The objective of this study is to describe the frequency, morbimortality and treatment of diaphragmatic dysfunction (DD) after pediatric cardiac surgery.

Patients and methods: Series of DD cases identified among the population of children who underwent cardiac surgery at the hospital 12 de Octubre of Madrid from the years1997-2006. Demographic, surgical and postsurgical data have been obtained retrospectively, as well as data on hospital stay and the morbimortality.

Results: A total of 1,063 children underwent cardiac surgery, diagnosing 23 DD cases. A secondary case was excluded due to generalized neuropathy. The global frequency was of 2.1%, the mean age was 14 days (1 d-16 m), being 20 of the cases under 1 year of age. Reefing was performed in 13 patients (62%). The indications for reefing were due to extubation failu¬re (n= 11) and persistent respiratory difficulties (n= 2).

Surgical reefing had to be performed in 9 from the 13 newborns. In the cases of paresis the length of the invasive mechanical ventilation, stay at the PICU and hospital stay was 8, 12 and 20 days (mean) respectively. The paralysis required a longer time of invasive ventilation and hospitalization (19, 34 and 47,5 days).

Conclusions: A diaphragm echography in spontaneous breathing should be performed on any newborn that underwent a complex cardiopathy surgery previous to the extubation in order to determine an early diagnosis and to reduce the length of mechanical ventilation and associated morbidity.

The diaphragmatic paralysis is caused by a lesion of the phrenic nerve, being the predominant cause in pediatrics dur­ing birth, especially in macrosomic fetus. The relationship with brachial palsy, aids the diagnostic suspicion, but we have to take into account that up to 25% of the cases are shown without brachial plexus injury. Symptoms are variable and may appear immediately after delivery or later in the neonatal period. Chest x-rays show an elevation of the affected hemi-diaphragm. The diagnosis is confirmed by M-mode sonography. The management commonly is conservative (oxygen or CPAP), with spontaneous recovery in most cases, although surgical plication is required in some cases.