The nurse identifies that the condition in which arterial blood gas analysis showing pH of 7 and plasma bicarbonate value of 19 mmol/L is ___.

1. A

   Respiratory acidosis

2. B

   Respiratory alkalosis

3. C

   Metabolic acidosis

4. D

   Metabolic alkalosis

Appeared in: GMCH Nursing Officer-2025

Explanation

• The patient's pH of 7.0 is below the normal range of 7.35-7.45, indicating a state of acidosis.
• The plasma bicarbonate (HCO₃⁻) level of 19 mmol/L is below the normal range of 22-28 mEq/L.
• In metabolic acidosis, both the pH and the bicarbonate level are decreased, as the primary problem is a loss of bicarbonate or an accumulation of metabolic acids.
• The ROME mnemonic (Respiratory Opposite, Metabolic Equal) confirms this: the pH is low and the HCO₃⁻ is low (moving in the same/equal direction), pointing to a metabolic cause.

Why Other Options Were Wrong

• Option A: Respiratory acidosis is characterized by a low pH and a high PaCO₂ due to hypoventilation. The question provides a low bicarbonate level, not a high PaCO₂.
• Option B: Respiratory alkalosis involves a high pH (above 7.45) and a low PaCO₂ due to hyperventilation. The patient's pH is low, not high.
• Option D: Metabolic alkalosis is defined by a high pH (above 7.45) and a high bicarbonate level (above 28 mEq/L). The patient's values are low for both.

Related Visual

• Visual 1: Flowchart - A step-by-step flowchart for ABG interpretation. It would start with 'Check pH', then branch to 'Acidosis' or 'Alkalosis', and then further branch based on PaCO₂ and HCO₃⁻ levels to identify the specific imbalance.
• Visual 2: Diagram - A diagram illustrating the ROME (Respiratory Opposite, Metabolic Equal) mnemonic with arrows showing the directional relationship between pH, PaCO₂, and HCO₃⁻ for each of the four primary acid-base disorders.

Clinical Relevance

• Nursing practice connection: Knowing Interpretation of Arterial Blood Gas (ABG) results to diagnose acid-base imbalances helps nurses interpret findings accurately and avoid errors in routine assessment, medication administration, and patient teaching.
• Nurses are often the first to recognize signs of acid-base imbalance (e.g., changes in respiration, level of consciousness) and are responsible for monitoring ABG results.
• For a patient with metabolic acidosis, key nursing interventions include monitoring vital signs, assessing respiratory status for compensatory hyperventilation (Kussmaul respirations), administering IV fluids and electrolytes as ordered, and treating the underlying cause (e.g., insulin for DKA, dialysis for renal failure).
• A pH of 7.0 is a critical value indicating severe acidosis, which can lead to decreased myocardial contractility, arrhythmias, and impaired cellular function. This requires immediate medical attention.

How to Approach the Question

• Step 1: Analyze the pH. Determine if it's acidosis (less than 7.35), alkalosis (greater than 7.45), or normal.
• Step 2: Analyze the PaCO₂ (the respiratory parameter). A normal value is 35-45 mmHg. If it's abnormal, see if it moves in the opposite direction of the pH (indicating a respiratory problem).
• Step 3: Analyze the HCO₃⁻ (the metabolic parameter). A normal value is 22-28 mEq/L. If it's abnormal, see if it moves in the same (equal) direction as the pH (indicating a metabolic problem).
• Step 4: Apply the ROME mnemonic (Respiratory Opposite, Metabolic Equal) to confirm the primary disorder.
• Step 5: In this question, the pH is low (Acidosis) and the HCO₃⁻ is low. Since they move in the same direction, it is a Metabolic problem. Therefore, the diagnosis is Metabolic Acidosis.

Concept Tested & Keywords

• Concept Tested: Interpretation of Arterial Blood Gas (ABG) results to diagnose acid-base imbalances.
• Stem keywords: arterial blood gas analysis, pH 7, plasma bicarbonate 19 mmol/L
• Lead-in keywords: identifies that the condition
• Negative lead-in flag: false

Question ID

QPrbQIEXwdxhgogMTjfKA4

Copy ID