When assessing the pulse of a 6-year-old boy, the nurse notices that his heart rate varies with his respiratory cycle, speeding up at the peak of inspiration and slowing to normal with expiration. The nurse's next action would be to:

Correct Answer: B

Rationale: The correct answer is B: Consider this finding normal in children and young adults. Rationale: 1. This phenomenon is known as respiratory sinus arrhythmia, which is a normal variation in heart rate seen in children and young adults. 2. It occurs due to the physiological response of the autonomic nervous system to changes in intrathoracic pressure during respiration. 3. In children, the heart rate normally speeds up during inspiration and slows down during expiration. 4. Since this is a normal finding, there is no need to notify the physician or consider it as bradycardia. Summary of other choices: A: Not necessary to immediately notify the physician as this is a normal finding. C: Checking the blood pressure is not indicated as the pulse variation with respiration is a separate phenomenon. D: Documenting bradycardia is incorrect as this is not the case here.

Correct Answer: C

Rationale: The correct answer is C: Peripheral vasoconstriction. When the body is exposed to cold temperatures, peripheral vasoconstriction occurs to conserve heat by reducing blood flow to the skin. This leads to pale and cool skin. Venous pooling (A) refers to blood pooling in the veins due to gravity, not related to cold exposure. Peripheral vasodilation (B) would result in warm, flushed skin, opposite of the presented symptoms. Decreased arterial perfusion (D) would manifest as cold, pale skin but does not explain the specific mechanism of vasoconstriction in response to cold.

Correct Answer: C

Rationale: The correct answer is C, severe dehydration. Decreased skin turgor is a clinical sign of dehydration due to fluid loss, causing the skin to lose its elasticity. In contrast, severe obesity (choice A) would not typically result in decreased skin turgor. Childhood growth spurts (choice B) do not directly affect skin turgor. Connective tissue disorders like scleroderma (choice D) may affect skin quality, but decreased skin turgor specifically indicates dehydration. Therefore, choice C is the most likely condition associated with decreased skin turgor.

Correct Answer: D

Rationale: The correct answer is D because it provides a physiological explanation for the child's frequent ear infections. The eustachian tube in young children is indeed shorter and wider than in adults, making it easier for infections to develop. This is due to the anatomy of the child's ear, not necessarily indicating a more severe underlying issue. Choice A is incorrect as it implies there must be something else wrong, which is not necessarily the case. Choice B is incorrect as checking the immune system may not be the first step in addressing frequent ear infections. Choice C is incorrect as cerumen is not directly related to the development of ear infections in this context.

Correct Answer: B

Rationale: The correct answer is B: Filter out dust and bacteria. The ciliated mucous membrane in the nose acts as a physical barrier to trap and remove harmful particles like dust and bacteria from the inhaled air. Here's the rationale: 1. The cilia trap particles: The cilia in the mucous membrane sweep back and forth, capturing dust and bacteria in the mucus. 2. Mucus removes particles: The sticky mucus traps the particles, preventing them from entering the respiratory system. 3. Prevents infections: By filtering out harmful particles, the mucous membrane helps protect the respiratory system from infections. 4. Other choices are incorrect: A is incorrect as the primary function is not to warm the air. C is incorrect as it focuses on coarse particles only. D is incorrect as it does not specifically address the filtration function of the mucous membrane.