Introduction: Diabetic ketoacidosis (DKA) is a complication of diabetes associated with the formation of ketone bodies, including beta-hydroxybutyrate (BHB), which results in ketonemia and metabolic acidosis. The 2024 ADA guidelines (Hyperglycemia Crises in Adults with Diabetes) now recommends using BHB as opposed to anion gap (AG) as part of the resolution criteria, however, there is little clinical data to support this recommendation. Historically, the use of BHB-based monitoring and management of DKA resolution has been variable. Given the theoretical, but not literature-based, benefit of BHB as a resolution criterion, published data is needed to support its use. The purpose of this study was to compare clinical outcomes of monitoring BHB versus AG for DKA resolution.
Methods: This is a retrospective chart review of adults who were admitted with DKA at one of the two study hospitals and managed with continuous IV insulin. One facility checks BHB every 4 hours and uses it as part of the criteria for DKA resolution and transitioning off the insulin drip. At the second institution, BHB is not followed, and AG is used as one of the markers for resolution. The primary outcome is time from the start of continuous IV insulin to administration of SC long-acting insulin. Secondary outcomes are recurrence of DKA during hospital admission and hospital length of stay.
Results: A total of 178 patients were included, 89 in AG group and 89 in the BHB group. There was no difference in DKA severity (p=0.65). Patients were converted to long-acting insulin a median of 10.2 hours sooner with the use of AG compared to BHB, 13.3 (10-18.2) hours vs. 23.5 (17.9-31) hours, (p < 0.01). There was no difference in recurrence of DKA between the BHB and AG group, 4 (4%) and 6 (7%) occurrences respectively (p= 0.75). No difference found in hospital length of stay as the median BHB stay was 98.5 (69.9-143.8) hours compared to 99.6 (61.9-164.3) hours in the AG group (p=1).
Conclusions: Utilization of AG over BHB for DKA resolution led to shorter times on an insulin drip with no increase in DKA recurrence. The importance of a negligible BHB level in defining DKA resolution is questionable and may not be needed.
