The nurse is caring for a client who has a history of obstructive sleep apnea.
The nurse would expect to see which device at the client's bedside?

Choice A rationale

Respiratory acidosis is characterized by a pH below 7.35 and a CO2 level above 45 mmHg. In this scenario, the pH of 7.53 indicates an alkalotic state, and the CO2 of 16 mmHg is significantly lower than the normal range of 35 to 45 mmHg. Therefore, the data does not support a diagnosis of respiratory acidosis. Acidosis involves an excess of carbonic acid, whereas this patient has a deficit of acid due to excessive alveolar ventilation.

Choice B rationale

Respiratory alkalosis is defined by a pH greater than 7.45 and a PaCO2 less than 35 mmHg. This patient's pH of 7.53 and CO2 of 16 mmHg perfectly fit this criteria. The low CO2 is caused by hyperventilation, which "washes out" carbon dioxide from the blood. The HCO3 of 13 mEq/L indicates that the kidneys are attempting to compensate by excreting excess bicarbonate, as the normal range for HCO3 is 22 to 26 mEq/L.

Choice C rationale

Metabolic acidosis would present with a pH below 7.35 and a bicarbonate (HCO3) level below 22 mEq/L. While this patient does have a low bicarbonate level of 13 mEq/L, the pH is 7.53, which is alkalotic. The low bicarbonate in this specific case is a compensatory response to long-standing or severe respiratory alkalosis, not the primary cause of the disturbance. The primary driver is the low CO2 level causing the rise in pH.

Choice D rationale

Metabolic alkalosis is characterized by a pH above 7.45 and an HCO3 level above 26 mEq/L. While the patient's pH is 7.53, indicating alkalosis, the bicarbonate level of 13 mEq/L is low rather than high. In metabolic alkalosis, the body usually retains CO2 to compensate, but here the CO2 is very low. This confirms that the alkalinity is originating from the respiratory system's loss of acid rather than a metabolic gain of base. .

Choice A rationale

While lateral positioning can help maintain airway patency by preventing the tongue and soft tissues from collapsing into the posterior pharynx, it is not the immediate priority when a new medical device has arrived. Positional therapy is a secondary behavioral intervention for obstructive sleep apnea. The primary prescribed treatment is Continuous Positive Airway Pressure, and ensuring the patient can use the equipment correctly is more impactful for managing the apnea-hypopnea index during sleep.

Choice B rationale

Weight loss and dietary changes are important long-term strategies for reducing the severity of obstructive sleep apnea by decreasing parapharyngeal fat deposits. However, discussing a keto diet or long-term weight goals is not the most urgent action at 8 p.m. when the patient is preparing for sleep. The immediate clinical need is to stabilize the airway during the upcoming night of rest, which requires the functional application of the newly delivered CPAP machine.

Choice C rationale

Modafinil is a wake-promoting agent sometimes used to treat residual daytime sleepiness in sleep apnea patients, but it does not treat the underlying airway obstruction. Notifying the provider for a new medication is not as urgent as ensuring the patient can safely use the mechanical ventilation support already ordered and delivered. Furthermore, the nurse should prioritize non-pharmacological airway management and patient education on the prescribed CPAP therapy before seeking additional stimulant medications.

Choice D rationale

The nurse's immediate priority is to ensure the patient knows how to safely and effectively use the CPAP machine before they go to sleep. Proper education includes fitting the mask to prevent air leaks, understanding how to turn the device on, and managing the humidification settings. Continuous Positive Airway Pressure works by creating a pneumatic splint for the upper airway. Without proper instruction, the patient may have poor compliance or ineffective therapy during the night.