Final answer:
Patients in wheelchairs are usually taught to relieve pressure on their buttocks and thighs by repositioning or transferring weight approximately every 15 to 30 minutes to prevent pressure sores.
Step-by-step explanation:
The question regarding how often a patient confined to a wheelchair should be taught to relieve pressure on the buttocks and thighs is a matter related to health, particularly concerning prevention of pressure sores in individuals with limited mobility. Such patients are typically advised to perform pressure reliefs every 15 to 30 minutes. This involves either repositioning themselves in the wheelchair, using tilt-in-space functions if available, or transferring weight by lifting off the seat, all aimed at improving circulation and preventing injury. The information provided about urine output following water ingestion is not directly related to this question, but indicates a different physiological process where after drinking a large glass of water, a person might start to see an increase in urine output typically within the 90th percentile time of 13.5 minutes.