Biomedical subjects

I Morgado

Publications and source records attributed to I Morgado.

3 recordsLinked to original sources

PubMed2004

[Sedation with remifentanil for tracheostomy in a pediatric patient].

Remifentanil is an ultra-short-acting opioid that is frequently used in adults for surgical anesthesia or conscious sedation, but its use in children is much less common. We report the case of a 7-year-old boy with lateral cervical tumors displacing all cervical and facial structures. An emergency tracheostomy was performed when he developed respiratory difficulty due to partial airway obstruction. Because of the size and location of the intraoral tumors and a history of bleeding, orotracheal intubation and other airway management techniques were ruled out. The tracheostomy was performed under local anesthesia and sedation with a perfusion of 0.05 x microgKg(-1) x min(-1) provided the necessary relaxation and immobility for surgery. Sedation under observation with monitoring is among the indications of remifentanil. Spontaneous breathing is maintained with infusions less than 0.05 to 0.1 microg x Kg(-1) x min(-1). In the case we report, the patient's risk of complete airway obstruction due to bleeding upon manipulation had to be assessed and compared with the respiratory depression that might possibly have been caused by remifentanil perfusion. We judged that the option of sedation would cause less morbidity and offered greater safety for the patient. The outcome of this case is consistent with reports that remifentanil is a good option for adequately sedating children who are breathing spontaneously.

Airway Obstruction↗

PubMedDate not supplied

[The amigdaloid body: functional implications].

INTRODUCTION: The amygdaloid body is a structure localized to the temporal lobe in mammals, formed by different nuclei and traditionally associated with the emotion system of the brain. Some investigators have suggested an alternative function for the amygdaloid body, considering it to be part of the system modulating memory. Much of the experimental data supports both functions. DEVELOPMENT: The relation of the amygdaloid body with the emotions has been based on the study of the conditioning of fear, by which an emotionally neutral stimulus can cause emotional reactions due to its temporal association with an adverse stimulus. It has been shown that the amygdaloid body is necessary for learning and expressing this conditioning, and is therefore involved in emotional learning. With regard to the relation of the amygdaloid body with the modulation of memory, one should point out the results which show that it is not always necessary for learning and memory, but is necessary for showing the modulating effects of different substances on memory. The amygdaloid body modulates the storage of memory in other regions of the brain, such as the caudate nucleus and the hippocampus. CONCLUSIONS: Current data suggests that the whole amygdaloid complex is not involved in the two functions. However, the lateral and central nuclei participate in emotional learning whilst the basolateral nucleus is especially involved in modulation of the memory when emotional activation occurs.

Affect↗

PubMedDate not supplied

[The psychobiology of learning and memory: fundamentals and recent advances].

AIM: This review describes the concepts, temporal dynamics and main features of learning and memory systems from a comprehensive molecular, neuroanatomical, neurophysiological, cognitive and behavioural approach. DEVELOPMENT: Starting with molecular mechanisms of synaptic plasticity we describe the memory stages, implicit and explicit memory systems, working memory, remembering and forgetting. Each process is illustrated with examples of recent experimental and clinical research. CONCLUSIONS: Learning and memory are closely related brain processes which give rise to adaptive changes in behaviour. Implicit memory is a kind of unconscious and rigid memory for habits, which is based on brain regions processing perceptions and motor and emotional information, like the neocortex, the neostriatum, the cerebellum or the amygdala. Explicit or declarative memory is a conscious and flexible memory, hippocampus-dependent. Working memory is actually a system of executive cognition, based on interactions between the prefrontal cortex and other brain regions. The retrieval of complex memories consist of an active process of reconstruction of the past which incorporates new experiences of the subject who is remembering. The reactivation of memories can initiate genuine processes of reconsolidation and extinction. Forgetting could depend on alterations in the neural networks storing the information or, otherwise, on active processes which hinder consolidation or block the expression of the memories.

Animals↗