Spontaneous respiration with the bain breathing circuit

Rebreathing and end-tidal CO2 during spontaneous breathing with the Bain circuit

“…Ten minutes after the injection the '~E was 55 • 30 ml.kg -1 "min -~ at an fof 16 -4 per minute; the FETco ~ was 6.4 • 0.9 per cent and the F1co ~ 0.7 Recordings are from the same patient during light N20-halothane anaesthesia before (upper part) and after alphaprodine (lower part). The maximum value in the trachea represents FBTcoz, the minimum F~or The CO7 concentration in the breathing tubes were sampled at 30 cm intervals from the point of fresh gas inflow (0) to the connector with the anaesthetic machine (6). End represents the per cent COz at the venting valve.…”

“…Strong recommendations were made that rebreathing must be avoided by using much higher fresh gas volumes (#F) than the suggested 100 ml/kg-~/min -~ . 6 An attempt to express the inspired CO2 concentration (Flco) as a C02 load was recently presented by Byrick; 7"8 this was based on the commonly held assumption that the patient is responding to the re-inhaled C02 with hyperventilation, thus compensating for the load imposed by the inhaled CO2. An inability to achieve such compensation, c.g., due to anaesthetic depression of respiration, would then cause hypercapnia.…”

Impact of Gas Delivery Systems on Imaging Studies of Human Cerebral Blood Flow

“…The ideal gas delivery circuit for controlling the oxygen alveolar concentration in an MRI scanner would be a closed Bain circuit in an intubated patent [23]. This obviously is not feasible for most research MRI scans and a compromise between optimum gas delivery and participant comfort must be found.…”

The use of the bain circuit in spontaneously breathing paediatric patients

“…8 Care should always be taken to verify the integrity of the circuit before its use. Cases of severe hypercapnia have been reported 9"t~ due to improper connection of the circuit.…”