Electromagnetic inductance plethysmography to measure tidal breathing in preterm and term infants

Tidal breathing measurements which provide a non-invasive measure of lung function in preterm and term infants are particularly useful to guide respiratory support. We used a new technique of electromagnetic inductance plethysmography (EIP) to measure tidal breathing in infants between 32 and 42 weeks postconceptional age (PCA). Tidal breathing was measured in 49 healthy spontaneously breathing infants between 32 and 42 weeks PCA. The weight-corrected tidal volume (V(T) ) and minute volume (MV) decreased with advancing PCA (V(T) 6.5 ± 1.5 ml/kg and MV 0.44 ± 0.04 L/kg/min at 32-33 weeks, respectively; 6.3 ± 0.9 ml/kg and 0.38 ± 0.02 L/kg/min at 34-36 weeks; and 5.1 ± 1.1 ml/kg and 0.28 ± 0.02 L/kg/min at term, V(T) P < 0.001 and MV P < 0.01 for 32-33 weeks PCA vs. term; V(T) P = 0.016 and MV P = 0.015 for 34-36 weeks PCA vs. term). Respiratory frequency and the phase angle decreased significantly with advancing PCA but the flow parameter t(PTEF) /t(E) did not change significantly. Using a new technique to measure tidal breathing parameters in newborn infants, our data confirms its usability in clinical practice and establishes normative data which can guide future respiratory management of newborn infants.