Diaphragmatic bulge, also known as abdominal organ protrusion and diaphragmatic bulge, belongs to the category of diaphragmatic weakness, which refers to a decrease in the intensity of diaphragmatic activity and includes diaphragmatic palsy and diaphragmatic bulge disorder. The disease is divided into congenital and acquired. For congenital diaphragm bulge, there are no effective preventive measures. In the case of acquired diaphragmatic bulge, however, early knowledge of the causes and prevention can effectively reduce the chances of developing the disease. Causes of acquired diaphragmatic bulge: Acquired diaphragmatic bulge is caused by injury or lesion of the phrenic nerve and is characterized by atrophy of the transverse muscles of the diaphragm. In infants, injury during birth injury, congenital heart disease, or surgery for mediastinal tumors is the most common cause. In adults, invasion of malignant tumors (e.g., lung cancer, thymoma, malignant germ cell tumors, non-Hodgkin’s disease), the effect of ice shavings cooling the surface of the heart during direct cardiac surgery, surgical injuries (e.g., mediastinotomy, resection of intrathoracic or cervical masses, subclavian or jugular vein catheter and electrode placement) and trauma to the cervical spinal cord predispose to phrenic nerve palsy and diaphragmatic bulge. Idiopathic phrenic nerve palsy and diaphragmatic bulge in adults may be the result of subclinical viral infection.