Rodolfo Augusto Alves Pedrão
associations of sleep parameters measured by this index with the Richards-Campbell Sleep Questionnaire and environmental
noise.
Methods: This was a cross-sectional observational study that evaluated critically ill adults with diseases of low or moderate
severity. The following were measured: total sleep volume and time, deep sleep volume and time, continuous sleep volume
and time, sleep onset latency, and environmental sound pressure level. The subjective perception of sleep was evaluated with
the Richards-Campbell Sleep Questionnaire the morning after each night of observation.
Results: Patients had a low total sleep time (234 minutes), a predominance of superficial sleep stages, and little deep sleep
(1.7 minutes). The total, deep, and continuous sleep volumes were 3,679, 9.4, and 3,143 (bispectral index units × minutes),
respectively. The sleep latency was 94 minutes. The mean score of the Richards-Campbell Sleep Questionnaire was 57.9.
Total sleep volume, total sleep time, and continuous sleep volume were weakly correlated with the Richards-Campbell Sleep
Questionnaire depth of sleep domain score, overall sleep quality domain score, and total score. Total volume, total time, and
continuous volume were moderately correlated with the occurrence of awakenings domain score.
Conclusion: The bispectral index is an instrument with limited viability to monitor the sleep of lucid patients and patients
with low to moderate disease severity in the intensive care unit. Patients with higher total sleep volume, total sleep time, and
continuous sleep volume had better overall sleep perception.
