TY - JOUR
T1 - Diagnosis of mixed acid-base disorders in diabetic ketoacidosis
AU - Paulson, W. D.
AU - Gadallah, M. F.
PY - 1993
Y1 - 1993
N2 - In diabetic ketoacidosis, a mixed acid-base disorder is suggested when the anion gap increase (ΔAG) does not equal the bicarbonate decrease (ΔHCO3), or when the ΔAG/ΔHCO3 ratio does not equal 1.0. It is widely assumed that ΔAG/ΔHCO3 is significantly different from 1.0 when it is less than 0.8 or greater than 1.2. The validity of these ratio limits were examined by analyzing a normal control group of 68 subjects and 27 diabetic ketoacidosis admissions that had no evidence of mixed disorders. In the 27 ketoacidosis admissions, regression analysis showed that ΔAG was predicted to equal ΔHCO3, as expected in pure anion gap acidosis: ΔAG = 1.0ΔHCO3 (r = 0.744, p < 0.001). It was found that ΔAG is significantly different from ΔHCO3 when they differ by more than 8 mEq/L, and equivalently, ΔAG/ΔHCO3 is significantly different from 1.0 when it is less than (1.0 - 8/ΔHCO3) or greater than (1.0 + 8/ΔHCO3). These criteria from regression analysis suggested that 4% of the 27 pure anion gap acidoses, and 3% of the control group, had mixed disorders. In contrast, the ratio limits of 0.8 and 1.2 suggested 56% of the pure anion gap acidoses, and 94% of the control group, had mixed disorders. It was concluded that mixed disorders are overdiagnosed by the ratio limits of 0.8 and 1.2. Mixed disorders are more accurately detected by noting whether ΔAG and ΔHCO3 differ by more than 8 mEq/L.
AB - In diabetic ketoacidosis, a mixed acid-base disorder is suggested when the anion gap increase (ΔAG) does not equal the bicarbonate decrease (ΔHCO3), or when the ΔAG/ΔHCO3 ratio does not equal 1.0. It is widely assumed that ΔAG/ΔHCO3 is significantly different from 1.0 when it is less than 0.8 or greater than 1.2. The validity of these ratio limits were examined by analyzing a normal control group of 68 subjects and 27 diabetic ketoacidosis admissions that had no evidence of mixed disorders. In the 27 ketoacidosis admissions, regression analysis showed that ΔAG was predicted to equal ΔHCO3, as expected in pure anion gap acidosis: ΔAG = 1.0ΔHCO3 (r = 0.744, p < 0.001). It was found that ΔAG is significantly different from ΔHCO3 when they differ by more than 8 mEq/L, and equivalently, ΔAG/ΔHCO3 is significantly different from 1.0 when it is less than (1.0 - 8/ΔHCO3) or greater than (1.0 + 8/ΔHCO3). These criteria from regression analysis suggested that 4% of the 27 pure anion gap acidoses, and 3% of the control group, had mixed disorders. In contrast, the ratio limits of 0.8 and 1.2 suggested 56% of the pure anion gap acidoses, and 94% of the control group, had mixed disorders. It was concluded that mixed disorders are overdiagnosed by the ratio limits of 0.8 and 1.2. Mixed disorders are more accurately detected by noting whether ΔAG and ΔHCO3 differ by more than 8 mEq/L.
KW - Acid-base imbalance
KW - Anion gap
KW - Diabetic acidosis
KW - Metabolic acidosis
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U2 - 10.1097/00000441-199311000-00004
DO - 10.1097/00000441-199311000-00004
M3 - Article
C2 - 8238083
AN - SCOPUS:0027421501
SN - 0002-9629
VL - 306
SP - 295
EP - 300
JO - American Journal of the Medical Sciences
JF - American Journal of the Medical Sciences
IS - 5
ER -