This article discusses a case of hyperchloremic metabolic acidosis in a 5-month-old infant undergoing ventriculo-peritoneal shunt surgery for hydrocephalus. The patient had been taking acetazolamide, which can cause bicarbonate loss and lead to acidosis. Additionally, the administration of normal saline during surgery further contributed to the acidosis. The article suggests that the use of normal saline in infants should be minimized, and preoperative arterial blood gas analysis may be helpful in identifying potential acidosis in patients taking carbonic anhydrase inhibitors. [Extracted from the article]