Article

Visual evaluation of fade in response to facial nerve stimulation at the eyelid

Department of Anesthesiology, Fukushima Medical University, Hukusima, Fukushima, Japan
Journal of Clinical Anesthesia (Impact Factor: 1.21). 06/2005; 17(4):276-80. DOI: 10.1016/j.jclinane.2004.08.009
Source: PubMed

ABSTRACT The aim of this study is to investigate the probability of visual detection of fade in response to train-of-four (TOF) stimulation, double-burst stimulation3,3 (DBS(3,3)), or DBS(3,2) at the eyelid in comparison to that at the thumb.
This is a randomized single-blinded study.
The study took place at the University hospital.
Sixty adult patients underwent general anesthesia.
Patients were randomly divided into either the eyelid group (n = 30) or the thumb group (n = 30). In the eyelid group, at the varying degrees of neuromuscular block caused by vecuronium, TOF, DBS(3,3), or DBS(3,2) were given at the temporal branch of the facial nerve, and the probability of visual detection of fade in response to TOF, DBS(3,3), or DBS(3,2) was determined at the eyelid. Similarly, in the thumb group, the probability of visual detection of fade in response to TOF, DBS(3,3), or DBS(3,2) was examined at the thumb.
When the true TOF ratios were 0 to 0.60, the probability of detection of TOF fade in the eyelid group was significantly lower than in the thumb group (P < .05). At the true TOF ratios of 0.31 to 0.70, the probability of visual detection of DBS(3,3) fade in the eyelid group was significantly less than in the thumb group (P < .05). When the true TOF ratios were 0.81 to 1.00, the probability of detection of DBS(3,2) fade in the eyelid group was significantly higher than in the thumb group (P < .05).
The probability of visual detection of fade in response to TOF or DBS(3,3) is lower at the eyelid than the thumb. In contrast, DBS(3,2) fade tends to be seen more frequently at the eyelid than at the thumb.

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