One hour after receiving IV morphine sulfate, a patient reports itching.
The patient has clear breath sounds, no rash, respirations of 18 breaths per minute, a heart rate of 71 bpm, and a BP of 110/70 mm Hg. Which action should the nurse take?

Choice A rationale

Opioids act as central nervous system depressants by binding to μ-opioid receptors, primarily in the brainstem's respiratory center. This binding inhibits the release of essential neurotransmitters, significantly decreasing the responsiveness of the chemoreceptors to carbon dioxide changes, which is contrary to increased rate and depth. This effect leads to hypoventilation, hypercapnia, and ultimately severe respiratory acidosis, resulting in respiratory failure.

Choice B rationale

While some opioids can cause minor histamine release, which theoretically could lead to mild bronchoconstriction, the primary and most life-threatening effect is profound central respiratory depression, not peripheral airway narrowing. Bronchoconstriction and wheezing are more characteristic of conditions like asthma or Type I hypersensitivity reactions, not the direct, primary action of opioid agonism on respiratory drive.

Choice C rationale

Opioids cause hypoventilation by reducing the rate and depth of inhalation, rather than primarily causing an inability to exhale. The issue is a depressed respiratory drive from the brainstem. Exhalation is largely a passive process driven by the elastic recoil of the lungs and chest wall after a reduced or shallow inspiration, making an inability to exhale scientifically inaccurate as the primary effect.

Choice D rationale

Opioid agonists depress the central respiratory drive by reducing the sensitivity of the medullary respiratory center to hypercapnia (high CO_2). This direct neuropharmacological effect drastically reduces the frequency (rate) and volume (depth or tidal volume) of breaths, leading to severe hypoventilation, CO_2 retention, and potentially lethal respiratory arrest, which aligns with the observed 6 breaths/min.

Choice A rationale

Ibuprofen, a nonsteroidal anti-inflammatory drug (NSAID), is an appropriate medication for reducing fever and managing pain in children. It works by inhibiting the cyclooxygenase (COX) enzymes, which decreases the production of prostaglandins that mediate inflammation and fever. There is no contraindication for ibuprofen use in children with chicken pox.

Choice B rationale

Acetaminophen (paracetamol) is an effective analgesic and antipyretic for children, reducing fever and aches. Its mechanism is thought to involve inhibition of COX activity primarily within the central nervous system. It is generally considered a safe choice for fever management in children, including those with viral infections like chicken pox.

Choice C rationale

Aspirin (acetylsalicylic acid) is a salicylate that should be strictly avoided in children and adolescents recovering from or with symptoms of viral illnesses, such as influenza or chicken pox. Its use in this setting is strongly associated with the development of Reye's syndrome, a rare but serious condition causing acute encephalopathy and fatty liver failure.

Choice D rationale

Fluids, such as water and electrolyte-containing solutions, are essential for managing fever and aches by preventing dehydration, which can be exacerbated by fever and poor fluid intake due to illness. Increasing fluid intake is a crucial supportive measure, not an item to avoid, and helps maintain circulatory volume and facilitate thermoregulation.