Acidosis: The Prime Determinant of Depressed Sensorium in Diabetic Ketoacidosis

Abstract

OBJECTIVE — The etiology of altered sensorium in diabetic ketoacidosis (DKA) remains unclear. Therefore, we sought to determine the origin of depressed consciousness in DKA. RESEARCH DESIGN AND METHODS — We analyzed retrospectively clinical and biochemical data of DKA patients admitted in a community teaching hospital. RESULTS — We recorded 216 cases, 21 % of which occurred in subjects with type 2 diabetes. Mean serum osmolality and pH were 304 31.6 mOsm/kg and 7.14 0.15, respectively. Acidosis emerged as the prime determinant of altered sensorium, but hyperosmolarity played a synergistic role in patients with severe acidosis to precipitate depressed sensorium (odds ratio 2.87). Combination of severe acidosis and hyperosmolarity predicted altered consciousness with 61 % sensitivity and 87 % specificity. Mortality occurred in 0.9 % of the cases. CONCLUSIONS — Acidosis was independently associated with altered sensorium, but hy-perosmolarity and serum “ketone ” levels were not. Combination of hyperosmolarity and acidosis predicted altered sensorium with good sensitivity and specificity. Diabetes Care 33:1837–1839, 2010 D iabetic ketoacidosis (DKA) is fre-quently associated with alteredmental status, which is correlated with the severity of the disease and prog-nosis (1). However, the etiology of de-pressed sensorium in DKA remains uncertain and controversial (2,3). Puta-tive factors in the pathogenesis of diabetic ketoacidotic coma include cerebral hypo-perfusion due to circulatory collapse and cerebral thrombosis (4), reduced cerebral glucose and oxygen utilization (1,5), aci-dosis (6,7), hyperosmolarity (8,9), and direct toxic effect of ketone bodies (2). Cerebral edema remains an important precipitant of altered consciousness in DKA, especially in children. Different studies have yielded con-flicting results regarding the role of these etiologic factors in the pathogenesis of al-tered mentation in patients with DKA. Hence, the origin of clouded sensorium in DKA remains to be fully elucidated. We undertook to study the etiology of de-pressed consciousness in patients admit-ted with DKA at the Regional Medica