A retrospective analysis of blood gases with two different insulin infusion protocols in patients undergoing cardiovascular surgery

Abstract

Aim: Intraoperative blood glucose concentration is known to be an independent risk factor for morbidity and mortality in patients undergoing cardiovascular surgery. Arterial blood gas analysis is an important investigation to monitor the acid‑base balance and gas exchange in these patients. Hyperglycemia leads to a series of metabolic changes which affect acid‑base balance and serum electrolytes. In this study, we aimed to look into the effect of glycemic control on arterial blood gas parameters, serum electrolytes, and hemoglobin (Hb).

Materials and Methods: We collected data from diabetic patients who underwent cardiovascular surgery between 2010 and 2014. The patients were divided into two groups according to the insulin infusion protocols applied such as with conventional (180–250 mg/dl) (n = 17) (Group 1) and tighter glycemic targets (121–180 mg/dl) (n = 51) (Group 2). We retrospectively analyzed arterial blood gas results taken at different perioperative time points from these patients.

Results: We found that pH HCO₃ and base excess, serum sodium, potassium, calcium, and Hb were similar in both groups.

Conclusion: Our study showed that a tighter intraoperative glycemic control does not affect arterial blood gas parameters, serum electrolytes, or Hb when compared to the conventional glycemic control.

Keywords: Base excess, cardiovascular surgery, diabetes mellitus, electrolytes, perioperative insulin infusion