Targeted Temperature Management: Quantifying the Extent of Serum Electrolyte and Blood Glucose Shifts in Postcardiac Arrest Patients

This study aims to quantify the extent of electrolyte (potassium, magnesium, and phosphorus) and blood glucose changes during targeted temperature management (TTM), with insight on electrolyte replacements and insulin administration. This was a 3-year retrospective study of patients who underwent TTM via Arctic Sun. Electrolyte and blood glucose values in addition to electrolyte replacements and insulin administrations were collected before, during, and post-TTM. The primary analysis assessed changes in electrolyte and blood glucose values during and after TTM, and the secondary analysis assessed changes before and during, and before and after TTM. The secondary analysis also incorporated amount of electrolyte replacements and insulin administrations patients received before, during, and post-TTM. Sixty patients were included for analysis. Comparing levels during to after TTM, there was a significant increase in potassium (3.7 [0.7]-4.4 [0.7] mmol/L, p < 0.001) and decrease in blood glucose (192 [135]-134 [55] mg/dL, p = 0.001). Comparing levels before to during TTM, there was a significant decrease in potassium (4.3 [0.7]-3.7 [0.7] mmol/L, p < 0.001) and phosphorus (4.8 [3.2]-3.4 [1.5] mg/dL, p = 0.003). Comparing levels before to after TTM, there was a significant decrease in phosphorus (4.5 [2.9]-3.3 [1.2] mmol/L, p = 0.026) and blood glucose (219 [35]-134 [55] mg/dL, p < 0.001). Patients received on average potassium 102 mEq, magnesium 1.9 g, phosphorus 9 mmol, and insulin 94 units. Potassium significantly decreased during and significantly increased after TTM. Phosphorus significantly decreased during TTM and blood glucose significantly decreased after TTM. There were no significant changes in magnesium during the defined time period.