Pediatric Moyamoya Revascularization Perioperative Care: A Modified Delphi Study.

BACKGROUND: Surgical revascularization decreases the long-term risk of stroke in children with moyamoya arteriopathy but can be associated with an increased risk of stroke during the perioperative period. Evidence-based approaches to optimize perioperative management are limited and practice varies widely. Using a modified Delphi process, we sought to establish expert consensus on key components of the perioperative care of children with moyamoya undergoing indirect revascularization surgery and identify areas of equipoise to define future research priorities. METHODS: Thirty neurologists, neurosurgeons, and intensivists practicing in North America with expertise in the management of pediatric moyamoya were invited to participate in a three-round, modified Delphi process consisting of a 138-item practice patterns survey, anonymous electronic evaluation of 88 consensus statements on a 5-point Likert scale, and a virtual group meeting during which statements were discussed, revised, and reassessed. Consensus was defined as ≥ 80% agreement or disagreement. RESULTS: Thirty-nine statements regarding perioperative pediatric moyamoya care for indirect revascularization surgery reached consensus. Salient areas of consensus included the following: (1) children at a high risk for stroke and those with sickle cell disease should be preadmitted prior to indirect revascularization; (2) intravenous isotonic fluids should be administered in all patients for at least 4 h before and 24 h after surgery; (3) aspirin should not be discontinued in the immediate preoperative and postoperative periods; (4) arterial lines for blood pressure monitoring should be continued for at least 24 h after surgery and until active interventions to achieve blood pressure goals are not needed; (5) postoperative care should include hourly vital signs for at least 24 h, hourly neurologic assessments for at least 12 h, adequate pain control, maintaining normoxia and normothermia, and avoiding hypotension; and (6) intravenous fluid bolus administration should be considered the first-line intervention for new focal neurologic deficits following indirect revascularization surgery. CONCLUSIONS: In the absence of data supporting specific care practices before and after indirect revascularization surgery in children with moyamoya, this Delphi process defined areas of consensus among neurosurgeons, neurologists, and intensivists with moyamoya expertise. Research priorities identified include determining the role of continuous electroencephalography in postoperative moyamoya care, optimal perioperative blood pressure and hemoglobin targets, and the role of supplemental oxygen for treatment of suspected postoperative ischemia.

Acute management of childhood stroke.

PURPOSE OF REVIEW: The purpose of this paper is to review recent updates in the acute management of childhood arterial ischemic stroke, including reperfusion therapies and neuroprotective measures. RECENT FINDINGS: With the emergence of pediatric stroke centers in recent years, processes facilitating rapid diagnosis and treatment have resulted in improved implementation of early targeted neuroprotective measures as well as the increased use of reperfusion therapies in childhood arterial ischemic stroke. Retrospective data has demonstrated that alteplase is safe in carefully selected children with arterial ischemic stroke in the first 4.5 h from symptom onset, though data regarding its efficacy in children are still lacking. There is also increasing data that suggests that thrombectomy in children with large vessel occlusion improves functional outcomes. Recent adult studies, including the use of Tenecteplase as an alteplase alternative and expansion of late thrombectomy to include patients with large ischemic cores, also are reviewed along with limitations to application of the adult data to pediatric care. SUMMARY: There have been significant advances in the hyperacute care of children with ischemic stroke and early diagnosis and targeted management are of the upmost importance in improving long-term outcomes.

Assessment of Brain Magnetic Resonance and Spectroscopy Imaging Findings and Outcomes After Pediatric Cardiac Arrest.

Importance: Morbidity and mortality after pediatric cardiac arrest are chiefly due to hypoxic-ischemic brain injury. Brain features seen on magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) after arrest may identify injury and aid in outcome assessments. Objective: To analyze the association of brain lesions seen on T2-weighted MRI and diffusion-weighted imaging and N-acetylaspartate (NAA) and lactate concentrations seen on MRS with 1-year outcomes after pediatric cardiac arrest. Design, Setting, and Participants: This multicenter cohort study took place in pediatric intensive care units at 14 US hospitals between May 16, 2017, and August 19, 2020. Children aged 48 hours to 17 years who were resuscitated from in-hospital or out-of-hospital cardiac arrest and who had a clinical brain MRI or MRS performed within 14 days postarrest were included in the study. Data were analyzed from January 2022 to February 2023. Exposure: Brain MRI or MRS. Main Outcomes and Measures: The primary outcome was an unfavorable outcome (either death or survival with a Vineland Adaptive Behavior Scales, Third Edition, score of <70) at 1 year after cardiac arrest. MRI brain lesions were scored according to region and severity (0 = none, 1 = mild, 2 = moderate, 3 = severe) by 2 blinded pediatric neuroradiologists. MRI Injury Score was a sum of T2-weighted and diffusion-weighted imaging lesions in gray and white matter (maximum score, 34). MRS lactate and NAA concentrations in the basal ganglia, thalamus, and occipital-parietal white and gray matter were quantified. Logistic regression was performed to determine the association of MRI and MRS features with patient outcomes. Results: A total of 98 children, including 66 children who underwent brain MRI (median [IQR] age, 1.0 [0.0-3.0] years; 28 girls [42.4%]; 46 White children [69.7%]) and 32 children who underwent brain MRS (median [IQR] age, 1.0 [0.0-9.5] years; 13 girls [40.6%]; 21 White children [65.6%]) were included in the study. In the MRI group, 23 children (34.8%) had an unfavorable outcome, and in the MRS group, 12 children (37.5%) had an unfavorable outcome. MRI Injury Scores were higher among children with an unfavorable outcome (median [IQR] score, 22 [7-32]) than children with a favorable outcome (median [IQR] score, 1 [0-8]). Increased lactate and decreased NAA in all 4 regions of interest were associated with an unfavorable outcome. In a multivariable logistic regression adjusted for clinical characteristics, increased MRI Injury Score (odds ratio, 1.12; 95% CI, 1.04-1.20) was associated with an unfavorable outcome. Conclusions and Relevance: In this cohort study of children with cardiac arrest, brain features seen on MRI and MRS performed within 2 weeks after arrest were associated with 1-year outcomes, suggesting the utility of these imaging modalities to identify injury and assess outcomes.

La Crosse Virus Neuroinvasive Disease in Children: A Contemporary Analysis of Clinical/Neurobehavioral Outcomes and Predictors of Disease Severity.

BACKGROUND: La Crosse virus (LACV) is the most common neuroinvasive arboviral infection in children in the United States. However, data regarding predictors of disease severity and neurologic outcome are limited. Additionally, long-term neurologic and neurobehavioral outcomes remain relatively sparse. METHODS: This was a single-center, retrospective cohort study, followed by recruitment for a cross-sectional analysis of long-term neurobehavioral outcomes, among children aged 0-18 years with proven or probable LACV neuroinvasive disease (LACV-ND) between January 2009 and December 2018. Case ascertainment was assured by International Classification of Diseases, Ninth and Tenth Revision, Clinical Modification codes cross-referenced with laboratory results detecting LACV. Demographics, diagnostics, radiographs, and outcomes were evaluated. Recruitment of patients with prior diagnosis of LACV-ND occurred from January 2020 to March 2020, with assessment performed by validated pediatric questionnaires. RESULTS: One-hundred fifty-two children (83 males; median age, 8 years [interquartile range, 5-11.5 years]) were diagnosed with proven (n = 61 [47%]) and probable (n = 91 [60%]) LACV-ND. Sixty-five patients (43%) had severe disease. Altered mental status (AMS) (odds ratio [OR], 6.36 [95% confidence interval {CI}, 2.03-19.95]; P = .0002) and seizures at presentation (OR, 10.31 [95% CI, 3.45-30.86]; P = .0001) were independent predictors of severe disease. Epileptiform discharges on electroencephalogram (EEG) were independently associated with epilepsy diagnosis at follow-up (OR, 13.45 [95% CI, 1.4-128.77]; P = .024). Fifty-four patients were recruited for long-term neurobehavioral follow-up, with frequent abnormal assessments identified (19%-54%) irrespective of disease severity. CONCLUSIONS: Severe disease was observed frequently among children with LACV-ND. Seizures and AMS at presentation were independent predictors of severe disease. EEG may help determine long-term epilepsy risk. Long-term neurobehavioral issues are frequent and likely underrecognized among children with LACV-ND.

Association of Blood-Based Brain Injury Biomarker Concentrations With Outcomes After Pediatric Cardiac Arrest.

Importance: Families and clinicians have limited validated tools available to assist in estimating long-term outcomes early after pediatric cardiac arrest. Blood-based brain-specific biomarkers may be helpful tools to aid in outcome assessment. Objective: To analyze the association of blood-based brain injury biomarker concentrations with outcomes 1 year after pediatric cardiac arrest. Design, Setting, and Participants: The Personalizing Outcomes After Child Cardiac Arrest multicenter prospective cohort study was conducted in pediatric intensive care units at 14 academic referral centers in the US between May 16, 2017, and August 19, 2020, with the primary investigators blinded to 1-year outcomes. The study included 120 children aged 48 hours to 17 years who were resuscitated after cardiac arrest, had pre-cardiac arrest Pediatric Cerebral Performance Category scores of 1 to 3 points, and were admitted to an intensive care unit after cardiac arrest. Exposure: Cardiac arrest. Main Outcomes and Measures: The primary outcome was an unfavorable outcome (death or survival with a Vineland Adaptive Behavior Scales, third edition, score of <70 points) at 1 year after cardiac arrest. Glial fibrillary acidic protein (GFAP), ubiquitin carboxyl-terminal esterase L1 (UCH-L1), neurofilament light (NfL), and tau concentrations were measured in blood samples from days 1 to 3 after cardiac arrest. Multivariate logistic regression and area under the receiver operating characteristic curve (AUROC) analyses were performed to examine the association of each biomarker with outcomes on days 1 to 3. Results: Among 120 children with primary outcome data available, the median (IQR) age was 1.0 (0-8.5) year; 71 children (59.2%) were male. A total of 5 children (4.2%) were Asian, 19 (15.8%) were Black, 81 (67.5%) were White, and 15 (12.5%) were of unknown race; among 110 children with data on ethnicity, 11 (10.0%) were Hispanic, and 99 (90.0%) were non-Hispanic. Overall, 70 children (58.3%) had a favorable outcome, and 50 children (41.7%) had an unfavorable outcome, including 43 deaths. On days 1 to 3 after cardiac arrest, concentrations of all 4 measured biomarkers were higher in children with an unfavorable vs a favorable outcome at 1 year. After covariate adjustment, NfL concentrations on day 1 (adjusted odds ratio [aOR], 5.91; 95% CI, 1.82-19.19), day 2 (aOR, 11.88; 95% CI, 3.82-36.92), and day 3 (aOR, 10.22; 95% CI, 3.14-33.33); UCH-L1 concentrations on day 2 (aOR, 11.27; 95% CI, 3.00-42.36) and day 3 (aOR, 7.56; 95% CI, 2.11-27.09); GFAP concentrations on day 2 (aOR, 2.31; 95% CI, 1.19-4.48) and day 3 (aOR, 2.19; 95% CI, 1.19-4.03); and tau concentrations on day 1 (aOR, 2.44; 95% CI, 1.14-5.25), day 2 (aOR, 2.28; 95% CI, 1.31-3.97), and day 3 (aOR, 2.04; 95% CI, 1.16-3.57) were associated with an unfavorable outcome. The AUROC models were significantly higher with vs without the addition of NfL on day 2 (AUROC, 0.932 [95% CI, 0.877-0.987] vs 0.871 [95% CI, 0.793-0.949]; P = .02) and day 3 (AUROC, 0.921 [95% CI, 0.857-0.986] vs 0.870 [95% CI, 0.786-0.953]; P = .03). Conclusions and Relevance: In this cohort study, blood-based brain injury biomarkers, especially NfL, were associated with an unfavorable outcome at 1 year after pediatric cardiac arrest. Additional evaluation of the accuracy of the association between biomarkers and neurodevelopmental outcomes beyond 1 year is needed.

Use of Magnetic Resonance Imaging in Neuroprognostication After Pediatric Cardiac Arrest: Survey of Current Practices.

BACKGROUND: Use of magnetic resonance imaging (MRI) as a tool to aid in neuroprognostication after cardiac arrest (CA) has been described, yet details of specific indications, timing, and sequences are unknown. We aim to define the current practices in use of brain MRI in prognostication after pediatric CA. METHODS: A survey was distributed to pediatric institutions participating in three international studies. Survey questions related to center demographics, clinical practice patterns of MRI after CA, neuroimaging resources, and details regarding MRI decision support. RESULTS: Response rate was 31% (44 of 143). Thirty-four percent (15 of 44) of centers have a clinical pathway informing the use of MRI after CA. Fifty percent (22 of 44) of respondents reported that an MRI is obtained in nearly all patients with CA, and 32% (14 of 44) obtain an MRI in those who do not return to baseline neurological status. Poor neurological examination was reported as the most common factor (91% [40 of 44]) determining the timing of the MRI. Conventional sequences (T1, T2, fluid-attenuated inversion recovery, and diffusion-weighted imaging/apparent diffusion coefficient) are routinely used at greater than 97% of centers. Use of advanced imaging techniques (magnetic resonance spectroscopy, diffusion tensor imaging, and functional MRI) were reported by less than half of centers. CONCLUSIONS: Conventional brain MRI is a common practice for prognostication after CA. Advanced imaging techniques are used infrequently. The lack of standardized clinical pathways and variability in reported practices support a need for higher-quality evidence regarding the indications, timing, and acquisition protocols of clinical MRI studies.

Pediatric Acute Stroke Protocols in the United States and Canada.

OBJECTIVE: To describe existing pediatric acute stroke protocols to better understand how pediatric centers might implement such pathways within the context of institution-specific structures. STUDY DESIGN: We administered an Internet-based survey of pediatric stroke specialists. The survey included questions about hospital demographics, child neurology and pediatric stroke demographics, acute stroke response, imaging, and hyperacute treatment. RESULTS: Forty-seven surveys were analyzed. Most respondents practiced at a large, freestanding children's hospital with a moderate-sized neurology department and at least 1 neurologist with expertise in pediatric stroke. Although there was variability in how the hospitals deployed stroke protocols, particularly in regard to staffing, the majority of institutions had an acute stroke pathway, and almost all included activation of a stroke alert page. Most institutions preferred magnetic resonance imaging (MRI) over computed tomography (CT) and used abbreviated MRI protocols for acute stroke imaging. Most institutions also had either CT-based or magnetic resonance-based perfusion imaging available. At least 1 patient was treated with intravenous tissue plasminogen activator (IV-tPA) or mechanical thrombectomy at the majority of institutions during the year before our survey. CONCLUSIONS: An acute stroke protocol is utilized in at least 41 pediatric centers in the US and Canada. Most acute stroke response teams are multidisciplinary, prefer abbreviated MRI over CT for diagnosis, and have experience providing IV-tPA and mechanical thrombectomy. Further studies are needed to standardize practices of pediatric acute stroke diagnosis and hyperacute management.

Variation in Treatment and Outcomes of Children With Acute Disseminated Encephalomyelitis.

OBJECTIVES: To characterize variation in treatments and outcomes of pediatric patients admitted to children's hospitals with acute disseminated encephalomyelitis (ADEM). METHODS: In this retrospective cohort study, we used data from the Pediatric Health Information System. Children >30 days old who were hospitalized from 2010 to 2015 with ADEM were included. Variables analyzed were treatments and admission to an ICU. Primary outcomes were discharge disposition and readmissions for relapses (ADEM readmissions) or for continued comorbidities (non-ADEM readmissions). RESULTS: A total of 954 patients with ADEM had 1117 admissions. Treatments included steroids (80%), immunoglobulin (22%), and plasmapheresis (6.6%); 15% of admissions included none of these treatments. Treatments varied by center (P < .001). Thirty-four percent of admissions included ICU admission, which was associated with an increased number and duration of treatments (P < .01). The discharge disposition was home in 85% of admissions; home with health services, rehab facility, or other in 13.6%; and mortality in 1.4%. Twelve percent (117 of 954) of patients had >1 admission for ADEM. Treatment choice and ICU stay were not associated with ADEM readmissions. Sixteen percent (181 of 1101) of ADEM admissions had a non-ADEM readmission within 90 days. Prolonged ICU hospitalization was associated with non-ADEM readmission (adjusted odds ratio 1.9; P = .017) and decreased likelihood of discharge from the hospital to home (adjusted odds ratio 0.1; P < .001). After adjusting for ICU duration, treatment choice and duration were not associated with non-ADEM readmission or hospital disposition. CONCLUSIONS: Significant variation in ADEM treatment exists across centers. Admission to an ICU for ADEM was associated with increased immunotherapy, additional health services at discharge, and readmission for diagnoses other than ADEM.

Non-invasive estimation of cerebral perfusion pressure using transcranial Doppler ultrasonography in children with severe traumatic brain injury.

OBJECTIVE: To identify if cerebral perfusion pressure (CPP) can be non-invasively estimated by either of two methods calculated using transcranial Doppler ultrasound (TCD) parameters. DESIGN: Retrospective review of previously prospectively gathered data. SETTING: Pediatric intensive care unit in a tertiary care referral hospital. PATIENTS: Twenty-three children with severe traumatic brain injury (TBI) and invasive intracranial pressure (ICP) monitoring in place. INTERVENTIONS: TCD evaluation of the middle cerebral arteries was performed daily. CPP at the time of the TCD examination was recorded. For method 1, estimated cerebral perfusion pressure (CPPe) was calculated as: CPPe = MAP × (diastolic flow (Vd)/mean flow (Vm)) + 14. For method 2, critical closing pressure (CrCP) was identified as the intercept point on the x-axis of the linear regression line of blood pressure and flow velocity parameters. CrCP/CPPe was then calculated as MAP-CrCP. MEASUREMENTS AND MAIN RESULTS: One hundred eight paired measurements were available. Using patient averaged data, correlation between CPP and CPPe was significant (r = 0.78, p = < 0.001). However, on Bland-Altman plots, bias was 3.7 mmHg with 95% limits of agreement of - 17 to + 25 for CPPe. Using patient averaged data, correlation between CPP and CrCP/CPPe was significant (r = 0.59, p = < 0.001), but again bias was high at 11 mmHg with wide 95% limits of agreement of - 15 to + 38 mmHg. CONCLUSIONS: CPPe and CrCP/CPPe do not have clinical value to estimate the absolute CPP in pediatric patients with TBI.

Pediatric Stroke Impairs Theory of Mind Performance.

AIM: This pilot study explored whether childhood stroke impairs performance on theory of mind (ToM) tasks and whether ToM task performance correlates with resting state connectivity in brain regions linked with social cognition. METHOD: We performed a case-control study of 10 children with stroke and 10 age- and gender-matched controls. They completed 2 ToM tasks, and resting state connectivity was measured with functional magnetic resonance imaging (MRI). RESULTS: Children with stroke performed worse than controls on conative ToM tasks. Resting state connectivity in the central executive network was significantly higher and connectivity between right and left inferior parietal lobules was significantly decreased in children with stroke. Resting state activity and ToM performance were not significantly correlated. INTERPRETATION: Childhood stroke results in poorer performance on specific ToM tasks. Stroke is associated with changes in resting state connectivity in networks linked with social cognition including ToM. Although the basis for these changes in connectivity is not well understood, these results may provide preliminary insights into potential mechanisms affecting social cognition after stroke. The findings suggest that further study of the effect of childhood stroke on network connectivity may yield insights as to how stroke affects cognitive functions in children.

Comparative study of posterior and anterior circulation stroke in childhood: Results from the International Pediatric Stroke Study.

OBJECTIVE: To compare risk factors, clinical presentation, and outcomes after posterior circulation arterial ischemic stroke (PCAIS) and anterior circulation arterial ischemic stroke (ACAIS) in neonates and children. METHODS: In this international multicenter observational study including neonates and children up to 18 years of age with arterial ischemic stroke (AIS), we compared clinical and radiologic features according to stroke location. RESULTS: Of 2,768 AIS cases, 507 (18%) were located in the posterior circulation, 1,931 (70%) in the anterior circulation, and 330 (12%) involved both. PCAIS was less frequent in neonates compared to children (8.8% vs 22%, p < 0.001). Children with PCAIS were older than children with ACAIS (median age 7.8 [interquartile range (IQR) 3.1-14] vs 5.1 [IQR 1.5-12] years, p < 0.001), and more often presented with headache (54% vs 32%, p < 0.001) and a lower Pediatric NIH Stroke Scale score (4 [IQR 2-8] vs 8 [IQR 3-13], p = 0.001). Cervicocephalic artery dissections (CCAD) were more frequent (20% vs 8.5%, p < 0.001), while cardioembolic strokes were less frequent (19% vs 32%, p < 0.001) in PCAIS. Case fatality rates were equal in both groups (2.9%). PCAIS survivors had a better outcome (normal neurologic examination at hospital discharge in 29% vs 21%, p = 0.002) than ACAIS survivors, although this trend was only observed in children and not in neonates. CONCLUSION: PCAIS is less common than ACAIS in both neonates and children. Children with PCAIS are older and have a higher rate of CCAD, lower clinical stroke severity, and better outcome than children with ACAIS.

Arterial Ischemic Stroke Secondary to Cardiac Disease in Neonates and Children.

OBJECTIVE: We describe the risk factors for peri-procedural and spontaneous arterial ischemic stroke (AIS) in children with cardiac disease. METHODS: We identified children with cardiac causes of AIS enrolled in the International Pediatric Stroke Study registry from January 2003 to July 2014. Isolated patent foramen ovale was excluded. Peri-procedural AIS (those occurring during or within 72 hours of cardiac surgery, cardiac catheterization, or mechanical circulatory support) and spontaneous AIS that occurred outside of these time periods were compared. RESULTS: We identified 672 patients with congenital or acquired cardiac disease as the primary risk factor for AIS. Among these, 177 patients (26%) had peri-procedural AIS and 495 patients (74%) had spontaneous AIS. Among non-neonates, spontaneous AIS occurred at older ages (median 4.2 years, interquartile range 0.97 to 12.4) compared with peri-procedural AIS (median 2.4 years, interquartile range 0.35 to 6.1, P < 0.001). About a third of patients in both groups had a systemic illness at the time of AIS. Patients who had spontaneous AIS were more likely to have a preceding thrombotic event (16 % versus 9 %, P = 0.02) and to have a moderate or severe neurological deficit at discharge (67% versus 33%, P = 0.01) compared to those with peri-procedural AIS. CONCLUSIONS: Children with cardiac disease are at risk for AIS at the time of cardiac procedures but also outside of the immediate 72 hours after procedures. Many have acute systemic illness or thrombotic event preceding AIS, suggesting that inflammatory or prothrombotic conditions could act as a stroke trigger in this susceptible population.

Characteristics and Outcome in Children With Craniectomy Following Acute Ischemic Stroke in the International Pediatric Stroke Study.

The outcome of children with acute ischemic stroke treated with craniectomy has not been thoroughly examined. In adults, hemicraniectomy after middle cerebral artery territory stroke and posterior decompression after posterior circulation stroke has been shown to improve outcome. Pediatric cases of hemicraniectomy for middle cerebral artery stroke and posterior decompression following posterior circulation stroke suggest relatively good outcome. There are no published data in adults or children with craniectomy after cerebral sinovenous thrombosis. Our aim was to determine the outcome of children with acute ischemic stroke treated with craniectomy in the International Pediatric Stroke Study (IPSS). We included children enrolled who had a craniectomy following stroke presentation. Of 4294 patients in IPSS, 38 children (1%) were found to have craniectomy following an ischemic stroke. Of 38 craniectomy cases, 29 had anterior circulation strokes, 5 had posterior circulation strokes, and 4 had cerebral sinovenous thromboses. The mortality rate was 8%. Overall, children who have craniectomies have significant neurologic deficits. Prospective studies are needed to examine long-term morbidity following craniectomy.

Intensive care resources required to care for critically ill children with focal intracranial infections.

The authors reviewed cases in which children with a focal infection inside the head (ex: a brain abscess) were cared for in their pediatric ICU to describe the frequency of complications and quantify the ICU resources needed (ex: breathing tube, blood pressure medications, and/or an intracranial pressure monitor). This information helps clarify illness severity and has identified complications that we should further investigate to improve care for these children.

Cerebral blood flow velocity and autoregulation in paediatric patients following a global hypoxic-ischaemic insult.

AIM: To describe the cerebral blood flow velocity pattern and investigate cerebral autoregulation using transcranial Doppler ultrasonography (TCD) following a global hypoxic-ischaemic (HI) event in children. METHODS: This was a prospective, observational study in a quaternary-level paediatric intensive care unit. Intubated children, newborn to 17 years admitted to the PICU following HI injury (asphyxia, drowning, cardiac arrest) were eligible for inclusion. TCD was performed daily until post-injury day 8, discharge, or death, whichever occurred earliest. RESULTS: Twenty-six patients were enrolled. Median age was 3 years (0.33, 11.75), initial pH 6.95, and initial lactate 5.4. Median post-resuscitation Glasgow Coma Score was 3T. Across the entire cohort, cerebral blood flow velocity (CBFV) was near normal on day 1. Flow velocity increased to a maximum median value of 1.4 standard deviations above normal on day 3 and slowly downtrended back to baseline by the end of the study period. Median Paediatric Extended Version of the Glasgow Outcome Score was 4 at three months. No patient in the favourable outcome group had extreme CBFV on day one, and only one patient in the favourable group had extreme CBFV on PID 2. In contrast, 38% of patients in the unfavourable group had extreme CBFV on PID 1 (p=.039 compared to frequency in favourable group), and 55% had extreme CBFV on PID 2 (p = .023 compared to frequency in favourable group). No patient had consistently intact cerebral autoregulation throughout the study period. CONCLUSIONS: Following a HI event, patients with favourable neurologic outcomes had flow velocity near normal whereas unfavourable outcomes had more extreme flow velocity. Intermittently intact cerebral autoregulation was more frequently seen in those with favourable neurologic outcomes though return to the autoregulatory baseline appears delayed.

Acanthamoeba granulomatous amoebic encephalitis after pediatric hematopoietic stem cell transplant.

Acanthamoeba encephalitis is a rare, often fatal condition, particularly after HSCT, with 9 reported cases to date in the world literature. Our case was originally diagnosed with ALL at age 3 years, and after several relapses underwent HSCT at age 9 years. At 17 years of age, he was diagnosed with secondary AML for which he underwent a second allogeneic HSCT. He presented with acute-onset worsening neurological deficits on day +226 after the second transplant and a post-mortem diagnosis of Acanthamoeba encephalitis was established, with the aid of the CDC.