The nurse is caring for a patient after abdominal surgery in the PACU. The patient's blood pressure has increased and the patient is restless. The patient's oxygen saturation is 97%. What cause for this change in status should the nurse first suspect?

Choice A reason: Hyperthermia can cause tachycardia and restlessness, but it is not the most common or immediate cause of hypertension and restlessness in the early post-anesthesia recovery period following abdominal surgery. Temperature elevations in the PACU are more often related to malignant hyperthermia, which is a rare and distinct anesthetic emergency. Choice B reason: Hypovolemia typically presents with a decrease in blood pressure (hypotension) and an increase in heart rate (tachycardia) as the body attempts to maintain cardiac output. Since this patient's blood pressure has increased rather than decreased, hypovolemia is an unlikely primary cause for the current clinical presentation in the recovery room. Choice C reason: In the immediate postoperative period, pain is a primary cause of sympathetic nervous system activation. This physiological stress response leads to the release of catecholamines, resulting in hypertension, tachycardia, and behavioral restlessness. Since the oxygen saturation is normal at 97%, pain is the most logical and frequent cause of these specific vital sign changes. Choice D reason: Hypoxia can certainly cause restlessness and early hypertension as the body compensates for low oxygen levels. However, the patient's oxygen saturation is 97%, which is within the normal range. This objective data allows the nurse to prioritize other causes, such as acute surgical pain, over respiratory compromise as the source of agitation.