# 情境 65歲阻塞性睡眠呼吸中止、BMI 38的個案於腹部手術後開始PCA hydromorphone。單位高風險PCA標準包含持續capnography。capnography與pulse oximetry不同的優先監測項目為何?

> source: MyMerci (mymerci.kr)  
> url: https://mymerci.kr/pages/nclex_q.php?qn_id=375173&lang=zh-tw  
> language: zh-TW  
> subject: Adverse Effects/Contraindications/Interactions  
> category: PA

## 題目

情境 65歲阻塞性睡眠呼吸中止、BMI 38的個案於腹部手術後開始PCA hydromorphone。單位高風險PCA標準包含持續capnography。capnography與pulse oximetry不同的優先監測項目為何?

## 選項

1. capnography持續測ETCO2與呼吸速率，pulse oximetry因補充氧氣會延遲SpO2下降，capnography較早偵測鴉片引起的低通氣，護理師於ETCO2上升、RR降低或鎮靜加重時就介入，不等SpO2下降。 **✔ 正確答案**
2. 二氧化碳圖可連續測量呼氣末二氧化碳和呼吸速率，因此可作為鎮靜評估和脈搏血氧飽和度的全方位替代方案，因為它能直接反映病人的通氣狀態，無需進行如Pasero鎮靜量表等額外評估。
3. 二氧化碳圖透過分析呼出氣體來測量血液中的氧氣分壓，對於患有阻塞性睡眠呼吸中止症的肥胖病人，能提供比脈搏血氧飽和度更精確的氧合評估，因此持續性二氧化碳圖監測優於間歇性脈搏血氧檢查。
4. 只要脈搏血氧讀數維持在92%以上，二氧化碳圖就沒有必要，因為補充氧氣可確保足夠的通氣並預防高碳酸血症，使得在接受PCA鴉片類藥物且使用補充氧氣的病人中，持續性ETCO2監測變得多餘，護理師可以僅依賴SpO2趨勢來偵測呼吸抑制。

**正確答案: 1**

## 解析

持續capnography測呼氣末CO2 (ETCO2、正常35~45 mmHg)與呼吸速率。相較pulse oximetry，capnography是鴉片引起低通氣最早期的客觀訊號：ETCO2上升反映通氣不足造成CO2累積，波形變平或消失代表無呼吸。在補充氧氣時即使分鐘通氣量下降、CO2上升，SpO2仍可能維持在90多，故SpO2下降為晚期徵象。高風險PCA病人(睡眠呼吸中止、肥胖、合用鎮靜、未使用過鴉片、高齡、OSA風險評分、既往呼吸事件)推薦監測：(1) 持續capnography包含ETCO2與波形；(2) 持續pulse oximetry；(3) 頻繁的POSS與RR觀察；(4) 每次PCA程式變更時兩位護理師雙人核對。當ETCO2大於50~55 mmHg或基線加10 mmHg、RR

## 深入解析

Capnography在SpO2下降前就捕捉到低通氣。信任ETCO2/波形/RR/鎮靜四要素，不等氧合下降。

## 重要概念

- **capnography (ETCO2)** — 呼氣末CO2分壓，正常35-45 mmHg，即時通氣評估，比SpO2更早
- **pulse oximetry lag** — 補充氧氣使SpO2下降延遲，低通氣發生後才下降
- **high-risk PCA criteria** — OSA、肥胖、合用鎮靜、高齡、opioid-naive、既往呼吸事件

## 相同主題題目

- [A nurse is reviewing the morning lab results for an adult client receiving warfarin for at…](https://mymerci.kr/pages/nclex_q.php?qn_id=360515&lang=zh-tw)
- [A client is admitted to the emergency department after ingesting an unknown amount of acet…](https://mymerci.kr/pages/nclex_q.php?qn_id=362720&lang=zh-tw)
- [A client with chronic heart failure is prescribed metoprolol 25 mg orally twice daily. Bef…](https://mymerci.kr/pages/nclex_q.php?qn_id=362756&lang=zh-tw)
- [A 28-year-old client with type 1 diabetes receives regular insulin 6 units and NPH insulin…](https://mymerci.kr/pages/nclex_q.php?qn_id=362792&lang=zh-tw)
- [A client receives IV vancomycin 1 g every 12 hours for MRSA bacteremia. Before the next do…](https://mymerci.kr/pages/nclex_q.php?qn_id=362833&lang=zh-tw)
- [A client with bipolar disorder has been taking lithium carbonate 600 mg orally three times…](https://mymerci.kr/pages/nclex_q.php?qn_id=362894&lang=zh-tw)
- [An 80-year-old male with heart failure is prescribed digoxin 0.125 mg daily. During mornin…](https://mymerci.kr/pages/nclex_q.php?qn_id=372686&lang=zh-tw)
- [A 38-year-old female with rheumatoid arthritis is being discharged with a new prescription…](https://mymerci.kr/pages/nclex_q.php?qn_id=372687&lang=zh-tw)

## 以其他語言閱讀

- [en](https://mymerci.kr/pages/nclex_q.php?qn_id=375173&lang=en)
- [ko](https://mymerci.kr/pages/nclex_q.php?qn_id=375173&lang=ko)
- [ja](https://mymerci.kr/pages/nclex_q.php?qn_id=375173&lang=ja)
- [zh-TW](https://mymerci.kr/pages/nclex_q.php?qn_id=375173&lang=zh-tw)
- [vi](https://mymerci.kr/pages/nclex_q.php?qn_id=375173&lang=vi)

---

More free questions: [NCLEX-RN 題庫](https://mymerci.kr/pages/nclex_bank.php?lang=zh-tw)

_僅供學習參考。實際臨床請遵循最新指引與所屬機構規範。_