Insulins and DKA came up in conference last week, but we didn’t discuss the use of subcutaneous insulin in DKA. SQ insulin is a potential alternative to IV therapy in mild to moderate DKA, and I think there is still a lot of variability in provider familiarity and comfort with this treatment approach.
Why use subcutaneous fast-acting insulin?
Giving SQ insulin may be easier than giving it IV, and could simplify treatment of what tends to be a resource-intensive condition. DKA requires frequent monitoring/testing, considerable nursing time, and frequently lands patients in the ICU, which is an expensive disposition.
There is reasonable evidence that SQ is a feasible alternative to IV insulin in mild to moderate severity DKA. A Cochrane review (2016) showed equivalent safety, time to resolution of DKA, and hospital length of stay for SQ insulin compared to IV across several small RCTs.1 Other studies have shown reductions in ICU utilization with SQ protocol in both adults and children.2,3 Last year, a study showed reductions in ED LOS using a SQ protocol.4
In our own departments, I find it intuitive that SQ insulin could reduce burden for our critical care areas (fewer patients needing resus?) and our nurses, and potentially decrease time to treatment initiation (e.g., no pump, potentially fewer IVs). However, it is worth acknowledging that lab frequency isn’t necessarily relieved with a SQ protocol, and SQ insulin needs to be manually given every 2 hours.
Another major consideration is the degree of buy-in and agreement that would be desirable from upstairs departments should SQ protocols become more ubiquitous. DKA patients get admitted, so we should be taking our IM and ICU colleagues’ preferences and needs into account.
The bottom line is that clinically, it probably doesn’t matter how DKA patients are getting their insulin, as long as we’re safely monitoring, volume-resuscitating, and potassium-repleting; SQ could streamline the systems side of the equation, though it isn’t a perfect solution.
Who is a candidate for a subcutaneous insulin protocol?
SQ protocols have been studied in and implemented for patients with mild to moderate DKA (ADA Classification). Generally speaking, that’s any DKA patient with a pH above 7, bicarb of 10 or above, and reasonable mental status. Currently, I’d hesitate to start SQ treatment in a patient on the severe end of a moderate DKA diagnosis, but anticipate my SQ treatment threshold will become lower as I become more facile with these protocols.
How do you do it?
Instead of starting an insulin infusion, you dose SQ insulin every 2 hours and can titrate based on FSBG. Fluid choice and potassium administration don’t need to change with SQ management. Here are a few protocols for you to check out:
SQuID (U of Cincinnati) *note 0.45% NS would be an unusual fluid choice unless hypernatremic
Don’t forget about early SQ basal insulin!
In addition to fast-acting SQ insulin, it is also reasonable to give basal subcutaneous insulin early, when you start DKA treatment. Early basal insulin isn’t yet universally formalized in guidelines or protocols in the United States, but has been shown to reduce rebound hyperglycemia, reduce time to DKA resolution, reduce IV insulin requirements, and reduce length of stay without increasing hypoglycemic or hypokalemic events.5 You can restart home basal insulin or give 0.25 units/kg basal insulin for new treatments in patients with normal renal function.
- Andrade‐Castellanos CA, Colunga‐Lozano LE, Delgado‐Figueroa N, Gonzalez‐Padilla DA. Subcutaneous rapid‐acting insulin analogues for diabetic ketoacidosis. Cochrane Database of Systematic Reviews 2016, Issue 1. Art. No.: CD011281. DOI: 10.1002/14651858.CD011281.pub2. Accessed 12 May 2024.
- Umpierrez GE, Latif K, Stoever J, Cuervo R, Park L, Freire AX, E Kitabchi A. Efficacy of subcutaneous insulin lispro versus continuous intravenous regular insulin for the treatment of patients with diabetic ketoacidosis. Am J Med. 2004 Sep 1;117(5):291-6. doi: 10.1016/j.amjmed.2004.05.010. PMID: 15336577.
- Razavi Z, Maher S, Fredmal J. Comparison of subcutaneous insulin aspart and intravenous regular insulin for the treatment of mild and moderate diabetic ketoacidosis in pediatric patients. Endocrine. 2018 Aug;61(2):267-274. doi: 10.1007/s12020-018-1635-z. Epub 2018 May 24. PMID: 29797212.
- Griffey RT, Schneider RM, Girardi M, Yeary J, McCammon C, Frawley L, Ancona R, Cruz-Bravo P. The SQuID protocol (subcutaneous insulin in diabetic ketoacidosis): Impacts on ED operational metrics. Acad Emerg Med. 2023 Aug;30(8):800-808. doi: 10.1111/acem.14685. Epub 2023 Feb 27. PMID: 36775281.
- Gilbert BW, Murray DS, Cox TR, He J, Wenski AM, Qualls KE. What are we waiting for? A review of early basal insulin therapy in diabetic ketoacidosis management. Am J Emerg Med. 2023 Oct;72:147-150. doi: 10.1016/j.ajem.2023.07.049. Epub 2023 Jul 30. PMID: 37531711.
