Explanation
(A) Synthetic cast materials harden in 3-15 minutes. Weight bearing is permitted in 15-30 minutes. Drying time for plaster of Paris is about 24-72 hours. (B, C) Plaster of Paris cast materials are heavier than synthetic materials and require a drying time of 24-72 hours. Synthetic materials dry within 30 minutes. (D) Plaster of Paris cast materials are heavier thansynthetic materials and require a longer period to set and dry. Even though setting time (hardening) is only 3-15 minutes, the drying time for plaster of Paris is 24-72 hours. This depends on the size and thickness of the cast, exposure to air, and humidity in the air.

Section: Questions Set E
Explanation:
(A) The nurse should discourage the child from coughing, clearing the throat, or putting objects in his mouth.
These may induce bleeding. (B) Cool, clear liquids may be given when child is fully alert. Warm liquids may dislodge a blood clot. The nurse should avoid red- or brown-colored liquids to distinguish fresh or old blood from ingested liquid should the child vomit. (C) Gargles and vigorous toothbrushing could initiate bleeding. (D) Postoperative hemorrhage, though unusual, may occur. The nurse should observe for bleeding by looking directly into the throat and for vomiting of bright red blood, continuous swallowing, and changes in vital signs.

Explanation
(A) Cool air will often relieve pruritus without damaging the cast or irritating the skin. (B) The nurse should never force anything under the cast, because the cast may become damaged and skin breakdown may occur.
(C) Forcing an object under the cast could lead to cast damage and skin breakdown. The object may become lodged under the cast necessitating cast removal. (D) This technique does not dislodge skin cells. It could damage the cast and cause skin breakdown.

Explanation/Reference:
Explanation:
(A) Sinus bradycardia and atrioventricular (AV) heart block are usually a result of right coronary artery occlusion. The right coronary artery perfuses the sinoatrial and AV nodes in mostindividuals. (B) Occlusion of the left main coronary artery causes bundle branch blocks and premature ventricular contractions. (C) Occlusion of the circumflex artery does not cause bradycardia. (D) Sinus tachycardia occurs primarily with left anterior descending coronary artery occlusion because this form of occlusion impairs left ventricular function.

Explanation
(A) There is no NPO restriction prior to a liver biopsy. (B) The client would need to hold his breath for 5-10 seconds. (C) There is no pretest laxative given. (D) Following the test, the client is watched for hemorrhage and shock.