Catheter insertion is an emergency treatment method mainly for cases where the lower abdomen is distended and painful due to the inability to urinate, that is, to drain the urine from the bladder in time to prevent further bladder expansion and even rupture. The purpose of inserting a catheter is to drain urine from the bladder in a timely manner, and there are two main types of catheters: double-lumen and triple-lumen. A double-lumen catheter refers to an ordinary catheter, while a three-lumen catheter is generally used as a bladder irrigation. Bladder irrigation is mainly suitable for cases where there are more blood clots in the bladder, and the force of irrigation can be used to flush out the blood clots in the bladder.