Intraoperative temperature control using the Thermogard system during off-pump coronary artery bypass grafting

Normothermia during off-pump coronary bypass (OPCAB) grafting reduces metabolic derangements and contributes to improved clinical outcomes. Thus study examined the feasibility and efficacy of intraoperative temperature control using a novel endovascular heating system during OPCAB.

Thirty-eight consecutive patients undergoing OPCAB were prospectively randomized to receive conventional warming (elevated room temperature, warmed intravenous fluids, warming blanket) or the Thermogard system (Alsius Corp, Irvine, CA). The triple-lumen temperature control Icy catheter (Alsius Corp) was inserted percutaneously into the inferior vena cava through common femoral vein. The catheter was removed after all wounds were closed. Temperature measurements (bladder, nasopharyngeal, and blood) were recorded at 5-minute intervals and compared between groups.

Patient demographics did not significantly differ between groups. The 17 Thermogard patients warmed at a significantly faster rate than the 21 control patients (0.28 degrees vs 0.11 degrees C/h, p = 0.03). Furthermore, Thermogard patients received more bypass grafts (3.4 +/- 0.6 vs 2.6 +/- 0.9, p < 0.001) and less intraoperative fluids (1557.0 +/- 547.7 vs 2012.3 +/- 723.1 mL, p = 0.02) despite longer operative times (150.3 +/- 123.4 vs 108.1 +/- 43.7 min; p = 0.12). All catheters were placed successfully on the first attempt, and there were no device-related complications.

Endovascular warming is safe, simple to use, and obviates the need for uncomfortably warm operating room temperatures. The Thermogard system compared favorably with conventional methods for warming during OPCAB.