THE BENEFITS OF ACTIVE REWARMING AFTER CARDIAC OPERATIONS - A RANDOMIZED PROSPECTIVE TRIAL

We conducted a prospective, randomized trial of three methods of rewar ming patients after hypothermic cardiopulmonary bypass. Patients under went either coronary artery bypass grafting or first-time valve replac ement and were cooled to 32 degrees C during bypass. No significant di fferences existed among the groups as regards operative or preoperativ e parameters including hemodynamics and blood use. The patients active ly warmed with a convective (Pair Hugger system, 3 hours) or a conduct ive blanket (electric overblanket, 4 hours) reached normothermia more quickly than those warmed with the space blanket (7 hours). This was r eflected in significantly earlier extubation in the former two groups: Pair Hugger system 10.8 +/- 0.6 hours, electric blanket 11.3 +/- 1.0 hours, and space blanket 14.8 +/- 0.8 hours. Patients warmed with the space blanket required a higher dosage of morphine over the first 12 h ours than those warmed with the electric blanket (10.4 vs 6.5 mg; p = 0.004), which may account for some of the differences between these tw o groups. No differences could be demonstrated between the two active blankets. On economic grounds we therefore recommend the reusable elec tric blanket for routine use.