not been described in the surgical cohort. Methods: Using a large commercial claims data set, we studied postoperative opioid prescribing after selected common surgical procedures between 1994 and 2014. For each procedure and year, we calculated the mean postoperative morphine milligram equivalents (MME) filled on the index prescription and assessed the proportion of patients who filled a high-dose prescription (≥350 MME). We reported changes in postoperative opioid prescribing over time and identified predictors of filling a high-dose postoperative opioid prescription. Results: We identified 1,321,264 adult patients undergoing selected common surgical procedures between 1994 and 2014, of whom 80.3% filled a postoperative opioid prescription. One in five surgery patients filled a high-dose postoperative opioid prescription. Between 1994 and 2014, the mean MME filled increased by 145%, 84%, and 85% for lumbar laminectomy/laminotomy, total knee arthroplasty, and total hip arthroplasty, respectively. The procedures most likely to be associated with a high-dose opioid fill were all orthopaedic procedures (AOR 5.20 to 7.55, P < 0.001 for all). Patients whose postoperative opioid prescription included a long-acting formulation had the highest odds of filling a prescription that exceeded 350 MME (AOR 32.01, 95% CI, 30.23–33.90). Discussion: After the US introduction of long-acting opioids such as OxyContin, postoperative opioid prescribing in commercially insured patients increased in parallel with broader US opioid-prescribing trends, most notably among patients undergoing orthopaedic surgical procedures. The increase in the mean annual MME filled starting in the late 1990s was driven in part by the higher proportion of long-acting opioid formulations on the index postoperative opioid prescription filled by orthopaedic surgery patients.

Importance Routine preoperative medical testing is not recommended for patients undergoing low-risk surgery, but testing is common before surgery. A 30-day preoperative testing window is conventionally used for study purposes; however, the extent of routine testing that occurs prior to that point is unknown. Objective To improve on existing cost estimates by identifying all routine preoperative testing that takes place after the decision is made to perform cataract surgery. Design, Setting, and Participants This cross-sectional study assessed preoperative care in a 50% sample of Medicare beneficiaries older than 66 years who underwent ambulatory cataract surgery in 2011. Data analysis was completed from March 2016 to October 2017. Main Outcomes and Measures Using ocular biometry as a procedure-specific indicator to mark the start of the routine preoperative testing window, we measured testing rates in the interval between ocular biometry and cataract surgery and compared this with testing rates in the 6 months preceding biometry. We estimated the total cost of testing that occurred between biometry and cataract surgery. Results A total of 440 857 patients underwent cataract surgery. A total of 423 710 (96.1%) had an ocular biometry claim before index surgery, of whom 264 514 (60.0%) were female; the mean (SD) age of the cohort was 76.1 (6.2) years. A total of 111 998 (25.4%) underwent surgery more than 30 days after biometry. Among patients with a biometry claim, the mean number of tests/patient/month increased from 1.1 in the baseline period to 1.7 in the interval between biometry and cataract surgery. Although preoperative testing peaked in all patients in the 30 days preceding surgery (1.8 tests/patient/month), the subset of patients with no overlap between postbiometry and presurgery periods experienced increased testing rates to 1.8 tests per patient per month in the 30 days after biometry, regardless of the elapsed time between biometry and surgery. The total estimated cost of routine preoperative testing in the full cohort was $22.7 million; we estimate that routine preoperative testing costs Medicare up to $45.4 million annually. Conclusions and Relevance In this study of Medicare beneficiaries, routine preoperative medical testing occurs more often and is costlier than has been reported previously. Extra costs are attributable to testing that occurs prior to the 30-day window preceding surgery. As a cost-cutting measure, routine preoperative medical testing should be avoided in patients with cataracts throughout the interval between ocular biometry and cataract surgery.

Copyright © 2015 Massachusetts Medical Society. BACKGROUND: Routine preoperative testing is not recommended for patients undergoing cataract surgery, because testing neither decreases adverse events nor improves outcomes. We sought to assess adherence to this guideline, estimate expenditures from potentially unnecessary testing, and identify patient and health care system characteristics associated with potentially unnecessary testing. METHODS: Using an observational cohort of Medicare beneficiaries undergoing cataract surgery in 2011, we determined the prevalence and cost of preoperative testing in the month before surgery. We compared the prevalence of preoperative testing and office visits with the mean percentage of beneficiaries who underwent tests and had office visits during the preceding 11 months. Using multivariate hierarchical analyses, we examined the relationship between preoperative testing and characteristics of patients, health system characteristics, surgical setting, care team, and occurrence of a preoperative office visit. RESULTS: Of 440,857 patients, 53% had at least one preoperative test in the month before surgery. Expenditures on testing during that month were $4.8 million higher and expenditures on office visits $12.4 million higher (42% and 78% higher, respectively) than the mean monthly expenditures during the preceding 11 months. Testing varied widely among ophthalmologists; 36% of ophthalmologists ordered preoperative tests for more than 75% of their patients. A patient's probability of undergoing testing was associated mainly with the ophthalmologist who managed the preoperative evaluation. CONCLUSIONS: Preoperative testing before cataract surgery occurred frequently and was more strongly associated with provider practice patterns than with patient characteristics. (Funded by the Foundation for Anesthesia Education and Research and the Grove Foundation.).

The increasing prevalence of obesity may worsen surgical outcomes and confound standardized metrics of surgical quality. Despite anecdotal evidence, the increased risk of complications in obese patients is not accounted for in these metrics. To better understand the impact of obesity on surgical complications, the authors designed a study to measure complication rates in obese patients presenting for a set of elective breast procedures.Using claims data from seven Blue Cross and Blue Shield plans, the authors identified a cohort of obese patients and a nonobese control group who underwent elective breast procedures covered by insurance between 2002 and 2006. The authors compared the proportion of patients in each group who experienced a surgical complication. Using multivariate logistic regression, the authors calculated the odds of developing a surgical complication when obesity was present.There were 2403 patients in the obese group (breast reduction, 80.7 percent; reconstruction, 10.3 percent; mastopexy with augmentation, 1.5 percent; mastopexy alone, 3.5 percent; and augmentation alone, 4.0 percent). The occurrence of complications was compared for each procedure to a nonobese control group of 5597 patients. Overall, 18.3 percent of obese patients had a claim for a complication, compared with only 2.2 percent in the control group (p0.001). Obesity status increased the odds of experiencing a complication by 11.8-fold after adjusting for other variables.Obesity is associated with a nearly 12-fold increased odds of a postoperative complication after elective breast procedures. As quality measures are increasingly applied to surgical evaluation and reimbursement, appropriate risk adjustment to account for the effect of obesity on outcomes will be essential.Risk, II.

Endogenous thrombin potential (ETP) is a measurement of thrombin formation capacity of plasma and may be increased in congenital and acquired hypercoagulable states. We assessed whether ETP was associated with antiphospholipid antibodies (aPL) and with thrombosis history in SLE. ETP was performed in 130 SLE patients using a Siemens ETP Assay on BCS Coagulation System analyzer, that is equipped with software to analyze different components of the coagulation wave form, including lag-time (time to initiate thrombin generation), T-max (estimate of enzymatic rate), c-max (measurement of peak height), and area under the curve (total thrombin formation). Higher T-lag values were found with deep venous thrombosis (DVT) (33.6 ± 15.9 vs. 22.9 ± 14.8, P = 0.0018), myocardial infarction (MI) (43.6 ± 36.4 vs. 24.6 ± 15.1, P = 0.0855) and stroke (27.5 ± 13.5 vs. 24.5 ± 15.8, P = 0.4883) than without. T-max was also higher in patients with DVT (68.4 ± 21.9 vs. 56.5 ± 24.4, P = 0.0300), and MI (123.8 ± 77.0 vs. 57.7 ± 22.1, P > 0.0001) compared to those without. ETP T-lag and T-max were higher for patients with aPL. ETP T-lag and T-max were associated with both venous (DVT) and arterial (stroke, MI) thrombosis in SLE and with aPL. This suggests that ETP measures should now be explored prospectively to determine their predictive value for future thrombosis in SLE.

Objective: To assess mortality risk and extent of increased length of hospital stay in patients with burn injury with preexisting liver disease. Methods: Records of 31,338 adults who were admitted with burns to 70 burn centers were reviewed from the American Burn Association National Burn Repository. Demographics, percentage burn, and medical characteristics of 180 patients with liver disease were compared with all patients without liver disease and to a propensity score–matched sample of 180 patients without liver disease. Risk of mortality as well as lengths of both intensive care and total stay were compared after matching for demographics, burn injury, and preexisting medical conditions. Results: Patients with liver disease were significantly more likely to have a history of a number of medical comorbidities, including alcohol abuse, drug abuse, a psychiatric diagnosis, chronic pulmonary disease, hypertension, and diabetes. Patients with liver disease were significantly more likely to die in the hospital (27.2% vs 6.9%, odds ratio = 5.0, 95% confidence interval = 3.6–7.0, P < .01), and this held even when compared with a propensity score–matched group of patients without liver disease, but with similar demographics, burn injury, and medical profiles. Lengths of both intensive care and total hospital stay were 122.5% (P < .01) and 86.7% (P < .01) longer, respectively, among patients with liver disease than among all other patients. In a matched sample, lengths of both intensive care and total stays were longer, albeit not significantly so (41.6%, P = .12; 35.5%, P = .07). Conclusions: Liver impairment worsens the prognosis in patients with thermal injury.