A patient with hypercapnic respiratory failure has a respiratory rate of 8 and an SpO2 of 89 The patient is increasingly lethargic.
Which collaborative intervention will the nurse anticipate?

Choice A rationale

In third-degree heart block, the atria and ventricles beat independently, and a slow ventricular escape rate of 35 beats/min significantly reduces cardiac output. This lack of perfusion to the brain often manifests as confusion, dizziness, or syncope, known as Stokes-Adams attacks. Monitoring for neurological changes is critical because it indicates the severity of the hemodynamic compromise and the immediate need for a temporary or permanent pacemaker to restore adequate systemic blood flow.

Choice B rationale

Pulmonary rales or crackles indicate left-sided heart failure and fluid backup into the alveolar spaces. While chronic heart block can eventually lead to heart failure, the most immediate and life-threatening assessment finding for a rate of 35 beats/min is related to cerebral perfusion. Although the nurse should listen to lung sounds, the identification of syncope or confusion takes priority as an acute indicator of the patient's inability to maintain a minimally functional cardiac output for consciousness.

Choice C rationale

Acute hypertension is not a typical finding in a patient with a heart rate of 35 beats/min and third-degree heart block. In fact, most patients with such a low heart rate and wide QRS complexes experience hypotension due to the significant drop in the volume of blood pumped per minute. Assessing for high blood pressure would be less relevant than assessing for low blood pressure and the associated symptoms of shock or poor peripheral organ perfusion.

Choice D rationale

A gallop rhythm, such as an S3 or S4 heart sound, is often associated with ventricular filling issues or heart failure. While it may be present in a patient with underlying cardiac disease, it is not the most critical assessment finding for an acute bradycardic event of 35 beats/min. Neurological status is a more sensitive and immediate indicator of whether the slow rate is currently failing to meet the body's basic metabolic and oxygenation demands.

Choice A rationale

Anxiety is generally not a common physiological side effect of beta-adrenergic antagonists like metoprolol. Instead, these medications often cross the blood-brain barrier and cause central nervous system depression, leading to symptoms such as fatigue, lethargy, or even depression. Anxiety is more commonly associated with the stimulation of the sympathetic nervous system or the use of beta-agonists, which would be the opposite pharmacological effect of this specific medication class.

Choice B rationale

Restlessness and agitation are typically signs of neurological irritability or hypoxia rather than direct side effects of beta-blocker therapy. Metoprolol works by blocking beta-1 receptors in the heart, which reduces the heart rate and myocardial contractility. Because it dampens the "fight or flight" response, patients are much more likely to experience a calming effect or sedation. Agitation would be an atypical response and might indicate a different underlying clinical complication.

Choice C rationale

Metoprolol is a cardioselective beta-1 adrenergic antagonist that decreases the heart rate by slowing the conduction through the atrioventricular node and reducing sinus node automaticity. A heart rate of 45 beats per minute represents significant bradycardia, as the normal adult resting range is 60 to 100 beats per minute. This profound slowing of the heart rate is a classic, expected, and potentially dangerous side effect of excessive beta-blockade requiring nursing intervention.

Choice D rationale

A blood pressure of 190/110 mm Hg indicates severe hypertension, whereas metoprolol is specifically used to lower blood pressure. Beta-blockers reduce cardiac output and inhibit the release of renin from the kidneys, which normally leads to a decrease in systemic vascular resistance and lower blood pressure readings. A hypertensive crisis of this magnitude would suggest that the medication is either ineffective or that the patient is experiencing a paradoxical reaction or withdrawal.