In this episode, I’ll discuss how 5 units of insulin works for hyperkalemia instead of 10.
While insulin is an effective way to lower potassium during hyperkalemia treatment, hypoglycemia may result even if dextrose is given along with insulin treatment. This is especially likely in patients with renal dysfunction as the effects of insulin may be prolonged.
4 years ago in episode 234 I discussed a retrospective review that suggested that 5 units of insulin would lower potassium just as well as 10 units, with less hypoglycemia.
More recently in episode 612 I discussed a meta-analysis published in the journal Pharmacotherapy looking at Reduced Alternative Insulin Dosing in Hyperkalemia.
10 studies, all retrospective cohorts, involving more than 3400 patients were analyzed and the authors found that compared with 10 units of insulin, lower insulin dosing strategies had an odds ratio for hypoglycemia of 0.55 and for severe hypoglycemia of 0.41.
At the same time, there was no difference in potassium reduction between the different doses of insulin used.
However, a single-center quasi-experimental study of the implementation of a lower-dose protocol was just published in AJHP with different results.
The authors revised their hyperkalemia treatment pathway to allow for a reduced-dose option (5 units of insulin) for patients with end-stage renal disease. They then evaluated the impact of the revision by assessing rates of hypoglycemia during the 6 months before and after implementation of the revised pathway.
The primary endpoint was prevalence of hypoglycemia, defined as a blood glucose level of less than or equal to 70 mg/dL.
The authors found:
There was no statistically significant difference in the occurrence of hypoglycemia when comparing the pre- and postimplementation groups (36 [17.7%] patients vs 34 [18.7%] patients; P = 0.7924). The postimplementation group had a statistically significant lower reduction in potassium levels after treatment than the preimplementation group (mean [interquartile range], –0.9 [–1.3, –0.5] mEq/L vs –0.6 [–1.2, –0.2] mEq/L; P = 0.0095). Baseline potassium levels were similar between the groups.
A post hoc analysis was done to account for possible confounders and the only variable that was associated with hypoglycemia was pretreatment glucose level.
In both the pre and post-implementation group, the median pretreatment glucose level in patients who experienced hypoglycemia was about 122 mg/dL as compared to a median of 176 mg/dL in the pre- and 163 mg/dL in the post-implementation group who did not experience hypoglycemia.
To access my free download area with 20 different resources to help you in your practice, go to pharmacyjoe.com/free.
If you like this post, check out my book – A Pharmacist’s Guide to Inpatient Medical Emergencies: How to respond to code blue, rapid response calls, and other medical emergencies.