Method for measuring adult-type pulmonary function tests in sedated infants and apparatus therefor

An apparatus for performing a maximum forced expiration maneuver in infants comprising

• control means,
• inflation means, responsive to said control means, for inflating the lungs of an infant with air to a volume greater than that reached at end-tidal inspiration in said infant's natural respiration,
• means for sensing a rate of airflow of said infant's respiration and sending a flow rate signal representative of said rate of airflow to said control means,
• means for sensing the pressure of said air inflating the lungs of said infant and sending an inflation pressure signal representative of said inflation pressure to said control means,
• compression means, responsive to said control means, for compressing the lungs of said infant,
• said control means being responsive to said flow rate signal and said inflation pressure signal whereby said control means
• 1. ) commands said inflation means to inflate said lungs of said infant synchronously with said infant's natural inspiration,
• 2.) detects a pause in said infant's natural respiration,
• 3.) thereupon commands said inflation means to inflate said infant's lungs to substantially total lung volume, and
• 4.) commands said compression means to compress said infant's lungs to substantially residual volume.

An apparatus for performing a maximum forced expiration an infant comprising

• a) a source of breathable air at superatmospheric pressure,
• b) an air distribution manifold in fluid communication with said source of air,
• c) a pneumotachograph in fluid communication with said manifold,
• d) a face mask in fluid communication with said pneumotachograph,
• e) an exhaust port in fluid communication with said manifold,
• f) an exhaust valve capable of opening and closing said exhaust port under command of a controller,
• g) a mouth air pressure sensor in fluid communication with said face mask,
• h) a pressure limit valve in fluid communication with said manifold,
• i) an inflatable vest for said infant,
• j) a source of pressurized gas,
• k) a pressurized gas conduit in fluid communication with said source of pressurized gas and said inflatable vest,
• l) a two-position vest inflation valve in said pressurized gas conduit capable of, in a first position, connecting said vest to said source of pressurized gas and, in a second position, connecting said vest to a vest exhaust port,
• m) a vest pressure sensor in fluid communication with said inflatable vest,
• n) an electronic controller capable of receiving signals from said pneumotachograph, said mouth pressure sensor and said vest pressure sensor
• 1. ) commanding said inflation means to inflate said lungs of said infant synchronously with said infant's natural inspiration,
• 2.) detecting a pause in said infant's natural respiration,
• 3.) thereupon commanding said inflation means to inflate said infant's lungs to substantially total lung volume, and
• 4.) commanding said compression means to compress said infant's lungs to substantially residual volume.