Resistive heating during off-pump coronary bypass surgery

Maintaining normothermia during off-pump coronary artery bypass (OPCAB) surgery is difficult. The purpose of the present study is to determine the effect of the Inditherm Patient Warming System (IPWS) with standard institutional care during OPCAB surgery.

A control cohort of 10 patients undergoing OPCAB surgery received standard conventional therapy. A study cohort of another 10 patients then underwent similar procedures with the additional use of the IPWS. The nasopharyngeal and rectal temperatures of the two groups were compared during the 4-hour study period.

During the 4-hour study period after induction, the Inditherm patients demonstrated significantly improved core body temperatures compared to the control group: lowest rectal temperature: 35.8 +/- 0.4 degrees C vs. 34.8 +/- 0.6 degrees C (p < 0.01) and lowest nasopharyngeal temperature : 35.5 +/- 0.4 degrees C vs. 34.7 +/- 0.5 degrees C (p < 0.01), respectively. The between-group rectal and nasopharyngeal temperature differences reached statistical significance after 70 minutes, 36.2 +/- 0.5 degrees C vs. 35.7 +/- 0.2 degrees C (p < 0.01) and after 60 minutes 35.8 +/- 0.4 degrees C vs. 35.4 +/- 0.1 degrees C (p < 0.01), respectively. At the end, the rectal core temperatures were 36.1 +/- 0.6 degrees C vs. 34.9 +/- 0.6 degrees C (p < 0.01) and the nasopharyngeal temperatures were 35.8 +/- 0.6 degrees C vs. 34.8 +/- 0.5 degrees C (p < 0.01) in the study and the control groups, respectively.

The combination of the IPWS with standard thermal care provides higher core temperatures during OPCAB surgery.