M. Mazer and E. Chen (2009). Is subcutaneous administration of rapid-acting insulin as effective as intravenous insulin for treating diabetic ketoacidosis?. Annals of emergency medicine, 53(2), 259-63. https://doi.org/10.1016/j.annemergmed.2008.07.023

PubMed 19177639

[Abstract]
To determine whether intermittent subcutaneous administration of rapid-acting insulin is as effective as intravenous infusion of regular insulin for treating uncomplicated diabetic ketoacidosis, we performed a MEDLINE, EMBASE, and Cochrane Library search, using the key words "subcutaneous insulin AND intravenous insulin AND diabetic ketoacidosis; LIMIT humans and English." We also searched the references in these articles for additional studies. This search yielded a total of 35 articles, 4 of which directly addressed the question at hand. According to this review of the available evidence; subcutaneous administration of rapid-acting insulin analogs such as lispro is as effective and safe as intravenous infusion of regular insulin for the management of uncomplicated diabetic ketoacidosis. In addition, use of insulin analogs may confer an overall cost savings, obviating the need for infusion pumps and ICU admissions in certain institutions. Therefore, it would be safe and effective to use subcutaneously administered rapid-acting insulin analogues instead of intravenous regular insulin infusions for patients with uncomplicated diabetic ketoacidosis.