Choice of Reference Creatinine for Post-Traumatic Acute Kidney Injury Diagnosis

Nomogram based on burn characteristics and the National Early Warning Score to predict survival in severely burned patients

BACKGROUND

Extensive burns are associated with a high mortality rate. Early prediction and action can reduce mortality. The National Early Warning Score (NEWS) is considered the best early warning score for predicting mortality. However, there has been no assessment conducted on the clinical prognostic significance of NEWS in individuals suffering from severe burns. The objective of this research was to establish a nomogram based on burn characteristics and the NEWS to predict survival in severely burned patients.

METHODS

A retrospective analysis was performed on 335 patients diagnosed with extensive burns from 2005 to 2021 in the Department of Burn Surgery of Changhai Hospital, the First Affiliated Hospital of Naval Medical University. Univariate and multivariate analyses were used to determine independent prognostic factors. A nomogram was developed using these prognostic factors and its internal validity was assessed through bootstrap resampling.

RESULTS

The results of multivariate analysis showed that the independent factors affecting the prognosis of severe burn patients were age, full-thickness burn, creatinine, inhalation tracheotomy, and the NEWS, all of which were identified to create the nomogram. The Akaike Information Criterion and Bayesian Information Criterion values of the nomogram demonstrated superior goodness-of-fit in predicting severe burns compared to NEWS, with lower scores (195.21 vs. 201.24; 221.91 vs. 224.12, respectively). The bootstrap-adjusted concordance index (C-index) of the nomogram yielded a higher value of 0.923(95 % CI 0.892-0.953), compared to NEWS which had a C-index of 0.699 (95 % CI 0.628-0.770). The calibration curves demonstrated excellent agreement between predicted probabilities and observed outcomes in the nomogram analysis. Furthermore, decision curve analysis indicated promising clinical utility for the proposed nomogram model. By applying an appropriate cutoff value derived from receiver operating characteristics curve analysis, it was observed that the high-risk group identified by the nomogram exhibited a significantly higher mortality rate than the low-risk group.

CONCLUSION

This study introduces an innovative nomogram that predicts the survival rate of individuals with severe burn injuries by combining clinical attributes and laboratory examinations, demonstrating superior efficacy compared to conventional NEWS systems.

Exposure to statin therapy decreases the incidence of venous thromboembolism after trauma

INTRODUCTION

Venous thromboembolism (VTE) is a leading cause of morbidity and mortality in trauma patients, despite chemoprophylaxis. Statins have been shown capable of acting upon the endothelium. We hypothesized that statin therapy in the pre- or in-hospital settings leads to a decreased incidence of VTE.

METHODS

We conducted a retrospective cohort study of injured patients who received statin therapy pre- or in-hospital. Adult, highest-level trauma activation patients admitted from January 2018 to June 2022 were included. Patients on prehospital anticoagulants, had history of inherited bleeding disorder, and who died within the first 24 hours were excluded. Statin users were matched to nonusers by statin use indications including age, current heart and cardiovascular conditions and history, hyperlipidemia, injury severity, and body mass index. Time to in-hospital statin initiation and occurrence of VTE and other complications within 60 days were collected. Differences between groups were determined by univariate, multivariable logistic regression, and Cox proportional hazard analyses.

RESULTS

Of 3,062 eligible patients, 79 were statin users, who were matched to 79 nonusers. There were no differences in admission demographics, vital signs, injury pattern, transfusion volumes, lengths of stay, or mortality between groups. The overall VTE incidence was 10.8% (17 of 158). Incidence of VTE in statin users was significantly lower (3%) than nonusers (19%; p = 0.003). Differences between statin users and nonusers were observed for rates of deep vein thrombosis (0% vs. 9%), pulmonary embolism (3% vs. 15%), and sepsis (0% vs. 5%). Exposure to statins was associated with an 82% decreased risk of developing VTE (hazard ratio, 0.18; 95% confidence interval, 0.04-0.86; p = 0.033).

CONCLUSION

Statin exposure was associated with decline in VTE and lower individual rates of deep vein thrombosis, pulmonary embolism, and sepsis. Our findings indicate that statins should be evaluated further as a possible adjunctive therapy for VTE chemoprophylaxis after traumatic injury.

LEVEL OF EVIDENCE

Therapeutic/Care Management; Level IV.

Predictors of oliguria in post-traumatic acute kidney injury

BACKGROUND

Acute kidney injury is classified by urine output into non-oliguric and oliguric variants. Non-oliguric acute kidney injury has lower morbidity and mortality and accounts for up to 64% of acute kidney injury in hospitalized patients. However, the incidence of non-oliguric acute kidney injury in the trauma population and whether the 2 variants of acute kidney injury share the same risk factors is unknown. We hypothesized that oliguria would be present in the majority of acute kidney injury in severely injured trauma patients and that unique risk factors would predispose patients to the development of oliguria.

METHODS

Patients admitted to the trauma intensive care unit and diagnosed with an acute kidney injury between 2016 to 2021 were identified. Cases were categorized based on urine output into oliguric (<400 mL per day) and non-oliguric (>400 mL per day) disease. Risk factors, management, and outcomes were compared. Logistic regression was used to identify risk factors associated with oliguria.

RESULTS

A total of 227 patients met inclusion criteria. Non-oliguric acute kidney injury accounted for 74% of all cases and was associated with greater survival (78% vs 35.6%, P < .001). Using logistic regression, female sex, vasopressor use, and a greater net fluid balance at 48 hours were all predictive of oliguria (while controlling for age, race, shock index, massive transfusion, operative intervention, cardiac arrest, and nephrotoxic medication exposure).

CONCLUSION

Non-oliguria accounts for the majority of post-traumatic acute kidney injury and is associated with improved survival. Specific risk factors for the development of oliguric acute kidney injury include female sex, vasopressor use, and a higher net fluid balance at 48 hours.

Early Fibrinogen Replacement to Treat the Endotheliopathy of Trauma: Novel Resuscitation Strategies in Severe Trauma

The authors provide a comprehensive review of the endothelial glycocalyx, the components that may be targeted to improve clinical outcomes, and the next steps for evaluation in human subjects.

Association of creatinine-albumin ratio with 28-day mortality in major burned patients: A retrospective cohort study

BACKGROUND

Serum creatinine (Cr) and Albumin (Alb) have emerged as prognostic factors for mortality in many diseases including burned patients. However, few studies report the relationship between Cr/Alb ratio and major burned patients. The purpose of this study is to make evaluation of efficacy of Cr/Alb ratio in predicting 28-day mortality in major burned patients.

METHOD

Based on a local largest tertiary hospital in South of China, we retrospectively analyzed data of 174 patients with total burn area surface (TBSA) ≥ 30% from January 2010 to December 2022. Receiver operating characteristic curve (ROC), logistic analysis, and Kaplan-Meier analysis were performed to evaluate the association between Cr/Alb ratio and 28-day mortality. Integrated discrimination improvement (IDI), and net reclassification improvement (NRI) were used to estimate the improvements in new model performance.

RESULTS

28-day mortality rate was 13.2% (23/174) in burned patients. Cr/Alb on admission at level of 3.340μmol/g showed the best discrimination between survivors and non-survivors after admission at 28 days. The result of multivariate logistic analysis suggested that age (OR, 1.058 [95%CI 1.016-1.102]; p = 0.006), higher FTSA (OR, 1.036 [95%CI 1.010-1.062]; p = 0.006), and higher level of Cr/Alb ratio (OR, 6.923 [95CI% 1.743-27.498]; p = 0.006) were independently associated with 28 day-mortality. A regression model was constructed by logit(p) = 0.057 *Age + 0.035 *FTBA + 1.935 * Cr/Alb - 6.822. The model showed a better discrimination and risk reclassification compared with ABSI and rBaux score.

CONCLUSIONS

High Cr/Alb ratio at admission is a herald of poor outcome. The model generated from multivariate analysis could serve as an alternative prediction tool among major burned patients.

Concordance between glomerular filtration rate estimation equations and 4-hour urinary creatinine clearance in critically ill patients with severe trauma

BACKGROUND AND OBJECTIVE

There is a growing body of evidence that the equations used to estimate the glomerular filtration rate (GFR) are not suitable in critically ill patients, a population whose GFR fluctuates continuously. Glomerular filtration is usually estimated by measuring urine creatinine clearance (CrCl) at various time points. The aim of our study was to evaluate the performance of the most widely used GFR calculators in the subpopulation of critically ill patients admitted for severe trauma, and to compare the results against determinations of CrCl in urine collected over a 4-h period (4h-CrCl).

MATERIAL AND METHODS

Observational study in patients hospitalized for severe trauma. We measured the 4h-CrCl and estimated GFR using the Cockcroft-Gault, modified Jelliffe, MDRD, t-MDRD, and CKD-EPI equations, adjusting the results for body surface area (BSA) (ml/min/1.73m2). Data were analysed using R version 4.0.4.

RESULTS

A total of 85 patients were included. Median age was 51 years, and 68 were men (78.82%). The mean BSA-adjusted 4h-CrCl (4h-ClCr/1.73m2) was 84.5 ml/min/1.73m2. We found that GFR estimated using the t-MDRD equation correlated significantly with 4h-CrCl/1.73m2. The Cockcroft-Gault equation correlated significantly with 4h-CrCl/1.73m2 when GFR was greater than 130ml/min/m2.

CONCLUSIONS

In ICU patients, glomerular filtration can be reliably estimated by determining urine CrCl, but GFR calculators are not accurate in this population.

Selection of appropriate reference creatinine estimate for acute kidney injury diagnosis in patients with severe trauma

BACKGROUND

In patients with severe trauma, the diagnosis of acute kidney injury (AKI) is important because it is a predictive factor for poor prognosis and can affect patient care. The diagnosis and staging of AKI are based on change in serum creatinine (SCr) levels from baseline. However, baseline creatinine levels in patients with traumatic injuries are often unknown, making the diagnosis of AKI in trauma patients difficult. This study aimed to enhance the accuracy of AKI diagnosis in trauma patients by presenting an appropriate reference creatinine estimate (RCE).

METHODS

We reviewed adult patients with severe trauma requiring intensive care unit admission between 2015 and 2019 (n=3,228) at a single regional trauma center in South Korea. AKI was diagnosed based on the current guideline published by the Kidney Disease: Improving Global Outcomes organization. AKI was determined using the following RCEs: estimated SCr75-modification of diet in renal disease (MDRD), trauma MDRD (TMDRD), admission creatinine level, and first-day creatinine nadir. We assessed inclusivity, prognostic ability, and incrementality using the different RCEs.

RESULTS

The incidence of AKI varied from 15% to 46% according to the RCE used. The receiver operating characteristic curve of TMDRD used to predict mortality and the need for renal replacement therapy (RRT) had the highest value and was statistically significant (0.797, P<0.001; 0.890, P=0.002, respectively). In addition, the use of TMDRD resulted in a mortality prognostic ability and the need for RRT was incremental with AKI stage.

CONCLUSIONS

In this study, TMDRD was feasible as a RCE, resulting in optimal post-traumatic AKI diagnosis and prognosis.

A case-control study of risk factors for survival after laparotomy in patients with pancreatic trauma

BACKGROUND

Pancreatic trauma results in significant morbidity and mortality. However, few studies have investigated the postoperative prognostic factors in patients with pancreatic trauma.

MATERIAL AND METHODS

A retrospective study was conducted on consecutive patients with pancreatic trauma who underwent surgery in a national referral trauma center. Clinical data were retrieved from the electronic medical system. Univariate and binary logistic regression analyses were performed to identify the perioperative clinical parameters that may predict the factors of mortality of the patients.

RESULTS

A total of 150 patients underwent laparotomy due to pancreatic trauma during the study period. 128(85.4%) patients survived and 22 (14.6%) patients died due to pancreatic injury (10 patients died of recurrent intra-abdominal active hemorrhage and 12 died of multiple organ failure). Univariate analysis showed that age, hemodynamic status, and injury severe score (ISS) as well as postoperative serum levels of C-reactive protein (CRP), procalcitonin, albumin, creatinine and the volume of intraoperative blood transfusion remained strongly predictive of mortality (P < 0.05). Binary logistic regression analysis showed that the independent risk factors for prognosis after pancreatic trauma were age (P = 0.010), preoperative hemodynamic instability (P = 0.015), postoperative CRP ≥154 mg/L (P = 0.014), and postoperative serum creatinine ≥177 μmol/L (P = 0.027).

CONCLUSIONS

In this single-center retrospective study, we demonstrated that preoperative hemodynamic instability, severe postoperative inflammation (CRP ≥154 mg/L) and acute renal failure (creatinine ≥177 μmol/L) were associated with a significant risk of mortality after pancreatic trauma.

Correlation and Diagnostic Value of Serum Cys-C, RBP4, and NGAL with the Condition of Patients with Traumatic Acute Kidney Injury

There is a lack of targeted biomarkers that can diagnose Acute Kidney Injury (AKI) early and accurately, which leads to deterioration of renal function and even death in patients who do not receive timely and effective treatment. In recent years, an increasing number of studies have shown that AKI-related markers such as cystatin C (Cys-C) and retinol-binding protein (RBP) can be used for early diagnosis of AKI to a certain extent. A total of 262 subjects were included in this study, of which 132 patients with traumatic AKI were enrolled in one group and named as the AKI group; 130 healthy subjects were enrolled in another group and named as the healthy group. AKI patients with different conditions were classified into AKI phase I, II, and III according to the KDIGO AKI diagnostic criteria, with 45, 59, and 28 in each group. In this study, we examined and compared serum Cys-C, RBP4, and neutrophil gelatinase-associated lipid transport protein (NGAL) levels between the AKI and healthy groups and between patients with AKI of different conditions, and the correlation and diagnostic value of three serum markers with the condition of traumatic AKI patients were also analyzed. The results showed that serum Cys-C, RBP4, and NGAL were significantly higher in the AKI group compared with the healthy group (P < 0.05), and the mean concentrations of the three serum markers increased as the severity of the disease increased, while correlation analysis showed that all three serum markers were positively correlated with serum Scr levels (P < 0.001). Further ROC curve analysis was performed, and the diagnostic values of serum Cys C, RBP4, and NGAL alone and in combination for traumatic AKI were 0.769, 0.741, 0.771, and 0.905, respectively. In short, serum Cys C, RBP4, NGAL have important value for the assessment and diagnosis of traumatic AKI patients.

Importance of duration of acute kidney injury after severe trauma: a cohort study

Background

Acute kidney injury (AKI) is common after severe trauma. AKI incidence and AKI stage have previously been shown to be associated with poor outcomes after trauma. However, AKI duration may also be important for outcomes after trauma, given that it is associated with long-term morbidity and mortality in general intensive care unit (ICU) and hospitalized patients. We hypothesized that duration of AKI is independently associated with poor outcomes after trauma.

Methods

A cohort study was conducted at a single, level 1 trauma center. Patients admitted to the ICU between 2009 and 2018 were included. Data were extracted from the trauma registry and electronic medical records. AKI within 7 days from presentation was defined according to the Kidney Disease Improving Global Outcomes guidelines. Multivariable analyses were performed to assess the association between AKI incidence, AKI stage, and AKI duration with outcomes including prolonged ICU and hospital length of stay, discharge to home, and mortality.

Results

Of 7049 patients included, 72% were male, the median age was 41 years (IQR 27–58), and 10% died. The AKI incidence was 45%, with 69% of these patients presenting with AKI on arrival. The majority (73%) of patients who suffered AKI recovered within 2 days. After adjustment in separate models, AKI incidence, AKI stage and AKI duration were each associated with prolonged hospitalization, an unfavorable discharge disposition, and mortality. AKI stage and duration were not used in the same model due to collinearity.

Conclusions

Post-traumatic AKI was common on arrival and frequently short lasting. Duration correlated with highest AKI stage, and both were separately associated with prolonged hospitalization, discharge destination other than home, and mortality on adjusted analyses. Given the high incidence of AKI on arrival, stage or duration may be better targets for future interventions and quality improvement initiatives to improve outcomes after post-traumatic AKI.

Level of evidence

III. Prognostic.

Do early non-steroidal anti-inflammatory drugs for analgesia worsen acute kidney injury in critically ill trauma patients? An inverse probability of treatment weighted analysis

BACKGROUND

Administration of nonsteroidal anti-inflammatory drugs (NSAIDs) for acute posttraumatic analgesia is increasing in popularity as an alternative to opioids despite reservations regarding its potential impact on the development of acute kidney injury (AKI). We hypothesized that early NSAID administration for analgesia would be associated with worsened renal function in severely injured trauma patients.

METHODS

A retrospective cohort study of severely injured adult (≥16 years) patients admitted to the intensive care unit with ≥1 rib fracture between 2010 and 2017 was performed. The early NSAID group was defined by receipt of one or more doses of NSAID within the first 48 hours of hospitalization. Acute kidney injury diagnosis and staging were defined by the Kidney Disease Improving Global Outcomes Guidelines. The primary outcome was a composite measure of two outcomes within the first week of hospitalization: (1) AKI progression (increase in AKI stage from arrival) or (2) death. Secondary outcomes included AKI progression, AKI improvement, AKI duration, and mortality. Inverse propensity of treatment weights were generated using clinically sound covariates suspected to be associated with the decision to give early NSAIDs and the primary or secondary outcomes. Multivariable analyses were performed adjusting for inverse propensity of treatment weights, covariates, and length of stay.

RESULTS

Of 2,340 patients, 268 (11%) were administered early NSAIDs. When compared with the control group, patients who received early NSAIDs were less severely injured. Renal outcomes were worse in the control group. Standardized mean differences were minimal after weighting. On multivariable analysis, administration of early NSAIDs was not associated with worsened renal outcomes or increased mortality.

CONCLUSION

Although only 11% of patients received early NSAIDs after trauma for analgesia, early NSAID exposure was not associated with increased AKI progression, decreased AKI improvement, prolonged duration, or increased mortality. Given the lack of evidence showing harm, early NSAIDs for analgesia may be underused for severely injured patients.

LEVEL OF EVIDENCE

Prognostic, level III, Therapeutic, level IV.

Urinary cell cycle arrest proteins urinary tissue inhibitor of metalloprotease 2 and insulin-like growth factor binding protein 7 predict acute kidney injury after severe trauma: A prospective observational study

BACKGROUND

Recognition and clinical diagnosis of acute kidney injury (AKI) after trauma is difficult. The majority of trauma patients do not have a known true baseline creatinine, which makes application of the guidelines set forth by the international guidelines difficult to apply. Use of alternative biomarkers of renal dysfunction in trauma patients may be beneficial. We hypothesized that urinary tissue inhibitor of metalloprotease 2 (TIMP-2) × insulin-like growth factor binding protein 7 (IGFBP-7) would accurately predict AKI development in severely injured trauma patients.

METHODS

A prospective observational study of adult (≥16 years old) trauma intensive care unit (ICU) patients was performed between September 2018 to March 2019. Urine was collected on ICU admission and was measured for TIMP-2 × IGFBP-7. Univariate, multivariable, and receiver operating characteristic curve analyses were performed using the optimal threshold generated by a Youden index.

MAIN RESULTS

Of 88 included patients, 75% were male, with a median injury severity score was 27 (interquartile range [IQR], 17-34), and age of 40 years (IQR, 28-54 years). Early AKI developed in 39 patients (44%), and of those, 7 (8%) required dialysis within 48 hours. Patients without early AKI had a TIMP-2 × IGFBP-7 of 0.17 U (IQR, 0.1-0.3 U), while patients with early AKI had a TIMP-2 × IGFBP-7 of 0.46 U (IQR, 0.17-1.29 U; p < 0.001). On multivariable analyses, TIMP-2 × IGFBP-7 was associated with AKI development (p = 0.02) and need for dialysis (p = 0.03). Using the optimal threshold 0.33 U to predict AKI, the area under the receiver operating characteristic curve was 0.731, with an accuracy of 0.75, sensitivity of 0.72, and specificity of 0.78.

CONCLUSION

Urinary TIMP-2 × IGFBP-7 measured on ICU admission accurately predicted 48-hour AKI and was independently associated with AKI and dialysis requirement after trauma and is a promising screening tool for treatment.

LEVEL OF EVIDENCE

Prognostic, prospective, observational study, level III.