Today we went to go see a patient of ours. He's a man in his early eighties who fell a week ago and was discovered to have a subdural hematoma. They evacuated his hematoma with a burr hole and now we're waiting to clear him medically before we discharge him to rehab. He's been delirious, especially since the surgery. Our faculty mentioned that it may be due to urinary retention, as that is a common cause of acute delirium in the elderly. So we asked the patient to try to void. He urinated maybe a size of a quarter in his diaper, despite telling us that he felt like he really needed to go. On palpation, you could feel that his bladder was full. So we straight-cathed the patient and got back 1000 cc's of urine.
Things I learned today:
- Urinary retention can cause acute delirium in the elderly.
- The bladder is designed to alert you of the need to urinate at around 150 ccs. If you're busy in class, rounding, or just want to wait for a more convenient time, the bladder will begin to stretch further. However, at around 400 ccs, the bladder will alert the spinal cord who will in turn alert the brain that you need to urinate NOW! Holding more than 400 cc's of urine at a time will wreak havoc on the bladder muscles, the bladder wall and the nerves involved in micturition.
Hooray for learning new things!