Diagnostic accuracy of a single point-of-care prehospital serum lactate for predicting outcomes in pediatric trauma patients

Lactate Levels as a Predictor of Emergency Department Revisits in Infants With Acute Bronchiolitis

OBJECTIVE

This study aimed to identify predictive biomarkers for unscheduled emergency department (ED) revisits within 24 hours of discharge in infants diagnosed with acute bronchiolitis (AB).

METHODS

A retrospective observational study was conducted on infants diagnosed with AB who visited 3 emergency medical centers between January 2020 and December 2022. The study excluded infants with comorbidities, congenital diseases, and prematurity and infants who revisited the ED after 24 hours of discharge. Demographic data, vital signs, and laboratory results were collected from the medical records. Univariable and multivariable logistic regression analyses were performed on factors with P of less than 0.1 in univariable analysis. Receiver operator curve analysis was used to assess the accuracy of lactate measurements in predicting ED revisits within 24 hours of discharge.

RESULTS

Out of 172 participants, 100 were in the revisit group and 72 in the discharge group. The revisit group was significantly younger and exhibited higher lactate levels, lower pH values, and higher pCO2 levels compared to the discharge group. Univariable logistic regression identified several factors associated with revisits. Multivariable analysis found that only lactate was a variable correlated with predicting ED revisits (odds ratio, 18.020; 95% confidence interval [CI], 5.764-56.334). The receiver operator curve analysis showed an area under the curve of 0.856, with an optimal lactate cutoff value of 2.15.

CONCLUSION

Lactate value in infants diagnosed with AB were identified as a potential indicator of predicting unscheduled ED revisits within 24 hours of discharge. The predictive potential of lactate levels holds promise for enhancing prognosis prediction, reducing health care costs, and alleviating ED overcrowding. However, given the study's limitations, a more comprehensive prospective investigation is recommended to validate these findings.

Predicting morbidity and mortality in Australian paediatric trauma with the Paediatric Age-Adjusted Shock Index and Glasgow Coma Scale

BACKGROUND

Paediatric age-adjusted shock index (SIPA) has emerged as a predictor of morbidity and mortality in trauma. Poor sensitivity and low generalisability demonstrated in previous studies have limited its use. We evaluate the use of SIPA in the general Australian paediatric trauma population and the combination of SIPA with GCS.

METHODS

All patients from January 2015 to August 2020 at a major Australian paediatric trauma centre were reviewed. Pre-arrival SIPA (pSIPA) and arrival SIPA (aSIPA) were calculated. If SIPA was elevated or the Glasgow Coma Scale ≤ 13, SIPA with mental state (SIPAms) was marked positive for pre-arrival (pSIPAms) and arrival (aSIPAms) respectively.

RESULTS/DISCUSSION

Data from 480 patients were analysed. pSIPA and aSIPA poorly predicted outcomes of morbidity. Only aSIPA predicted mortality. However, both pre-arrival and arrival SIPAms variables predict mortality, major trauma (ISS≥12), hospital LOS, need for ICU admission, and major surgery. Furthermore, median ISS and lactate were significantly higher in positive pSIPA, aSIPA, pSIPAms, and aSIPAms groups than negative. aSIPAms has a sensitivity of 76% and specificity of 70% for major trauma.

CONCLUSION

Broad inclusion criteria reduce SIPA's ability to predict morbidity. Combining it with GCS improves this and is most valuable when calculated at arrival. In addition, the score is more reliable for major trauma (ISS≥12). Future studies should evaluate the use of SIPAms in activation criteria.

Laboratory Markers in the Management of Pediatric Polytrauma: Current Role and Areas of Future Research

Severe trauma is the most common cause of mortality in children and is associated with a high socioeconomic burden. The most frequently injured organs in children are the head and thorax, followed by the extremities and by abdominal injuries. The efficient and early assessment and management of these injuries is essential to improve patients' outcome. Physical examination as well as imaging techniques like ultrasound, X-ray and computer tomography are crucial for a valid early diagnosis. Furthermore, laboratory analyses constitute additional helpful tools for the detection and monitoring of pediatric injuries. Specific inflammatory markers correlate with post-traumatic complications, including the development of multiple organ failure. Other laboratory parameters, including lactate concentration, coagulation parameters and markers of organ injury, represent further clinical tools to identify trauma-induced disorders. In this review, we outline and evaluate specific biomarkers for inflammation, acid-base balance, blood coagulation and organ damage following pediatric polytrauma. The early use of relevant laboratory markers may assist decision making on imaging tools, thus contributing to minimize radiation-induced long-term consequences, while improving the outcome of children with multiple trauma.

Risk Factors for Mortality in Neonatal Gastric Perforation: A Retrospective Cohort Study

Background: Neonatal gastric perforation is a rare but life-threatening issue. The aim of this study was to describe the clinical characteristics and prognosis of patients with neonatal gastric perforation and identify predictive factors for poor prognosis. Methods: This was a retrospective cohort study of patients with neonatal gastric perforation treated in a tertiary pediatric public hospital between April 2009 and October 2020. The enrolled patients were divided into survival and non-survival groups. Demographic information, clinical characteristics, laboratory and imaging features, and outcomes were collected from the electronic medical record. Univariate and multivariate logistic regression analyses were performed to obtain the independent factors associated with death risk. Additionally, we separated this population into two groups (pre-term and term groups) and explored the mortality predictors of these two groups, respectively. Results: A total of 101 patients with neonatal gastric perforation were included in this study. The overall survival rate was 70.3%. Seventy-one (70.3%) were pre-term neonates, and sixty-two (61.4%) were low-birth-weight neonates. The median age of onset was 3 days (range: 1-11 days). Abdominal distension [98 (97.0%) patients] was the most common symptom, followed by lethargy [78 (77.2%) patients], shortness of breath [60 (59.4%) patients] and vomiting [34 (33.7%) patients]. Three independent mortality risk factors were identified: shock (OR, 3.749; 95% CI, 1.247-11.269; p = 0.019), serum lactic acid > 2.5 mmol/L (5.346; 1.727-16.547; p = 0.004) and platelet count <150 × 10⁹/L (3.510; 1.115-11.053; p = 0.032). There was a borderline significant association between sclerema neonatorum and total mortality (4.827; 0.889-26.220; p = 0.068). In pre-term infants, serum lactic acid > 2.5 mmol/L and platelet count <150 × 10⁹/L remained independent risk factors for death. In term infants, the incidence of shock, coagulopathy, pH < 7.3, serum lactic acid > 2.5 mmol/L, and hyponatremia were statistically different between non-survival and survival groups. Conclusion: Shock, hyperlactatemia, and thrombocytopenia are independently associated with an increased risk of death in patients with neonatal gastric perforation. Identification of modifiable risk factors during the critical periods of life will contribute to the development of effective prevention and intervention strategies of neonatal gastric perforation.

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.

Handheld Tissue Oximetry for the Prehospital Detection of Shock and Need for Lifesaving Interventions: Technology in Search of an Indication?

Improved prehospital methods for assessing the need for lifesaving interventions (LSIs) are needed to gain critical lead time in the care of the injured. We hypothesized that threshold values using prehospital handheld tissue oximetry would detect occult shock and predict LSI requirements. This was a prospective observational study of adult trauma patients emergently transported by helicopter. Patients were monitored with a handheld tissue oximeter (InSpectra Spot Check; Hutchinson Technology Inc, Hutchinson, MN), continuous vital signs, and 21 laboratory measurements obtained both in the field with a portable analyzer and at the time of admission. Shock was defined as base excess ≥ 4 or lactate > 3 mmol/L. Eighty-eight patients were enrolled with a median Injury Severity Score of 16 (interquartile range, 5-29). The median hemoglobin saturation in the capillaries, venules, and arterioles (StO₂) value for all patients was 82% (interquartile range, 76%-87%; range, 42%-98%). StO₂ was abnormal (< 75%) in 18 patients (20%). Eight were hypotensive (9%) and had laboratory-confirmed evidence of occult shock. StO₂ correlated poorly with shock threshold laboratory values (r = -0.17; 95% confidence interval, -0.33 to 1.0; P = .94). The area under the receiver operating curve was 0.51 (95% confidence interval, 0.39-0.63) for StO₂ < 75% and laboratory-confirmed shock. StO₂ was not associated with LSI need on admission when adjusted for multiple covariates, nor was it independently associated with death. Handheld tissue oximetry was not sensitive or specific for identifying patients with prehospital occult shock. These results do not support prehospital StO₂ monitoring despite its inclusion in several published guidelines.

Is prehospital lactate testing useful in improving clinical assessment?

Introduction:

Lactate devices offer the potential for paramedics to improve patient triage and escalation of care for specific presentations. There is also scope to improve existing prehospital tools by including lactate measurement.

Method:

A literature search was conducted using the Medline, CINAHL, Academic Search Premier, Sciencedirect and Scopus databases.

Findings:

Acquiring prehospital lactate measurement in trauma settings improved triage and recognition of the need for critical care. Within a medical setting, studies offered mixed results in relating prehospital lactate measurement to diagnosis, escalating treatments and mortality. The accuracy of prehospital lactate measurements acquired varies, which could impact decision making.

Conclusion:

Prehospital lactate thresholds could aid decision making, although the literature is limited and evidence varies. Lactate values of ≥4 mmol/litre in medical and ≥2.5 mmol/litre in trauma patients could signify that care should be escalated to an appropriate facility, and that resuscitative measures should be initiated, particularly with sepsis, as reflected by standardised lactate values that guide treatment in hospitals. Similarly, a lactate value of <2 mmol/litre could mean de-escalating care into the community, although further research is warranted on this.

Error traps and culture of safety in pediatric trauma

Trauma is the leading cause of morbidity and mortality in the pediatric population. Due to a variety of factors, many pediatric trauma patients are initially evaluated and stabilized at adult hospitals that lack pediatric specific emergency medicine and surgical expertise. While similar to adult patients, the initial evaluation and resuscitation of pediatric patients does differ. Many of these key differences contribute to missed injury and susceptibility to error in the treatment of children. Here, we highlight a variety of differences between pediatric and adult trauma patients and clarify reasoning for these differences. Error traps that are discussed include missed cases of non-accidental trauma, missed blunt cerebrovascular injury, over use of CT (computed tomography) scans with unnecessary radiation exposure, missed small bowel or mesenteric injury, and unrecognized hemodynamic instability.

Compensatory Reserve Index: Performance of A Novel Monitoring Technology to Identify the Bleeding Trauma Patient

INTRODUCTION

Hemorrhage is one of the most substantial causes of death after traumatic injury. Standard measures, including systolic blood pressure (SBP), are poor surrogate indicators of physiologic compromise until compensatory mechanisms have been overwhelmed. Compensatory Reserve Index (CRI) is a novel monitoring technology with the ability to assess physiologic reserve. We hypothesized CRI would be a better predictor of physiologic compromise secondary to hemorrhage than traditional vital signs.

METHODS

A prospective observational study of 89 subjects meeting trauma center activation criteria at a single level I trauma center was conducted from October 2015 to February 2016. Data collected included demographics, SBP, heart rate, and requirement for hemorrhage-associated, life-saving intervention (LSI) (i.e., operation or angiography for hemorrhage, local or tourniquet control of external bleeding, and transfusion >2 units PRBC). Receiver-operator characteristic (ROC) curves were formulated and appropriate thresholds were calculated to compare relative value of the metrics for predictive modeling.

RESULTS

For predicting hemorrhage-related LSI, CRI demonstrated a sensitivity of 83% and a negative predictive value (NPV) of 91% as compared with SBP with a sensitivity to detect hemorrhage of 26% (P < 0.05) and an NPV of 78%. ROC curves generated from admission CRI and SBP measures demonstrated values of 0.83 and 0.62, respectively. CRI identified significant hemorrhage requiring potentially life-saving therapy more reliably than SBP (P < 0.05).

CONCLUSION

The CRI device demonstrated superior capacity over systolic blood pressure in predicting the need for posttraumatic hemorrhage intervention in the acute resuscitation phase after injury.

Early identification of trauma patients in need for emergent transfusion: results of a single-center retrospective study evaluating three scoring systems

BACKGROUND

The Trauma-Induced Coagulopathy Clinical Score (TICCS) was developed to be calculable on the site of injury to discriminate between trauma patients with or without the need for damage control resuscitation and thus transfusion. This early alert could then be translated to in-hospital parameters at patient arrival. Base excess (BE) and ultrasound (FAST) are known to be predictive parameters for emergent transfusion. We emphasize that adding these two parameters to the TICCS could improve the scoring system predictability.

METHODS

A retrospective study was conducted in the University Hospital of Liège. TICCS was calculated for every patient. BE and FAST results were recorded and points were added to the TICCS according to the TICCS.BE definition (+ 3 points if BE < - 5 and + 3 points in case of a positive FAST). Emergent transfusion was defined as the use of at least one blood product in the resuscitation room. The capacity of the TICCS, the TICCS.BE and the Trauma-Associated Severe Hemorrhage (TASH) to predict emergent transfusion was assessed.

RESULTS

A total of 328 patients were included. Among them, 14% needed emergent transfusion. The probability for emergent transfusion grows with the TICCS and the TICCS.BE values. We did not find a significant difference between the TICCS (AUC 0.73) and the TICCS.BE (AUC 0.76). The TASH proved to be more predictive (AUC 0.89). 66.6% of the patients with a TICCS ≥ 10 and 81.5% with a TICCS.BE ≥ 14 required emergent transfusion.

CONCLUSION

Adding BE and FAST to the original TICCS does not significantly improve the scoring system predictability. A prehospital TICCS > 10 could be used as a trigger for emergent transfusion activation. TASH could then be used at hospital arrival. Prehospital TASH calculation may be possible but should be further investigated.

LEVEL OF EVIDENCE

Diagnostic test, level III.

Prehospital Lactate Predicts Need for Resuscitative Care in Non-hypotensive Trauma Patients

Introduction

The prehospital decision of whether to triage a patient to a trauma center can be difficult. Traditional decision rules are based heavily on vital sign abnormalities, which are insensitive in predicting severe injury. Prehospital lactate (PLac) measurement could better inform the triage decision. PLac’s predictive value has previously been demonstrated in hypotensive trauma patients but not in a broader population of normotensive trauma patients transported by an advanced life support (ALS) unit.

Methods

This was a secondary analysis from a prospective cohort study of all trauma patients transported by ALS units over a 14-month period. We included patients who received intravenous access and were transported to a Level I trauma center. Patients with a prehospital systolic blood pressure ≤ 100 mmHg were excluded. We measured PLac’s ability to predict the need for resuscitative care (RC) and compared it to that of the shock index (SI). The need for RC was defined as either death in the emergency department (ED), disposition to surgical intervention within six hours of ED arrival, or receipt of five units of blood within six hours. We calculated the risk associated with categories of PLac.

Results

Among 314 normotensive trauma patients, the area under the receiver operator characteristic curve for PLac predicting need for RC was 0.716, which did not differ from that for SI (0.631) (p=0.125). PLac ≥ 2.5 mmol/L had a sensitivity of 74.6% and a specificity of 53.4%. The odds ratio for need for RC associated with a 1-mmol/L increase in PLac was 1.29 (95% confidence interval [CI] [0.40 – 4.12]) for PLac < 2.5 mmol/L; 2.27 (1.10 – 4.68) for PLac from 2.5 to 4.0 mmol/L; and 1.26 (1.05 – 1.50) for PLac ≥ 4 mmol/L.

Conclusion

PLac was predictive of need for RC among normotensive trauma patients. It was no more predictive than SI, but it has certain advantages and disadvantages compared to SI and could still be useful. Prospective validation of existing triage decision rules augmented by PLac should be investigated.

Prehospital point-of-care lactate following trauma: A systematic review

BACKGROUND

Serum lactate serves as a surrogate marker for global tissue hypoxia following traumatic injury and has potential to guide resuscitation. Portable, handheld point-of-care monitoring devices enable lactate values to be readily available in the prehospital environment. The current review examines the utility of prehospital lactate (pLa) measurement in the management of trauma.

METHODS

MEDLINE and EMBASE databases were searched using predefined criteria (pLa measurement, trauma patients) until March 10, 2016. Studies were examined for lactate measurement as an intervention, prognostic indicator, and utilization in the guidance of goal-directed therapy. The Newcastle-Ottawa Scale was used to assess risk of bias, and quality of evidence was evaluated using the Grading of Recommendations, Assessment, Development, and Evaluation system. Data were unsuitable for meta-analysis and are presented in narrative form.

RESULTS

Of 2,415 articles of interest, seven met the inclusion criteria, all of which were observational studies, including 2,085 trauma patients. Lactate sampling techniques, timings, and thresholds were heterogeneous. No studies used pLa to guide intervention. Elevated pLa may be an independent prognostic marker of critical illness in trauma patients, particularly in blunt trauma. Prehospital lactate measurement may be more sensitive than systolic blood pressure in determining need for resuscitative care. Early lactate measurement may be particularly useful in the detection of occult hypoperfusion, with elevated pLa detectable within 30 minutes of injury. All current studies were assessed as being of "low" or "very low" quality and were at risk of bias. Considerable logistical barriers to pLa measurement exist.

CONCLUSIONS

Prehospital point-of-care lactate monitoring for trauma has been variably performed. There is a paucity of evidence relating to its use. The limited data available show feasibility and potential clinical utility, and further investigation is warranted to establish whether lactate might give meaningful guidance during prehospital triage and trauma patient resuscitation.

LEVEL OF EVIDENCE

Systematic review, level IV.

Validation of a hand-held point of care device for lactate in adult and pediatric patients using traditional and locally-smoothed median and maximum absolute difference curves

BACKGROUND

Lactate is commonly used in septic patients and is a viable biomarker for trauma patients. Its pre-hospital use could assist triaging and managing patients with these conditions.

METHODS

We evaluated the analytical performance of the point-of-care (POC) StatStrip Xpress Lactate Meter (Nova Biomedical) and compared it to the ABL 800 (Radiometer). We measured lactate in 250 adult and 250 pediatric whole blood samples in 2 laboratories. The performance of the POC meter was assessed by traditional linear regression and Bland-Altman plots, and locally-smoothed (LS) median absolute difference and maximum absolute difference (MAD and MaxAD) curves.

RESULTS

The StatStrip was linear with acceptable reproducibility at clinically relevant concentrations. Correlation with the ABL800 showed a negative bias for both populations with slope, bias ±SD (% bias) of 0.78, -0.4±0.7 (-14.5%) in children and 0.80-0.3±0.6 (-13.3%) in adults. The proportional bias appeared more significant at concentrations >4mmol/l (36.0mg/dl). The StatStrip misclassified 7.6 and 8.8% pediatric and adult samples, respectively, to lower risk categories defined using guidelines driven cut-offs. The LS MAD curves identified one breakout, concentration where the LS MAD exceeds the total allowable error limit of 0.3mmol/l (2.7mg/dl), at lactate concentrations of 3.8 and 3.2mmol/l (34.2 and 28.8mg/dl) in the pediatric and adult curves, respectively. Breakthroughs, points at which the LS MaxAD curve exceeds the 95th percentile of MaxADs, occur at concentrations above 7.5mmol/l (67.6mg/dl) for both populations where the performance of the POC meter became erratic. We concluded that if serial lactate measurements are performed, the same method should be used for baseline and follow up measurements. The LS MAD and LS MaxAD curves allowed visual and quantitative mapping of the performance of the lactate POC meter over the range of concentrations measured.

CONCLUSIONS

This approach seems useful for the identification of points at which the performance of a POC meter differs significantly from a comparison method and thresholds of poor analytical performance.

Characteristics and Outcomes of Blood Product Transfusion During Critical Care Transport

BACKGROUND

Civilian out-of-hospital transfusions have not been adequately studied. This study seeks to characterize patients receiving out-of-hospital blood product transfusion during critical care transport.

STUDY DESIGN AND METHODS

We studied patients transported by a regional critical care air-medical service who received blood products during transport. This service carries two units of uncrossmatched packed Red Blood Cells (pRBCs) on every transport in addition to blood obtained from referring facilities. The pRBC are administered according to a protocol for the treatment of hemorrhagic shock or based on medical command physician order. Transfusion amount was categorized into three groups based on the volume transfused (<350 mL, 350-700 mL, >700 mL). The association between prehospital transfusion and in-hospital outcomes (mortality, subsequent blood transfusion and emergent surgery) was estimated using logistic regression models, controlling for age, first systolic blood pressure, first heart rate, Glasgow Coma Score, time of transfer, and length of hospital admission.

RESULTS

Among the 1,440 critical care transports with transfusions examined, 81% were for medical patients, being gastrointestinal hemorrhage the most common indication (26%, CI 24-28%). pRBC transfusions were associated with emergent surgery (OR = 1.81, 95% CI = 1.31-2.52) and in-hospital transfusions (OR = 2.00, 95% CI = 1.46-2.76). Those with transfusions >700 mL were associated with emergent surgery (OR = 1.79, 95% CI = 1.10-2.92) and mortality (OR = 2.11; 95% CI = 1.21-3.69).

CONCLUSIONS

In this sample, the majority of patients receiving blood products during air-medical transport were transfused for medic conditions; gastrointestinal hemorrhage was the most common chief complaint. The pRBC transfusions were associated with emergent surgery and in-hospital transfusion. Transfusions of >700 mL were associated with mortality.

Prehospital Lactate Measurement by Emergency Medical Services in Patients Meeting Sepsis Criteria

Introduction

We aimed to pilot test the delivery of sepsis education to emergency medical services (EMS) providers and the feasibility of equipping them with temporal artery thermometers (TATs) and handheld lactate meters to aid in the prehospital recognition of sepsis.

Methods

This study used a convenience sample of prehospital patients meeting established criteria for sepsis. Paramedics received education on systemic inflammatory response syndrome (SIRS) criteria, were trained in the use of TATs and hand-held lactate meters, and enrolled patients who had a recent history of infection, met ≥ 2 SIRS criteria, and were being transported to a participating hospital. Blood lactate was measured by paramedics in the prehospital setting and again in the emergency department (ED) via usual care. Paramedics entered data using an online database accessible at the point of care.

Results

Prehospital lactate values obtained by paramedics ranged from 0.8 to 9.8 mmol/L, and an elevated lactate (i.e. ≥ 4.0) was documented in 13 of 112 enrolled patients (12%). The unadjusted correlation of prehospital and ED lactate values was 0.57 (p< 0.001). The median interval between paramedic assessment of blood lactate and the electronic posting of the ED-measured lactate value in the hospital record was 111 minutes. Overall, 91 patients (81%) were hospitalized after ED evaluation, 27 (24%) were ultimately diagnosed with sepsis, and 3 (3%) died during hospitalization. Subjects with elevated prehospital lactate were somewhat more likely to have been admitted to the intensive care unit (23% vs 15%) and to have been diagnosed with sepsis (38% vs 22%) than those with normal lactate levels, but these differences were not statistically significant.

Conclusion

In this pilot, EMS use of a combination of objective SIRS criteria, subjective assessment of infection, and blood lactate measurements did not achieve a level of diagnostic accuracy for sepsis that would warrant hospital prenotification and committed resources at a receiving hospital based on EMS assessment alone. Nevertheless, this work provides an early model for increasing EMS awareness and the implementation of novel devices that may enhance the prehospital assessment for sepsis. Additional translational research studies with larger numbers of patients and more robust methods are needed.

Is lactate an effective clinical marker of outcome for children with major trauma? - A literature review

INTRODUCTION

The assessment and treatment of children with major injury is fraught with difficulty - differences in anatomy and physiology mean that children that have suffered trauma can be over or under assessed. In recent years, there has been an increase in the use of biochemical markers, such as haematocrit, to assist the clinician in determining severity of injury. This paper examines the evidence surrounding lactate as a marker in paediatric trauma.

METHOD

A literature search was completed on Medline, CINAHL, Ovid and Science. 63 papers were initially identified - 41 papers were rejected after reading the abstracts. Of the 22 remaining papers - 6 had a paediatric focus, 16 were adult - of these 12 were rejected as not primary studies. Ten papers were fully critically reviewed - of these only one article related to paediatric patients and trauma.

RESULTS

The literature shows that an elevated lactate in a trauma patient is strongly correlated to severity of injury, length of stay and morbidity and mortality. However, one elevated lactate may be misleading and lactate clearance - that is the time when lactate levels return to normal, is just as important in the assessment of the severely injured. However, from this literature review it is clear that there is very little evidence for the relationship between lactate levels and trauma in children and that more studies are required.

[Biomarkers in pediatric polytrauma]

BACKGROUND

Trauma represents one of the leading causes of death in children. Beside an injury pattern that differs from adult trauma patients, children seem to develop multiple organ dysfunction syndrome (MODS) less frequently. Compared to adult MODS, pediatric MODS has also been described to occur earlier in the posttraumatic course.

METHOD

Biomarkers for early identification of patients at high-risk for posttraumatic complications are of high clinical relevance. However, little is known from clinical studies about the relevance of biomarkers during the posttraumatic course.

AIM

Therefore, the purpose of this review is to summarize current knowledge on this topic in order to investigate the prognostic significance of different parameters.

A comparison of prehospital lactate and systolic blood pressure for predicting the need for resuscitative care in trauma transported by ground

BACKGROUND

Reliance on prehospital trauma triage guidelines misses patients with serious injury. Lactate is a biomarker capable of identifying high-risk trauma patients. Our objective was to compare prehospital point-of-care lactate (P-LAC) with systolic blood pressure (SBP) for predicting the need for resuscitative care (RC) in trauma patients transported by ground emergency medical services.

METHODS

This is a prospective observational study at nine sites within the Resuscitation Outcomes Consortium conducted from March 2011 to August 2012. Lactate was measured on patients with a prehospital SBP of 100 mm Hg or less who were transported by emergency medical services to a Level I or II trauma center. Patients were followed up for the need for RC, defined as any of the following within 6 hours of emergency department arrival: blood transfusion of 5 U or greater; intervention for hemorrhage including thoracotomy, laparotomy, pelvic fixation, or interventional radiology embolization; or death.

RESULTS

A total of 387 patients had a lactate value and presented with SBP between 71 mm Hg and 100 mm Hg, and 70 (18%) required RC. With the use of a P-LAC decision rule (≥2.5 mmol/L) that yielded the same specificity as that of SBP of 90 mm Hg or less (48%), the observed sensitivities for RC were 93% (95% confidence interval [CI], 84-98%) for P-LAC of 2.5 mmol/L or greater and 67% (95% CI, 55-78%) for SBP of 90 mm Hg or less (McNemar's test, p < 0.001). P-LAC has an estimated area under the curve of 0.78 (95% CI, 0.73-0.83), which is statistically superior to that of SBP (0.59; 95% CI, 0.53-0.66) and shock index (heart rate / SBP) (0.66; 95% CI, 0.60-0.74).

CONCLUSION

P-LAC obtained at the scene is associated with the need for RC. P-LAC is superior to other early surrogates for hypoperfusion (SBP and shock index) in predicting the need for RC in trauma patients with 70 mm Hg < SBP ≤ 100 mm Hg.

LEVEL OF EVIDENCE

Prognostic study, level II.

Pediatric specific shock index accurately identifies severely injured children

INTRODUCTION

Shock index (SI) (heart rate/systolic blood pressure)>0.9 predicts mortality in adult trauma patients. We hypothesized that age adjusted SI could more accurately predict outcomes in children.

METHODS

Retrospective review of children age 4-16 years admitted to two trauma centers between 1/07 and 6/13 following blunt trauma with an injury severity score (ISS)>15 was performed. We evaluated the ability of SI>0.9 at emergency department presentation and elevated shock index, pediatric age adjusted (SIPA) to predict outcomes. SIPA was defined by maximum normal HR and minimum normal SBP by age. Cutoffs included SI>1.22 (age 4-6), >1.0 (7-12), and >0.9 (13-16).

RESULTS

Among 543 children, 50% of children had an SI>0.9 but this fell to 28% using age adjusted SI (SIPA). SIPA demonstrated improved discrimination of severe injury relative to SI: ISS>30: 37% vs 26%; blood transfusion within the first 24 hours: 27% vs 20%; Grade III liver/spleen laceration requiring blood transfusion: 41% vs 26%; and in-hospital mortality: 11% vs 7%.

CONCLUSION

A pediatric specific shock index (SIPA) more accurately identifies children who are most severely injured, have intraabdominal injury requiring transfusion, and are at highest risk of death when compared to shock index unadjusted for age.

[Point-of-care testing in preclinical emergency medicine]

BACKGROUND

Measurement of biological signals directly at the patient (point-of-care testing, POCT) is an established standard in emergency medicine when test results are needed quickly and within a reliable time frame or if external testing requires a disproportionate effort.

OBJECTIVES

Currently, the rapid test for β-HCG in urine and POCT measurement of lactate, blood gases, cardiac tropinin, haemoglobin, and hematocrit are well established in emergency medicine. POCT of copeptin, fatty acid-binding proteins (FABP), procalcitonin, coagulation values, natriuretic peptides, D-dimer, and toxicological substances are of future interest. In this article, the appropriate use of point-of-care testing in prehospital emergency medicine is discussed.

RESULTS

Application of POCT is dependent of the underlying conditions, the availability of appropriate devices, and of suitable reference methods in a central laboratory. In addition, economical and quality aspects play an important role.

CONCLUSION

In emergency departments, POCT is currently developing into a standard measuring method for a number of markers because hospital laboratories are increasingly being merged and consequently reduce their emergency-analytic services. In countries with a high density of hospitals, however, preclinical POCT should be reduced to the minimum necessary.

Pre-resuscitation lactate and hospital mortality in prehospital patients

OBJECTIVE

Serum lactate elevations are associated with morbidity and mortality in trauma patients, but their value in prehospital medical patients prior to resuscitation is unknown. We sought to assess the distribution of blood lactate concentrations prior to intravenous (i.v.) resuscitation and examine the association of elevation on in-hospital death.

METHODS

A convenience sample of adult patients over 14 months who received an i.v. line by eight EMS agencies in Western Pennsylvania had lactate measurement prior to any i.v. treatment. We assessed the lactate values and any relationship between these and hospital mortality (our primary outcome) and admission to the intensive care unit (ICU). We also compared the ability of lactate to discriminate outcomes with a prehospital critical illness score using age, Glasgow Coma Score, and initial vital signs.

RESULTS

We included 673 patients, among whom 71 (11%) were admitted to the ICU and 21 (3.1%) died in-hospital. Elevated lactate (≥2 mmol/L) occurred in 307 (46%) patients and was strongly associated with hospital death after adjustment for known covariates (odds ratio = 3.57, 95% confidence interval [CI]: 1.10, 11.6). Lactate ≥2 mmol/L had a modest sensitivity (76%) and specificity (55%), and discrimination for hospital death (area under the curve [AUC] = 0.66, 95%CI: 0.56, 0.75). Compared to the prehospital critical illness score alone (AUC = 0.69, 95% CI: 0.59, 0.80), adding lactate to the score offered modest improvement (net reclassification improvement = 0.63, 95%CI: 0.23, 1.01, p < 0.05).

CONCLUSIONS

Initial lactate concentration in our prehospital medical patient population was associated with hospital mortality. However, it is a modest predictor of outcome, offering similar discrimination to a prehospital critical illness score.