A patient arterial blood gases (ABG) analysis report shows pH 7.48, CO2 32 mm hg, HCO3 22. What is the possib… - NORCET-7 Mains-2024

NORCET-7 Mains-2024

Medical & Surgical Nursing

Hard

Appeared in: NORCET-7 Mains-2024

Explanation

The patient's pH of 7.48 is above the normal range of 7.35-7.45, indicating alkalosis.
The PaCO₂ of 32 mmHg is below the normal range of 35-45 mmHg. A low PaCO₂ (an acid) leads to alkalosis.
The ROME mnemonic (Respiratory Opposite, Metabolic Equal) confirms the diagnosis. The pH is high and the PaCO₂ is low (opposite direction), indicating a respiratory disorder.
The HCO₃⁻ level of 22 mEq/L is within the normal range (22-26 mEq/L), indicating the condition is uncompensated.

Option A: Respiratory acidosis is incorrect because it is characterized by a low pH (acidosis) and a high PaCO₂, which is the opposite of the patient's findings.
Option B: Metabolic acidosis is incorrect. It involves a low pH and a low HCO₃⁻ level. The patient's pH is high, and HCO₃⁻ is normal.
Option C: Metabolic alkalosis is incorrect. While the pH is high (alkalosis), the primary cause in metabolic alkalosis is a high HCO₃⁻ level, but this patient's HCO₃⁻ is normal.

Visual 1: Flowchart - A step-by-step flowchart for ABG interpretation. It would start with 'Look at the pH', then branch to 'Acidosis' or 'Alkalosis', and then guide the user to check PaCO₂ and HCO₃⁻ to determine the final diagnosis and compensation status.
Visual 2: Diagram - A Tic-Tac-Toe grid method for ABG analysis, showing how to place the pH, PaCO₂, and HCO₃⁻ values into columns (Acid, Normal, Base) to quickly identify the disorder.

Clinical Relevance

Nursing practice connection: Knowing Arterial Blood Gas (ABG) interpretation helps nurses interpret findings accurately and avoid errors in routine assessment, medication administration, and patient teaching.
Respiratory alkalosis is caused by hyperventilation, where the lungs blow off too much CO₂. Common causes a nurse should look for include anxiety, panic attacks, pain, fever, hypoxia, and incorrect mechanical ventilator settings.
Nursing interventions focus on treating the underlying cause. If a patient is hyperventilating due to anxiety, the nurse should provide reassurance, encourage slow breathing, and have the patient breathe into a paper bag (with caution) to rebreathe CO₂.
What if? If the patient's HCO₃⁻ was 18 mEq/L (low), the diagnosis would be partially compensated respiratory alkalosis. This indicates the kidneys have started to excrete bicarbonate to try and lower the pH back to normal.

How to Approach the Question

Step 1: Analyze the pH. Determine if it's acidotic (less than 7.35), alkalotic (greater than 7.45), or normal.
Step 2: Analyze the PaCO₂ (the respiratory component). A value outside the 35-45 mmHg range indicates a respiratory issue.
Step 3: Analyze the HCO₃⁻ (the metabolic component). A value outside the 22-26 mEq/L range indicates a metabolic issue.
Step 4: Match the PaCO₂ or HCO₃⁻ with the pH. Use the ROME mnemonic: Respiratory is Opposite (pH and PaCO₂ move in opposite directions), Metabolic is Equal (pH and HCO₃⁻ move in the same direction).
Step 5: Determine compensation. If the component not causing the problem is moving in the opposite direction to compensate, the condition is compensated. If it's still in the normal range, it's uncompensated.

Concept Tested & Keywords

Qd_e5twYgH7NjZCT-fBJdD