Nitrous Oxide Sedation and Bispectral Index

ABSTRACT

Objectives: To determine whether bispectral analysis (BIS) changes during nitrous oxide (N2O) sedation in anxious children undergoing extraction of primary teeth.

Methods: In this prospective study 45, ASA physical status I children, aged between 7 to 12 years and scheduled for primary teeth extraction under N2O/O2 sedation are included. At baseline (T0) and during the sedation procedure (T1-6); BIS levels, Ramsay Sedation Scores (RSS), oxygen saturation (Sp02), and heart rate (HR) were recorded at one-minute intervals. Forty percent N2O in O2 was given by a nasal hood, and N2O concentration was enhanced to 60% in a two-minute period. Paired measurements of BIS levels with Observer’s Assessment of Alertness and Sedation (OAA/S) scores were obtained during sedation procedure

Results: Since 5 patients refused application of the nasal hood, a total 40 of the original 45 subjects completed the study. Mean age and weight of the children were 9.5 ± 1.4 years and 23.7 ± 9.7 kg, respectively. Nitrous oxide inhalation produced no changes in BIS levels despite a sedation level in OAA/S scores were observed at 40-60% N2O concentrations

Conclusions:BIS values do not change during N2O/O2 sedation and the BIS monitor is not appropriate to evaluate the depth of sedation provided by N2O/O2 during primary teeth extraction in children. (Eur J Dent 2007;1:240-245)

Key words

Nitrous oxide sedation - Bispectral index - Anxiety - Ramsay sedation scale

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