A nurse is caring for a patient who has developed neuroleptic malignant syndrome (NMS) after starting haloperidol therapy. Which nursing intervention should be the immediate priority?

NMS is a life-threatening emergency requiring immediate discontinuation of the causative antipsychotic medication and aggressive supportive care including cooling measures. Other options are less urgent or supportive.

Clinical Priority Analysis

Neuroleptic malignant syndrome (NMS) is a life-threatening idiosyncratic reaction to antipsychotic agents such as haloperidol. The pathophysiology involves central dopamine receptor blockade, particularly in the hypothalamus, nigrostriatal pathway, and spinal cord, leading to the classic tetrad of hyperthermia, generalized muscle rigidity, autonomic instability, and altered mental status . The immediate priority in management is removal of the offending agent and aggressive supportive care to halt progression and prevent mortality.

Rationale for the Correct Answer

Option 1 is correct because it addresses the two most critical initial steps in NMS management. First, discontinuation of the dopamine antagonist (haloperidol) is essential to stop the ongoing pathophysiological cascade. Continued dopamine blockade exacerbates hypothalamic dysregulation, worsening hyperthermia and autonomic dysfunction. Second, initiating external cooling measures directly combats the severe hyperthermia, which results from impaired heat dissipation due to muscle rigidity and altered central thermoregulation. Hyperthermia is a primary driver of complications such as rhabdomyolysis, disseminated intravascular coagulation, and multi-organ failure, making its immediate control a life-saving priority .

Analysis of Incorrect Options

Option 2: Administer acetaminophen for fever reduction. Antipyretics like acetaminophen are ineffective in NMS because the hyperthermia is not mediated by a change in the hypothalamic set-point (as in infection) but rather by intense heat production from sustained muscle contraction and impaired peripheral heat loss. Pharmacological antipyresis does not address the underlying muscular rigidity and dopamine receptor blockade, making it an inappropriate sole intervention .

Option 3: Increase fluid intake to prevent dehydration. Fluid resuscitation is an important supportive measure to manage insensible fluid losses from hyperthermia and to prevent acute kidney injury secondary to rhabdomyolysis, as evidenced by markedly elevated creatine phosphokinase (CPK) levels that can exceed 20,000 U/L . However, this is a secondary intervention. Without first discontinuing the causative drug and controlling the hyperthermic state, fluid administration alone will not reverse the underlying syndrome.

Option 4: Monitor vital signs every 4 hours. Monitoring frequency for a patient with active NMS must be continuous or at intervals far shorter than every 4 hours due to the extreme and rapid fluctuations characteristic of autonomic instability, including labile blood pressure, tachycardia, and tachypnea. While monitoring is essential, it is a component of ongoing assessment, not the immediate therapeutic priority that interrupts the disease process.

Clinical Reasoning and Test-Taking Strategy

For NCLEX-RN priority questions involving adverse drug reactions, the initial nursing action almost always involves stopping the offending agent. Using the ABC (Airway, Breathing, Circulation) framework extended to safety, discontinuing the drug source is a safety priority that prevents further harm. In NMS, the "C" in ABC is critically threatened by autonomic instability and hyperthermia-induced cardiovascular collapse. Cooling measures directly support circulation and end-organ perfusion by reducing metabolic demand. A systematic review of NMS cases highlights that delayed recognition and failure to immediately withdraw the antipsychotic are associated with significant morbidity, underscoring that early, decisive intervention—specifically drug cessation and temperature control—is the cornerstone of emergency management .