Visual evoked potentials in intensive care

Potenciales evocados visuales en cuidados intensivos

The purpose of this work is to check whether the visual evoked potentials in patients hospitalized in the intensive care unit (ICU) and under sedation vary in their parameters of amplitude and latency, depending on whether they are performed with the eyes open or closed. Eight visual evoked potentials were performed in patients hospitalized in the ICU, with alteration of their state of consciousness by pharmacological sedation, without neurological compromise; according to the clinical history and the treatment pathologies were not of neurological origin. No differences were found in the parameters of amplitude and speed of conduction (latency) when performed with the eyes open and closed. However, attention is drawn to the improvement in the speed that oscillates around 1% and that although clinically does not alter the final result of normality if it represents an increase of 1.5 ms of nerve conduction when performed with closed eyes. Evoked potentials can continue to be performed without taking into account the position of the eyelids in patients under sedation in the ICU, thus being certain that the data obtained reflect the integrity of the visual pathway in subjects who, due to their state of consciousness, can not collaborate with other clinical data.

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