British journal of anaesthesia
-
Estimation of teeth-to-vallecula distance would facilitate the selection of properly sized oropharyngeal airways in young children. The aims of the present study were to measure the teeth-to-vallecula distance and to create an algorithm to predict this distance based on anatomical landmarks and patient characteristics in children. ⋯ The teeth-to-vallecula distance can be predicted using the age and the mouth-to-mandible distance in young children.
-
There is a need for a bedside functional residual capacity (FRC) measurement method that performs well in intensive care patients during many modes of ventilation including controlled, assisted, spontaneous, and mixed. We developed a modified multiple breath nitrogen washout method for FRC measurement that relies on end-tidal gas fractions and alveolar tidal volume measurements as inputs but does not require the traditional measurements of volume of nitrogen or oxygen. Using end-tidal measurements, not volume, reduces errors from signal synchronization. This study was designed to assess the accuracy, precision, and repeatability of the proposed FRC system in subjects with variable ventilation patterns including some spontaneous effort. ⋯ The modified multiple breath nitrogen washout method for FRC measurement provides improved precision and equivalent accuracy and repeatability compared with existing methods during ventilation with variable ventilation patterns. Further study of the novel N₂ washout method is needed.