Effects of inhalational anaesthesia with low tidal volume ventilation on end-tidal sevoflurane and carbon dioxide concentrations: prospective randomized study.

Autor: de la Matta-Martín M; Anesthesia Department, General Hospital, Hospital Universitario Virgen del Rocío, Sevilla, Spain. Electronic address: mdlmattam@hotmail.com., López-Herrera D; Anesthesia Department, General Hospital, Hospital Universitario Virgen del Rocío, Sevilla, Spain., Luis-Navarro JC; Anesthesia Department, General Hospital, Hospital Universitario Virgen del Rocío, Sevilla, Spain., López-Romero JL; Anesthesia Department, General Hospital, Hospital Universitario Virgen del Rocío, Sevilla, Spain.
Jazyk: angličtina
Zdroj: Revista espanola de anestesiologia y reanimacion [Rev Esp Anestesiol Reanim] 2014 Feb; Vol. 61 (2), pp. 78-86. Date of Electronic Publication: 2013 Dec 25.
DOI: 10.1016/j.redar.2013.06.007
Abstrakt: Objective: We investigated how ventilation with low tidal volumes affects the pharmacokinetics of sevoflurane uptake during the first minutes of inhaled anaesthesia.
Methods: Forty-eight patients scheduled for lung resection were randomly assigned to three groups. Patients in group 1, 2 and 3 received 3% sevoflurane for 3 min via face mask and controlled ventilation with a tidal volume of 2.2, 8 and 12 ml kg(-1), respectively (Phase 1). After tracheal intubation (Phase 2), 3% sevoflurane was supplied for 2 min using a tidal volume of 8 ml kg(-1) (Phase 3).
Results: End-tidal sevoflurane concentrations were significantly higher in group 1 at the end of phase 1 and lower at the end of phase 2 than in the other groups as follows: median of 2.5%, 2.2% and 2.3% in phase 1 for groups 1, 2 and 3, respectively (P<0.001); and 1.7%, 2.1% and 2.0% in phase 2, respectively (P<0.001). End-tidal carbon dioxide values in group 1 were significantly lower at the end of phase 1 and higher at the end of phase 2 than in the other groups as follows: median of 16.5, 31 and 29.5 mm Hg in phase 1 for groups 1, 2 and 3, respectively (P<0.001); and 46.2, 36 and 33.5 mm Hg in phase 2, respectively (P<0.001).
Conclusion: When sevoflurane is administered with tidal volume approximating the airway dead space volume, end-tidal sevoflurane and end-tidal carbon dioxide may not correctly reflect the concentration of these gases in the alveoli, leading to misinterpretation of expired gas data.
(Copyright © 2013 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Published by Elsevier España. All rights reserved.)
Databáze: MEDLINE