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ObjectiveThis study was conducted to reassess the concepts established over the past 20 years, in particular in the last 5 years, about the use of methylene blue in the treatment of vasoplegic syndrome in cardiac surgery.MethodsA wide literature review was carried out using the data extracted from: MEDLINE, SCOPUS and ISI WEB OF SCIENCE.ResultsThe reassessed and reaffirmed concepts were 1) MB is safe in the recommended doses (the lethal dose is 40 mg/kg); 2) MB does not cause endothelial dysfunction; 3) The MB effect appears in cases of NO up-regulation; 4) MB is not a vasoconstrictor, by blocking the cGMP pathway it releases the cAMP pathway, facilitating the norepinephrine vasoconstrictor effect; 5) The most used dosage is 2 mg/kg as IV bolus, followed by the same continuous infusion because plasma concentrations sharply decrease in the first 40 minutes; and 6) There is a possible "window of opportunity" for MB's effectiveness. In the last five years, major challenges were: 1) Observations about side effects; 2) The need for prophylactic and therapeutic guidelines, and; 3) The need for the establishment of the MB therapeutic window in humans.ConclusionMB action to treat vasoplegic syndrome is time-dependent. Therefore, the great challenge is the need, for the establishment the MB therapeutic window in humans. This would be the first step towards a systematic guideline to be followed by possible multicenter studies.

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Infusion of dexmedetomidine without bolus seems to be an effective adjuvant to fentanyl on the promotion of sedation and control of hemodynamic responses during surgery for congenital cardiopathies in children.

The postictal state is generally followed by antinociception. It is known that connections between the dorsal raphe nucleus, the periaqueductal gray matter, and the locus coeruleus, an important noradrenergic brainstem nucleus, are involved in the descending control of ascending nociceptive pathways. The aim of the present study was to determine whether noradrenergic mechanisms in the locus coeruleus are involved in postictal antinociception. Yohimbine (an α(2)-receptor antagonist) or propranolol (a β-receptor antagonist) was microinjected unilaterally into the locus coeruleus, followed by intraperitoneal administration of pentylenetetrazole (PTZ), a noncompetitive antagonist that blocks GABA-mediated Cl(-) influx. Although the administration of both yohimbine and propranolol to the locus coeruleus/subcoeruleus area resulted in a significant decrease in tonic or tonic-clonic seizure-induced antinociception, the effect of yohimbine restricted to the locus coeruleus was more distinct compared with that of propranolol, possibly because of the presynaptic localization of α(2)-noradrenergic receptors in locus coeruleus neurons. These effects were related to the modulation of noradrenergic activity in the locus coeruleus. Interestingly, microinjections of noradrenaline into the locus coeruleus also decrease the postictal antinociception. The present results suggest that the mechanism underlying postictal antinociception involves both α(2)- and β-noradrenergic receptors in the locus coeruleus, although the action of noradrenaline on these receptors causes a paradoxical effect, depending on the nature of the local neurotransmission.

Objetivo. Avaliar a eficácia do tratamento fisioterapêutico no tocan­te à qualidade de vida (QV), fadiga, independência funcional para realização de atividades de vida diária (AVDs), amplitude de movi­mento (ADM), força muscular, equilíbrio e marcha em pacientes com esclerose múltipla (EM). Método. Estudo longitudinal descriti­vo quantitativo desenvolvido com 4 indivíduos do gênero feminino, com faixa etária de 33 a 53 anos, realizado em domicílio uma vez por semana, por um período de 60 minutos, totalizando 30 sessões para cada paciente. A Escala de Determinação Funcional da Qualidade de Vida na esclerose múltipla (DEFU), Escala Modificada do Impacto da Fadiga (MFIS), Índice de Barthel, Goniometria, Teste Manual Mus­cular (TMM), Equiscala, e a Avaliação Cinemática da Marcha foram aplicadas em três avaliações (sessões 0, 15 e 30). Os testes de Fried­man e de Dunn através do programa de software “Graphpad InStat” foram utilizados como análise estatística. Resultados. Houve melhora na ADM, força muscular, equilíbrio e marcha após as 30 sessões, po­rém sem resultados significativos na avaliação da décima quinta sessão. Conclusão. As técnicas de facilitação neuromuscular proprioceptiva e os exercícios de Frenkel são eficazes no tratamento das pacientes com EM, sendo necessário um maior tempo de intervenção para melhores resultados.

Background. The purpose of this study was to access the effects of dexmedetomidine-fentanyl infusion on blood pressure (BP) and heart rate (HR) before surgical stimulation, on their changes to skin incision, and on isoflurane requirement during cardiac surgery in children. Methods. This study had a prospective, randomized, and open-label design. Thirty-two children aged 1 month to 10 years undergoing surgery for repair congenital heart disease (CHD) with CPB were randomly allocated into two groups: group MDZ received midazolam 0.2 mg·kg−1·h−1 and group DEX received dexmedetomidine 1 μg·kg−1·h−1 during the first hour followed by half of these rates of infusions thereafter. Both group received fentanyl 10 μg·kg−1, midazolam 0.2 mg·kg−1 and vecuronium 0.2 mg·kg−1 for induction. These same doses of fentanyl and vecuronium were infused during the first hour then reduced to half. The infusions started after induction and maintained until the end of surgery. Isoflurane was given briefly to control hyperdynamic response to skin incision and sternotomy. Results. In both groups, systolic blood pressure (sBP) and heart rate (HR) decreased significantly after one hour of infusion of the anesthetic solutions, but there were significantly less increase in diastolic blood pressure, sBP, and HR, and less patients required isoflurane supplementation to skin incision in the patients of the DEX group. Discussion. Dexmedetomidine infusion without a bolus appears to be an effective adjunct to fentanyl anesthesia in control of hemodynamic responses to surgery for repair of CHD in children.