# A nurse is assessing a patient who received an intravenous antibiotic 15 minutes ago. Which assessment finding would be the most critical indicator of anaphylaxis requiring immediate intervention?

> source: MyMerci (mymerci.kr)  
> url: https://mymerci.kr/pages/nclex_q.php?qn_id=540827  
> language: ko  
> subject: Adult Health

## 문제

A nurse is assessing a patient who received an intravenous antibiotic 15 minutes ago. Which assessment finding would be the most critical indicator of anaphylaxis requiring immediate intervention?

## 보기

1. Localized urticaria and mild itching at the injection site
2. Blood pressure decrease from 130/80 to 110/70 mmHg with heart rate increase to 95 bpm
3. Stridor with severe respiratory distress and blood pressure of 70/40 mmHg **✔ 정답**
4. Nausea, vomiting, and abdominal cramping with diarrhea

**정답: 3**

## 해설

Stridor with severe respiratory distress and hypotension indicates life-threatening upper airway obstruction and cardiovascular collapse in anaphylaxis, requiring immediate emergency intervention. Other findings are less critical and manageable with supportive care.

## 심화 해설

Understanding Anaphylaxis as a Life-Threatening Emergency

Anaphylaxis is a severe, systemic hypersensitivity reaction that can be rapidly fatal. The provided protocol and clinical audits emphasize that it is not a single-organ event but a multisystem crisis involving airway, breathing, and circulation. The spectrum ranges from mild cutaneous signs to profound shock, and the nurse’s ability to distinguish between these levels is critical for timely intervention [1].

Analyzing the Correct Answer: Option 3

The finding of stridor with severe respiratory distress and a blood pressure of 70/40 mmHg represents the most critical indicator of anaphylaxis. This combination signifies simultaneous airway compromise and cardiovascular collapse, which are the two primary mechanisms of death in anaphylaxis [1].

- Stridor indicates laryngeal or upper airway edema, a direct consequence of massive mast cell degranulation and mediator release, leading to impending airway obstruction .

- A blood pressure of 70/40 mmHg reflects distributive shock from profound vasodilation and increased vascular permeability. This requires immediate intramuscular epinephrine to prevent progression to cardiac arrest, a documented outcome in severe antibiotic-induced anaphylaxis [1,4].

Why the Other Options Are Less Critical

- Option 1: Localized urticaria and mild itching represent a mild, localized hypersensitivity reaction. While it requires monitoring and reporting, it lacks the multisystem, life-threatening features of airway or circulatory compromise that define anaphylaxis [1].

- Option 2: A blood pressure decrease to 110/70 mmHg with a heart rate of 95 bpm may be an early compensatory response. However, this does not yet meet the threshold for decompensated shock or airway emergency. It warrants close observation but is not the immediate priority over a patient with frank stridor and hypotension .

- Option 4: Nausea, vomiting, abdominal cramping, and diarrhea are common gastrointestinal manifestations of anaphylaxis. While distressing and clinically significant, they are not immediately life-threatening in the absence of concurrent airway or severe circulatory compromise .

Clinical Priority and Immediate Action

The presence of respiratory distress with stridor and hypotension confirms a severe anaphylactic reaction. The established emergency protocol mandates that the nurse’s first and most critical action is to ensure immediate administration of intramuscular epinephrine into the anterolateral thigh, followed by airway stabilization and aggressive intravenous fluid resuscitation [1,2]. Delaying epinephrine in the presence of these signs is associated with poor outcomes, including cardiac arrest [1,4]. The audit of emergency department presentations reinforces that recognition of these multisystem features is the key driver for optimal management and transfer to a higher level of care .References (research sources)

- [1]International Pain and Spine Intervention Society emergency protocols: Allergic and anaphylactic reactions.Research articleSmith CC, Meral RM, Wasserman RA. (2026) · DOI: 10.1016/j.inpm.2026.100796

## 임상 시나리오

Recognizing Critical AnaphylaxisAirway and Circulation as Primary Threats
The most critical indicator is the combination of stridor (signaling laryngeal edema) and severe hypotension (70/40 mmHg). This represents simultaneous airway compromise and cardiovascular collapse, the two primary causes of death.

Immediate administration of intramuscular epinephrine into the anterolateral thigh is the first-line intervention to reverse bronchospasm, vasodilation, and edema. Delays are associated with progression to cardiac arrest.

CautionDo not be distracted by isolated cutaneous or gastrointestinal symptoms. A blood pressure drop alone is not diagnostic; look for respiratory distress or stridor to confirm a life-threatening anaphylactic reaction.

## 핵심 개념

- **Anaphylaxis** — A severe, life-threatening systemic hypersensitivity reaction involving airway, breathing, and circulation, often triggered by medications like antibiotics.
- **Stridor** — A high-pitched, harsh sound during inspiration indicating upper airway obstruction, often from laryngeal edema in anaphylaxis.
- **Distributive Shock** — A type of shock caused by profound vasodilation and increased vascular permeability, leading to hypotension as seen in anaphylaxis.

## 같은 주제 문제

- [A nurse is assessing a 45-year-old patient with a history of mild penicillin sensitivity w…](https://mymerci.kr/pages/nclex_q.php?qn_id=540828)
- [A nurse is caring for a patient experiencing anaphylaxis. Which intervention should the nu…](https://mymerci.kr/pages/nclex_q.php?qn_id=540829)
- [A nurse is caring for a 45-year-old patient in the emergency department who presents with …](https://mymerci.kr/pages/nclex_q.php?qn_id=540830)
- [A nurse is caring for a patient who suddenly develops signs of anaphylaxis after receiving…](https://mymerci.kr/pages/nclex_q.php?qn_id=540831)
- [A nurse is caring for a patient who is experiencing anaphylaxis after receiving a penicill…](https://mymerci.kr/pages/nclex_q.php?qn_id=540832)
- [A nurse is caring for a patient experiencing anaphylaxis. Which nursing action should be t…](https://mymerci.kr/pages/nclex_q.php?qn_id=540833)
- [A nurse is caring for a patient who is experiencing anaphylaxis after receiving a penicill…](https://mymerci.kr/pages/nclex_q.php?qn_id=540834)
- [A nurse is caring for a client who is experiencing anaphylaxis after receiving a penicilli…](https://mymerci.kr/pages/nclex_q.php?qn_id=540835)

---

More free questions: [기출문제](https://mymerci.kr/)

_학습 참고용입니다. 실제 임상은 최신 지침과 소속 기관 프로토콜을 따르세요._