Diaphragmatic palsy or paralysis (DP) due to phrenic nerve injury is a rare respiratory condition which may be life-threatening in newborn and young children (Affatato et al. 1988; Haller et al. 1979; de Leeuw et al. 1999). This entity was first described in 1906 in an adult (Stauffer 1979). In newborn patients in the middle of the last century, it was most often due to birth trauma. In the days of advanced neonatal and cardiac surgery, DP is mostly a complication of thoracic surgery (Greene et al. 1975; Schwartz and Filler 1978; Stauffer and Rickham 1972; Stone et al. 1987; Zhao et al. 1985). The incidence is described between 0.3 and 12.8 % and can be unilateral or bilateral (de Leeuw et al. 1999; Schwartz and Filler 1978; Kunovsky et al. 1993; van Onna et al. 1998). DP due to inflammation, neuropathic or idiopathic is rarely seen in this age group.