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Updated: Jan 31, 2026

A Novel Rescue Technique for Difficult Intubation and Difficult Ventilation
Published on: January 17, 2011
Respiratory rate is an inadequate parameter of ventilation in non-intubated sedation
Keiko Morimoto1, Shin Ogura2, Kenichiro Shinohara3
1Department of Dental Anesthesiology, The Nippon Dental University School of Life Dentistry at Tokyo, 1-9-20 Fujimi Chiyoda-ku, Tokyo, 102-8159, Japan. iamkeiko@tky.ndu.ac.jp.
Abstract:
We compared the respiratory rate (RR) and transcutaneous carbon dioxide pressure ([Formula: see text]) during intravenous sedation (IVS), to determine whether RR is a useful parameter for monitoring ventilation. This was a prospective cohort study. The study sample comprised dental patients who received IVS via propofol or midazolam administration at Nippon Dental University Hospital. We simultaneously measured RR (through capnography), [Formula: see text] (using the [Formula: see text] monitor), and percutaneous oxygen saturation (SpO2). RR was the predictor and the outcome variable was [Formula: see text]. Data were analyzed by Dunnett's test and Pearson's correlation coefficient. P < 0.05 was considered statistically significant. The study sample consisted of 15 patients. No significant changes were identified in the RR and SpO2 measurements over time. However, [Formula: see text] values obtained from 20 to 40 min after induction of sedation were significantly higher than baseline values (P < 0.05). A correlation was found between RR and [Formula: see text] (P < 0.05), but the correlation coefficient was low (r = 0.22), indicating a weak correlation between these two factors. The results of this study suggest that RR is an inadequate parameter for monitoring ventilation during IVS; however, [Formula: see text] may be useful for monitoring.
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