centesis

Cent esis is a medical procedure that involves puncturing a body cavity or organ with a needle or catheter to remove fluid, relieve pressure, or obtain diagnostic material. It is used across medical specialties and can be diagnostic, therapeutic, or both.

Common types include paracentesis, the removal of ascitic fluid from the peritoneal cavity to assess infection or malignancy or to relieve abdominal distension; thoracentesis, the drainage of pleural fluid for diagnostic analysis or symptomatic relief of shortness of breath; pericardiocentesis, the removal of pericardial effusion to treat tamponade or monitor fluid; arthrocentesis, the aspiration of synovial fluid from a joint to diagnose arthritis or relieve swelling; and amniocentesis, sampling of amniotic fluid for prenatal testing.

Procedures are typically performed under sterile conditions with local anesthesia. Image guidance, such as ultrasound or fluoroscopy, improves safety and accuracy in many sites. Before the procedure, coagulation status is reviewed and reversible risk factors are corrected when possible. Afterward, the collected fluid is sent to the laboratory for analysis as indicated, and the puncture site is covered and monitored for complications. In therapeutic centesis, the aim is to remove excess fluid and alleviate symptoms; in diagnostic centesis, analysis of the fluid informs diagnosis and treatment plans.

Potential complications include bleeding, infection, organ or vessel injury, pneumothorax (especially with chest or lung access), re-accumulation of fluid, and pain at the puncture site. Overall risk is low when performed by trained clinicians with proper technique and patient selection.