In this episode, I’ll discuss using basal insulin in the treatment of diabetic ketoacidosis.
The length of ICU stay for a patient with diabetic ketoacidosis (DKA) is prolonged by the amount of time it takes to transition the patient from IV to subcutaneous insulin. Long-acting insulins can have a role in this transition, potentially leading to a shorter length of stay in the ICU and, by extension, the hospital.
A recent review in the European Journal of Internal Medicine covers the evidence and rationale for long-acting insulin use in patients with DKA.
In a prospective randomized study of 61 patients with DKA, daily subcutaneous injections of insulin glargine (0.25 units/kg body weight) starting within 12 hours of initiation of IV insulin infusion were compared with usual care. The authors sought to determine whether initiation of a long-acting insulin therapy concurrently with IV insulin infusion would decrease the rate of rebound hyperglycemia after discontinuation of the insulin infusion. Capillary blood glucose measurements were obtained up to 12 hours after discontinuation of insulin infusion. Rebound hyperglycemia was defined as a blood glucose level greater than 180 mg/dL.
Overall, 29 subjects in the control group (93.5%) had at least one glucose value above 180 mg/dL during the 12 hour follow-up period. This was significantly greater than the rate of rebound hyperglycemia in the intervention group (10 subjects or 33.3%, P < 0.001). The effect of the intervention was apparent in subjects who presented with diabetic ketoacidosis, after solid organ transplantation, and in patients with other surgical and medical diagnoses. There were three hypoglycemic measurements in two control subjects (68, 62, and 58 mg/dL) and none in the intervention group.
The authors concluded:
Once-daily s.c. insulin glargine administered during i.v. insulin infusion is a safe method for preventing future rebound hyperglycemia, without increased risk of hypoglycemia.
Another group of authors carried out a prospective, randomized, controlled trial comparing the coadministration of insulin glargine and IV insulin (experimental) with IV insulin (standard care control). The primary outcome of time to closure of anion gap (TCAG) was compared between groups using a general linear model (GLM), adjusting for initial anion gap, etiology, and presence of comorbidities. Similarly, the secondary outcome of hospital length of stay (LOS) was adjusted for age, etiology, and hospital site in the GLM.
All patients received IV insulin. Additionally, the experimental group was given SQ insulin glargine within 2 hours of diagnosis. Upon closure of the anion gap, patients in the control group were subsequently transitioned to long-acting insulin. In the study group, IV insulin was discontinued and long-acting subcutaneous insulin was reinstituted 24 hours after initial introduction.
A total of 40 patients were enrolled in this pilot trial. The estimated mean TCAG was 10.2 hours in the experimental group and 11.6 hours in the control group (p = 0.63). The estimated mean hospital LOS was 3.9 days in the experimental group and 4.8 days in the control group (p = 0.66). Incidents of hypoglycemia, rates of ICU admission, and ICU LOS were similar between the groups.
The authors concluded:
Coadministration of glargine in combination with an insulin infusion in the acute management of DKA is feasible. Further study is needed to determine the true efficacy in terms of TCAG and hospital LOS.
The panel of experts that published the Joint British Diabetes Societies guideline for the management of diabetic ketoacidosis recommends continuing a patient’s home dose of long-acting insulin during the initial management of DKA. This recommendation is not based on evidence but rather the assumption that basal insulin in normal daily dose is unlikely to adversely affect the patient’s response to an intravenous insulin infusion and can be expected to facilitate the transition from an intravenous insulin infusion to subcutaneous insulin.
This potentially limits rebound hyperglycemia and ketogenesis when intravenous insulin is stopped and may avoid excess length of stay.
Members of my Hospital Pharmacy Academy have access to my in-depth trainings on DKA/HHS treatment, insulin use in critically ill patients, and insulin dosing for general hospitalized patients. For instant access to these and over 50 other practical clinical pharmacy trainings go to pharmacyjoe.com/academy.
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