COMPARISON OF ARTERIAL AND VENOUS-BLOOD GAS VALUES IN THE INITIAL EMERGENCY DEPARTMENT EVALUATION OF PATIENTS WITH DIABETIC-KETOACIDOSIS

Study objective: To determine whether venous blood gas values can repl ace arterial gas Values in the initial emergency department evaluation of patients with suspected diabetic ketoacidosis. Methods: This prosp ective comparison was performed in an adult university teaching hospit al ED. Samples for arterial and venous blood gas analysis were obtaine d during initial ED evaluations. The venous gas samples were collected with samples for other blood tests at the time of intravenous line in sertion. Both arterial and venous samples were obtained before the ini tiation of treatment.Result: Data from 44 episodes of diabetic ketoaci dosis in 38 patients were analyzed. Laboratory findings of those patie nts with diabetic ketoacidosis were as follows (mean+/-SD): arterial p H, 7.20+/-.14; venous pH, 7.17+/-.13; serum glucose, 33.8+/-16 mmol/L (609+/-288 mg/dL); arterial HCO3-, 11.0+/-6.0 mmol; venous HCO3-, 12.8 +/-5.5 mmol/L; serum CO2, 11.8+/-5.0 mmol/L; and anion gap, 26.7+/-7.6 mmol/L. The mean difference between arterial and venous pH values was 0.03 (range 0.0 to 0.11). Arterial and venous pH results (r=.9689) an d arterial and venous HCO3- results (r=.9543) were highly correlated a nd showed a high measure of agreement. Conclusion: Venous blood gas me asurements accurately demonstrate the degree of acidosis of adult ED p atients presenting with diabetic ketoacidosis.