Effect of postictal process in motor deficit and monoaminergic concentration in hippocampus, cerebellum, and cortex / Efecto del proceso postictal en el déficit motor y la concentración monoaminérgica en el hipocampo, el cerebelo y la corteza

Abstract Introduction Systemic administration of pentylenetetrazole (PTZ) causes brain damage (BD), and triggers a series of morphological and neurochemical changes, which in turn bring about behavioral, cognitive, and motor deficits. Serotonin (5-HT), dopamine (DA), and noradrenaline (NA) levels are controlled by various brain structures and these levels are related to motor activity; however, the concentration of these neurotransmitters during the postictal process remains unknown. Objective We investigated the concentration of 5-HT, NA and DA in the hippocampus, cerebellum, and cortex on motor deficit during the postictal stage. Method Eighteen male Wistar rats (300 g) assigned to two groups: control (n = 9, saline solution) and experimental (n = 9, PTZ) were used. Myoclonic shakes were counted and motor behavior assessments were recorded during three hours post PTZ injection (90 mg/kg). The cortex, cerebellum, and hippocampus of each rat were dissected to determine the 5-HT, DA, and NA concentration by high performance liquid chromatography. Results PTZ induced a significant increase in total 5-HT and DA levels in the hippocampus and cortex; in the cerebellum there was a significant increase in the concentration of 5-HT and NA. The presence of myoclonic shakes as well as a marked motor deficit in the experimental group were significantly different in comparison to the control. Discussion and conclusion 5-HT modifies the concentration of other monoamines directly involved in motor aspects such as NA and DA in the hippocampus, cerebellum, and cortex during the postictal process.

Resumen Introducción La administración sistémica de pentilentetrazol (PTZ) causa daño cerebral y desencadena una serie de cambios morfológicos y neuroquímicos que a su vez provocan déficits conductuales, cognitivos y motores. Los niveles de serotonina (5-HT), dopamina (DA) y noradrenalina (NA) son modulados por varias estructuras cerebrales y sus concentraciones se relacionan con la actividad motora; sin embargo, se desconoce la concentración de estos neurotransmisores durante el proceso postictal. Objetivo Evaluar la manera en que la concentración de 5-HT, NA y DA en el hipocampo, el cerebelo y la corteza influye en el déficit motor durante la etapa postictal. Método Se utilizaron 18 ratas macho Wistar (300 g), divididas en dos grupos: control (n = 9, solución salina) y experimental (n = 9, PTZ). Se registraron las sacudidas mioclónicas y se evaluó el comportamiento motor durante tres horas después de la inyección de PTZ (90 mg/kg). Se extrajeron la corteza, el cerebelo y el hipocampo de cada rata para determinar la concentración de 5-HT, DA y NA mediante cromatografía líquida de alta resolución. Resultados La administración de PTZ indujo un aumento significativo en los niveles totales de 5-HT y DA en el hipocampo y la corteza; en el cerebelo hubo un aumento significativo en la concentración de 5-HT y NA. Se encontró una diferencia significativa entre el grupo experimental y control con respecto a las sacudidas mioclónicas; asimismo, los animales del grupo experimental mostraron un marcado déficit motor. Discusión y conclusión La 5-HT modula la concentración de otras monoaminas involucradas directamente en aspectos motores tal como NA y DA en el hipocampo, el cerebelo y la corteza durante el proceso postictal.

Intraoperative Motor-Evoked Potential Disappearance versus Amplitude-Decrement Alarm Criteria During Cervical Spinal Surgery: A Long-Term Prognosis

BACKGROUND AND PURPOSE: We studied the clinical significance of amplitude-reduction and disappearance alarm criteria for transcranial electric muscle motor-evoked potentials (MEPs) during cervical spinal surgery according to different lesion locations [intramedullary (IM) vs. nonintramedullary (NIM)] by evaluating the long-term postoperative motor status. METHODS: In total, 723 patients were retrospectively dichotomized into the IM and NIM groups. Each limb was analyzed respectively. One hundred and sixteen limbs from 30 patients with IM tumors and 2,761 limbs from 693 patients without IM tumors were enrolled. Postoperative motor deficits were assessed up to 6 months after surgery. RESULTS: At the end of surgery, 61 limbs (2.2%) in the NIM group and 14 limbs (12.1%) in the IM group showed MEP amplitudes that had decreased to below 50% of baseline, with 13 of the NIM limbs (21.3%) and 2 of the IM limbs (14.3%) showing MEP disappearance. Thirteen NIM limbs (0.5%) and 5 IM limbs (4.3%) showed postoperative motor deficits. The criterion for disappearance showed a lower sensitivity for the immediate motor deficit than did the criterion for amplitude decrement in both the IM and NIM groups. However, the disappearance criterion showed the same sensitivity as the 70%-decrement criterion in IM (100%) and NIM (83%) surgeries for the motor deficit at 6 months after surgery. Moreover, it has the highest specificity for the motor deficits among diverse alarm criteria, from 24 hours to 6 months after surgery, in both the IM and NIM groups. CONCLUSIONS: The MEP disappearance alarm criterion had a high specificity in predicting the long-term prognosis after cervical spinal surgery. However, because it can have a low sensitivity in predicting an immediate postoperative deficit, combining different MEP alarm criteria according to the aim of specific instances of cervical spinal surgery is likely to be useful in practical intraoperative monitoring.

Assessment of acute motor deficit in the pediatric emergency room / Avaliação do déficit motor agudo no ambiente de pronto socorro pediátrico

Abstract Objectives: This review article aimed to present a clinical approach, emphasizing the diagnostic investigation, to children and adolescents who present in the emergency room with acute-onset muscle weakness. Sources: A systematic search was performed in PubMed database during April and May 2017, using the following search terms in various combinations: "acute," "weakness," "motor deficit," "flaccid paralysis," "child," "pediatric," and "emergency". The articles chosen for this review were published over the past ten years, from 1997 through 2017. This study assessed the pediatric age range, from 0 to 18 years. Summary of the data: Acute motor deficit is a fairly common presentation in the pediatric emergency room. Patients may be categorized as having localized or diffuse motor impairment, and a precise description of clinical features is essential in order to allow a complete differential diagnosis. The two most common causes of acute flaccid paralysis in the pediatric emergency room are Guillain-Barré syndrome and transverse myelitis; notwithstanding, other etiologies should be considered, such as acute disseminated encephalomyelitis, infectious myelitis, myasthenia gravis, stroke, alternating hemiplegia of childhood, periodic paralyses, brainstem encephalitis, and functional muscle weakness. Algorithms for acute localized or diffuse weakness investigation in the emergency setting are also presented. Conclusions: The clinical skills to obtain a complete history and to perform a detailed physical examination are emphasized. An organized, logical, and stepwise diagnostic and therapeutic management is essential to eventually restore patient's well-being and full health.

Resumo Objetivos: Apresentar uma abordagem clínica, enfatizar a investigação diagnóstica, voltada para crianças e adolescentes no pronto-socorro com fraqueza muscular de surgimento agudo. Fontes: Foi feita uma pesquisa sistemática na base de dados PubMed entre abril e maio de 2017, com os seguintes termos de pesquisa em várias combinações: "agudo", "fraqueza", "déficit motor", "paralisia flácida", "criança", "pediátrico" e "emergência". Os trabalhos escolhidos para esta revisão foram publicados nos últimos dez anos, de 1997 a 2017. Este trabalho aborda a faixa etária pediátrica, até 18 anos. Resumo dos dados: O déficit motor agudo é uma causa razoavelmente comum para crianças e adolescentes procurarem o pronto-socorro. Os pacientes podem ser classificados como com deficiência motora localizada ou difusa e uma descrição precisa das características clínicas é essencial para possibilitar um diagnóstico diferenciado completo. As duas causas mais comuns de paralisia flácida aguda no pronto-socorro pediátrico são síndrome de Guillain-Barré e mielite transversa, independentemente de outras etiologias serem consideradas, como encefalomielite disseminada aguda, mielite infecciosa, miastenia grave, derrame, hemiplegia alternante da infância, paralisia periódica, encefalite do tronco encefálico e fraqueza muscular funcional. Os algoritmos da investigação de fraqueza aguda localizada ou difusa na configuração de emergência também são apresentados. Conclusões: São enfatizadas as habilidades clínicas para obter um histórico completo e fazer um exame físico detalhado. Um manejo diagnóstico e terapêutico organizado, lógico e por etapas é essencial para eventualmente restaurar o bem-estar e a saúde total do paciente.

Association of Initial Infarct Extent and Progressive Motor Deficits in Striatocapsular Infarction

BACKGROUND AND PURPOSE: Progression of motor deficits in the acute period is frequently observed in patients with subcortical striatocapsular infarctions. Therefore, we sought to determine the factors associated with early motor progression in patients with infarcts confined to the striatocapsular region. METHODS: We studied 80 consecutive patients with striatocapsular-region infarction, as defined by clinical and MRI criteria, within 24 hours after stroke onset. Motor progression was defined as an increase of >2 points in the motor items of the National Institutes of Health Stroke Scale (NIHSS) within 7 days of stroke onset. The study population was divided into patients with and without motor progression, and risk factors, clinical features, and brain MRI/magnetic resonance angiograpy (MRA) findings were compared between these groups. RESULTS: Motor progression was observed in 40% of the 80 patients. The independent variables associated with motor progression were a history of hypertension (OR=7.8, 95% CI=1.5-39.8, p=0.013) and an initial infarct extent of > or =15 mm (OR=9.2, 95% CI=1.8-45.7, p=0.006). However, there were no differences in the initial NIHSS score, other stroke risk factors, vascular stenosis pattern, or cardioembolic source. CONCLUSIONS: Early motor progression in patients with striatocapsular-region infarction is associated with the initial extent of the lesion. However, the stroke mechanism and vascular stenosis did not differ between the motor progression and stable groups.

Persistent Brachial Plexus Injury Associated with Axillary Brachial Plexus Block: A case report / 대한마취과학회지

A 26-year-old male patient presented for stump revision of an amputated right 3rd finger and neurorrhaphy for a lacerated right 2nd finger. An axillary brachial plexus block was performed using the transarterial technique. Postoperatively, the patient demonstrated signs and symptoms of brachial plexus injury. He exhibited paresthesia in the distribution of the ulnar nerve and motor weaknesses the wrist, elbow, and shoulder. On the 18th postoperative day, nerve conduction and electromyographic studies were performed, which revealed possible right radial neuropathy and axillary neuropathy, or right brachial plexopathy with posterior cord involvement. After seven months of medical and physical treatment, the pain subsided but slight paresthesia and muscle weaknesses still remained. We describe a case of postoperative neuropathy, which is believed to be caused by a direct nerve injury after an axillary brachial plexus block with persistent signs and symptoms over a considerable period.