RESPIRATION OF FULL TERM AND OF PREMATURE INFANTS

ALTHOUGH numerous attempts to measure ventilation in early infancy have been reported since that of Eckerlein in 1890,¹reasonable accuracy was not obtained until the body plethysmograph technic²was introduced. While this eliminated the dead space error of the mask technic, it introduced the difficulty of sealing the apparatus around the infant's neck without unphysiological pressure. Cross³avoided this by allowing the infant's face to protrude through a head piece of inflatable rubber and connected the recording spirometer to a specially designed integrator.⁴The first innovation allowed prompter relaxation by the infant and achieved greater freedom from leaks; the latter greatly reduced the labor of record analysis. In the present investigation we used a plethysmograph sealed at the neck but improved both in this regard and in its recording apparatus. These features, plus the additional data secured, are considered worth reporting. <h3>METHODS</h3> The apparatus used was