Influence of definition and location of hypotension on outcome following severe pediatric traumatic brain injury*

[Intraoperative hypotension in children-Measurement and treatment]

Intraoperative hypotension is a common perioperative complication in pediatric anesthesia. Oscillometric blood pressure measurement is therefore an essential part of standard perioperative monitoring in pediatric anesthesia. The optimum measurement site is the upper arm. Attention must be paid to the correct cuff size. Blood pressure should be measured before induction. In children undergoing major surgery or in critically ill children, invasive blood pressure measurement is still the gold standard. Continuous noninvasive measurement methods could be an alternative in the future.Threshold values to define hypotension remain unknown, even in awake children. There are also little data on hypotension thresholds in the perioperative setting. The most reliable measurement parameter for estimating hypotension is the mean arterial pressure. The threshold values for intraoperative hypotension are 40 mm Hg in newborns, 45 mm Hg in infants, 50 mm Hg in young children and 65 mm Hg in adolescents. Treatment should be initiated at a deviation of 10% and intensified at a deviation of 20%.Bolus administration of isotonic balanced crystalloid solutions, vasopressors and/or catecholamines are used as treatment options. Consistent and rapid intervention in the event of hypotension appears to be crucial. So far there is no evidence as to whether this leads to an improvement in outcome parameters.

Neuroprotection or Sex Bias: A Protective Response to Traumatic Brain Injury in the Females

Traumatic brain injury (TBI) is a major healthcare problem and a common cause of mortality and morbidity. Clinical and preclinical research suggests sex-related differences in short- and longterm outcomes following TBI; however, males have been the main focus of TBI research. Females show a protective response against TBI. Female animals in preclinical studies and women in clinical trials have shown comparatively better outcomes against mild, moderate, or severe TBI. This reflects a favorable protective nature of the females compared to the males, primarily attributed to various protective mechanisms that provide better prognosis and recovery in the females after TBI. Understanding the sex difference in the TBI pathophysiology and the underlying mechanisms remains an elusive goal. In this review, we provide insights into various mechanisms related to the anatomical, physiological, hormonal, enzymatic, inflammatory, oxidative, genetic, or mitochondrial basis that support the protective nature of females compared to males. Furthermore, we sought to outline the evidence of multiple biomarkers that are highly potential in the investigation of TBI's prognosis, pathophysiology, and treatment and which can serve as objective measures and novel targets for individualized therapeutic interventions in TBI treatment. Implementations from this review are important for the understanding of the effect of sex on TBI outcomes and possible mechanisms behind the favorable response in females. It also emphasizes the critical need to include females as a biological variable and in sufficient numbers in future TBI studies.

Predictors of neurologic outcomes and mortality in physically abused and unintentionally injured children: a retrospective observation study

OBJECTIVES

This study aimed to identify the predictors of neurologic outcomes and mortality in physically abused and unintentionally injured children admitted to intensive care units (ICUs).

METHODS

All maltreated children were admitted to pediatric, neurosurgical, and trauma ICUs between 2001 and 2019. Clinical factors, including age, sex, season of admission, identifying settings, injury severity score, etiologies, length of stay in the ICU, neurologic outcomes, and mortality, were analyzed and compared between the physically abused and unintentionally injured groups. Neurologic assessments were conducted using the Pediatric Cerebral Performance Category scale. The study was approved by the Institutional Review Board of Chang Gung Memorial Hospital and the Ethics Committee waived the requirement for informed consent because of the anonymized nature of the data.

RESULTS

A total of 2481 children were investigated; of them, there were 480 (19.3%) victims admitted to the ICUs, including 156 physically abused and 324 unintentionally injured. Age, history of prematurity, clinical outcomes, head injury, neurosurgical interventions, clinical manifestations, brain computed tomography findings, and laboratory findings significantly differed between them (all p < 0.05). Traumatic brain injury was the major etiology for admission to the ICU. The incidence of abusive head trauma was 87.1% among the physically abused group. Only 46 (29.4%) and 268 (82.7%) cases achieved favorable neurologic outcomes in the physically abused and unintentionally injured groups, respectively. Shock within 24 h, spontaneous hypothermia (body temperature, < 35 °C), and post-traumatic seizure were strongly associated with poor neurologic outcomes and mortality in both groups.

CONCLUSIONS

Initial presentation with shock, spontaneous hypothermia at ICU admission, and post-traumatic seizure were associated with poor neurologic outcomes and mortality in physically abused and unintentionally injured children.

Cardiovascular events in children with brain injury: A systematic review

BACKGROUND

Brain injury is a leading cause of morbidity and mortality in the pediatric population. Neurogenic stunned cardiomyopathy is a complication associated with several neurological conditions that can lead to worse outcomes. It presents as alterations in blood pressure, cardiac rhythm disturbances and the increase in cardiac injury biomarkers. This systematic review aims to assess the hemodynamic consequences of brain injury in the pediatric population to identify better management strategies and improve outcomes.

METHODS

An electronic literature search was performed in Pubmed, Scopus and WebOfScience, up until October 3rd, 2022. The selected articles underwent quality assessment using the National Heart, Lung and Blood Institute tools for cohort and case-control studies.

RESULTS

This systematic review includes thirteen articles on the effects of brain injury in arterial pressure, rhythm disturbances and biomarkers of myocardial injury. These studies showed the following key results: both hypotension and hypertension are associated with worse outcomes; brain injury could be related to longer QTc intervals; neurogenic stunned cardiomyopathy was a common found after brain injury.

CONCLUSION

This is the first systematic review to report cardiovascular abnormalities arising from brain injury in children. An early arterial pressure, electrocardiographic and echocardiographic evaluation, as well as the measure of serum biomarkers for myocardial injury, can be critical in identifying poor prognostic factors. Further research is required to understand the implications of our findings in clinical practice.

Prognostic Factors and Outcome of Surgically Treated Supratentorial versus Infratentorial Epidural Hematoma in Pediatrics: A Comparative Study of 350 Patients at a Tertiary Center of a Developing Country

PURPOSE

In children, epidural hematomas (EDHs) constitute around 2% to 3% of all head traumas. The aim of this study is to compare the manifestation, prognostic factors, and outcome of surgically treated supratentorial with infratentorial EDHs in pediatric patients.

METHODS

This is a hospital-based single-center, retrospective study of 350 pediatric patients admitted between January 2016 and December 2021. All pediatric patients to 18 years of age with posttraumatic EDHs with or without other intracranial/extracranial injuries who underwent surgical evacuation were included in the study. Posttraumatic EDHs treated conservatively during the hospital stay and any EDH unrelated to head trauma were excluded. Glasgow Outcome Scale (GOS) score was used to assess functional outcomes at discharge. The status of the patients at 3-month follow-up was assessed by using the pediatric version of the Glasgow Outcome Scale-Extended (GOS-E Peds) Score.

RESULTS

Out of 350 patients, 310 had supratentorial EDH and 40 had infratentorial EDH. In supratentorial EDH, the volume of hematoma, mass effect, and the time interval between trauma and surgery correlated with functional outcome (GOS) at discharge. Anisocoria, hypotension, and intradural injury were associated with functional as well as behavioral outcomes (GOS-E Peds) in the supratentorial EDH group. The severity of the injury was correlated with the functional and behavioral outcomes in both groups.

CONCLUSIONS

Infratentorial EDH has better clinical outcomes than supratentorial EDH in surgically treated pediatric patients. The most significant and consistent factor influencing the outcome in both groups was the Glasgow Coma Score on admission.

Single bolus dexmedetomidine versus propofol for treatment of pediatric emergence delirium following general anesthesia

BACKGROUND

Pediatric emergence delirium is a psychomotor disorder occurring in the early postanesthetic stage. There is no clear consensus regarding its treatment; however, dexmedetomidine and propofol have both been shown to be effective.

AIM

In this single-center, randomized, double-blind prospective study, we compared the efficacy of dexmedetomidine against that of propofol in the treatment of established emergence delirium in pediatric patients undergoing general anesthesia.

METHODS

Patients aged 1-14 years, with ASA I or II and severe emergence delirium (Pediatric Anesthesia Emergence Delirium score of ≥15) during the postoperative period following general anesthesia, were randomized to receive intravenous bolus injection of 0.5 μg.kg^-1 dexmedetomidine or 1 mg.kg^-1 propofol. The primary outcome was the pediatric anesthesia emergence delirium (PAED) score after treatment, and the secondary outcome was the recovery time in the postanesthetic care unit.

RESULTS

Of the 53 patients who participated in the study, 26 (49%) were treated with dexmedetomidine and 27 (51%) with propofol. In the dexmedetomidine group, a single-dose intervention was effective for all patients (100%); whereas in the propofol group, 19 patients (70.4%) had PAED score of <12 after the first dose (p = .004; relative risk [95% confidence interval] = 0.1422 [0.113-1.815]). No significant difference in recovery time (median [IQR (range)]) was observed between the dexmedetomidine (20[14-30(10-45)]) and propofol groups (25 [20-40 (10-50)]; p = .056; 95% confidence interval = 0.113-1.815).

CONCLUSIONS

A single bolus of 0.5 μg.kg^-1 of dexmedetomidine was more effective than a single bolus of 1 mg.kg^-1 of propofol in treating emergence delirium during the early postanesthetic stage.

An unambiguous definition of pediatric hypotension is still lacking: Gaps between two percentile-based definitions and Pediatric Advanced Life Support/Advanced Trauma Life Support guidelines

BACKGROUND

Data are lacking to provide cutoffs for hypotension in children based on outcome studies and Pediatric Advanced Life Support (PALS), and Advanced Trauma Life Support (ATLS) definitions are based on normal populations. The goal of this study was to compare different normal population based cutoffs including fifth percentile of systolic blood pressure (P5-SBP) in children and adolescents from the German Health Examination Survey for Children and Adolescents (KiGGS), US population data (Fourth Report), and cutoffs from PALS and ATLS guidelines.

METHODS

Fifth percentile of systolic blood pressure according to age, sex, and height was modeled based on standardized resting oscillometric BP measurements (12,199 children aged 3-17 years) from KiGGS 2003-2006. In addition, we applied the age-adjusted pediatric shock index in the KiGGS study.

RESULTS

The KiGGS P5-SBP was on average 7 mm Hg higher than Fourth Report P5-SBP (5-10 mm Hg depending on age-sex group). For children aged 3 to 9 years, KIGGS P5-SBP at median height follows the formula 82 mm Hg + age; for age 10 to 17 years, the increase was not linear and is presented in a simplified table. Pediatric Advanced Life Support/ATLS thresholds were between KiGGS and Fourth Report until age of 11 years. The adult threshold of 90 mm Hg was reached by KiGGS P5-SBP median height at 8 years, PALS/ATLS at age of 10 years, and Fourth Report P5-SBP at 12 years. The pediatric shock index, which is supposed to identify severely injured children, was exceeded by 2.3% nonacutely ill KiGGS participants.

CONCLUSION

Our study shows that percentile cutoffs vary by reference population. The 90 mm Hg cutoff for adolescents targets only those in the less than 1% of the low SBP range and represents an undertriage compared with P5 at younger ages according to both KiGGS and Fourth Report. Finally, current pediatric shock index cutoffs when applied to a healthy cohort lead to a relevant percentage of false positives.

LEVEL OF EVIDENCE

Epidemiologic/prognostic, level III.

Injury Causes and Severity in Pediatric Traumatic Brain Injury Patients Admitted to the Ward or Intensive Care Unit: A Collaborative European Neurotrauma Effectiveness Research in Traumatic Brain Injury (CENTER-TBI) Study

Background: Traumatic brain injury (TBI) is the leading cause of death and disability in children. It includes a range of different pathologies that differ considerably from adult TBI. Analyzing and understanding injury patterns of pediatric TBI is essential to establishing new preventive efforts as well as to improve clinical management.

Methods: The multi-center, prospectively collected CENTER-TBI core and registry databases were screened and patients were included when younger than 18 years at enrollment and admitted to the regular ward (admission stratum) or intensive care unit (ICU stratum) following TBI. Patient demographics, injury causes, clinical findings, brain CT imaging details, and outcome (GOSE at 6 months follow-up) were retrieved and analyzed. Injury characteristics were compared between patients admitted to the regular ward and ICU and multivariate analysis of factors predicting an unfavorable outcome (GOSE 1-4) was performed. Results from the core study were compared to the registry dataset which includes larger patient numbers but no follow-up data.

Results: Two hundred and twenty seven patients in the core dataset and 687 patients in the registry dataset were included in this study. In the core dataset, road-traffic incidents were the most common cause of injury overall and in the ICU stratum, while incidental falls were most common in the admission stratum. Brain injury was considered serious to severe in the majority of patients and concurrent injuries in other body parts were very common. Intracranial abnormalities were detected in 60% of initial brain CTs. Intra- and extracranial surgical interventions were performed in one-fifth of patients. The overall mortality rate was 3% and the rate of unfavorable outcome 10%, with those numbers being considerably higher among ICU patients. GCS and the occurrence of secondary insults could be identified as independent predictors for an unfavorable outcome. Injury characteristics from the core study could be confirmed in the registry dataset.

Conclusion: Our study displays the most common injury causes and characteristics of pediatric TBI patients that are treated in the regular ward or ICU in Europe. Road-traffic incidents were especially common in ICU patients, indicating that preventive efforts could be effective in decreasing the incidence of severe TBI in children.

Does hypertension at initial presentation adversely affect outcomes in pediatric traumatic brain injury?

BACKGROUND

Adults with traumatic brain injury (TBI) who present hypertensive suffer worse outcomes and increased mortality compared to normotensive patients. The purpose of this study is to determine if age-adjusted hypertension on presentation is associated with worsened outcomes in pediatric TBI.

METHODS

A retrospective chart review was conducted on pediatric patients with severe TBI admitted to a single system pediatric tertiary care center. The primary outcome was mortality. Secondary outcomes included length of stay, need for neurosurgical intervention, duration of mechanical ventilation, and the need for inpatient rehabilitation.

RESULTS

Of 150 patients, 70% were hypertensive and 30% were normotensive on presentation. Comparing both groups, no statistically significant differences were noted in mortality (13.3% for both groups), need for neurosurgical intervention (51.4% vs 48.8%, p = 0.776), length of stay (6 vs 8 days, p = 0.732), duration of mechanical ventilation (2 vs 3 days, p = 0.912), or inpatient rehabilitation rates (48.6% vs 48.9%, p = 0.972). In comparing just the hypertensive patients, there was a trend toward increased mortality in the 95th and 99th percentile groups at 15.8% and 14.1%, versus the 90th percentile group at 6.7% but the difference was not statistically significant (p = 0.701).

CONCLUSIONS

Contrary to the adult literature, pediatric patients with severe TBI and hypertension on presentation do not appear to have worsened outcomes compared to those who are normotensive. However, a trend toward increased mortality did exist at extremes of age adjusted hypertension. Larger scale studies are needed to validate these findings.

STUDY TYPE

Retrospective cohort study LEVEL OF EVIDENCE: III.

The Base Deficit, International Normalized Ratio, and Glasgow Coma Scale (BIG) Score, and Functional Outcome at Hospital Discharge in Children With Traumatic Brain Injury

OBJECTIVES

To examine the association of the base deficit, international normalized ratio, and Glasgow Coma Scale (BIG) score on emergency department arrival with functional dependence at hospital discharge (Pediatric Cerebral Performance Category ≥ 4) in pediatric multiple trauma patients with traumatic brain injury.

DESIGN

A retrospective cohort study of a pediatric trauma database from 2001 to 2018.

SETTING

Level 1 trauma program at a university-affiliated pediatric institution.

PATIENTS

Two to 17 years old children sustaining major blunt trauma including a traumatic brain injury and meeting trauma team activation criteria.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Two investigators, blinded to the BIG score, determined discharge Pediatric Cerebral Performance Category scores. The BIG score was measured on emergency department arrival. The 609 study patients were 9.7 ± 4.4 years old with a median Injury Severity Score 22 (interquartile range, 12). One-hundred seventy-one of 609 (28%) had Pediatric Cerebral Performance Category greater than or equal to 4 (primary outcome). The BIG constituted a multivariable predictor of Pediatric Cerebral Performance Category greater than or equal to 4 (odds ratio, 2.39; 95% CI, 1.81-3.15) after adjustment for neurosurgery requirement (odds ratio, 2.83; 95% CI, 1.69-4.74), pupils fixed and dilated (odds ratio, 3.1; 95% CI, 1.49-6.38), and intubation at the scene or referral hospital (odds ratio, 2.82; 95% CI, 1.35-5.87) and other postulated predictors of poor outcome. The area under the BIG receiver operating characteristic curve was 0.87 (0.84-0.90). Using an optimal BIG cutoff less than or equal to 8, sensitivity and negative predictive value for functional dependence at discharge were 93% and 96%, respectively, compared with a sensitivity of 79% and negative predictive value of 91% with Glasgow Coma Scale less than or equal to 8. In children with Glasgow Coma Scale 3, the BIG score was associated with brain death (odds ratio, 2.13; 95% CI, 1.58-2.36). The BIG also predicted disposition to inpatient rehabilitation (odds ratio, 2.26; 95% CI, 2.17-2.35).

CONCLUSIONS

The BIG score is a simple, rapidly obtainable severity of illness score that constitutes an independent predictor of functional dependence at hospital discharge in pediatric trauma patients with traumatic brain injury. The BIG score may benefit Trauma and Neurocritical care programs in identifying ideal candidates for traumatic brain injury trials within the therapeutic window of treatment.

A systematic review of large animal models of combined traumatic brain injury and hemorrhagic shock

Traumatic brain injury (TBI) and severe blood loss (SBL) frequently co-occur in human trauma, resulting in high levels of mortality and morbidity. Importantly, each of the individual post-injury cascades is characterized by complex and potentially opposing pathophysiological responses, complicating optimal resuscitation and therapeutic approaches. Large animal models of poly-neurotrauma closely mimic human physiology, but a systematic literature review of published models has been lacking. The current review suggests a relative paucity of large animal poly-neurotrauma studies (N = 52), with meta-statistics revealing trends for animal species (exclusively swine), characteristics (use of single biological sex, use of juveniles) and TBI models. Although most studies have targeted blood loss volumes of 35-45%, the associated mortality rates are much lower relative to Class III/IV human trauma. This discrepancy may result from potentially mitigating experimental factors (e.g., mechanical ventilation prior to or during injury, pausing/resuming blood loss based on physiological parameters, administration of small volume fluid resuscitation) that are rarely associated with human trauma, highlighting the need for additional work in this area.

Sex Differences in Animal Models of Traumatic Brain Injury

Traumatic brain injury (TBI) is highly prevalent and there is currently no adequate treatment. Understanding the underlying mechanisms governing TBI and recovery remains an elusive goal. The heterogeneous nature of injury and individual's response to injury have made understanding risk and susceptibility to TBI of great importance. Epidemiologic studies have provided evidence of sex-dependent differences following TBI. However, preclinical models of injury have largely focused on adult male animals. Here, we review 50 studies that have investigated TBI in both sexes using animal models. Results from these studies are highly variable and model dependent, but largely show females to have a protective advantage in behavioral outcomes and pathology following TBI. Further research of both sexes using newer models that better recapitulate mild and repetitive TBI is needed to characterize the nature of sex-dependent injury and recovery, and ultimately identifies targets for enhanced recovery.

Risk factors for post-induction hypotension in children presenting for surgery

BACKGROUND

Preoperative factors have been correlated with pre-incision hypotension (PIH) in children undergoing surgery, suggesting that PIH can be predicted through preoperative screening. We studied blood pressure (BP) changes in the 12 min following the induction of anesthesia to study the incidence of post-induction hypotension and to assess the feasibility of predicting PIH in low-risk children without preoperative hypotension or comorbid features.

METHODS

We retrospectively evaluated 200 patients ranging in age from 2 to 8 years with American Society of Anesthesiologists' (ASA) physical status I or II, undergoing non-cardiac surgery. Patients were excluded if they had preoperative (baseline) hypotension (systolic blood pressure (SBP) < 5th percentile for age). BP and heart rate (HR) were recorded at 3 min intervals for 12 min after the induction of anesthesia. Pre-incision hypotension (PIH) was initially defined as SBP < 5th percentile for age: (1) at any timepoint within 12 min of induction; (2) for the median SBP obtained during the 12 min study period; or (3) at 2 or more timepoints including the final point at 12 min after the induction of anesthesia (sustained hypotension). In addition, we examined PIH defined as > 20% decrease in SBP from baseline: (4) at any timepoint within 12 min of the induction of anesthesia; (5) for the median SBP obtained during the 12 min study period; or (6) at two or more timepoints including the final point at 12 min after the induction of anesthesia. Agreement among the six definitions was analyzed, in addition to the effects of age, gender, type of anesthetic induction, use of premedication, preoperative BP, preoperative HR, and body mass index on the incidence of PIH according to each definition.

RESULTS

Five patients were excluded due to baseline hypotension and six were excluded for missing data. In the remaining cohort, estimated PIH prevalence ranged from 4% [definition (Stewart et al., in Paediatr Anaesth 26:844-851, 2016), sustained PIH according to SBP percentile-for-age] to 57% [definition (Task Force on Blood Pressure Control in Children, in Pediatrics 79:1-25, 1987), at least one timepoint where SBP was > 20% lower than baseline]. Pairwise agreement among the six definitions ranged from 49 to 91% agreement. No sequelae of PIH were noted during subsequent anesthetic or postoperative care. On multivariable analysis, no covariates were consistently associated with PIH risk across all six definitions of PIH.

CONCLUSION

The present study describes the incidence and prediction of PIH in a cohort of relatively healthy children. In this setting, accurate prediction of PIH appears to be hampered by lack of agreement between definitions of PIH. Overall, there was a low PIH incidence when the threshold of SBP < 5th percentile for age was used.

LEVEL OF EVIDENCE

II.

Timely Hemodynamic Resuscitation and Outcomes in Severe Pediatric Traumatic Brain Injury: Preliminary Findings

OBJECTIVES

Early resuscitation may improve outcomes in pediatric traumatic brain injury (TBI). We examined the association between timely treatment of hypotension and hypoxia during early care (prehospital or emergency department locations) and discharge outcomes in children with severe TBI.

METHODS

Hypotension was defined as systolic blood pressure less than 70 + 2 (age in years), and hypoxia was defined as PaO2 less than 60 mm Hg or oxygen saturation less than 90% in accordance with the 2003 Brain Trauma Foundation guidelines. Timely treatment of hypotension and hypoxia during early care was defined as the treatment within 30 minutes of a documented respective episode. Two hundred thirty-six medical records of children younger than 18 years with severe TBI from 5 regional pediatric trauma centers were examined. Main outcomes were in-hospital mortality and discharge Glasgow Outcome Scale (GOS) score.

RESULTS

Hypotension occurred in 26% (60/234) during early care and was associated with in-hospital mortality (23.3% vs 8.6%; P = 0.01). Timely treatment of hypotension during early care occurred in 92% (55/60) by use of intravenous fluids, blood products, or vasopressors and was associated with reduced in-hospital mortality [adjusted relative risk (aRR), 0.46; 95% confidence interval, 0.24-0.90] and less likelihood of poor discharge GOS (aRR, 0.54; 95% confidence interval, 0.39-0.76) when compared to children with hypotension who were not treated in a timely manner. Early hypoxia occurred in 17% (41/236) and all patients received timely oxygen treatment.

CONCLUSIONS

Timely resuscitation during early care was common and associated with lower in-hospital mortality and favorable discharge GOS in severe pediatric TBI.

Systematic review and need assessment of pediatric trauma outcome benchmarking tools for low-resource settings

INTRODUCTION

Trauma is a leading cause of mortality and disability in children worldwide. The World Health Organization reports that 95% of all childhood injury deaths occur in Low-Middle-Income Countries (LMIC). Injury scores have been developed to facilitate risk stratification, clinical decision making, and research. Trauma registries in LMIC depend on adapted trauma scores that do not rely on investigations that require unavailable material or human resources. We sought to review and assess the existing trauma scores used in pediatric patients. Our objective is to determine their wideness of use, validity, setting of use, outcome measures, and criticisms. We believe that there is a need for an adapted trauma score developed specifically for pediatric patients in low-resource settings.

MATERIALS AND METHODS

A systematic review of the literature was conducted to identify and compare existing injury scores used in pediatric patients. We constructed a search strategy in collaboration with a senior hospital librarian. Multiple databases were searched, including Embase, Medline, and the Cochrane Central Register of Controlled Trials. Articles were selected based on predefined inclusion criteria by two reviewers and underwent qualitative analysis.

RESULTS

The scores identified are suboptimal for use in pediatric patients in low-resource settings due to various factors, including reliance on precise anatomic diagnosis, physiologic parameters maladapted to pediatric patients, or laboratory data with inconsistent accessibility in LMIC.

CONCLUSION

An important gap exists in our ability to simply and reliably estimate injury severity in pediatric patients and predict their associated probability of outcomes in settings, where resources are limited. An ideal score should be easy to calculate using point-of-care data that are readily available in LMIC, and can be easily adapted to the specific physiologic variations of different age groups.

Defining Significant Events for Neonatal and Pediatric Transport: Results of a Combined Delphi and Consensus Meeting Process

Objective  To develop standardized definitions for a list of indicators that represent significant events during pediatric transport, which were previously identified by a national Delphi study. Methods  We designed a three-phase consensus process that applied Delphi methodology to a combination of electronic questionnaires and a live consensus meeting. Results  Thirty-one pediatric transport experts evaluated a total of 59 indicators. Twenty-four indicators represented events or interventions that did not require definition. One indicator was removed from the list. Definitions for the remaining 34 indicators were developed. Conclusion  This standardized indicator list is intended for application to quality improvement and clinical research initiatives.

Association of elevated preoperative blood pressure with preincision hypotension in pediatric surgical patients

INTRODUCTION

High blood pressure (BP) in childhood is associated with left ventricular hypertrophy and abnormal vascular reactivity even in apparently healthy children. This study examined the prevalence of high BP in children undergoing elective noncardiac operations. We also determined the association of preoperative high BP with preincision hypotension (PIH).

METHODS

This was a retrospective cohort study that used clinical and anthropometric data on children aged 3-17 years who underwent elective, noncardiac operations from January 2006 to January 2014. Preoperative blood pressure (BP) was used to stratify children into three categories: normal BP (systolic and diastolic BP below the 90th percentile), prehypertension (systolic and/or diastolic BP ≥90th percentile but <95th percentile or if the BP exceeds 120/80 mmHg even if it is below the 90th percentile), and hypertension (systolic and/or diastolic BP ≥95th percentile). Multivariable logistic regression analysis was used to calculate adjusted odds ratios for PIH using age, gender, body mass index (BMI), and BP categories as covariates.

RESULTS

Among 35832 children, the overall prevalence of prehypertension, hypertension, and hypertension by adult standards were 16.4%, 6.8%, and 3.3%, respectively. Overweight and obese children had higher rates of elevated BP. Presence of elevated baseline BP, high BMI category, and presence of OSA diagnosis were independent predictors of multiple episodes of PIH in a logistic regression model.

CONCLUSION

In children, preoperative high BP is an independent predictor of PIH. Although the longtime consequences of high BP are well known, this report provides the first intraoperative evidence of adverse event associated with preoperative high BP in children. Mechanisms underlying this hypotensive response are unclear.

Microparticles Impair Hypotensive Cerebrovasodilation and Cause Hippocampal Neuronal Cell Injury after Traumatic Brain Injury

Endothelin-1 (ET-1), tissue plasminogen activator (tPA), and extracellular signal-regulated kinases-mitogen activated protein kinase (ERK-MAPK) are mediators of impaired cerebral hemodynamics after fluid percussion brain injury (FPI) in piglets. Microparticles (MPs) are released into the circulation from a variety of cells during stress, are pro-thrombotic and pro-inflammatory, and may be lysed with polyethylene glycol telomere B (PEG-TB). We hypothesized that MPs released after traumatic brain injury impair hypotensive cerebrovasodilation and that PEG-TB protects the vascular response via MP lysis, and we investigated the relationship between MPs, tPA, ET-1, and ERK-MAPK in that process. FPI was induced in piglets equipped with a closed cranial window. Animals received PEG-TB or saline (vehicle) 30-minutes post-injury. Serum and cerebrospinal fluid (CSF) were sampled and pial arteries were measured pre- and post-injury. MPs were quantified by flow cytometry. CSF samples were analyzed with enzyme-linked immunosorbent assay. MP levels, vasodilatory responses, and CSF signaling assays were similar in all animals prior to injury and treatment. After injury, MP levels were elevated in the serum of vehicle but not in PEG-TB-treated animals. Pial artery dilation in response to hypotension was impaired after injury but protected in PEG-TB-treated animals. After injury, CSF levels of tPA, ET-1, and ERK-MAPK were all elevated, but not in PEG-TB-treated animals. PEG-TB-treated animals also showed reduction in neuronal injury in CA1 and CA3 hippocampus, compared with control animals. These results show that serum MP levels are elevated after FPI and lead to impaired hypotensive cerebrovasodilation via over-expression of tPA, ET-1, and ERK-MAPK. Treatment with PEG-TB after injury reduces MP levels and protects hypotensive cerebrovasodilation and limits hippocampal neuronal cell injury.

Use of Rotterdam CT scores for mortality risk stratification in children with traumatic brain injury

OBJECTIVES

The Rotterdam CT score refined features of the Marshall score and was designed to categorize traumatic brain injury type and severity in adults. The objective of this study was to determine whether the Rotterdam CT score can be used for mortality risk stratification after pediatric traumatic brain injury.

DESIGN

In children with moderate to severe traumatic brain injury, a comparison of observed versus predicted mortality was calculated using published model probabilities of adult mortality. Development and validation of a new pediatric mortality model using randomly selected prediction and validation samples from our cohort.

SETTING

A single level 1 pediatric trauma center.

SUBJECTS

Six hundred thirty-two children with moderate or severe traumatic brain injury.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Sixteen percent of the patients (101 of 632) died prior to hospital discharge. The predicted mortality based on Rotterdam score for adults with moderate or severe traumatic brain injury discriminated pediatric observed mortality well (area under the curve = 0.85; 95% CI, 0.80-0.89) but had poor calibration, overestimating or underestimating mortality for children in several Rotterdam categories. A predictive model based on children with moderate or severe traumatic brain injury from the single center discriminated mortality well (area under the curve, 0.80; 95% CI, 0.68-0.91) and showed good calibration and overall fit.

CONCLUSIONS

Children with traumatic brain injury have better survival than adults in Rotterdam CT score categories representing less severe injuries but worse survival than adults in higher score categories. A novel, validated pediatric mortality model based on the Rotterdam score is accurate in children with moderate or severe traumatic brain injury and can be used for risk stratification.

Intraoperative secondary insults during extracranial surgery in children with traumatic brain injury

PURPOSE

Data on intraoperative secondary insults in pediatric traumatic brain injury (TBI) are limited.

METHODS

We examined intraoperative secondary insults during extracranial surgery in children with moderate-severe TBI and polytrauma and their association with postoperative head computed tomography (CT) scans, intracranial pressure (ICP), and therapeutic intensity level (TIL) scores 24 h after surgery. After IRB approval, we reviewed the records of children <18 years with a Glasgow Coma Scale score <13 who underwent extracranial surgery within 72 h of TBI. Definitions of secondary insults were as follows: systemic hypotension (SBP <70 + 2 × age or 90 mmHg), cerebral hypotension (cerebral perfusion pressure <40 mmHg), intracranial hypertension (ICP >20 mmHg), hypoxia (oxygen saturation <90 %), hypercarbia (end-tidal CO2 >45 mmHg), hypocarbia (end-tidal CO2 <30 mmHg without hypotension and in the absence of intracranial hypertension), hyperglycemia (blood glucose >200 mg/dL), hyperthermia (temperature >38 °C), and hypothermia (temperature <35 °C).

RESULTS

Data from 50 surgeries in 42 patients (median age 15.5 years, 25 males) revealed systemic hypotension during 78 %, hypocarbia during 46 %, and hypercarbia during 25 % surgeries. Intracranial hypertension occurred in 64 % and cerebral hypotension in 18 % surgeries with ICP monitoring (11/50). Hyperglycemia occurred during 17 % of the 29 surgeries with glucose monitoring. Cerebral hypotension and hypoxia were associated with postoperative intracranial hypertension (p = 0.02 and 0.03, respectively). We did not observe an association between intraoperative secondary insults and postoperative worsening of head CT scan or TIL score.

CONCLUSIONS

Intraoperative secondary insults were common during extracranial surgery in pediatric TBI. Intraoperative cerebral hypotension and hypoxia were associated with postoperative intracranial hypertension. Strategies to prevent secondary insults during extracranial surgery in TBI are needed.

tPA-S(481)A prevents impairment of cerebrovascular autoregulation by endogenous tPA after traumatic brain injury by upregulating p38 MAPK and inhibiting ET-1

Traumatic brain injury (TBI) is associated with loss of cerebrovascular autoregulation, which leads to cerebral hypoperfusion. Mitogen activated protein kinase (MAPK) isoforms ERK, p38, and JNK and endothelin-1 (ET-1) are mediators of impaired cerebral hemodynamics after TBI. Excessive tissue plasminogen activator (tPA) released after TBI may cause loss of cerebrovascular autoregulation either by over-activating N-methyl-D-aspartate receptors (NMDA-Rs) or by predisposing to intracranial hemorrhage. Our recent work shows that a catalytically inactive tPA variant (tPA-S(481)A) that competes with endogenous wild type (wt) tPA for binding to NMDA-R through its receptor docking site but that cannot activate it, prevents activation of ERK by wt tPA and impairment of autoregulation when administered 30 min after fluid percussion injury (FPI). We investigated the ability of variants that lack proteolytic activity but bind/block activation of NMDA-Rs by wt tPA (tPA-S(481)A), do not bind/block activation of NMDA-Rs but are proteolytic (tPA-A(296-299)), or neither bind/block NMDA-Rs nor are proteolytic (tPA-A(296-299)S(481)A) to prevent impairment of autoregulation after TBI and the role of MAPK and ET-1 in such effects. Results show that tPA-S(481)A given 3 h post-TBI, but not tPA-A(296-299) or tPA-A(296-299)S(481)A prevents impaired autoregulation by upregulating p38 and inhibiting ET-1, suggesting that tPA-S(481)A has a realistic therapeutic window and focuses intervention on NMDA-Rs to improve outcome.

Isolated head injury is a cause of shock in pediatric trauma patients

OBJECTIVES

Current trauma resuscitation protocols from the American College of Surgeons, Committee on Trauma, recommend intravascular volume expansion to treat shock after major trauma, assuming that hemorrhage is present. However, this assumption may not be correct. The purpose of this study was to identify the proportion of children with severe shock after trauma presenting with isolated head injury versus hemorrhagic injury.

METHODS

A retrospective review of all pediatric trauma patients (aged 0-15 years) was conducted over a 5-year period. Severe shock was defined as the presence of both an elevated blood lactate level and low blood pressure for age. Traumatic injuries were classified as hemorrhagic injuries, head injuries, combined hemorrhagic and head injuries, or other injuries, by analyzing International Classification of Diseases, Ninth Revision diagnostic codes.

RESULTS

A total of 31 (5%) of 680 pediatric trauma patients presented with severe shock. Among these 31 pediatric trauma patients, 9 (29%) had isolated head injury. Isolated head injury among children with shock was most frequently observed among children younger than 5 years (50%), and a decreased trend was noted with increasing age (23% for children 5-11 years and 0% for children 12-15 years [P = 0.03, Cochran-Armitage exact trend test]).

CONCLUSIONS

Isolated head injury was observed in 29% of children 0 to 15 years of age with severe shock after trauma and in 50% of children younger than 5 years. Head injury is an important cause of severe shock in pediatric trauma, particularly among young children.

High-dose barbiturates for refractory intracranial hypertension in children with severe traumatic brain injury

OBJECTIVES

To evaluate high-dose barbiturates as a second-tier therapy for pediatric refractory intracranial hypertension complicating severe traumatic brain injury.

DESIGN

This is a retrospective cohort study of children with refractory intracranial hypertension treated with high-dose barbiturates.

SETTING

A single center level I pediatric trauma from 2001 to 2010.

PATIENTS

Thirty-six children with refractory intracranial hypertension defined as intracranial pressure greater than 20 mm Hg despite standard management treated with high-dose barbiturates after severe traumatic brain injury.

INTERVENTIONS

High-dose barbiturates were administered for refractory intracranial hypertension for a minimum duration of 6 hours and monitored by continuous electroencephalography.

MEASUREMENTS AND MAIN RESULTS

Exposure was control of refractory intracranial hypertension defined as > 20 mm Hg within 6 hours after starting barbiturates. Pediatric cerebral performance category scores at hospital discharge and at 3 months (or longer) follow-up were the primary outcomes. Ten of 36 patients (28%) had control of refractory intracranial hypertension. Neither demographic nor injury characteristics were associated with refractory intracranial hypertension control. Children who responded received barbiturates significantly later after injury (76 vs. 29 median hours). Overall, 14 children died, 13 without control of intracranial pressure. Survival was more common in those who responded compared with those who did not respond to high-dose barbiturates, although this did not reach statistical significance (relative risk of death 0.2; 95% confidence interval; [0.03-1.3]). Of the 22 survivors, 19 had an acceptable survival (pediatric cerebral performance category less than 3) at 3 months or longer after injury; however, only three returned to normal function. Among survivors, control of refractory intracranial hypertension was associated with significantly better pediatric cerebral performance category scores and over two-fold likelihood of acceptable long-term outcome (relative risk 2.3; 95% confidence interval [1.4-4.0]) compared with uncontrolled refractory intracranial hypertension despite high-dose barbiturates.

CONCLUSIONS

Addition of high-dose barbiturates achieved control of refractory intracranial hypertension in almost 30% of treated children. Control of refractory intracranial hypertension was associated with increased likelihood of an acceptable long-term outcome.

Variation in intracranial pressure monitoring and outcomes in pediatric traumatic brain injury

OBJECTIVES

To describe between-hospital and patient-level variation in intracranial pressure (ICP) monitoring and to evaluate ICP monitoring in association with hospital features and outcome in children with traumatic brain injury (TBI).

DESIGN

Retrospective cohort study. SETTING Children's hospitals participating in the Pediatric Health Information System database (January 2001 to June 2011).

PARTICIPANTS

Children (aged <18 years) with TBI and head Abbreviated Injury Scale scores of at least 3 who were ventilated for at least 96 consecutive hours or who died in the first 4 days after hospital admission.

MAIN OUTCOME MEASURES

Monitoring of ICP.

RESULTS

A total of 4667 children met the study criteria. Hospital mortality was 41% (n = 1919). Overall, 55% of patients (n = 2586) received ICP monitoring. Expected hospital ICP monitoring rates after adjustment for patient age, cardiac arrest, inflicted injury, craniotomy or craniectomy, head Abbreviated Injury Scale score, and Injury Severity Score were 47% to 60%. Observed hospital ICP monitoring rates were 14% to 83%. Hospitals with more observed ICP monitoring, relative to expected, and hospitals with higher patient volumes had lower rates of mortality or severe disability. After adjustment for between-hospital variation and patient severity of injury, ICP monitoring was independently associated with age 1 year and older (odds ratio, 3.1; 95% CI, 2.5-3.8) vs age younger than 1 year.

CONCLUSIONS

There was significant between-hospital variation in ICP monitoring that cannot be attributed solely to differences in case mix. Hospitals that monitor ICP more frequently and hospitals with higher patient volumes had better patient outcomes. Infants with TBI are less likely to receive ICP monitoring than are older children.

Osmolar therapy in pediatric traumatic brain injury

OBJECTIVES

To describe patterns of use for mannitol and hypertonic saline in children with traumatic brain injury, to evaluate any potential associations between hypertonic saline and mannitol use and patient demographic, injury, and treatment hospital characteristics, and to determine whether the 2003 guidelines for severe pediatric traumatic brain injury impacted clinical practice regarding osmolar therapy.

DESIGN

Retrospective cohort study.

SETTING

Pediatric Health Information System database, January, 2001 to December, 2008.

PATIENTS

Children (age <18 yrs) with traumatic brain injury and head/neck Abbreviated Injury Scale score ≥ 3 who received mechanical ventilation and intensive care.

INTERVENTIONS

: None.

MEASUREMENTS AND MAIN RESULTS

The primary outcome was hospital billing for parenteral hypertonic saline and mannitol use, by day of service. Overall, 33% (2,069 of 6,238) of the patients received hypertonic saline, and 40% (2,500 of 6,238) received mannitol. Of the 1,854 patients who received hypertonic saline or mannitol for ≥ 2 days in the first week of therapy, 29% did not have intracranial pressure monitoring. After adjustment for hospital-level variation, primary insurance payer, and overall injury severity, use of both drugs was independently associated with older patient age, intracranial hemorrhage (other than epidural), skull fracture, and higher head/neck injury severity. Hypertonic saline use increased and mannitol use decreased with publication of the 2003 guidelines, and these trends continued through 2008.

CONCLUSIONS

Hypertonic saline and mannitol are used less in infants than in older children. The patient-level and hospital-level variation in osmolar therapy use and the substantial amount of sustained osmolar therapy without intracranial pressure monitoring suggest opportunities to improve the quality of pediatric traumatic brain injury care. With limited high-quality evidence available, published expert guidelines appear to significantly impact clinical practice in this area.

tPA contributes to impaired NMDA cerebrovasodilation after traumatic brain injury through activation of JNK MAPK

OBJECTIVE

N-methyl-D-aspartate (NMDA)-induced pial artery dilation (PAD) is reversed to vasoconstriction after fluid percussion brain injury (FPI). Tissue type plasminogen activator (tPA) is up-regulated and the tPA antagonist, EEIIMD, prevents impaired NMDA PAD after FPI. Mitogen-activated protein kinase (MAPK), a family of at least three kinases, ERK, p38, and JNK, is also up-regulated after traumatic brain injury (TBI). We hypothesize that tPA impairs NMDA-induced cerebrovasodilation after FPI in a MAPK isoform-dependent mechanism.

METHODS

Lateral FPI was induced in newborn pigs. The closed cranial window technique was used to measure pial artery diameter and to collect cerebrospinal fluid (CSF). ERK, p38, and JNK MAPK concentrations in CSF were quantified by ELISA.

RESULTS

CSF JNK MAPK was increased by FPI, increased further by tPA, but blocked by JNK antagonists SP600125 and D-JNKI1. FPI modestly increased p38 and ERK isoforms of MAPK. NMDA-induced PAD was reversed to vasoconstriction after FPI, whereas dilator responses to papaverine were unchanged. tPA, in post-FPI CSF concentration, potentiated NMDA-induced vasoconstriction while papaverine dilation was unchanged. SP 600125 and D-JNKI1, blocked NMDA-induced vasoconstriction and fully restored PAD. The ERK antagonist U 0126 partially restored NMDA-induced PAD, while the p38 inhibitor SB203580 aggravated NMDA-induced vasoconstriction observed in the presence of tPA after FPI.

DISCUSSION

These data indicate that tPA contributes to impairment of NMDA-mediated cerebrovasodilation after FPI through JNK, while p38 may be protective. These data suggest that inhibition of the endogenous plasminogen activator system and JNK may improve cerebral hemodynamic outcome post-TBI.

Phenylephrine infusion prevents impairment of ATP- and calcium-sensitive potassium channel-mediated cerebrovasodilation after brain injury in female, but aggravates impairment in male, piglets through modulation of ERK MAPK upregulation

Traumatic brain injury (TBI) contributes to morbidity in children and boys, and hypotension worsens outcome. Extracellular signal-related kinase (ERK) mitogen-activated protein kinase (MAPK) is upregulated more in males and reduces cerebral blood flow (CBF) after fluid percussion injury (FPI). Increased cerebral perfusion pressure (CPP) via phenylephrine (Phe) sex-dependently improves impairment of the cerebral autoregulation seen after FPI through modulation of ERK MAPK upregulation, which is aggravated in males, but is blocked in females. Activation of ATP- and calcium-sensitive (Katp and Kca) channels produces cerebrovasodilation and contributes to autoregulation, both of which are impaired after FPI. Using piglets equipped with a closed cranial window, we hypothesized that potassium channel functional impairment after FPI is prevented by Phe in a sex-dependent manner through modulation of ERK MAPK upregulation. The Katp and Kca agonists cromakalim and NS 1619 produced vasodilation that was impaired after FPI more in males than in females. Phe prevented reductions in cerebrovasodilation after cromakalim and NS 1619 in females, but reduced dilation after these potassium channel agonists were given to males after FPI. Co-administration of U 0126, an ERK antagonist, and Phe fully restored dilation to cromakalim, calcitonin gene-related peptide (CGRP), and NS 1619, in males after FPI. These data indicate that Phe sex-dependently prevents impairment of Katp and Kca channel-mediated cerebrovasodilation after FPI in females, but aggravates impairment in males, through modulation of ERK MAPK upregulation. Since autoregulation of CBF is dependent on intact functioning of potassium channels, these data suggest a role for sex-dependent mechanisms in the treatment of cerebral autoregulation impairment after pediatric TBI.

Impaired cerebral blood flow autoregulation during posttraumatic arterial hypotension after fluid percussion brain injury is prevented by phenylephrine in female but exacerbated in male piglets by extracellular signal-related kinase mitogen-activated protein kinase upregulation

OBJECTIVE

Traumatic brain injury contributes to morbidity and mortality in children and boys are disproportionately represented. Hypotension is common and worsens outcome after traumatic brain injury. Extracellular signal-related kinase mitogen-activated protein kinase is upregulated and reduces cerebral blood flow after fluid percussion brain injury in piglets. We hypothesized that increased cerebral perfusion pressure through phenylephrine sex dependently reduces impairment of cerebral autoregulation during hypotension after fluid percussion brain injury through modulation of extracellular signal-related kinase mitogen-activated protein kinase.

DESIGN

Prospective, randomized animal study.

SETTING

University laboratory.

SUBJECTS

Newborn (1- to 5-day-old) pigs.

INTERVENTIONS

Cerebral blood flow, pial artery diameter, intracranial pressure, and autoregulatory index were determined before and after fluid percussion brain injury in untreated, preinjury, and postinjury phenylephrine (1 microg/kg/min intravenously) treated male and female pigs during normotension and hemorrhagic hypotension. Cerebrospinal fluid extracellular signal-related kinase mitogen-activated protein kinase was determined by enzyme-linked immunosorbent assay.

MEASUREMENTS AND MAIN RESULTS

Reductions in pial artery diameter, cerebral blood flow, cerebral perfusion pressure, and elevated intracranial pressure after fluid percussion brain injury were greater in males, which were blunted by phenylephrine pre- or postfluid percussion brain injury. During hypotension and fluid percussion brain injury, pial artery dilation was impaired more in males. Phenylephrine decreased impairment of hypotensive pial artery dilation after fluid percussion brain injury in females, but paradoxically caused vasoconstriction after fluid percussion brain injury in males. Papaverine-induced pial artery vasodilation was unchanged by fluid percussion brain injury and phenylephrine. Cerebral blood flow, cerebral perfusion pressure, and autoregulatory index decreased markedly during hypotension and fluid percussion brain injury in males but less in females. Phenylephrine prevented reductions in cerebral blood flow, cerebral perfusion pressure, and autoregulatory index during hypotension in females but increased reductions in males. Cerebrospinal fluid extracellular signal-related kinase mitogen-activated protein kinase was increased more in males than females after fluid percussion brain injury. Phenylephrine blunted extracellular signal-related kinase mitogen-activated protein kinase upregulation in females but increased extracellular signal-related kinase mitogen-activated protein kinase upregulation in males after fluid percussion brain injury.

CONCLUSIONS

These data indicate that elevation of cerebral perfusion pressure with phenylephrine sex dependently prevents impairment of cerebral autoregulation during hypotension after fluid percussion brain injury through modulation of extracellular signal-related kinase mitogen-activated protein kinase. These data suggest the potential role for sex-dependent mechanisms in cerebral autoregulation after pediatric traumatic brain injury.

Adrenomedullin prevents sex-dependent impairment of autoregulation during hypotension after piglet brain injury through inhibition of ERK MAPK upregulation

Cerebrospinal fluid (CSF) adrenomedullin (ADM) levels are increased in female, but remain unchanged in male, piglets after fluid percussion injury (FPI) of the brain. Subthreshold vascular concentrations of ADM restore impaired hypotensive pial artery dilation after FPI more in males than females. Extracellular signal-related kinase (ERK) mitogen-activated protein kinase (MAPK) is upregulated and contributes to reductions in cerebral blood flow (CBF) after FPI. We hypothesized that ADM prevents sex-dependent impairment of autoregulation during hypotension after FPI through inhibition of ERK MAPK upregulation. FPI increased ERK MAPK more in males than in females. CBF was unchanged during hypotension in sham animals, was reduced more in males than in females after FPI during normotension, and was further reduced in males than in females during hypotension and after FPI. ADM and the ERK MAPK antagonist U 0126 prevented reductions in CBF during hypotension and FPI more in males than in females. Transcranial Doppler (TCD) blood flow velocity was unchanged during hypotension in sham animals, was decreased during hypotension and FPI in male but not in female pigs, and was ameliorated by ADM. Intracranial pressure (ICP) was increased after FPI more in male than in female animals. ADM blunted elevated ICP during FPI and hypotension in males, but not in females. ADM prevented reductions in cerebral perfusion pressure (CPP) during FPI and hypotension in males but not in females. The calculated autoregulatory index was unchanged during hypotension in sham animals, but was reduced more in males than females during hypotension and FPI. ADM prevented reductions in autoregulation during hypotension and FPI more in males than females. These data indicate that ADM prevented loss of cerebral autoregulation after FPI in a sex-dependent and ERK MAPK-dependent manner.

SNP improves cerebral hemodynamics during normotension but fails to prevent sex dependent impaired cerebral autoregulation during hypotension after brain injury

Traumatic brain injury (TBI) is a leading cause of morbidity in children and boys are disproportionately represented. Hypotension is common and worsens outcome after TBI. Previous studies show that adrenomedullin, a cerebrovasodilator, prevented sex dependent impairment of autoregulation during hypotension after piglet fluid percussion brain injury (FPI). We hypothesized that this concept was generalizable and that administration of another vasodilator, sodium nitroprusside (SNP), may equally improve CBF and cerebral autoregulation in a sex dependent manner after FPI. SNP produced equivalent percent cerebrovasodilation in male and female piglets. Reductions in pial artery diameter, cortical CBF, and cerebral perfusion pressure (CPP) concomitant with elevated intracranial pressure (ICP) after FPI were greater in male compared to female piglets during normotension which was blunted by SNP. During hypotension, pial artery dilation (PAD) was impaired more in the male than the female after FPI. However, SNP did not improve hypotensive PAD after FPI in females and paradoxically caused vasoconstriction in males. SNP did not prevent reductions in CBF, CPP or autoregulatory index during combined hypotension and FPI in either sex. SNP aggravated ERK MAPK upregulation after FPI. These data indicate that despite prevention of reductions in CBF after FPI, SNP does not prevent impairment of autoregulation during hypotension after FPI. These data suggest that therapies directed at a purely hemodynamic increase in CPP will fail to improve outcome during combined TBI and hypotension.

The availability and use of out-of-hospital physiologic information to identify high-risk injured children in a multisite, population-based cohort

OBJECTIVE

The validity of using adult physiologic criteria to triage injured children in the out-of-hospital setting remains unproven. Among children meeting adult field physiologic criteria, we assessed the availability of physiologic information, the incidence of death or prolonged hospitalization, and whether age-specific criteria would improve the specificity of the physiologic triage step.

METHODS

We analyzed a prospective, out-of-hospital cohort of injured children aged < or =14 years collected from December 2005 through February 2007 by 237 emergency medical services (EMS) agencies transporting to 207 acute care hospitals (trauma and nontrauma centers) in 11 sites across the United States and Canada. Inclusion criteria were standard adult physiologic values: systolic blood pressure (SBP) < or =90 mmHg, respiratory rate < 10 or > 29 breaths/min, Glasgow Coma Scale (GCS) score < or =12, and field intubation attempt. Seven physiologic variables (including age-specific values) and three demographic and mechanism variables were included in the analysis. "High-risk" children included those who died (field or in-hospital) or were hospitalized > 2 days. The decision tree was derived and validated using binary recursive partitioning.

RESULTS

Nine hundred fifty-five children were included in the analysis, of whom 62 (6.5%) died and 117 (12.3%) were hospitalized > 2 days. Missing values were common, ranging from 6% (respiratory rate) to 53% (pulse oximetry), and were associated with younger age and high-risk outcome. The final decision rule included four variables (assisted ventilation, GCS score < 11, pulse oximetry < 95%, and SBP > 96 mmHg), which demonstrated improved specificity (71.7% [95% confidence interval (CI) 66.7-76.6%]) at the expense of missing high-risk children (sensitivity 76.5% [95% CI 66.4-86.6%]).

CONCLUSIONS

The incidence of high-risk injured children meeting adult physiologic criteria is relatively low and the findings from this sample do not support using age-specific values to better identify such children. However, the amount and pattern of missing data may compromise the value and practical use of field physiologic information in pediatric triage.

Severity of head computed tomography scan findings fail to explain racial differences in mortality following child abuse

INTRODUCTION

Differences in head injury severity may not be fully appreciated in child abuse victims. The purpose of this study was to determine if differential findings on initial head computed tomography (CT) scan could explain observed differential outcome by race.

METHODS

We identified 164 abuse patients from our trauma registry with an Injury Severity Score (ISS) > or = 15. Their initial head CT scan was graded from 1 to 4 (normal to severe). Statistical analysis was performed to asses the correlation between race, head CT grade, Glasgow Coma Scale (GCS) score, and mortality.

RESULTS

Overall mortality was 17%: 11% for white children, 32% for African-American children (P < .05). In review of the head CT scans there was no difference by race in types of injuries or head CT grade. Using a multivariate regression model, African-American race remained an independent risk factor for mortality with an odd ratio of 4.3 (95% confidence interval [CI] 1.6-11.5).

CONCLUSION

African-American children had a significantly higher mortality rate despite similar findings on initial head CT scans. Factors other than injury severity may explain these disparate outcomes.

Early prediction of posttraumatic in-hospital mortality in pediatric patients

BACKGROUND

The purpose of this study was to develop a triaging tool to predict pediatric in-hospital mortality from data available soon after emergency department (ED) presentation.

METHODS

The study group consisted of patients of less than 18 years of age from the National Trauma Data Bank with a reported in-hospital mortality status. Variables analyzed were (1) patient demographics, (2) Glasgow Coma Scale (GCS) values, (3) ED vital signs, (4) injury mechanism, and (5) number of days from trauma until admission. Chi-square-assisted interaction detection (CHAID) profiled patient subgroups. The final cohort was randomly divided into 2 equal sets: a training set to subgroup patients and a testing set to validate the prediction accuracy.

RESULTS

The cohort consisted of 224,628 patients with 2.29% in-hospital mortality. Sixteen of 19 potential variables were associated with increased risk of in-hospital mortality. The relative risk of dying was 61.7 times greater (95% confidence interval 57.5-66.1) when CHAID predicted mortality relative to when the model predicted survival (P<0.0001). The most powerful variables of the CHAID model were low total GCS scores and systolic blood pressure in the ED. The CHAID model had an improved relative risk and a better combination of sensitivity and positive predictive value compared with GCS and systolic blood pressure in predicting mortality.

CONCLUSIONS

The risk of in-hospital mortality for injured children may be identified soon after arrival in the ED. This information may be used by frontline providers to appropriately triage patients to pediatric trauma centers quickly, to guide resuscitation, and for teaching purposes.

Cerebral hemodynamic predictors of poor 6-month Glasgow Outcome Score in severe pediatric traumatic brain injury

Little is known regarding the cerebral autoregulation in pediatric traumatic brain injury (TBI). We examined the relationship between cerebral hemodynamic predictors, including cerebral autoregulation, and long-term outcome after severe pediatric TBI. After Institutional Review Board (IRB) approval, a retrospective analysis of prospectively collected data (May 2002 to October 2007) for children age < or =16 years with severe TBI (admission Glasgow Coma Scale [GCS] score <9) was performed. Cerebral autoregulation was assessed within 72 h after TBI. Cerebral hemodynamic predictors (intracranial pressure [ICP], systolic blood pressure [SBP], and cerebral perfusion pressure [CPP]) through the first 72 h after TBI were abstracted. Univariate and multivariate analyses examined the relationship between impaired cerebral autoregulation (autoregulatory index <0.4), intracranial hypertension (ICP >20 mm Hg), and hypotension (SBP <5th percentile and CPP <40 mm Hg). Six-month Glasgow Outcome Scale (GOS) score of <4 defined poor outcome. Ten (28%) of the 36 children examined (9.1 +/- 5.3 [0.8-16] years; 74% male) had poor outcome. Univariate factors associated with poor outcome were impaired cerebral autoregulation (p = 0.005), SBP <5(th) percentile for age and gender (p = 0.02), and low middle cerebral artery flow velocity (<2 SD for age and gender; p = 0.04). Independent risk factors for poor 6-month GOS were impaired cerebral autoregulation (adjusted odds ratio [aOR] 12.0; 95% confidence interval [CI] 1.4-99.4) and hypotension (SBP <5th percentile; aOR 8.8; 95% CI 1.1-70.5), respectively. Previous studies of TBI describing poor outcome with hemodynamics did not consider the status of cerebral autoregulation. In this study, both impaired cerebral autoregulation and SBP <5th percentile were independent risk factors for poor 6-month GOS.

Mortality and functional morbidity after use of PALS/APLS by community physicians

OBJECTIVES

To test the hypothesis that pediatric shock is a common cause of death and functional morbidity and that pediatric advanced life support (PALS)/advanced pediatric life support (APLS) resuscitation in the community hospital setting improves child health outcomes.

METHODS

This study included all children consecutively transported to 5 regional, tertiary care children's hospitals over 4 years, and is a prospective cohort study comparing outcomes in children who did or did not receive PALS/APLS resuscitation in the community hospital.

RESULTS

Shock occurred in 37% of the patients transferred to the tertiary centers. Regardless of trauma status, children with shock had an increased mortality rate compared with those without shock (all patients: 11.4% vs 2.6%), trauma patients (28.3% vs 1.2%), and nontrauma patients (10.5% vs 2.8%). Early shock reversal was associated with reduced mortality (5.06% vs 16.37%) and functional morbidity (1.56% vs 4.11%) rates. Early use of PALS/APLS-recommended interventions was associated with reduced mortality (8.69% vs 15.01%) and functional morbidity (1.24% vs 4.23%) rates. After controlling for center, severity of illness, and trauma status, early reversal of shock and use of PALS/APLS-recommended interventions remained associated with reduced morbidity and mortality rates.

CONCLUSIONS

Shock is common in children who are transferred for tertiary care. Pediatric shock recognition and resuscitation in the community hospital improves survival and functional outcome regardless of diagnostic category. The development of shock/trauma systems for children with and without trauma seems prudent.

Early resuscitation of children with moderate-to-severe traumatic brain injury

OBJECTIVES

Traumatic brain injury is a leading cause of death and disability in children. Guidelines have been established to prevent secondary brain injury caused by hypotension or hypoxia. The purpose of this study was to identify the prevalence, monitoring, and treatment of hypotension and hypoxia during "early" (prehospital and emergency department) care and to evaluate their relationship to vital status and neurologic outcomes at hospital discharge.

METHODS

This was a retrospective study of 299 children with moderate-to-severe traumatic brain injury presenting to a level 1 pediatric trauma center. We recorded vital signs and medical provider response to hypotension and/or hypoxia during all portions of early care.

RESULTS

Blood pressure (31%) and oxygenation (34%) were not recorded during some portion of "early care." Documented hypotension occurred in 118 children (39%). An attempt to treat documented hypotension was made in 48% (57 of 118 children). After adjusting for severity of illness, children who did not receive an attempt to treat hypotension had an increased odds of death of 3.4 and were 3.7 times more likely to suffer disability compared with treated hypotensive children. Documented hypoxia occurred in 131 children (44%). An attempt to treat hypoxia was made in 92% (121 of 131 children). Untreated hypoxia was not significantly associated with death or disability, except in the setting of hypotension.

CONCLUSIONS

Hypotension and hypoxia are common events in pediatric traumatic brain injury. Approximately one third of children are not properly monitored in the early phases of their management. Attempts to treat hypotension and hypoxia significantly improved outcomes.

New concepts in treatment of pediatric traumatic brain injury

Emerging evidence suggests unique age-dependent responses following pediatric traumatic brain injury. The anesthesiologist plays a pivotal role in the acute treatment of the head-injured pediatric patient. This review provides important updates on the pathophysiology, diagnosis, and age-appropriate acute management of infants and children with severe traumatic brain injury. Areas of important clinical and basic science investigations germane to the anesthesiologist, such as the role of anesthetics and apoptosis in the developing brain, are discussed.

[Hypotension and adverse transfusion reactions: from the associated clinical signs to the hypotensive transfusion reaction]

OBJECTIVE

The first aim of this study was to confirm the presence of hypotension blood transfusion reactions and to assess the part of hypotension as a principal event, as defined by the literature but not characterized in French haemovigilance data. As well, recent series of several cases led us to consider a possible incidence increase.

STUDY DESIGN

Using a retrospective observation, the haemovigilance data from 2000 to the end of 2007 of two French regions were reviewed. During this period, 1159657 blood units were transfused by nearly 100 hospitals and 3727 adverse reactions observed.

RESULTS

One hundred and sixty-eight adverse reactions with hypotension were noticed and analyzed, representing 4.5% of all transfusion reactions and revealing an incidence of 14.5 for 100000 blood units transfused. It turned out to be mostly male recipients, severe reactions and appearing rather in the beginning of transfusions. Although platelets having greater incidence, all types of blood products may be involved. The clinical diagnosis was the following: 40 to 47% were classified as febrile reactions, 13 to 17% were allergic reactions, 8 to 9% were due to immunologic and/or haemolytic reactions, 5 to 7% resulted of cardiologic disorders, 5% resulted of hypovolemic contexts and 22% were unexplained hypotensive transfusion reactions.

CONCLUSION

In about three cases out of four, transfusion-induced hypotension was associated with other clinical reactions. Indeed, hypotensive transfusion reactions were identified, having an incidence of 3.2 for 100000 blood units transfused. Furthermore, there was no explanation found for the incidence increase in our region during 2007. A national study was suggested to analyse the national data as well as a prospective study to clear out this type of transfusion reactions.

Incidence and risk factors for preincision hypotension in a noncardiac pediatric surgical population

BACKGROUND

Routine monitoring of blood pressure is an essential part of perioperative care in adults and children. It is however not known whether intraoperative hypotension (IOH) is clinically important in the 'healthy' pediatric patient. This may be partly due to the lack of data on the incidence and consequences of IOH in this group of patients. We utilized the Brain Trauma Foundation definition of hypotension to describe the incidence of preincision hypotension (PIH) in a large pediatric noncardiac surgical population and identified risk factors for the occurrence PIH.

METHODS

We examined the electronic perioperative records of all children aged 1-17 years undergoing general anesthesia for noncardiac surgeries between January 2005 and June 2007 in our institution. Frequency and factors associated with PIH were computed. Binary logistic regression with forward step-wise algorithm was used to examine factors associated with PIH.

RESULTS

There were 22,263 children of whom 57.6% were males. Most (94.9%) cases were elective, American Society of Anesthesiologists (ASA) I-II (79.5%) procedures. Inhalational induction was predominantly used in this cohort (67%) although 33% of patients had propofol either as a sole induction agent or as part of a 'co-induction' regime. Single or multiple episodes of PIH occurred in 35.8% of patients. PIH was more common in patients with ASA > or = III (P < 0.001); those with preoperative hypotension (P < 0.001); and following intravenous induction (P < 0.001) as well as propofol co-induction (P < 0.001). On multivariate analysis the following were significant predictors of PIH: baseline hypotension, propofol co-induction, age, ASA > or = III, and long preincision period.

CONCLUSION

Preincision hypotension is common in the pediatric surgical population undergoing general anesthesia. Factors independently predictive of PIH included high ASA status, pre-existing hypotension, propofol co-induction prolonged preincision period and adolescent age group. The importance of blood pressure monitoring, prompt recognition of hypotension and use of appropriate intervention is emphasized.

Does adherence to treatment targets in children with severe traumatic brain injury avoid brain hypoxia? A brain tissue oxygenation study

OBJECTIVE

Most physicians rely on conventional treatment targets for intracranial pressure, cerebral perfusion pressure, systemic oxygenation, and hemoglobin to direct management of traumatic brain injury (TBI) in children. In this study, we used brain tissue oxygen tension (PbtO2) monitoring to examine the association between PbtO2 values and outcome in pediatric severe TBI and to determine the incidence of compromised PbtO2 in patients for whom acceptable treatment targets had been achieved.

METHODS

In this prospective observational study, 26 children with severe TBI and a median postresuscitation Glasgow Coma Scale score of 5 were managed with continuous PbtO2 monitoring. The relationships between outcome and the 6-hour period of lowest PbtO2 values and the length of time that PbtO2 was less than 20, 15, 10, and 5 mmHg were examined. The incidence of reduced PbtO2 for each threshold was evaluated where the following targets were met: intracranial pressure less than 20 mmHg, cerebral perfusion pressure greater than 50 mmHg, arterial oxygen tension greater than 60 mmHg (and peripheral oxygen saturation > 90%), and hemoglobin greater than 8 g/dl.

RESULTS

There was a significant association between poor outcome and the 6-hour period of lowest PbtO2 and length of time that PbtO2 was less than 15 and 10 mmHg. Multiple logistic regression analysis showed that low PbtO2 had an independent association with poor outcome. Despite achieving the management targets described above, 80% of patients experienced one or more episodes of compromised PbtO2 (< 20 mmHg), and almost one-third experienced episodes of brain hypoxia (PbtO2 < 10 mmHg).

CONCLUSION

Reduced PbtO2 is associated with poor outcome in pediatric severe TBI. In addition, many patients experience episodes of compromised PbtO2 despite achieving acceptable treatment targets.

Acute clinical grading in pediatric severe traumatic brain injury and its association with subsequent intracranial pressure, cerebral perfusion pressure, and brain oxygenation

Object

The goal of this paper was to examine the relationship between methods of acute clinical assessment and measures of secondary cerebral insults in severe traumatic brain injury in children.

Methods

Patients who underwent intracranial pressure (ICP), cerebral perfusion pressure (CPP), and brain oxygenation (PbtO2) monitoring and who had an initial Glasgow Coma Scale score, Pediatric Trauma Score, Pediatric Index of Mortality 2 score, and CT classification were evaluated. The relationship between these acute clinical scores and secondary cerebral insult measures, including ICP, CPP, PbtO2, and systemic hypoxia were evaluated using univariate and multivariate analysis.

Results

The authors found significant associations between individual acute clinical scores and select physiological markers of secondary injury. However, there was a large amount of variability in these results, and none of the scores evaluated predicted each and every insult. Furthermore, a number of physiological measures were not predicted by any of the scores.

Conclusions

Although they may guide initial treatment, grading systems used to classify initial injury severity appear to have a limited value in predicting who is at risk for secondary cerebral insults.