Prolonged nasogastric (NG) suction removes large volumes of gastric contents containing:

• Hydrochloric acid (HCl) → loss of H⁺ ions → metabolic alkalosis
• Potassium (K⁺) → hypokalemia
• Sodium (Na⁺) → potential hyponatremia
• Chloride (Cl⁻) → hypochloremia

The resulting picture: Hypokalemic, hypochloremic metabolic alkalosis

Nursing interventions: Monitor electrolytes, replace K⁺ as ordered, accurately measure and record NG output, avoid prolonged suction beyond necessity, assess for signs of hypokalemia (muscle weakness, arrhythmias, abdominal distension).