Resistance to gas flow in heat and moisture exchangers

Heat and moisture exchangers in artificial ventilation. An experimental study of the effect of gas leakage.

The effect of gas leakage around an uncuffed tracheal tube on the performance of Heat and Moisture Exchangers (HME) was examined experimentally. Such leaks were shown to cause measurable decreases in the humidity output and efficiency of HME. The magnitude of the decrease in humidity output was shown to be dependent upon the proportion of expired volume which was leaked, and on the inspired vol...

Heat Transfer to Separation Flow in Heat Exchangers

Evaluation of resistance in 8 different heat-and-moisture exchangers: effects of saturation and flow rate/profile.

INTRODUCTION When endotracheal intubation is required during ventilatory support, the physiologic mechanisms of heating and humidifying the inspired air related to the upper airways are bypassed. The task of conditioning the air can be partially accomplished by heat-and-moisture exchangers (HMEs). OBJECTIVES To evaluate and compare with respect to imposed resistance, different types/models of...

Efficiency of airway heat and moisture exchangers in anesthetized humans.

The efficiencies of airway heat and moisture exchanging filters in reducing respiratory water losses and increasing airway temperatures during general anesthesia were studied in five tracheally intubated patients given isoflurane, nitrous oxide, and oxygen anesthesia during controlled ventilation. Filters (Humid-Vent Filter, Humid-Vent 1, Pall Conserve, Siemens 150, and ThermoVent 600) were pla...

Heat-moisture exchangers and risk of nosocomial pneumonia.

ICU, 14% [before patient contact] and 25% [after patient con-tact]; cardiac surgery ICU, 6% [before] and 13% [after]). Observations in the medical ICU after introduction of the new, increasingly accessible, alcohol-based, waterless hand antiseptic revealed significantly higher handwashing rates (F<.05). Handwashing compliance improved as accessibility was enhanced: before patient contact, 19%, ...