Differential Diagnosis
- Single most likely diagnosis
- (e) hyponatremia: The patient has been receiving intravenous 5% dextrose in water in one-half normal saline for 3 days, which can lead to hyponatremia due to the hypotonic solution. Hyponatremia can cause confusion, lethargy, and seizures, which are consistent with the patient's symptoms.
- Other Likely diagnoses
- (a) hypokalemia: Prolonged intravenous administration of fluids without adequate potassium supplementation can lead to hypokalemia. Hypokalemia can cause muscle weakness, fatigue, and cardiac arrhythmias, but it is less likely to cause tonic spasms compared to hyponatremia.
- (c) hypocalcemia: Although less common, hypocalcemia can occur in the postoperative period, especially if the patient has underlying conditions such as vitamin D deficiency or hypoparathyroidism. Hypocalcemia can cause muscle cramps, tetany, and seizures.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- (b) hyperkalemia: Although less likely, hyperkalemia can occur in the postoperative period, especially if the patient has underlying kidney disease or is receiving excessive potassium supplementation. Hyperkalemia can cause cardiac arrhythmias and arrest, making it a critical diagnosis not to miss.
- (d) hypernatremia: Hypernatremia can occur if the patient is receiving excessive sodium or has underlying conditions such as diabetes insipidus. Hypernatremia can cause seizures, coma, and death if not promptly treated.
- Rare diagnoses
- Other electrolyte imbalances, such as hypomagnesemia or hyperphosphatemia, can also occur in the postoperative period, but they are less likely to cause the patient's symptoms. Additionally, other conditions such as sepsis, stroke, or postoperative delirium can also present with similar symptoms, but they are not directly related to the patient's intravenous fluid administration.