Venous glucose and arterial lactate as biochemical predictors of mortality in clinically severely injured trauma patients--a comparison with ISS and TRISS

Real-Time Measurements of Oral Mucosal Carbon Dioxide (POMCO2) Reveals an Inverse Correlation With Blood Pressure in a Porcine Model of Coagulopathic Junctional Hemorrhage

INTRODUCTION

Shock states that occur during, for example, profound hemorrhage can cause global tissue hypoperfusion leading to organ failure. There is an unmet need for a reliable marker of tissue perfusion during hemorrhage that can be followed longitudinally. Herein, we investigated whether longitudinal POMCO2 tracks changes in hemodynamics in a swine model of coagulopathic uncontrolled junctional hemorrhage.

MATERIALS AND METHODS

Female Yorkshire-crossbreed swine (n = 7, 68.1 ± 0.7 kg) were anesthetized and instrumented for continuous measurement of mean arterial pressure (MAP). Coagulopathy was induced by the exchange of 50 to 60% of blood volume with 6% Hetastarch over 30 minutes to target a hematocrit of <15%. A 4.5-mm arteriotomy was made in the right common femoral artery with 30 seconds of free bleeding. POMCO2 was continuously measured from baseline through hemodilution, hemorrhage, and a subsequent 3-h intensive care unit period. Rotational thromboelastometry and blood gases were measured.

RESULTS

POMCO2 and MAP showed no significant changes during the hemodilution phase of the experiment, which produced coagulopathy evidenced by prolonged clot formation times. However, POMCO2 increased because of the uncontrolled hemorrhage by 11.3 ± 3.1 mmHg and was inversely correlated with the drop (17.9 ± 5.9 mmHg) in MAP (Y = -0.4122*X + 2.649, P = .02, r2 = 0.686). In contrast, lactate did not significantly correlate with the changes in MAP (P = .35) or POMCO2 (P = .37).

CONCLUSIONS

Despite the logical appeal of measuring noninvasive tissue CO2 measurement as a surrogate for gastrointestinal perfusion, prior studies have only reported snapshots of this readout. The present investigation shows real-time longitudinal measurement of POMCO2 to confirm that MAP inversely correlates to POMCO2 in the face of coagulopathy. The simplicity of measuring POMCO2 in real time can provide an additional practical option for military or civilian medics to monitor trends in hypoperfusion during hemorrhagic shock.

Serum Lactate Level as a Predictor for Blood Transfusion in Postpartum Hemorrhage

OBJECTIVE

Postpartum hemorrhage (PPH) is the leading cause of maternal morbidity and mortality. At present, there are no reliable clinical or laboratory indicators to identify which patients might require blood transfusions during a PPH. Serum lactate has long been used as an early biomarker of tissue hypoperfusion in trauma settings. The aim of this study is to understand serum lactate's role in the management of obstetric hemorrhage.

STUDY DESIGN

A retrospective chart review was performed of women who delivered between 2016 and 2019 at our institution and experienced a PPH. The patients were divided into two groups: those with a normal serum lactate level, defined as ≤2 mmol/L, and those with an abnormal serum lactate level, defined as >2 mmol/L. Need for packed red blood cell transfusion, as part of the resuscitation, was assessed for both groups.

RESULTS

During the study period, 938 women experienced PPH. Of these, 108 (11.5%) had a normal serum lactate, ≤2 mmol/L, and 830 (88.5%) had an abnormal lactate, >2 mmol/L. Women with elevated lactate levels were more likely to receive a blood transfusion versus those with a normal lactate level (57.0 vs. 46.3%, p = 0.035, respectively). Additionally, the average number of blood transfusions administered was significantly higher in the abnormal lactate group versus in the normal lactate group (1.34 vs. 0.97, respectively, p = 0.004). In a multivariable linear regression model, increasing serum lactate levels were found to be predictive of requiring more than 1 unit of blood (p < 0.001).

CONCLUSION

Women with elevated serum lactate levels were more likely to require blood transfusions during a PPH versus those with a normal serum lactate level. Thus, serum lactate levels are useful as an early indicator of requirement for blood transfusion in the management of obstetric hemorrhage.

KEY POINTS

· Lactate is a biomarker for blood transfusion in trauma.. · Lactate's role in PPH is unknown.. · Elevated lactate predicts receiving more blood transfusions..

Acute Kidney Injury: Iterative Development of an Audit Tool for Trauma Patients

BACKGROUND

Acute kidney injury is a low-volume, high-risk complication in trauma patients and is associated with prolonged hospital length of stay and increased mortality. Yet, no audit tools exist to evaluate acute kidney injury in trauma patients.

OBJECTIVE

This study aimed to describe the iterative development of an audit tool to evaluate acute kidney injury following trauma.

METHODS

Our performance improvement nurses developed an audit tool to evaluate acute kidney injury in trauma patients using an iterative, multiphase process conducted from 2017 to 2021, which included a review of our Trauma Quality Improvement Program data, trauma registry data, literature review, multidisciplinary consensus approach, retrospective and concurrent review, and continuous audit and feedback for piloted and finalized versions of the tool.

RESULTS

The final acute kidney injury audit tool can be completed within 30 min using data obtained from the electronic medical record and consists of six sections, including identification criteria, source potential causes, source treatment, acute kidney injury treatment, dialysis indications, and outcome status.

CONCLUSION

The iterative development and testing of an acute kidney injury audit tool improved the uniform data collection, documentation, audit, and feedback of best practices to positively impact patient outcomes.

Indicative factors for surgical or angiographic intervention in hemodynamically stable patients with blunt abdominal trauma: A retrospective cohort study

INTRODUCTION

The standard of care for intraperitoneal injury in hemodynamically stable patients after blunt abdominal trauma has been replaced by non-operative management (NOM). However, selective NOM, depending on the situation, seems necessary in determining the treatment plan. In this study, we attempted to identify risk factors for surgical or angiographic intervention (SAI) in hemodynamically stable blunt abdominal trauma patients.

METHODS

This retrospective study which included adult patients who were brought to a regional trauma center was conducted from March 2015 to October 2019. We evaluated the characteristics of blunt abdominal trauma patients and analyzed factors that were related to the requirement of SAI in these patients. Patients were divided into SAI and conservative management (CM) groups.

RESULTS

We reviewed 1,176 patients, and after exclusions, of whom 248 blunt abdominal trauma and free fluid observed on CT were identified. The mean pulse rate was higher in the SAI than in the CM (P=0.025). Laboratory findings showed that lactate and delta neutrophil index (DNI) levels were higher in the SAI than in the CM (P=0.002 and 0.026 respectively). Additionally, the mean free fluid size in the SAI (85.69mm) was significantly larger than that in the CM (68.12mm; P=0.001), and blush was more frequently observed in the SAI (P<0.001). In multivariate analysis, only blush was an independent prognostic factor for SAI (OR 11.7, 95% CI, 5.1-30.8, P<0.001).

CONCLUSION

In hemodynamically stable patients with blunt abdominal trauma, blush but also high lactate and DNI are associated with the requirement of interventional radiology and/or surgery.

A Novel Strategy for Predicting 72-h Mortality After Admission in Patients With Polytrauma: A Study on the Development and Validation of a Web-Based Calculator

Background

Early and accessible screening of patients with polytrauma at a high risk of hospital death is essential. The purpose of this research was to seek an accurate and convenient solution to predict deaths occurring within 72 h after admission of these patients.

Methods

A secondary analysis was conducted on 3,075 patients with polytrauma from the Dryad database. We imputed missing values in eligible individuals with the k-nearest neighbor algorithm and then randomly stratified them into the training group (n = 2,461) and the validation group (n = 614) based on a proportion of 8:2. The restricted cubic spline, univariate, backward stepwise, and multivariate logistic regression methods were employed to determine the suitable predictors. Calibration and receiver operating characteristic (ROC) curves were applied to assess the calibration and discrimination of the obtained model. The decision curve analysis was then chosen as the measure to examine the clinical usage.

Results

Age, the Glasgow Coma Scale score, the Injury Severity Score, base excess, and the initial lactate level were inferred as independent prognostic factors related to mortality. These factors were then integrated and applied to construct a model. The performance of calibration plots, ROC curves, and decision curve analysis indicated that the model had satisfactory predictive power for 72-h mortality after admission of patients with polytrauma. Moreover, we developed a nomogram for visualization and a web-based calculator for convenient application (https://songandwen.shinyapps.io/DynNomapp/).

Conclusions

A convenient web-based calculator was constructed to robustly estimate the risk of death in patients with polytrauma within 72 h after admission, which may aid in further rationalization of clinical decision-making and accurate individual treatment.

Serum Lactate Level in Early Stage Is Associated With Acute Kidney Injury in Traumatic Brain Injury Patients

Background

Acute kidney injury (AKI) is a common complication in the clinical practice of managing patients with traumatic brain injury (TBI). Avoiding the development of AKI is beneficial for the prognosis of patients with TBI. We designed this study to testify whether serum lactate could be used as a predictive marker of AKI in patients with TBI.

Materials and Methods

In total, 243 patients with TBI admitted to our hospital were included in this study. Univariate and multivariate logistic regression analyses were utilized to analyze the association between lactate and AKI. The receiver operating characteristic (ROC) curves were drawn to verify the predictive value of lactate and the logistic model.

Results

Acute kidney injury group had higher age (p = 0.016), serum creatinine (p < 0.001), lactate (p < 0.001), and lower Glasgow Coma Scale (GCS; p = 0.021) than non-AKI group. Multivariate logistic regression showed that age [odds ratio (OR) = 1.026, p = 0.022], serum creatinine (OR = 1.020, p = 0.010), lactate (OR = 1.227, p = 0.031), fresh frozen plasma (FFP) transfusion (OR = 2.421, p = 0.045), and platelet transfusion (OR = 5.502, p = 0.044) were risk factors of AKI in patients with TBI. The area under the ROC curve (AUC) values of single lactate and predictive model were 0.740 and 0.807, respectively.

Conclusion

Serum lactate level in the early phase is associated with AKI in patients with TBI. Lactate is valuable for clinicians to evaluate the probability of AKI in patients with TBI.

Monitoring the tissue perfusion during hemorrhagic shock and resuscitation: tissue-to-arterial carbon dioxide partial pressure gradient in a pig model

Background

Despite much evidence supporting the monitoring of the divergence of transcutaneous partial pressure of carbon dioxide (tcPCO₂) from arterial partial pressure carbon dioxide (artPCO₂) as an indicator of the shock status, data are limited on the relationships of the gradient between tcPCO₂ and artPCO₂ (tc-artPCO₂) with the systemic oxygen metabolism and hemodynamic parameters. Our study aimed to test the hypothesis that tc-artPCO₂ can detect inadequate tissue perfusion during hemorrhagic shock and resuscitation.

Methods

This prospective animal study was performed using female pigs at a university-based experimental laboratory. Progressive massive hemorrhagic shock was induced in mechanically ventilated pigs by stepwise blood withdrawal. All animals were then resuscitated by transfusing the stored blood in stages. A transcutaneous monitor was attached to their ears to measure tcPCO₂. A pulmonary artery catheter (PAC) and pulse index continuous cardiac output (PiCCO) were used to monitor cardiac output (CO) and several hemodynamic parameters. The relationships of tc-artPCO₂ with the study parameters and systemic oxygen delivery (DO₂) were analyzed.

Results

Hemorrhage and blood transfusion precisely impacted hemodynamic and laboratory data as expected. The tc-artPCO₂ level markedly increased as CO decreased. There were significant correlations of tc-artPCO₂ with DO₂ and COs (DO₂: r = − 0.83, CO by PAC: r = − 0.79; CO by PiCCO: r = − 0.74; all P < 0.0001). The critical level of oxygen delivery (DO_2crit) was 11.72 mL/kg/min according to transcutaneous partial pressure of oxygen (threshold of 30 mmHg). Receiver operating characteristic curve analyses revealed that the value of tc-artPCO₂ for discrimination of DO_2crit was highest with an area under the curve (AUC) of 0.94, followed by shock index (AUC = 0.78; P < 0.04 vs tc-artPCO₂), and lactate (AUC = 0.65; P < 0.001 vs tc-artPCO₂).

Conclusions

Our observations suggest the less-invasive tc-artPCO₂ monitoring can sensitively detect inadequate systemic oxygen supply during hemorrhagic shock. Further evaluations are required in different forms of shock in other large animal models and in humans to assess its usefulness, safety, and ability to predict outcomes in critical illnesses.

Machine Learning Consensus Clustering Approach for Patients with Lactic Acidosis in Intensive Care Units

BACKGROUND

Lactic acidosis is a heterogeneous condition with multiple underlying causes and associated outcomes. The use of multi-dimensional patient data to subtype lactic acidosis can personalize patient care. Machine learning consensus clustering may identify lactic acidosis subgroups with unique clinical profiles and outcomes.

METHODS

We used the Medical Information Mart for Intensive Care III database to abstract electronic medical record data from patients admitted to intensive care units (ICU) in a tertiary care hospital in the United States. We included patients who developed lactic acidosis (defined as serum lactate ≥ 4 mmol/L) within 48 h of ICU admission. We performed consensus clustering analysis based on patient characteristics, comorbidities, vital signs, organ supports, and laboratory data to identify clinically distinct lactic acidosis subgroups. We calculated standardized mean differences to show key subgroup features. We compared outcomes among subgroups.

RESULTS

We identified 1919 patients with lactic acidosis. The algorithm revealed three best unique lactic acidosis subgroups based on patient variables. Cluster 1 (n = 554) was characterized by old age, elective admission to cardiac surgery ICU, vasopressor use, mechanical ventilation use, and higher pH and serum bicarbonate. Cluster 2 (n = 815) was characterized by young age, admission to trauma/surgical ICU with higher blood pressure, lower comorbidity burden, lower severity index, and less vasopressor use. Cluster 3 (n = 550) was characterized by admission to medical ICU, history of liver disease and coagulopathy, acute kidney injury, lower blood pressure, higher comorbidity burden, higher severity index, higher serum lactate, and lower pH and serum bicarbonate. Cluster 3 had the worst outcomes, while cluster 1 had the most favorable outcomes in terms of persistent lactic acidosis and mortality.

CONCLUSIONS

Consensus clustering analysis synthesized the pattern of clinical and laboratory data to reveal clinically distinct lactic acidosis subgroups with different outcomes.

Machine Learning Prediction Models for Mortality in Intensive Care Unit Patients with Lactic Acidosis

Background: Lactic acidosis is the most common cause of anion gap metabolic acidosis in the intensive care unit (ICU), associated with poor outcomes including mortality. We sought to compare machine learning (ML) approaches versus logistic regression analysis for prediction of mortality in lactic acidosis patients admitted to the ICU. Methods: We used the Medical Information Mart for Intensive Care (MIMIC-III) database to identify ICU adult patients with lactic acidosis (serum lactate ≥4 mmol/L). The outcome of interest was hospital mortality. We developed prediction models using four ML approaches consisting of random forest (RF), decision tree (DT), extreme gradient boosting (XGBoost), artificial neural network (ANN), and statistical modeling with forward stepwise logistic regression using the testing dataset. We then assessed model performance using area under the receiver operating characteristic curve (AUROC), accuracy, precision, error rate, Matthews correlation coefficient (MCC), F1 score, and assessed model calibration using the Brier score, in the independent testing dataset. Results: Of 1919 lactic acidosis ICU patients, 1535 and 384 were included in the training and testing dataset, respectively. Hospital mortality was 30%. RF had the highest AUROC at 0.83, followed by logistic regression 0.81, XGBoost 0.81, ANN 0.79, and DT 0.71. In addition, RF also had the highest accuracy (0.79), MCC (0.45), F1 score (0.56), and lowest error rate (21.4%). The RF model was the most well-calibrated. The Brier score for RF, DT, XGBoost, ANN, and multivariable logistic regression was 0.15, 0.19, 0.18, 0.19, and 0.16, respectively. The RF model outperformed multivariable logistic regression model, SOFA score (AUROC 0.74), SAP II score (AUROC 0.77), and Charlson score (AUROC 0.69). Conclusion: The ML prediction model using RF algorithm provided the highest predictive performance for hospital mortality among ICU patient with lactic acidosis.

Comparison of base excess, lactate and pH predicting 72-h mortality of multiple trauma

Objective

To compare the predictive values of base excess (BE), lactate and pH of admission arterial blood gas for 72-h mortality in patients with multiple trauma.

Methods

This was a secondary analysis based on a publicly shared trauma dataset from the Dryad database, which provided the clinical data of 3669 multiple trauma patients with ISS > = 16. The records of BE, lactate, pH and 72-h prognosis data without missing values were selected from this dataset and 2441 individuals were enrolled in the study. Logistic regression model was performed to calculate the odds ratios (ORs) of variables. Area under the curve (AUC) of receiver operating curve (ROC) was utilized to evaluate the predictive value of predictors for 72 h in-hospital mortality. Pairwise comparison of AUCs was performed using the Delong’s test.

Results

The statistically significant correlations were observed between BE and lactate (r = − 0.5861, p < 0.05), lactate and pH (r = − 0.5039, p < 0.05), and BE and pH (r = − 0.7433, p < 0.05). The adjusted ORs of BE, lactate and pH for 72-h mortality with the adjustment for factors including gender, age, ISS category were 0.872 (95%CI: 0.854–0.890), 1.353 (95%CI: 1.296–1.413) and 0.007 (95%CI: 0.003–0.016), respectively. The AUCs of BE, lactate and pH were 0.693 (95%CI: 0.675–0.712), 0.715 (95%CI: 0.697–0.733), 0.670 (95%CI: 0.651–0.689), respectively.

Conclusions

There are significant correlations between BE, lactate and pH of the admission blood gas, all of them are independent predictors of 72-h mortality for multiple trauma. Lactate may have the best predictive value, followed by BE, and finally pH.

Biochemical Effects of Routine Gonadectomy on Blood of Domestic Ferrets (Mustela putorius furo)

We studied domestic ferrets (Mustela putorius furo) to evaluate the physiologic effects of routine surgery. Standard plasma biochemistry panels and ¹H-NMR spectroscopy of heparinized whole blood were performed on samples taken 24 h prior to and immediately after surgery from female and male ferrets undergoing routine gonadectomy. Increases in plasma glucose, phosphorus, potassium, and creatine kinase concentrations associated with the duration of surgery were identified on plasma biochemistry panels. Whole-blood NMR spectra allowed us to identify 42 metabolites and one drug residue. Variations between pre- and postoperative metabolite concentrations were most pronounced for female ferrets, which underwent more prolonged surgery than males. Affected metabolites included organic acids and osmolytes (betaine, methylmalonate, <small>D</small>-lactate), fatty acids and lipids (2-hydroxy-3-methylbutyric acid), and amino acid groups (acetylglycine, alloisoleucine, leucine, and isoleucine). These findings indicate that ¹H-NMR spectroscopy of whole blood provides insight into metabolic perturbations in domestic ferrets undergoing surgery that are not detected in routine clinical chemistry panels.

Trauma severity associated with stress index in emergency settings: an observational prediction-and-validation study

Aim

Early judgments for treating severe trauma patients are essential for life‐saving. Stress index (SI), obtained from a division of blood glucose level by serum potassium at arrival, might be useful for early prediction. However, the efficacy of SI was unknown. The purpose of this study was to identify and validate prediction models of severe trauma (ST) and the need for damage control operation (DCOP) and massive transfusion (MT) by using SI among trauma patients.

Methods

This study was a retrospective and prospective observational study. The prediction models were created by 1‐year retrospective data of 167 trauma patients. The prediction models were validated by 6 months of prospective data of 87 trauma patients.

Results

The prediction model for ST contained respiratory rate and SI as significant factors. The prediction model for DCOP contained SI. The prediction model for MT contained systolic blood pressure and SI. The correlation of probability of MT, ST, and DCOP was r = 0.70 (P < 0.001), r = 0.46 (P < 0.001), and r = 0.15 (P = 0.196), respectively. The predicted probability of MT, ST, and DCOP showed 0.93 (95% confidence interval [CI], 0.88–0.90) and 0.80 (95% CI, 0.74–0.86), and 0.79 (95% CI, 0.70–0.88).

Conclusion

We identified and validated our prediction models for ST and the need for DCOP and MT among trauma patients using SI as a main predictor. Our models indicated that fewer variables in an early phase of the treatment process can inform clinicians regarding how severe a patient is and which intervention is needed.

A Comparative Study of Injury Severity Scales as Predictors of Mortality in Trauma Patients: Which Scale Is the Best?

Objective:

To compare the injury severity scales as predictors of mortality in trauma patients to search for the best scale.

Methods:

In a prospective cohort study and systematical random sampling conducted from March to September 2017, trauma patients over the age of 13 years were enrolled. The investigated variables were age, gender, systolic blood pressure, heart rate, respiratory rate, injured body region, Glasgow Coma Scale (GCS), injury severity score (ISS), revised trauma score (RTS), trauma injury severity score (TRISS) and the outcome.

Results:

Totally, 1410 trauma patients were followed up, out of which 68.5% were male. The participants’ mean age was 43.5±20.88 years. After adjusting the confounding effects, age over 60 years (OR=7.38, CI [3.91-13.93]), GCS<8 (OR=6.5, CI [2.38-18.16]), RTS<7.6 (OR=6.04, CI [2-13.7]), and TRISS<0.9 (OR=3.09, CI [1.39-6.88]) were determined as the most significant predictor variables for in-hospital mortality. The results of Receiver Operating Characteristic (ROC) curve revealed that TRISS had the highest area under the curve in comparison to other tests that were evaluated. Furthermore, TRISS had the highest sensitivity and specificity for scores higher than 96.15. By contrast, the sensitivity and specificity of GCS decreased for scores higher than 5.5.

Conclusion:

Our results showed that TRISS, RTS, GCS, and ISS were all very effective approaches for evaluating prognosis, mortality and probable complications in trauma patients; thus, these systems of injury evaluation and scoring are recommended to facilitate treatment. TRISS, RTS, and ISS had almost the same sensitivity that was higher than GCS, but GCS had the most specificity. Finally, TRISS was selected as the most efficient scale for predicting mortality.

Assessment of the Initial Risk Factors for Mortality among Patients with Severe Trauma on Admission to the Emergency Department

Background

For decades, trauma has been recognized globally as a major cause of death. Reducing the mortality of patients with trauma is an extremely pressing issue, particularly for those with severe trauma. An early and accurate assessment of the risk of mortality among patients with severe trauma is important for improving patient outcomes.

Methods

We performed a retrospective medical record review of 582 patients with severe trauma admitted to the emergency department between July 2011 and June 2016. We analyzed the associations of in-hospital mortality with the baseline characteristics and initial biochemical markers of patients with severe trauma on admission.

Results

The overall in-hospital mortality rate was 14.9%. Multivariate logistic regression analysis showed that the patient’s Rapid Emergency Medicine Score (REMS; odds ratio [OR], 1.186; 95% confidence interval [CI], 1.018–1.383; p=0.029), Emergency Trauma Score (EMTRAS; OR, 2.168; 95% CI, 1.570–2.994; p<0.001), serum lactate levels (SLL; OR, 1.298; 95% CI, 1.118–1.507; p<0.001), and Injury Severity Score (ISS; OR, 1.038; 95% CI, 1.010–1.130; p=0.021) were significantly associated with in-hospital mortality.

Conclusion

The REMS, EMTRAS, and SLL can easily and rapidly be used as alternatives to the injury severity score to predict in-hospital mortality for patients who present to the emergency department with severe trauma.

The impact of admission serum lactate on children with moderate to severe traumatic brain injury

Background

Lactate is used to evaluate the prognosis of adult patients with trauma. However, the prognostic significance of admission serum lactate in the setting of pediatric traumatic brain injury (TBI) is still unclear. We aim to investigate the impact of admission lactate on the outcome in children with moderate to severe TBI.

Methods

This retrospective study was conducted in a tertiary pediatric hospital between May 2012 and Jun 2018 included children with an admission Glasgow Coma Scale (GCS) of ≤13. Two hundred and thirteen patients were included in the analysis and 45 patients died in hospital.

Results

Admission lactate and glucose were significantly higher in non-survivors than those in survivors (P < 0.05). Admission lactate was positively correlated with admission glucose and negatively correlated with GCS in all patients (n = 213), subgroup of isolated TBI (n = 112) and subgroup of GCS ≤ 8 (n = 133), respectively. AUCs of lactate could significantly predict the mortality and were higher than those of glucose in all patients, subgroup of isolated TBI and subgroup of GCS ≤ 8, respectively. Multivariate logistic regression showed that admission lactate (Adjusted OR = 1.189; 95% CI: 1.002–1.410; P = 0.047) was independently associated with mortality, while admission glucose (Adjusted OR = 1.077; 95% CI: 0.978–1.186; P = 0.133) wasn’t an independent risk factor of death. Elevated admission lactate (> 2 mmol/L) was associated with death, reduced 14-day ventilation-free days, 14-day ICU-free days and 28-day hospital-free days.

Conclusions

Admission serum lactate can effectively predict the mortality of children with moderate to severe TBI. Elevated admission lactate is associated with death, reduced ventilator-free, ICU-free, and hospital-free days. Admission serum lactate could be used as a prognostic biomarker of mortality in children with moderate to severe TBI.

Prognostic Value of Blood Lactate and Lactate Clearance in Refractory Cardiac Arrest Treated by Extracorporeal Life Support

OBJECTIVE

During cardiac arrest (CA) resuscitation, an 'ischaemia-reperfusion' syndrome occurs leading to multiorgan failure reflected by an increase in blood lactate. Blood lactate is a diagnosis and prognosis biomarker in extracorporeal life support (ECLS), but its kinetic appears more informative to assess a patient's outcome. The aim of the present study was to describe the prognostic value of blood lactate and lactate clearance (LC) 3 (H3) and 6 h (H6) after the initiation of ECLS in the treatment of refractory CA.

METHODS

Patients admitted to the intensive care unit for refractory CA were included. Lactate measurements were performed at the initiation of ECLS (H0) and at H3 and H6 upon the initiation of ECLS. LC was measured from 0 to 3 h (LC03), 0 to 6 h (LC06) and 3 to 6 h (LC36). The primary endpoint was in-hospital mortality within 28 days.

RESULTS

Sixty-six patients were enrolled in the study. Lactate levels were higher in deceased patients. Increased mortality was observed with increasing levels of lactate at H3 and H6 and with decreasing LC03. Using logistic regression, an association was observed between mortality and lactate at H3 with an odds ratio (OR) of 1.21 (95% confidence interval (CI) 1.05-1.42); LC03, OR of 0.93 (95% CI 0.87-0.99) and LC06, OR of 0.96 (95% CI 0.92-0.99).

CONCLUSION

Blood lactate and LC within the first 3 h of ECLS in refractory CA are associated with mortality. LC is a more relevant parameter than blood lactate, taking into account both the production and elimination of lactate. We suggest to preferentially use LC to assess the patient's outcome.

Early Risk Score for Predicting Hypotension in Normotensive Patients with Non-Variceal Upper Gastrointestinal Bleedin

Risk assessment for upper gastrointestinal bleeding (UGIB) is important; however, current scoring systems are insufficient. We aimed to develop and validate a prediction model for rapidly determining the occurrence of hypotension in non-variceal UGIB patients with normotension (systolic blood pressure ≥90 mmHg) at emergency department presentation. In this prospective observational cohort study, consecutive non-variceal UGIB patients between January 2012 and April 2017 were enrolled. We developed and validated a new prediction model through logistic regression, with the occurrence of hypotension <24 h as the primary outcome. Among 3363 UGIB patients, 1439 non-variceal UGIB patients were included. The risk factors for the occurrence of hypotension were lactate level, blood in nasogastric tube, and systolic blood pressure. The area under the curve (AUC) of the new scoring model (LBS—Lactate, Blood in nasogastric tube, Systolic blood pressure) in the development cohort was 0.74, higher than the value of 0.64 of the Glasgow–Blatchford score for predicting the occurrence of hypotension. The AUC of the LBS score in the validation cohort was 0.83. An LBS score of ≤2 had a negative predictive value of 99.5% and an LBS score of ≥7 had a specificity of 97.5% in the validation cohort. The new LBS score stratifies normotensive patients with non-variceal UGIB at risk for developing hypotension.

Predictive Value of Point-of-care Lactate Measurement in Patients Meeting Level II and III Trauma Team Activation Criteria that Present to the Emergency Department: A Prospective Study

Background

The aim of this study was to investigate the utility of early point-of-care (POC) lactate levels to help predict injury severity and ultimate emergency department (ED) disposition for trauma patients meeting Level II and III activation criteria.

Methods

This was a blinded, prospective cohort study including a convenience sample of patients meeting our triage criteria for Level II or III team activation with stable vital signs. Bedside lactate samples were collected during the secondary survey. Clinical care/disposition was at the discretion of physicians who remained blinded to the bedside lactate result. An elevated lactate was defined as >2.0 mmol/L.

Results

Ninety-six patients were in the study group; mean age was 41 ± 17 years, 26% were female, 57% were Hispanic, and 60% admitted. We found no difference in initial mean POC lactate levels (mmol/L) for admitted versus discharged groups and Injury Severity Score (ISS) ≥9 versus ISS <9 groups (3.71 [95% confidence interval (CI): 3.1-4.4] vs. 3.85 [95% CI: 2.8-4.9]; P = 0.99 and 3.54 [95% CI: 2.7-4.4] vs. 3.89 [95% CI: 3.1-4.6]; P = 0.60, respectively). Performance characteristics of early elevated lactate levels were poor both to predict need for hospital admission (sensitivity = 77% [65%-87%]; specificity = 26% [13%-43%]; negative predictive value [NPV] = 43% [27%-61%]; and positive predictive value [PPV] = 62% [56%-67%]) and to identify patients with ISS scores ≥9 (sensitivity = 76% [59%-89%]; specificity = 24% [14%-37%]; NPV = 65% [47%-80%]; and PPV = 36% [30%-41%]).

Conclusions

For Level II/III, we found that early bedside lactate levels were not predictive of ISS ≥9 or the need for admission.

Level of Evidence

III (diagnostic test).

Prognostic value of 2-hour lactate level and lactate clearance for 30-day mortality and comparison with trauma scores in multi-trauma patients

Objective:

Trauma scores are prone to misreading. Therefore, a readily available, objective way to estimate the mortality of the trauma patients is needed. We aimed to evaluate the prognostic utility of lactate levels, and clearance for 30-days mortality, and compare with the physiological trauma scores.

Methods:

All adult trauma patients (two hundred) admitted to ED were enrolled. Initial and 2-hour serum lactate levels were measured and components of GAP, MGAP, RTS, VIEWS and VIEWS-L trauma scores were calculated.

Results:

Final study population was 200 patients with a median age of 33 years. Mortality was 7/200 (3.5%) in 30-days. Both initial (2.3 vs. 7.7 mmol/L) and 2h-lactate (1.7 vs. 8.4 mmol/L) levels were significantly lower, and lactate clearance was significantly higher (23.8% vs. -12.0%) in survivors. Also, the change in the lactate level from 0h to 2h (2.3 vs. 1.7mmol/L) was significant in survivors, contrary to non-survivors (7.7 vs. 8.4mmol/L). VIEWS-L, VIEWS, two hour-lactate level and EMTRAS showed high specificity at the 100% sensitivity cut-offs, therefore, were the most valuable prognostic parameters in this study.

Conclusion:

Calculation of 2h-lactate clearance and evaluation of a 2h-lactate level may not be needed to predict long-term mortality if the initial lactate level is below 2.8mmol/L.

Clinical value of triage lactate in risk stratifying trauma patients using interval likelihood ratios

Emergency physicians face the challenge of rapidly identifying high-risk trauma patients. Lactate (LAC) is widely used as a surrogate of tissue hypoperfusion. However, clinically important values for LAC as a predictor of mortality are not well defined.

OBJECTIVES

1. To assess the value of triage LAC in predicting mortality after trauma. 2. To compute interval likelihood ratios (LR) for LAC.

METHODS

Retrospective chart review of trauma patients with a significant injury mechanism that warranted labs at an urban trauma center.

OUTCOME

In-hospital mortality. Data are presented as median and quartiles or percentages with 95% confidence intervals. Groups (lived vs. died) were compared with Man-Whitney-U or Fisher's-exact test. Multivariate analysis was used to measure the association of the independent variables and mortality. The interval likelihood ratios were calculated for all LAC observed values.

RESULTS

10,575 patients; median age: 38 [25-57]; 69% male; 76% blunt; 1.1% [n=119] mortality. LAC was statistically different between groups in univariate (2.3 [1.6,3.0] vs 2.8 [1.6,4.8], p=0.008) and multivariate analyses (odds ratio: 1.14 [1.08-1.21], p=0.0001). Interval ratios for LR- ranged from 0.6-1.0. Increasing LAC increased LR+. However, LR+ for LAC reached 5 with LAC>9mmol/L and passed 10 (moderate and conclusive increase in disease probability, respectively) with LAC>18mmol/L.

CONCLUSIONS

In a cohort of trauma patients with a wide spectrum of characteristics triage LAC was statistically able to identify patients at high risk of mortality. However, clinically meaningful contribution to decision-making occurred only at LAC>9. LAC was not useful at excluding those with a low risk of mortality.

Biochemical Markers as Predictors of In-Hospital Mortality in Patients with Severe Trauma: A Retrospective Cohort Study

Background

Initial evaluation of injury severity in trauma patients is an important and challenging task. We aimed to assess whether easily measurable biochemical parameters (hemoglobin, pH, and prothrombin time/international normalized ratio [PT/INR]) can predict in-hospital mortality in patients with severe trauma.

Methods

This retrospective study involved review of the medical records of 315 patients with severe trauma and an injury severity score >15 who were managed at Gyeongsang National University Hospital between January 2005 and December 2015. We extracted the following data: in-hospital mortality, injury severity score, and initial hemoglobin level, pH, and PT/INR. The predictive values of these variables were compared using receiver operation characteristic curves.

Results

Of the 315 patients, 72 (22.9%) died. The in-hospital mortality rates of patients with hemoglobin levels <8.4 g/dl and ≥8.4 g/dl were 49.8% and 9.9%, respectively (P < 0.001). At a cutoff hemoglobin level of 8.4 g/dl, the sensitivity and specificity values for mortality were 81.9% and 86.4%, respectively. At a pH cutoff of 7.25, the sensitivity and specificity values for mortality were 66.7% and 77.8%, respectively; 66.7% of patients with a pH <7.25 died versus 22.2% with a pH ≥7.25 (P < 0.001). The in-hospital mortality rates for patients with PT/INR values ≥1.4 and <1.4 were 37.5% and 16%, respectively (P < 0.001; sensitivity, 37.5%; specificity, 84%).

Conclusions

Using the suggested cutoff values, hemoglobin level, pH, and PT/INR can simply and easily be used to predict in-hospital mortality in patients with severe trauma.

Continuous and simultaneous determination of venous blood metabolites

Metabolic syndrome is associated with cardiovascular disease, type 2 diabetes mellitus (T2DM) and prediabetes. Metabolic syndrome is a cluster of interrelated clinical disorders. Difficulties in regulating glucose levels in blood are implicated in many of these disorders. Lactate, another energy metabolite, is produced under anaerobic conditions and can be used to monitor the balance between aerobic and anaerobic metabolism. Tested together, these metabolite levels can provide pro-diagnostic information that improves patient outcomes. Glucose and lactate were determined continuously and simultaneously in whole blood using a dual-channel thermal biosensor device in which one channel employed glucose oxidase for glucose analysis in comparison with lactate oxidase for lactate analysis in the others. No detectable clogging or interference was observed using venous blood samples. The linear detection range for both the glucose and lactate assays was 0.5-45mM. The sampling rate of up to 24 samples per hour with assay cycle time of 2.5min was achieved. Comparative analysis between our device and the HemoCue method showed an excellent correlation. The device was stable for hundreds of injections over a period of 45 days. The broad linear range, fast response and detection sensitivity are satisfactory for the clinical requirements, e.g. for diabetic or cardiovascular patients in intensive care units or surgical operation, where the tight control of blood glucose can decrease morbidity or mortality.

Agreement between arterial and venous lactate in emergency department patients: a prospective study of 157 consecutive patients

INTRODUCTION

In the emergency department (ED), lactate is routinely used for risk stratification. Whether venous or arterial lactate measured on blood gas is interchangeable is not known. We hypothesized that venous lactate can be used instead of arterial lactate for the evaluation of acute patients in the ED.

PATIENTS AND METHODS

This was a prospective single-center study. All patients requiring a lactate measurement were enrolled and we simultaneously drew arterial and venous blood. We followed up all patients to hospital discharge. Our primary aim was to evaluate agreements between the two measurements using Bland and Altman plots with the report of bias (mean difference) and limits of agreements. We also aimed to determine the rate of misclassification (defined as one measurement<1.8 mmol/l and the other>2.2). Our secondary aim was to evaluate their respective prognostic value to predict in-hospital death or admission in the ICU longer than 72 h.

RESULTS

The mean age of the 132 analyzed patients was 62 years (SD: 18 years), and 59% were men. The mean difference (bias) between arterial and venous lactate was -0.6 mmol/l (limits of agreement: -1.7 to 0.6 mmol/l). The rate of misclassification was 8% (95% confidence interval: 3-2%). Both methods present similar performances for the prediction of poor outcomes, with an area under the receiving operator characteristic curves of 0.67 for both. Results were similar when focused only on septic patients.

CONCLUSION

Venous and arterial lactates do not agree well, and there is a high misclassification rate. Venous lactate does not appear to be interchangeable with arterial sampling.

The predictive value of initial serum lactate in trauma patients

Trauma patients require early assessment of injury severity. Trauma scores, although well validated, can be unwieldy in the emergency clinical setting. We sought to evaluate the prognostic value of initial serum lactate (ISL) for mortality, operative intervention (OI), and intensive care unit admission (ICUA) in trauma patients. We conducted an institutional review board-approved retrospective study. We reviewed all trauma patients between January 2007 and June 2012 in our prospectively maintained database. We included only adults whose ISL had been drawn within the first 35 min after arrival. We included only those patients whose interval between injury and arrival was within 24 h. Survivors and nonsurvivors were compared using logistic regression, Mann-Whitney U, and chi-square tests. Discriminating ability of ISL for mortality was assessed with receiver operating characteristic analysis. Our secondary outcomes (ICUA and OI) were evaluated with logistic regression test and receiver operating characteristic analysis. A total of 1,941 patients were included. Overall mortality was 6.2%. Median ISL was 32 mg/dL (interquartile range, 17 - 62) for nonsurvivors versus 21 mg/dL (interquartile range, 14 - 32) for survivors (P < 0.001). In multivariate analysis, ISL was a significant covariate for mortality (P = 0.015). The odds ratio was 1.010 (95% confidence interval, 1.002 - 1.019). The area under the curve was 0.63. The ISL was a significant covariate for OI (P = 0.033). The ISL did not reach significance for ICUA. The ISL is an easily measured, rapid, and inexpensive test that can help to quickly stratify injury severity in trauma patients. We have found that ISL, when used in strictly selected patients, can predict OI and mortality.

Serum interleukin-6 level as an early marker of injury severity in trauma patients in an urban low-income setting: a cross-sectional study

Background

Trauma is still the leading cause of death in many regions of the world. Severity scores have been developed to assist in management of trauma victims. Immune response to trauma has been known to positively correspond to the severity of trauma. Part of this response involves release of cytokines into blood circulation which promote the acute inflammatory response commonly seen after trauma. Studies have shown that IL-6 levels commonly correlate positively with the Injury Severity Score (ISS). The aim of this cross-sectional study was to determine whether this kind of relationship exists between IL-6 levels and injury severity in trauma patients in Mulago Hospital as defined by the Kampala Trauma Score (KTSII) which is locally developed.

Methods

Trauma patients aged ≥18 years presenting to the Accident and Emergency unit of Mulago National Referral Hospital (MNRH) within 12 h after injury were recruited into the study after obtaining consent. Severity of injury was determined as per the Kampala Trauma Score (KTSII) and venous blood drawn for assay of serum IL-6 levels. Data obtained was entered and analyzed using Stata version 11 software focusing on the association between Serum IL-6 levels with Severity of trauma and duration of injury.

Results

A total of 159 patients were recruited (79 Mild and 80 Severe trauma) with a male to female ratio of 4.7:1. Road traffic crashes (67.92 %) were the commonest cause of injury. Serum IL-6 levels were found to positively correspond with severity of injury (z = 4.718, p < 0.001). There was no significant correlation between serum IL-6 levels and duration of injury in both severe (r = 0.12, p = 0.29) and mild (r = 0.06, p = 0.62) trauma groups of patients. Only 9.43 % of trauma patients were brought in an Ambulance.

Conclusions

Serum IL-6 levels correspond with severity of injury. However, within the first twelve hours after injury, these levels did not vary significantly with duration of injury.

Factors affecting morbidity and mortality in traumatic colorectal injuries and reliability and validity of trauma scoring systems

Background and aim

This study aims to determine the factors that affect morbidity and mortality in colon and rectum injuries related with trauma, the use of trauma scoring systems in predicting mortality and morbidity.

Patients and methods

Besides patient demographic characteristics, the mechanism of injury, the time between injury and surgery, accompanying body injuries, admittance Glasgow coma scale (GCS), findings at surgery and treatment methods were also recorded. With the obtained data, the abbreviated injury scale (AIS), injury severity score (ISS), revised trauma score (RTS) and trauma-ISS (TRISS) scores of each patient were calculated by using the 2008 revised AIS.

Results

Of the patients, 172 (88.7 %) were male, 22 (11.3 %) were female and the mean age was 29.15 ± 12.392 (15–89) years. The morbidity of our patients were 32 % and mortality were 12.4 %. ISS (p < 0.001), RTS (p < 0.001), and the TRISS (p < 0.001) on mortality were found to be significant. TRISS (p = 0.008), the ISS (p < 0.001), the RTS (p = 0.03), the trauma surgery interval (TSI, p < 0.001) were observed to have significant effects on morbidity.

Regression analysis showed that the ISS (OR 1.1; CI 95 % 1.01–1.2; p = 0.02), the RTS (OR 0.37; CI 95 % 0.21–0.67; p = 0.001) had significant effects on mortality. While the effects of TSI (OR 5.3; CI 95 % 1.5–18.8; p = 0.01) on morbidity were found to be significant.

Conclusion

Predicting mortality by using scoring systems and close postoperative follow up of patients in the risk group may ensure decreases in the rates of morbidity and mortality.

Utility of admission serum lactate in pediatric trauma

BACKGROUND/PURPOSE

Serum lactate measurement has a predictive value in adult trauma. To date, there has been no prospective analysis of the predictive value of admission serum lactate in pediatric trauma.

METHODS

Admission serum lactate was prospectively measured over a two year period on all children under age 15 years who met trauma alert criteria at an urban Level 1 trauma center. Elevated serum lactate (>2.0 mmol/L) was correlated with Injury Severity Scores (ISS), injury types, and hospital outcomes.

RESULTS

A total of 277 injured children with admission lactate measurements were evaluated. Patients with elevated lactate had higher mean ISS than those with normal lactate (12.8 vs. 5.1, p<0.01), and increased need for intubation, major procedures and ICU admission. Elevated lactate was associated with low specificity (54.4%), moderate sensitivity (86.7%) and high negative predictive value (94.5%) for detecting injury (ISS>15). Lactate measurements over 4.7 mmol/L were highly specific (95.8%) for injury.

CONCLUSIONS

Elevated admission venous lactate level is associated with injury and outcomes, but lacks adequate sensitivity and specificity. Lactate over 4.7 mmol/L is strongly suggestive of severe injury, while lactate below 2.0 mmol/L is reassuring for not having injury. Lactates between 2.0 and 4.7 mmol/L remain indeterminate in predictive potential for injury or outcomes.

Serum lactate as a predictor of early outcomes among trauma patients in Uganda

Background

Trauma is the leading cause of death in the developed world. Accurate assessment of severity of injuries is critical in informing treatment choices. Current models of assessing severity of injury are not without limitations. The objective of this study therefore was to determine the diagnostic accuracy of serum lactate assays in assessing injury severity and prediction of early outcomes among trauma patients.

Methods

This was a cross-sectional analytical study. Consecutive series of all eligible patients had a single venous blood sample drawn for lactate assay analysis (index test) and a concurrent Kampala Trauma Score (KTS) II value determination (reference test). Admitted patients were followed up to assess early outcomes (length of hospital stay and mortality).

Results

Out of the 502 trauma patients recruited, 108 (22%) were severely injured, 394 (78%) had non-severe injuries, and 183 were admitted. There was a significant difference between median (interquartile range (IQR)) lactate levels among the severely injured (4.3 (2.6, 6.6)) and the non-severely injured (2.4 (1.6, 3.5), p < 0.001). After a 72-h follow-up of the admitted patients, 102 (56%) were discharged, 61 (33%) remained in the hospital, 3 (2%) remained in the ICU, and 17 (3%) had died. The area under the receiver operator characteristic (ROC) curve was 0.75 for injury severity. Serum lactate ≥2.0 mmol/l had a hazard ratio of 1.10 (p < 0.001) for emergency department disposition, 4.33 (p = 0.06) for the 72-h non-discharge disposition, and 1.19 (p < 0.001) for 72-h mortality. Serum lactate ≥2.0 mmol/l at admission was useful in discriminating severe from non-severe injuries with a sensitivity of 88%, specificity of 38%, PPV of 30%, and NPV of 92%.

Conclusion

Hyperlactatemia in an emergency trauma patient suggests a high probability of severe injury.

Potential early predictors for outcomes of experimental hemorrhagic shock induced by uncontrolled internal bleeding in rats

Uncontrolled hemorrhage, resulting from traumatic injuries, continues to be the leading cause of death in civilian and military environments. Hemorrhagic deaths usually occur within the first 6 hours of admission to hospital; therefore, early prehospital identification of patients who are at risk for developing shock may improve survival. The aims of the current study were: 1. To establish and characterize a unique model of uncontrolled internal hemorrhage induced by massive renal injury (MRI), of different degrees (20-35% unilateral nephrectomy) in rats, 2. To identify early biomarkers those best predict the outcome of severe internal hemorrhage. For this purpose, male Sprague Dawley rats were anesthetized and cannulas were inserted into the trachea and carotid artery. After abdominal laparotomy, the lower pole of the kidney was excised. During 120 minutes, hematocrit, pO₂, pCO₂, base excess, potassium, lactate and glucose were measured from blood samples, and mean arterial pressure (MAP) was measured through arterial tracing. After 120 minutes, blood loss was determined. Statistical prediction models of mortality and amount of blood loss were performed. In this model, the lowest blood loss and mortality rate were observed in the group with 20% nephrectomy. Escalation of the extent of nephrectomy to 25% and 30% significantly increased blood loss and mortality rate. Two phases of hemodynamic and biochemical response to MRI were noticed: the primary phase, occurring during the first 15 minutes after injury, and the secondary phase, beginning 30 minutes after the induction of bleeding. A Significant correlation between early blood loss and mean arterial pressure (MAP) decrements and survival were noted. Our data also indicate that prediction of outcome was attainable in the very early stages of blood loss, over the first 15 minutes after the injury, and that blood loss and MAP were the strongest predictors of mortality.

Even mild hyperlactatemia is associated with increased mortality in critically ill patients

Introduction

The clinical significance of elevation of lactate levels within the reference range is not well studied. The objective of this study was to determine the best cutoff threshold for serum lactate within the reference range (0.01 to 2.00 mM) that best discriminated between survivors and nonsurvivors of critical illness and to examine the association between relative hyperlactatemia (lactate above the identified threshold) and mortality.

Methods

This was a retrospective cohort study of adult patients admitted to the medical-surgical intensive care unit (ICU) of a tertiary care academic center. Youden index was calculated to identify the best lactate cutoff threshold that discriminated between survivors and nonsurvivors. Patients with lactate above the identified threshold were defined as having relative hyperlactatemia. Multivariate logistic regression, adjusting for baseline variables, was performed to determine the relationship between the above two ranges of lactate levels and mortality. In addition, a test of interaction was performed to assess the effect of selected subgroups on the association between relative hyperlactatemia and hospital mortality.

Results

During the study period, 2,157 patients were included in the study with mean lactate of 1.3 ± 0.4 mM, age of 55.1 ± 20.3 years, and acute physiology and chronic health evaluation (APACHE) II score of 22.1 ± 8.2. Vasopressors were required in 42.4%. Lactate of 1.35 mM was found to be the best cutoff threshold for the whole cohort. Relative hyperlactatemia was associated with increased hospital mortality (adjusted odds ratio (aOR), 1.60, 95% confidence interval (CI) 1.29 to 1.98), and ICU mortality (aOR, 1.66; 95% CI, 1.26 to 2.17) compared with a lactate level of 0.01 to 1.35 mM. This association was consistent among all examined subgroups.

Conclusions

Relative hyperlactatemia (lactate of 1.36 to 2.00 mM) within the first 24 hours of ICU admission is an independent predictor of hospital and ICU mortality in critically ill patients.

Systematic review of predictive performance of injury severity scoring tools

Many injury severity scoring tools have been developed over the past few decades. These tools include the Injury Severity Score (ISS), New ISS (NISS), Trauma and Injury Severity Score (TRISS) and International Classification of Diseases (ICD)-based Injury Severity Score (ICISS). Although many studies have endeavored to determine the ability of these tools to predict the mortality of injured patients, their results have been inconsistent. We conducted a systematic review to summarize the predictive performances of these tools and explore the heterogeneity among studies. We defined a relevant article as any research article that reported the area under the Receiver Operating Characteristic curve as a measure of predictive performance. We conducted an online search using MEDLINE and Embase. We evaluated the quality of each relevant article using a quality assessment questionnaire consisting of 10 questions. The total number of positive answers was reported as the quality score of the study. Meta-analysis was not performed due to the heterogeneity among studies. We identified 64 relevant articles with 157 AUROCs of the tools. The median number of positive answers to the questionnaire was 5, ranging from 2 to 8. Less than half of the relevant studies reported the version of the Abbreviated Injury Scale (AIS) and/or ICD (37.5%). The heterogeneity among the studies could be observed in a broad distribution of crude mortality rates of study data, ranging from 1% to 38%. The NISS was mostly reported to perform better than the ISS when predicting the mortality of blunt trauma patients. The relative performance of the ICSS against the AIS-based tools was inconclusive because of the scarcity of studies. The performance of the ICISS appeared to be unstable because the performance could be altered by the type of formula and survival risk ratios used. In conclusion, high-quality studies were limited. The NISS might perform better in the mortality prediction of blunt injuries than the ISS. Additional studies are required to standardize the derivation of the ICISS and determine the relative performance of the ICISS against the AIS-based tools.

Diabetes and fracture healing: the skeletal effects of diabetic drugs

INTRODUCTION

Over 39,000 diabetic patients are surgically treated for trauma and orthopaedic injuries annually in the UK, yet the effects of diabetic medications on the skeletal system is an under researched and under acknowledged field.

AREAS COVERED

This review covers all English language novel experimental data reports investigating the effects of the main classes of diabetic drugs on the skeletal system, specifically their effects on fracture healing, located through the literature search engines Medline and Web of Science.

EXPERT OPINION

Post-surgical gylcaemic control is paramount in insulin-controlled type 1 diabetic patients. Data on pharmacological control compounds used in type 2 diabetes are limited. Reports to date indicate thiazolidinediones to exert anti-osteogenic effects, in contrast to the observed osteogenic effects of biguanides. Ongoing research is desirable to guide future clinical recommendations.

Enzyme-based NAND gate for rapid electrochemical screening of traumatic brain injury in serum

We report on the development of a rapid enzyme logic gate-based electrochemical assay for the assessment of traumatic brain injury (TBI). The concept harnesses a biocatalytic cascade that emulates the functionality of a Boolean NAND gate in order to process relevant physiological parameters in the biochemical domain. The enzymatic backbone ensures that a high-fidelity diagnosis of traumatic brain injury can be tendered in a rapid fashion when the concentrations of key serum-based biomarkers reach pathological levels. The excitatory neurotransmitter glutamate and the enzyme lactate dehydrogenase were used here as clinically-relevant input TBI biomarkers, in connection to the low-potential detection of the NADH product in the presence of methylene green at a glassy carbon electrode. A systematic optimization of the gate and the entire protocol has resulted in the effective discrimination between the physiological and pathological logic levels. Owing to its robust design, the enzyme-based logic gate mitigates potential interferences from both physiological and electroactive sources and is able to perform direct measurements in human serum samples. Granted further detailed clinical validation, this proof-of-concept study demonstrates the potential of the electrochemical assay to aid in the rapid and decentralized diagnosis of TBI.