]> 2026-07-31T07:53:12+00:00 WBR0383 0 en Narcotics abuse Methanol intoxication Renal tubular acidosis Acetazolamide intoxication Severe vomiting Severe vomiting typically causes metabolic alkalosis due to loss of gastric. In vomiting, pH would have been > 7.4 with elevated bicarbonate concentration. The patient has a high anion-gap metabolic acidosis. The approach to acid-base disturbances begins with assessment of blood pH. Since the patient's blood pH is 7.26, he is in a state of acidosis. Because acidosis can be metabolic or respiratory, bicarbonate concentration and pCO2 are helpful in distinguishing between the two. In this scenario, the patient has metabolic acidosis, manifesting with low bicarbonate levels. Had this patient had respiratory acidosis, his pCO2 would have been elevated, which is not the case. There are two types of metabolic acidosis: Normal anion gap (hyperchloremic) and high anion gap (normochloremic). To differentiate between them, the equation Anion Gap = Sodium - (Chloride + Bicarbonate) is used. A normal anion-gap ranges btween 8-12 mEq/L. Identification of the type of acid-base abnormality is crucial because it aids in the diagnosis. The patient in this scenario has a high anion gap metabolic acidosis. In this case, anion gap = 140 - (100 + 12) = 30 mEq/L. Among the list of options, only methanol intoxication manifests with a high anion gap metabolic acidosis. Other causes of high anion gap metabolic acidosis can be remembered with the mnemonic KARMEL: Ketoacidosis, Aspirin intoxication, Renal failure, Methanol, Ethanol, Lactic acidosis.<br/> '''Educational Objective:''' Measurement of anion-gap in metabolic acidosis is essential to identify the likely diagnosis. Anion Gap = Sodium - (Chloride + Bicarbonate). A normal anion-gap ranges between 8-12 mEq/L. Common causes of high anion gap metabolic acidosis are KARMEL = Ketoacidosis - Aspirin toxicity – Renal failure – Methanol intoxication – Ethanol intoxication – Lactic acidosis<br/> '''References:''' First Aid 2014 page 328 Physiology B Renal 2020-10-28T00:24:13Z 2459150.5168171 WBR0383