Urinary catherisation indicated in case of acute retention of urine in following conditions :a) Strictureb) Rupturec) Postoperatived) Carcinoma prostatee) Before appendicectomy in acute appendicitis

Trauma to urethra is an absolute contraindication to urethral catheterization. Stricture and acute prostatitis are relative contraindications. Catheterization is done preoperatively in some surgical procedures such as cardiac surgery, aortic or renal vascular surgery, craniotomy or major abdominal surgery or procedures in which large fluid shifts are expected. But not done for appendicectomy.