Respiratory mechanics with constant flow inspiration. A comparison of two measurement techniques.

Resperatory compliance and resistance were measured during positive pressure ventilation in anaesthtized, paralysed dogs. Airway pressures measured during constant-flow inspiration allowed the calculation of pulmonary and chest-wall resistances, and static and non-static compliances. Contiguous studies of dynamic compliance and resistance allowed comparison of the two techniques, and the level of agreement was reasonalble. Cconstant-flow inflation of the lungs allows a simple means of measuring respiratory mechanics, and should be valid for the observation of short-term changes in the apnoeic patient.