The nurse should perform capillary refill testing on the distal fingertips of the affected arm. Normal refill time is less than 2 seconds. Refill time of 3 seconds or more indicates a serious problem with arterial blood flow and requires attention. Plaster casts are applied wet and allowed to dry. Placing the cast in plastic before it has dried is inappropriate. On the other hand, once the cast has dried, younger patients may need plastic covering to keep the cast from getting wet. Wet casts should not be placed on hard surfaces until they dry completely, otherwise the cast can deform and compress the underlying tissue. The nurse should ensure that the cast does not rub or press into the skin at any location since this can damage underlying skin/tissue. Likewise, the nurse should explain isometric exercises to the patient and caregiver.