The Venturi Anaesthesia Circuit II Carbon Dioxide Production and Gas Flow Requirements

Abstract
CO2 production was measured in 20 adult patients undergoing alloplastic operation of the hip. Body weight ranged from 40-81 kg. Anesthesia consisted of lumbar plexus block, i.v., diazepam, pethidine, pavulon and N2O/O2 under controlled ventilation. CO2 production was 2.13 ml kg-1 min-1 (interquartile range 2.09-2.23). A fresh gas flow rate of .apprx. 30 ml kg-1 min-1 was required for the elimination of CO2 produced when using the Venturi system for inhalation anesthesia.