Purpose: We investigated, first, the safety of use and stability of a plasma substitute-hydroxyethyl starch (HES)-kept in a warming cabinet for a long period, and then the effect on body core temperature of the prewarmed HES in patients during urological surgery.
Methods: In the first part of the study, HES colloid solutions (500 ml per pack; Hespander) were kept in a warming cabinet (40 degrees C) for 3 months and were tested for biological and chemical safety and stability. In the second part of the study, 1000 ml of HES at room temperature (control group; n = 10) or kept in a warming cabinet for a few days (warmed group; n = 10) was infused via a central venous catheter for 30 min in patients undergoing urological surgery under general anesthesia with lumbar epidural anesthesia. Esophageal temperature was monitored as the core temperature. HES fluid temperatures in the pack and at the end of a 1-m intravenous tube connected to the central venous catheter were also measured.
Results: The test of HES products warmed for 3 months passed all inspections performed during the study period. In the warmed group, the pack and intravenous tube temperatures of HES were still high at 15 min after infusion (37.1 degrees +/- 1.5 degrees C [mean +/- SD] and 34.8 degrees +/- 2.2 degrees C, respectively). Core temperature in the warmed group decreased significantly, by 0.34 degrees +/- 0.06 degrees C, but was significantly higher than that in the control group (by 0.84 degrees +/- 0.13 degrees C) after 30 min of the infusion.
Conclusions: The use of HES products kept in a warming cabinet prior to surgery can maintain warm body temperature, easily, safely, and effectively.