Ascites: Shifting Dullness - Clinical Examination

The most reliable clinical sign to detect ascites is checking for bilateral flank dullness. If a patient with ascites is lying supine, fluid accumulates in the flank regions, leading to dullness on percussion. At the same time, the air-filled bowel loops are forced upwards by the free fluid due to buoyancy, resulting in tympanitic percussion. To locate specifically where dullness shifts to tympany, or the air-fluid level, percussion should be performed from the sides towards the middle. To confirm that the dullness is caused by ascites, ask the patient to switch to a lateral decubitus position. If ascites is present, the air-filled bowel loops will shift accordingly and remain at the surface of the fluid. As a result, the air-fluid level will shift as well. This is known as shifting dullness. Subscribe to AMBOSS YouTube for the latest clinical examination videos, medical student interviews, study tips and tricks, and live webinars! Free 5 Day Trial: https://go.amboss.com/amboss-YT Instagram:   / amboss_med   Facebook:   / amboss.med   Twitter:   / ambossmed   Blog: https://blog.amboss.com/us #AMBOSSMed #ClinicalExamination