The Mega Acer Kit® (MAK) is a newly designed heated and humidified breathing circuit that warms fluid passing through the circuit lumen. In this study, we investigated the system's efficacy for the perioperative prevention of hypothermia and fluid warming.

Ninety patients undergoing spinal surgery were enrolled in this study and randomly assigned to 3 groups based on the fluid warming device used: no fluid warming system (Group C, n = 30), via a Standard Ranger (Group R, n = 30), or via the MAK (Group M, n = 30). Distal esophageal temperatures (Teso) and infusion fluid temperature (TF) were recorded at 15 min intervals for duration of 180 min during surgery. If Teso was < 35.0℃, a forced-air convective warming device was used.

Final Teso values were 34.8 ± 0.3℃, 35.1 ± 0.1℃, and 35.8 ± 0.3℃ in groups C, R, and M, respectively (P < 0.01). Teso was significantly higher in group M when compared with that in groups C and R throughout the study period (P < 0.05). The number of patients requiring a forced-air convective warming device was significantly lower in group M (n = 0) when compared with that in groups R (n = 17) and C (n = 30) (P < 0.05). The final infusion fluid temperature was higher in group M when compared with that in groups C and R throughout the study period (35.4 ± 1.0 vs. 23.0 ± 0.3 and 32.8 ± 0.6℃; P < 0.01).

The MAK is more effective for preventing hypothermia and for warming fluid than the Standard Ranger.