What should a patient do to assist in moving up when he has slid down in bed?

The most effective method for a patient to assist in repositioning themselves up in bed when they have slid down is to flex their knees and push with their heels. This technique utilizes the strength of the legs, which are generally stronger than the arms, providing more power to move the body upward. By flexing the knees, the patient creates leverage and stability, allowing them to push against the bed with their heels. This action helps in shifting the body in a controlled manner, reducing the risk of injury.

In contrast, pushing with the arms, while it may seem instinctive, often does not provide enough force or stability for an effective repositioning due to the lack of lower body engagement. Pulling the nurse's arm may not be safe for either party, as it could lead to loss of balance or strain. While asking for assistance is always a prudent choice if the patient feels unable to reposition themselves safely, the question specifically seeks the proactive action the patient can take independently. Thus, flexing the knees and using heel power to push up is the most reliable method for self-assistance in this scenario.