How to perform and interpret a middle cerebral artery transcranial Doppler examination in children at risk of brain injury

Transcranial Doppler (TCD) ultrasound is a non-invasive neuromonitoring technique that falls under the umbrella of point-of-care ultrasound. In this article, we provide a primer to encourage clinicians to perform TCD examinations and to aid them with accurately interpreting the scans. We focus on the middle cerebral artery waveforms and use traumatic brain injury as a model for brain insult.

Is ketamine infusion effective and safe as an adjuvant of sedation in the PICU? Results from the Ketamine Infusion Sedation Study (KISS)

STUDY OBJECTIVE

We aimed to evaluate the efficacy and safety of ketamine in ensuring comfort and sparing conventional drugs when used as an adjuvant for analgesia and sedation in the Pediatric Intensive Care Unit (PICU) as a continuous infusion (≥12 h).

DESIGN

Observational prospective study.

SETTING

Tertiary-care-center PICU.

PATIENTS

All consecutive patients <18 years who received ketamine for ≥12 h between January 2019 and July 2021.

INTERVENTIONS

ketamine infusion for ≥12 h.

MEASUREMENTS AND MAIN RESULTS

Seventy-seven patients (median age 16 months, Interquartile Range (IQR) 7-43) were enrolled. Twenty-six percent of patients (n = 20) were paralyzed, while 74% (n = 57) were not. The median infusion duration was 90 h (IQR 39-193), with doses between 15 (IQR 15-20) and 30 μg/kg/min (IQR 20-50). At 24 h of ketamine infusion, values of COMFORT-B-Scale (CBS) were significantly lower compared with values pre-ketamine (p < 0.001). Simultaneously, doses/kg/h of opioids and benzodiazepines significantly decreased at 24 h (p < 0.001 and p = 0.002, respectively), while doses/kg/h of propofol (p = 0.500) and dexmedetomidine (p = 0.072) did not significantly change. Seventy-four percent of non-paralyzed patients (42/57) had a decrease in CBS ≥2 points with no increase of concomitant analgosedation drugs. Among paralyzed patients (n = 20), 13 (65%) had no increase of concomitant analgosedation within 24 h after ketamine initiation. Overall, 55/77 (71%) of patients responded to ketamine. The mean and maximum ketamine infusion dosages were significantly higher in the non-responders (p = 0.021 and 0.028, respectively). Eleven patients had adverse events potentially related to ketamine (hypersalivation, systemic hypertension, dystonia/dyskinesia, tachycardia, and agitation) and six patients required intervention (dose reduction, suspension, or pharmacologic therapy). None of the patients developed delirium during ketamine infusion.

CONCLUSIONS

Ketamine used as a continuous infusion in the PICU might represent a valid strategy to ensure comfort and spare opioids and benzodiazepines in difficult-to-sedate PICU patients. Adverse events are minor and easily reversible. Future study will be needed to investigate long-term outcomes.

Corrigendum on: Ventilation weaning and extubation readiness in children in pediatric intensive care unit: A review

[This corrects the article DOI: 10.3389/fped.2022.867739.].

Evidence for inflammasome activation in the brain of mucopolysaccharidosis type II mice

Hunter syndrome or mucopolysaccharidosis type II (MPS II) is an X-linked recessive disease caused by the deficiency of iduronate 2-sulfatase (IDS), leading to storage of undegraded heparan and dermatan sulfate. Patients with the severe form present neurological abnormalities, but the mechanisms of such alterations are unknown. Here, we hypothesized that the undegraded substances found in this disease could be recognized as damage-associated molecular patterns (DAMPS), leading to activation of the inflammasome. Brains from 2 and 5 months normal and MPS II mice were studied. We observed an increase in cathepsin B activity in the brain tissue and leakage of this enzyme from the lysosome to the cytoplasm in a MPS II neuronal cell line, which is a known activator of the inflammasome. Furthermore, Caspase-1 activity and IL-1-beta levels were elevated at 5 months, confirming that this pathway is indeed altered. Our results suggest that undegraded GAG activate the inflammasome pathway in MPS II and future studies could focus on blocking such pathway to better understand the role of this process to the pathogenesis of MPS II.

Characteristics of Acute Nystagmus in the Pediatric Emergency Department

OBJECTIVES

Acute nystagmus (AN) is an uncommon neurologic sign in children presenting to pediatric emergency departments. We described the epidemiology, clinical features, and underlying causes of AN in a large cohort of children, aiming at identifying features associated with higher risk of severe underlying urgent conditions (UCs).

METHODS

Clinical records of all patients aged 0 to 18 years presenting for AN to the pediatric emergency departments of 9 Italian hospitals in an 8-year period were retrospectively reviewed. Clinical and demographic features and the underlying causes were analyzed. A logistic regression model was applied to detect predictive variables associated with a higher risk of UCs.

RESULTS

A total of 206 patients with AN were included (male-to-female ratio: 1.01; mean age: 8 years 11 months). The most frequently associated symptoms were headache (43.2%) and vertigo (42.2%). Ataxia (17.5%) and strabismus (13.1%) were the most common neurologic signs. Migraine (25.7%) and vestibular disorders (14.1%) were the most common causes of AN. Idiopathic infantile nystagmus was the most common cause in infants <1 year of age. UCs accounted for 18.9% of all cases, mostly represented by brain tumors (8.3%). Accordant with the logistic model, cranial nerve deficits, ataxia, or strabismus were strongly associated with an underlying UC. Presence of vertigo or attribution of a nonurgent triage code was associated with a reduced risk of UCs.

CONCLUSIONS

AN should be considered an alarming finding in children given the risk of severe UCs. Cranial nerve palsy, ataxia, and strabismus should be considered red flags during the assessment of a child with AN.

Bacterial meningitis in febrile young infants acutely assessed for presumed urinary tract infection: a systematic review

Urinary tract infections, the most common severe bacterial infections in young infants, may be associated with co-existing meningitis. There is no consensus on when to perform a lumbar puncture in these infants. Our aim was to quantify the frequency of co-existing bacterial meningitis in febrile young infants acutely assessed for presumed urinary tract infections. We systematically reviewed PubMed, EMBASE, and the Cochrane Library for studies including infants ≤ 3 months with suspected/confirmed urinary tract infections, who underwent a lumbar puncture. Two investigators independently reviewed articles for inclusion and extracted relevant data. Our outcomes were culture-confirmed meningitis and identification of low-/high-risk criteria of meningitis. Overall 20/2079 studies, including 4191 infants, met inclusion criteria. A total of 11 infants had bacterial meningitis (frequency between 0 and 2.1% across studies) and were mostly neonates. Of 253 infants meeting the low-risk criteria (well-appearing, age > 21 days, procalcitonin ≤ 0.5 ng/ml, and C reactive protein ≤ 20 mg/L) none developed meningitis, but only 15 underwent lumbar puncture.Conclusion: Co-existing bacterial meningitis in febrile young infants with urinary tract infection is rare. In those meeting low-risk criteria, a lumbar puncture may not be indicated. A case by case assessment should be made in infants not meeting low-risk criteria.Trial registration: CRD42018105339 What is known: • When caring for febrile infants ≤ 3 months with urinary tract infections, clinicians may have uncertainty on whether to perform a lumbar puncture (LP) for possible co-existing meningitis What is new: • An up-to-date systematic review of 20 studies found the frequency of co-existing meningitis in this population to be between 0 and 2.1% • Despite limited data, an LP may not be indicated in infants meeting low-risk criteria (being well-appearing, age > 21 days, procalcitonin ≤ 0.5 ng/ml, C reactive protein ≤ 20 mg/L). Ill-appearance and neonatal age appear to be significant risk factors of co-existing meningitis.

Risk factors and survival outcomes in patients with brain metastases from breast cancer

Development of central nervous system (CNS) metastases in breast cancer (BC) is associated with poor prognosis. The incidence of CNS metastases in metastatic BC is reported to be about 10-16 %, but different subtypes of BC are associated with different risk of developing CNS metastases. We retrospectively analysed the risk of CNS metastases and the outcome in a cohort of 473 patients with metastatic BC. CNS metastases were diagnosed in 15.6 % of patients and median survival from diagnosis of CNS metastases was 7.53 (25th-75th 2.8-18.9) months. The risk of developing CNS metastases was higher in patients with grade 3, hormone receptor negative, HER2-positive, high Ki-67 BC. When compared to luminal A subtype, only HER2-positive BC was associated with increased risk of CNS metastases. Survival from diagnosis of CNS metastases was longer in patients with HER2-positive BC, while it was shorter in patients that did not receive any locoregional treatment, or with extra-CNS disease, or with more than 3 CNS lesions.

Hemangiopericytoma of the Skull Base and Collet-Sicard Syndrome: A Case Report

Hemangiopericytoma (HP) is a mesenchymal tumor that originates from the pericytes of the capillary walls. This is a rare neoplasm, particularly in the head and neck; the skull base is involved exceptionally.

We report a case of a large HP located in the jugular foramen. The last four cranial nerves were involved, causing a Collet-Sicard syndrome associated with facial palsy. Only one case of HP and Collet-Sicard syndrome is reported in the literature. The clinical course of the disease is described, emphasizing the long period of elapsed time between onset of the complaints and the final diagnosis.

Diagnostic procedures and immunohistochemical evaluation are analyzed, along with the possible differential diagnosis with other pathological processes that more frequently involve the jugular foramen.

Hemangiopericytoma of the skull base and Collet-Sicard syndrome: a case report

Hemangiopericytoma (HP) is a mesenchymal tumor that originates from the pericytes of the capillary walls. This is a rare neoplasm, particularly in the head and neck; the skull base is involved exceptionally. We report a case of a large HP located in the jugular foramen. The last four cranial nerves were involved, causing a Collet-Sicard syndrome associated with facial palsy. Only one case of HP and Collet-Sicard syndrome is reported in the literature. The clinical course of the disease is described, emphasizing the long period of elapsed time between onset of the complaints and the final diagnosis. Diagnostic procedures and immunohistochemical evaluation are analyzed, along with the possible differential diagnosis with other pathological processes that more frequently involve the jugular foramen.

[Idiopathic cupulolithiasis: vasomotor reactivity evaluation of the vertebro-basilar artery by transcranial doppler ultrasonography and acetazolamide test]

Benign paroxysmal positional vertigo (BPPV) or cupulolithiasis is one of the more common peripheral vestibular disorders. Diagnosis is made on the observation of typical positioning nystagmus brought about by the Hallpike manoeuver. In most cases of BPPV, etiology is unknown. Microcirculatory disorders have often been considered responsible for idiopathic BPPV. Few reports have been published on this specific aspect of the problem. In our study we evaluated vertebro-basilar haemodynamics and vasomotory reactivity after Acetazolamide administration in 12 patients with idiopathic BPPV. The results obtained reveal the absence of macrocirculatory impairment in the vertebro-basilar district in basal conditions, but significative vasoreactivity variation after acetazolamide, both in vertebral and basilar arteries. Poor vasomotor reactivity in one vertebral artery was observed in 5 patients and, in two cases, in the basilar artery. Altered vasoreactivity in the middle cerebral arteries was not observed in any case. In the light of these findings, we suggest that a possible inadequate response if microcirculation in the labyrinth, in some particular haemodynamic situations, might cause otolithic damage.

Menière's disease in congenital nephrogenic diabetes insipidus: report of two twins

Two cases, twins, affected by congenital nephrogenic diabetes insipidus (CNDI) with a high daily volume of dilute urine excretion and periods of compensatory high levels of antidiuretic hormone (ADH) simultaneously developed a fluctuating Menière-type hearing loss. It is well known that the kidney and the cochlea are linked by structural and anatomic characteristics, as well as by the physiologic mechanism of electrolytes and fluid regulation. The patients herein described seem to be paradoxical, because they suffered from hydropic hearing loss despite the pathophysiologic mechanism of CNDI and the possible role played by ADH in water regulation in the inner ear. The consequences on Menière's disease of the different therapeutic regimens followed by the two CNDI patients are discussed. To our knowledge these are the first cases of CNDI with Menière's disease described in the literature.