NCLEX-RNPhysiological AdaptationHard

A client is found unresponsive with a respiratory rate of 6/min and pinpoint pupils after a suspected opioid overdose. Arterial blood gas results show pH 7.22, PaCO2 68 mmHg, HCO3 24 mEq/L, and PaO2 58 mmHg. Which action should the nurse take first?

  1. AAdminister intravenous sodium bicarbonate
  2. BProvide bag-valve-mask ventilation with supplemental oxygen
  3. CPrepare for endotracheal intubation
  4. DAdminister intravenous naloxone
Show answer & explanation

Correct answer: B. Provide bag-valve-mask ventilation with supplemental oxygen

The ABG shows uncompensated acute respiratory acidosis with hypoxemia from opioid-induced respiratory depression. The immediate priority is to restore ventilation and oxygenation via bag-valve-mask before naloxone takes effect, since airway and breathing take precedence over reversal agents.

Why the other options are wrong

  • A. Sodium bicarbonate does not treat the underlying hypoventilation and is not indicated for acute respiratory acidosis.
  • C. Intubation may ultimately be needed but is not the fastest first step; manual ventilation should begin immediately.
  • D. Naloxone is essential but takes a few minutes to act; ventilation must be supported immediately to prevent hypoxic injury.

Opioid-Induced Respiratory Acidosis

CNS depression from opioids reduces respiratory rate and depth, causing CO2 retention and acute respiratory acidosis with hypoxemia.

  • ABG pattern: low pH, high PaCO2, normal HCO3 (acute, uncompensated)
  • Airway/breathing support precedes naloxone administration
  • Naloxone reverses opioid effect but ventilation must be supported first

Memory trick: Breathe for them before you reverse the drug

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