NORCET 3 - 2022 (Shif…: Which of the following finding suggest to respiratory acidosis?

NORCET 3 - 2022 (Shift-2)

Medical & Surgical Nursing

Hard

Appeared in: NORCET 3 - 2022 (Shift-2)

Explanation

Respiratory acidosis is defined by a low blood pH (less than 7.35) and a high partial pressure of carbon dioxide (PaCO2 greater than 45 mmHg).
The values pH 7.28 and PaCO2 47 mmHg directly match the criteria for respiratory acidosis.
The elevated bicarbonate (HCO3) of 27 mEq/L indicates that the kidneys are attempting to compensate for the acidosis by retaining base, a condition known as partial compensation.
This pattern is caused by hypoventilation, where the lungs fail to eliminate enough CO2, leading to its accumulation in the blood.

Option A: This represents respiratory alkalosis. The pH is high (alkalotic), and the PaCO2 is low, which is the opposite of respiratory acidosis.
Option C: This represents metabolic acidosis. The pH is low (acidotic), but the primary cause is a low bicarbonate (HCO3) level, not an elevated PaCO2.
Option D: This represents compensated metabolic alkalosis. The pH is on the high side of normal, and the bicarbonate (HCO3) is elevated.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Interpretation of Arterial Blood Gas (ABG) results to identify respiratory acidosis as background academic context rather than a clinical decision trigger.
Respiratory acidosis is a critical finding that signals inadequate ventilation. Common causes include COPD exacerbation, opioid overdose, pneumonia, and neuromuscular diseases.
Nurses must prioritize assessing the patient's airway, breathing, and circulation (ABCs). Interventions include encouraging deep breathing, administering bronchodilators, providing supplemental oxygen cautiously, and preparing for potential mechanical ventilation.
What if the patient's values were pH 7.36, PaCO2 50, and HCO3 29? This would indicate fully compensated chronic respiratory acidosis. The pH has returned to the normal range because the kidneys have had enough time to retain sufficient bicarbonate to buffer the high CO2. This is common in stable COPD patients.

How to Approach the Question

First, analyze the pH to determine if the condition is acidosis (less than 7.35) or alkalosis (greater than 7.45).
Next, examine the PaCO2 (the respiratory parameter). If it moves in the opposite direction of the pH (e.g., pH is low, PaCO2 is high), the primary problem is respiratory.
Then, check the HCO3 (the metabolic parameter). If it moves in the same direction as the pH (e.g., pH is low, HCO3 is low), the primary problem is metabolic.
Use the ROME mnemonic (Respiratory Opposite, Metabolic Equal) to quickly confirm the primary disorder.
Finally, assess for compensation. If the non-primary parameter (e.g., HCO3 in a respiratory problem) is abnormal in an attempt to correct the pH, compensation is occurring. If the pH is back in the normal range, it's fully compensated; if it's still abnormal, it's partially compensated.

Concept Tested & Keywords

Concept Tested: Interpretation of Arterial Blood Gas (ABG) results to identify respiratory acidosis.
Stem keywords: respiratory acidosis, finding, ABG values
Lead-in keywords: Which