A nurse is caring for a patient who developed neuroleptic malignant syndrome (NMS) after receiving haloperidol. Which nursing intervention should be the highest 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 supportive but not the highest priority.

Understanding Neuroleptic Malignant Syndrome (NMS)
Neuroleptic malignant syndrome is a life-threatening idiosyncratic reaction to dopamine antagonists, most commonly antipsychotics like haloperidol. The classic tetrad includes hyperthermia, severe muscle rigidity, autonomic instability (e.g., diaphoresis, labile blood pressure), and altered mental status. The underlying pathophysiology is believed to be central dopamine receptor blockade in the hypothalamus (leading to impaired thermoregulation and hyperthermia) and the nigrostriatal pathway (leading to extrapyramidal rigidity, which generates heat) [1,4]. This patient’s presentation of a temperature of 104°F (40°C), severe rigidity, and altered mental status following haloperidol initiation is a classic, fulminant presentation.

Priority Nursing Intervention: Rationale for Correct Answer
The highest priority intervention is to discontinue the antipsychotic medication immediately and prepare for emergency cooling measures. In NMS, the body's thermoregulatory set point is disrupted, and the intense muscle rigidity generates a massive amount of metabolic heat, leading to extreme hyperthermia [1,4]. This is not a simple fever; it is a direct consequence of the drug's mechanism of action. The primary treatment is removal of the offending agent to halt the progression of the dopamine blockade [1,3]. Simultaneously, aggressive external cooling is critical because the hyperthermia itself drives further complications, including severe rhabdomyolysis, metabolic acidosis, acute kidney injury, and multi-organ failure, as highlighted in cases of prolonged NMS ^[4]. Delaying these two actions to administer other medications first would allow the underlying pathological process to continue unchecked, increasing the risk of irreversible end-organ damage and mortality.

Analysis of Incorrect Options
While the other interventions may be part of the comprehensive management of NMS, they do not address the immediate, life-threatening cause.

- Administering acetaminophen (Option 2) is ineffective for the central hyperthermia of NMS because the elevated temperature is not driven by a change in the hypothalamic set point mediated by prostaglandins, which is the pathway acetaminophen targets. The hyperthermia is a result of impaired heat dissipation and excessive heat production from rigidity, requiring physical cooling measures instead [1,3].
- Increasing fluid intake and monitoring electrolytes (Option 3) is an important supportive measure to manage rhabdomyolysis and prevent acute kidney injury, a known complication of NMS ^[4]. However, this is a secondary intervention. The patient’s immediate survival depends first on removing the causative drug and aggressively lowering the body temperature to stop ongoing muscle and organ damage.
- Administering lorazepam (Option 4) is a useful pharmacological intervention for managing agitation and reducing muscle rigidity in NMS. A systematic review of case reports confirms that benzodiazepines like lorazepam are frequently used as a supportive treatment to decrease rigidity and autonomic instability ^[1]. However, it is an adjunctive therapy, not the definitive first step. The priority remains removing the causative agent and initiating cooling; lorazepam can be administered concurrently or shortly after these critical initial actions are taken.