Ultrasonographic diagnosis of diaphragm paralysis in a neonate during mechanical ventilation after cardiac surgery

Diaphragm excursion method is unsuitable for diagnosis of diaphragm paralysis during positive pressure ventilation. We diagnosed diaphragm paralysis in a neonate, without interrupting positive pressure respiratory support after cardiac surgery, using the diaphragm thickness fraction, which could be evaluated during mechanical ventilation and was unaffected by bowel gases. The diaphragm thickness fraction method can help diagnose diaphragm dysfunction using only echography.