A 45-year-old patient with asthma is admitted to the emergency department with acute exacerbation. The patient presents with wheezing, chest tightness, and anxiety. Vital signs: BP 130/85 mmHg, HR 100 bpm, RR 30/min, O2 sat 92% on room air. Arterial blood gas results show: pH 7.35, PaCO2 42 mmHg, HCO3- 24 mEq/L, PaO2 70 mmHg. What is the nurse's priority action?
1Administer high-flow oxygen at 15 L/min via non-rebreather mask
2Obtain sputum culture and sensitivity before starting antibiotics
3Educate the family about COPD management and prognosis
4Position the patient in high Fowler's position✓ 정답
해설
Positioning in high Fowler's position and low-flow oxygen improve oxygenation while avoiding CO2 retention in asthma exacerbation. High-flow oxygen can suppress hypoxic drive, and other options are not immediate priorities.
Clinical Judgment
This question assesses priority setting and the principles of oxygen therapy specific to COPD patients. The patient is showing signs of acute respiratory failure (confusion, hypoxemia, hypercapnia) and requires immediate physiological stabilization. The key point is that COPD patients are chronically adapted to high PaCO2, and high-concentration oxygen can suppress their respiratory drive, leading to respiratory depression. Therefore, the priority is an intervention that optimizes the patient's position and improves oxygenation within a safe range (SpO2 88-92%).
Memory Tip:
Remember COPD O2 Low & Slow (COLS). COPD patients need Low-flow, Slow titration oxygen. The goal is "Just enough, not too much."
KR vs US:
In Korea, high-flow oxygen may sometimes be administered empirically even during acute COPD exacerbations, but the NGN/US standard emphasizes the hypoxic respiratory drive theory. On the US NCLEX, any option that unconditionally gives high-concentration oxygen to a COPD patient is treated as an absolute wrong answer.
임상 시나리오
Clinical Practice Guide
The first step in managing a patient with an acute exacerbation of COPD is the ABC (Airway, Breathing, Circulation) assessment. In this patient, Breathing (B) is the clear threat. The nurse's immediate actions are:
1. Positioning: Place the patient in High Fowler's or a forward-leaning seated position to increase the efficiency of accessory breathing muscles.
2. Initiate Oxygen Therapy: Administer low-flow oxygen via nasal cannula or Venturi mask to achieve a target SpO2 of 88-92%. The initial setting is typically 1-2 L/min.
3. Monitoring: Continuously assess respiratory rate, oxygen saturation, and level of consciousness, watching for signs of respiratory depression (decreased respiratory rate, drowsiness).
Caution:
In SATA (Select All That Apply) questions, distinguish between an option that says "Administer oxygen" and one that says "Administer low-flow oxygen." The former may be incorrect, while the latter is correct. Also, patient education or diagnostic tests should be performed after the physiological crisis is resolved.
핵심 개념
Chronic Obstructive Pulmonary Disease — A chronic respiratory disease characterized by airflow limitation. It includes chronic bronchitis and emphysema. The main cause is smoking.
Acute Exacerbation of COPD — COPD symptoms (shortness of breath, cough, sputum) suddenly worsening, requiring additional treatment. Often caused by infection.
Hypoxic Drive — Mechanism by which the primary respiratory drive is regulated by hypoxemia in patients with chronic hypercapnia. High-concentration oxygen can suppress this.
Hypercapnic Respiratory Failure (Type II) — Respiratory failure where carbon dioxide in arterial blood (PaCO2) increases above normal (>45 mmHg). This patient's PaCO2 of 58 mmHg corresponds to this.
High Fowler's Position — Patient sits with the head of the bed raised to 60-90 degrees. This position facilitates diaphragm movement and promotes lung expansion for patients with breathing difficulties.