🩺 Nursing Question of the Day

Challenge yourself with one exam-style nursing question every day.

✅ Think carefully • ✅ Choose your answer • ✅ Then scroll down to check the explanation.

🩺 Prolonged Nasogastric (NG) Suction

✅ Answer: (B) Metabolic Alkalosis

📖 What is Nasogastric (NG) Suction?

Nasogastric (NG) = A tube passed through the nose into the stomach.
Suction = Removal of stomach contents using negative pressure.

👉 NG suction is commonly used to relieve gastric distension, intestinal obstruction, or persistent vomiting.

📖 What is Metabolic Alkalosis?

Metabolic = Related to body metabolism and bicarbonate (HCO₃⁻).
Alkalosis = Blood pH becomes too alkaline (pH > 7.45).

👉 It usually occurs due to loss of hydrogen ions (H⁺) or excessive bicarbonate in the body.

🩺 Why is Option (B) Correct?

Gastric secretions contain large amounts of:

• ✔ Hydrochloric acid (HCl)
• ✔ Hydrogen ions (H⁺)
• ✔ Chloride (Cl⁻)

During prolonged NG suction:

• ✔ Large amounts of gastric acid are removed.
• ✔ The body loses H⁺ ions.
• ✔ Blood becomes more alkaline.
• ✔ Metabolic alkalosis develops.

Patients may also develop:

• ✔ Hypochloremia (↓ Chloride)
• ✔ Hypokalemia (↓ Potassium)

👉 Therefore, the expected acid-base imbalance is Metabolic Alkalosis.

❌ Why Other Options Are Wrong?

(A) Metabolic Acidosis
❌ Occurs with diarrhea, renal failure, or diabetic ketoacidosis—not with gastric acid loss.

(C) Respiratory Acidosis
❌ Caused by hypoventilation leading to CO₂ retention, not NG suction.

(D) Respiratory Alkalosis
❌ Results from hyperventilation and excessive CO₂ loss, unrelated to gastric suction.

📝 Effects of Prolonged NG Suction

📌 Exam Tip: In nursing exams, remember the classic association:
Vomiting or prolonged NG suction → Metabolic Alkalosis + Hypochloremia + Hypokalemia.
Conversely, diarrhea commonly causes metabolic acidosis due to loss of bicarbonate.