Rapid rise in insulin requirements of inpatients with covid-19 given dexamethasone: Adaptations of the national guidelines to local needs

ABSTRACT

Background: Hyperglycaemia during admission with covid- 19 is associated with worse outcomes. Dexamethasone is used in severe covid-19. The national guidance suggests using prn quick acting insulin followed by twice daily intermediate acting insulin (0.3 units/kg) if blood glucose continues >12 mmol/L. Aim: To evaluate insulin requirements in inpatients with covid-19 and treated with steroids. Methods: Four rapid iterative quality improvement cycles evaluated the strategy for initiating insulin for patients with persistent hyperglycaemia (>11 mmol/L) and given steroids in an inner city teaching hospital trust. We identified consecutive referrals to the inpatient diabetes team. Exclusions include <7 days of steroids course, admission to intensive care or intravenous insulin. Electronic records were reviewed. Results are mean±SD. Results: Thirty-two referrals identified (63% male), type 2 diabetes 78%/22% no history of diabetes, 66 ± 11 years old, weight 90 ± 24 kg, HbA1c 75 ± 2.8 mmol/mol. covid-4C score 11/21 indicating high-risk patients. Seven days cumulative dexamethasone (or equivalent) dose was 48±23 mg. Admission glucose was 11.5 ± 5.7 mmol/L peaking on day 2 of steroids course (15.2 ± 4.4 mmol/L) and declining to nadir of 11.7 ± 4.2 mmol/L on day 6. Total daily insulin requirements rose rapidly from 0.07 ± 0.18 units/kg (day 1) to a peak of 0.72 ± 0.8 units/kg (day 4) and nadir of 0.64±0.7 units/kg (day 7). Conclusions: We found insulin requirements suggested in the national guidance to be a conservative estimate. In our cohort it is more than doubled in a short period of time requiring rapid titration. Learnings from this work informed the rapid adaptation of the local guidance by advocating early introduction of scheduled intermediate acting insulin when pre-steroids blood glucose is ≥11 mmol/L.