Anesthesiology
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A device using modification of a Pitot tube has been designed for measurement of tidal volume in infants and small children. Its accuracy was compared both n vitro and n vivo to that of a calibrated pneumotachograph (Fleish #1) designed for a similar flow range. In vitro measurement of air flow with the modified Pitot tube (MPT) was within 5% of the pneumotachograph readings over a range of 1-60 l/min. ⋯ In vivo, the insertion of the MPT into the patient circuit caused no apparent changes in ventilatory parameters in children under 20 kg. Measurement of tidal volumes with the MPT agreed to within 8% of pneumotachograph readings. The low dead space (1.5 cc) and light weight (12 gm) of the MPT confer advantages over the pneumotachograph (15 ml dead space and a weight of 90 gm) for routine use in pediatric anesthesia.
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A new laryngoscope blade has been designed for emergency visualization of the pharynx and larynx when the pharyngeal space is restricted. The blade incorporates a 7-cm tube in the distal portion and an intraluminal light source protected from obstruction. It attaches to standard battery-powered light handles, making it practical for emergency use. The new blade has been tested on dogs and used successfully in 12 patients with edematous pharynges and in one patient with a bleeding pharyngeal tumor, where standard non-tubular blades failed to produce a view of the larynx.