Which is the most relevant knowledge about oxygen administration to a client with COPD?

AIIMS Nagpur NO- 2020

Medical & Surgical Nursing

Medium

Appeared in: AIIMS Nagpur NO- 2020

Explanation

In patients with chronic COPD, the body often adapts to high carbon dioxide levels (hypercapnia).
The primary stimulus to breathe shifts from high CO₂ levels to low oxygen levels (hypoxia), a state known as 'hypoxic drive'.
Administering high concentrations of oxygen can suppress this hypoxic drive, leading to decreased respiratory effort, CO₂ retention, and respiratory failure.
Therefore, low-flow oxygen (1-2 L/min) is used to improve oxygenation to a safe level (e.g., SpO₂ 88-92%) without eliminating the patient's stimulus to breathe.

Option A: A pulse oximeter measures oxygen saturation (SpO₂), which is the percentage of hemoglobin saturated with oxygen. It does not measure blood gases like PaCO₂ or pH.
Option B: A non-rebreather mask delivers a high concentration of oxygen (60-90%), which is dangerous for a stable COPD patient as it can suppress their hypoxic drive.
Option C: This statement incorrectly identifies the location of hypoxia-sensing chemoreceptors. Central chemoreceptors are primarily sensitive to CO₂ and H+ ions.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Oxygen Therapy in Chronic Obstructive Pulmonary Disease (COPD) as background academic context rather than a clinical decision trigger.
Patient Safety: Incorrect oxygen administration in COPD patients is a major safety risk. Nurses must understand the concept of hypoxic drive to prevent iatrogenic respiratory failure. The goal is to 'correct, not perfect' the oxygen levels.
Nursing Assessment: The nurse's role includes titrating oxygen to the lowest effective dose to maintain the target saturation (typically 88-92%), monitoring respiratory rate, level of consciousness, and SpO₂.
What if?: What if the COPD patient presents with acute respiratory distress and severe hypoxemia (e.g., SpO₂ less than 80%)? In this emergency, the immediate priority is to correct life-threatening hypoxemia. Higher concentrations of oxygen may be used initially, but with extreme caution and preparation for potential ventilatory support if the patient's respiratory drive diminishes.

How to Approach the Question

First, identify the core subject: oxygen therapy for a specific patient population, COPD.
Recall the unique pathophysiology of respiratory drive in chronic COPD. Remember that their bodies have adapted to high CO₂.
Evaluate each option based on this specific pathophysiology.
Option A tests knowledge of monitoring devices. Is a pulse oximeter the same as a blood gas analysis? No.
Option B tests knowledge of oxygen delivery devices. Is a high-flow device appropriate for a patient who might retain CO₂? No.
Option C tests knowledge of respiratory physiology. Which chemoreceptors sense oxygen levels? Peripheral, not central.

Concept Tested & Keywords

QTi4x3dzchUmb-g3tCXVo9

E6 Nursing Brunner Adult Health 3SA Vol 1 Part 2 p. 38-40

E6 Nursing Fundamentals Potter Perry 12e Part 5 pp. 7-9, 8-10