Abstract
BACKGROUND: The use of insulin bolus at the initiation of continuous intravenous insulin infusion (CII) in hyperglycemic emergencies remains controversial, with limited real-world data in patients with severe presentations. Although some guidelines discourage its routine use, there are many variations in clinical practice and its clinical benefit remains uncertain. METHODS: We conducted a retrospective single-center study using propensity score matching to evaluate the impact of rapid bolus insulin administration at the start of CII in diabetic patients with hyperglycemic emergencies. Among 99 patients treated with CII between April 2010 and December 2024, 21 pairs of patients with and without bolus insulin were matched based on clinical and biochemical severity indicators. Clinical outcomes and glycemic control parameters were compared using Wilcoxon rank-sum and chi-square tests. RESULTS: Rapid bolus insulin administration did not improve the length of hospital period, time to CII withdrawal, or glycemic control in the short and long term. However, the bolus group showed significantly higher insulin use during the treatment and greater fluctuations in serum potassium levels (Δpotassium: 1.2 (0.8-1.9) vs. 1.0 (0.4-1.3) mmol/L, p = 0.049). No significant differences were observed in rates of hypokalemia, mortality, or other adverse events. CONCLUSION: Rapid bolus insulin administration at the initiation of CII was not associated with the improvement of clinical outcomes or faster glycemic recovery. It was associated with the increase of insulin use and potassium variability. These findings suggest that a more conservative approach without an initial bolus of insulin is sufficient in managing hyperglycemic emergencies. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13340-026-00892-8.