# A nurse is caring for a patient who has been receiving haloperidol for schizophrenia. The patient suddenly develops hyperthermia (104°F/40°C), muscle rigidity, altered mental status, and autonomic instability. Which nursing action should be the PRIORITY?

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> url: https://mymerci.kr/pages/nclex_q.php?qn_id=319588  
> language: ko  
> subject: Pharmacology

## 문제

A nurse is caring for a patient who has been receiving haloperidol for schizophrenia. The patient suddenly develops hyperthermia (104°F/40°C), muscle rigidity, altered mental status, and autonomic instability. Which nursing action should be the PRIORITY?

## 보기

1. Administer acetaminophen for fever reduction
2. Increase fluid intake to prevent dehydration
3. Apply cooling blankets to reduce body temperature
4. Discontinue the antipsychotic medication immediately **✔ 정답**

**정답: 4**

## 해설

Neuroleptic malignant syndrome is a life-threatening emergency. The priority action is immediate discontinuation of the antipsychotic medication to prevent worsening and mortality. Other options are supportive but secondary.

## 심화 해설

Core Nursing Explanation
**Key Concept Analysis**: This question assesses the recognition and **priority intervention** for Neuroleptic Malignant Syndrome (NMS), a rare but life-threatening adverse reaction to antipsychotic medications like haloperidol. The pathophysiology involves a sudden, severe dysregulation of dopamine in the brain, leading to hyperthermia, extreme muscle rigidity, autonomic instability, and altered mental status. The core principle is that NMS is a Key Point! drug-induced medical emergency; the offending agent **must** be removed to halt the progression of the syndrome.

**Answer Rationale**: The correct answer is to Key Point! Discontinue the antipsychotic medication immediately. This is the single most critical and definitive action. NMS is caused by the drug; continuing it will worsen the condition and can lead to fatal complications like rhabdomyolysis, renal failure, or cardiac arrest. All other interventions are supportive measures that are initiated *after* or *concurrently with* stopping the causative agent, but they do not address the root cause.

**Distractor Analysis**:

Watch out for confusion! Option ① (Administer acetaminophen) is incorrect because the fever in NMS is not caused by an infection or typical inflammatory pathway that responds well to antipyretics. It is a central dysregulation, and acetaminophen is ineffective as a primary treatment.

Option ② (Increase fluid intake) is a supportive measure for managing dehydration and potential renal complications from rhabdomyolysis, but it is not the immediate, life-saving priority. Intravenous fluids are part of the treatment plan, but stopping the drug comes first.

Option ③ (Apply cooling blankets) addresses the symptom of hyperthermia and is a correct supportive intervention. However, cooling alone does not stop the underlying pathological process. The priority is to remove the trigger.

**Related Concepts**: NMS must be differentiated from other serious conditions. Watch out for confusion! Malignant Hyperthermia is a similar hypermetabolic crisis triggered by volatile anesthetics and succinylcholine, not antipsychotics. Serotonin Syndrome also presents with hyperthermia and autonomic changes but is caused by serotonergic drugs (e.g., SSRIs) and features neuromuscular excitation (clonus, hyperreflexia) rather than the "lead-pipe" rigidity of NMS.

Concept Summary

| Concept | Key Features | Nursing Priority |
| --- | --- | --- |
| Neuroleptic Malignant Syndrome (NMS) | Hyperthermia, severe muscle rigidity, altered mental status, autonomic instability (tachycardia, labile BP). Caused by antipsychotics. | 1. STOP the drug. 2. Supportive care (cooling, IV fluids, monitoring). 3. Administer specific medications (e.g., dantrolene, bromocriptine). |
| Serotonin Syndrome | Hyperthermia, agitation, clonus, hyperreflexia, diaphoresis, diarrhea. Caused by serotonergic drugs. | 1. STOP serotonergic agents. 2. Supportive care. 3. Administer cyproheptadine (serotonin antagonist). |
| Malignant Hyperthermia | Hyperthermia, muscle rigidity, tachycardia, hypercapnia. Triggered by anesthesia agents. | 1. STOP triggering anesthetic. 2. Hyperventilate with 100% O2. 3. Administer dantrolene. |

Side-by-Side Comparison!

| Feature | Neuroleptic Malignant Syndrome (NMS) | Serotonin Syndrome |
| --- | --- | --- |
| Primary Cause | Antipsychotics (e.g., haloperidol) | Serotonergic drugs (e.g., SSRIs, MAOIs) |
| Onset | Days to weeks after starting/changing dose | Hours after starting/changing dose (often rapid) |
| Key Neuromuscular Sign | "Lead-pipe" rigidity (severe, constant) | Hyperreflexia, clonus (inducible, oscillating) |
| Mental Status | Stupor, catatonia, coma | Agitation, confusion, anxiety |
| Autonomic Instability | Present (e.g., labile BP, tachycardia) | Present (e.g., diaphoresis, diarrhea) |
| First-Line Treatment | Stop antipsychotic, supportive care, dantrolene/bromocriptine | Stop serotonergic drug, supportive care, cyproheptadine |

Anatomy, Physiology & Pharmacology Points
The hypothalamus regulates body temperature. In NMS, dopamine blockade in the hypothalamus disrupts thermoregulation, causing hyperthermia. Dopamine blockade in the nigrostriatal pathway causes severe muscle rigidity. Haloperidol is a high-potency typical antipsychotic with strong dopamine (D2) receptor antagonism, making it a common culprit for NMS.

Memory Tips
**Mnemonic for NMS: FEVER**

**F**ever (High)

**E**ncephalopathy (Altered mental status)

**V**ital sign instability (Autonomic)

**E**levated enzymes (CPK, from muscle breakdown)

**R**igidity (Muscle)

**Priority Rule:** "If the drug is the cause, stopping it is the *first* course!" Always think: Remove the offending agent first in any suspected adverse drug reaction emergency.

High-Frequency NCLEX Topics
NCLEX heavily tests **priority-setting** and **recognizing medical emergencies**. NMS is a classic example. You must know the cardinal signs (the classic triad: fever, rigidity, altered mental status) and that the **immediate action is to stop the medication**. Expect questions that mix NMS with other syndromes or ask for the "first" or "priority" nurse action.

Watch Out for Question Variations!
* Instead of asking for the priority action, a question might ask: "The nurse identifies which finding as most suggestive of Neuroleptic Malignant Syndrome?" (Answer: Severe muscle rigidity with hyperthermia in a patient on antipsychotics).
* A question could present a similar scenario but with a different drug (e.g., an SSRI) and ask for the priority—the answer would still be to stop the drug, but the syndrome would be Serotonin Syndrome.
* A question might ask for a **collaborative intervention** after stopping the drug: "Which medication does the nurse anticipate the provider will prescribe?" (Answer: Dantrolene or bromocriptine).

## 임상 시나리오

Nursing Clinical Practice Guide
**Clinical Scenario**: You are the nurse on a psychiatric unit. Mr. Jones, 45, diagnosed with schizophrenia, was started on haloperidol 5mg PO BID three days ago. During your morning assessment, he is difficult to arouse, feels hot to the touch, and his limbs are stiff and resistant to passive movement. His vital signs are: Temp 40.1°C (104.2°F), HR 128, BP 168/94.

**Nursing Intervention Strategy**:
1.  **Immediate Action (Priority)**: Withhold the next dose of haloperidol. Notify the physician/advanced practice provider STAT and report your suspicion of NMS. This is a **medical emergency**; prepare for possible transfer to a medical ICU.
2.  **Assessment & Monitoring**:
*   Continuously monitor vital signs, especially core temperature.
*   Perform a focused neurological assessment (Glasgow Coma Scale (GCS), pupil reaction).
*   Assess for muscle rigidity and tenderness.
*   Obtain stat labs as ordered: Creatine Phosphokinase (CPK) (will be extremely elevated due to muscle breakdown), electrolytes, renal function (BUN, creatinine), and CBC.
3.  **Supportive Care (Initiated concurrently)**:
*   **Temperature Management**: Apply cooling blankets, use a fan, administer tepid sponge baths. Watch out for confusion! Avoid antipyretics like acetaminophen or ibuprofen—they are not effective for this type of hyperthermia.
*   **Fluid & Electrolyte Management**: Establish IV access and administer IV fluids aggressively to maintain renal perfusion and flush myoglobin from muscle breakdown, preventing acute renal failure.
*   **Safety**: Maintain a quiet environment. Implement seizure precautions due to risk of seizures.
4.  **Pharmacological Support**: Anticipate orders for:
*   Dantrolene: A direct muscle relaxant that uncouples muscle contraction.
*   Bromocriptine: A dopamine agonist to counteract the dopamine blockade.

**Patient Safety and Precautions**:
*   **Contraindication**: Do not restart any antipsychotic from the same class (typical antipsychotics) after an episode of NMS. If antipsychotic therapy is absolutely necessary in the future, a different class (atypical antipsychotic) may be tried with extreme caution.
*   **Monitoring**: Closely monitor urine output and color (dark, tea-colored urine suggests myoglobinuria). Monitor for signs of compartment syndrome from severe muscle rigidity.

Nursing Procedure & Medication Flow
**When Administering Dantrolene (IV)**:
*   Reconstitute each vial with 60 mL of sterile water (not saline, as it causes precipitation).
*   Administer by rapid IV push as ordered. Monitor for side effects: muscle weakness, hepatotoxicity, phlebitis at the injection site.

A Word from Your Senior Nurse
"Nursing is not just about carrying out physician orders — it's about being the frontline guardian for your patients! In clinical practice, recognizing the subtle (or not-so-subtle) early signs of a crisis like NMS is what saves lives. That 'gut feeling' when a patient just isn't right, coupled with your knowledge of high-risk medications, is your superpower. When studying for your boards, don't just memorize 'stop the drug' for NMS. Understand *why*—the dopamine blockade, the muscle breakdown, the renal risk. Connect the dots from pharmacology to pathophysiology to nursing action. That deep understanding will make you a nurse who doesn't just pass tests, but who truly advocates and acts decisively at the bedside."

## 핵심 개념

- **Neuroleptic Malignant Syndrome** — A life-threatening reaction to antipsychotic drugs characterized by hyperthermia, severe muscle rigidity, altered mental status, and autonomic dysfunction.
- **Haloperidol** — A high-potency typical antipsychotic medication that blocks dopamine receptors; a common trigger for NMS.
- **Dopamine** — A neurotransmitter; its blockade in the brain by antipsychotics is the primary pathophysiological mechanism behind NMS.
- **Dantrolene** — A direct-acting skeletal muscle relaxant used as a specific treatment for NMS (and Malignant Hyperthermia) to reduce severe rigidity and hyperthermia.
- **Creatine Phosphokinase** — A muscle enzyme; levels are markedly elevated in NMS due to rhabdomyolysis (breakdown of skeletal muscle).

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