Cyprane 'Tec' Mk II vaporiser - Pentec
Date of manufacture:
This is a derivative of the Cyprane Fluotec Mk II that has been calibrated for Methoxyflurane 'Penthrane' (Abbott Laboratories). The dial is calibrated 0 - 1.5 %. It is a plenum vaporiser. This means that it has a significant flow resistance causing the vaporisation chamber to be at a higher pressure than the outlet pressure. This is a manufacturing convenience permitting an accurate and reproducible split to be achieved between through-vaporiser and bypass flows. The flow resistance of the mechanism is too high for it to be placed in the patient's airway. It's outflow is temperature compensated for changes in chamber temperature by means of a valve that is actuated by a bimetal strip mechanism. The Mark II series was launched with the 'Fluotec Mk II' for halothane. There were also 'Tritec' (trichloroethylene), 'Pentec' (methoxyflurane) vaporisers commercially marketed in the range. These vaporisers are mounted on the back bar of a conventional Boyle-type anaesthetic machine, forming part of the fresh gas manifold. The plastic card (just visible on left), chained to the device, carries calibration corrections for low flow use. An observation window reveals the level of the liquid anaesthetic. Note that there is no mechanism to prevent the vaporiser from being filled with the wrong liquid.