Ann Thorac Surg 2003;76:1148
© 2003 The Society of Thoracic Surgeons
Invited commentary
Gabriel Aldea, MD
Box 356310, 1959 NE Pacific Street, AA115, Seattle, WA 98195-6310, USA
e-mail: aldea{at}u.washington.edu
Off-pump (OP) CABG has become an accepted routine procedure now offered and practiced by nearly all cardiac surgical centers, but to different degrees and to different subsets of patients. Advances in technologies to displace the heart with minimal hemodynamic compromise and to stabilize the heart and limit ischemia have been rapidly adopted in most centers, with routine use of surface stabilizers and intracoronary shunts. While OP-CABG has absorbed the creative imagination of the surgical community and the resources of industry, cardiopulmonary bypass equipment and techniques used by the same surgical teams have changed little in the past 20 years. Centrifugal pumps, membrane oxygentors, more precise (individualized) anticoagulation protocol, routine evaluation of the ascending aorta with epiaortic scanning, less traumatic aortic clamps, elimination of partial occlusion clamping, improved myocardial protection cardioplegic techniques and composition, heparin-bonded circuits, elimination of cardiotomy suction, minimal prime volumes with autologous priming have all made cardiopulmonary bypass safer and more effective. Despite these dramatic improvements and safer perfusions options, these changes have been implemented piece meal as isolated concepts rather than routinely and systematically, with huge variability between surgical centers. Biocompatible heparin bonded circuits (HBC) have been demonstrated to blunt much of the activation of platelets, coagulation, and inflammatory systems, especially when cardiotomy suction is eliminated and lower anticoagulation protocols are utilized. When properly used, these techniques have been demonstrated to be safe and lower transfusion requirement, postoperative complications and hospital stay and therefore cost. Despite this, HBC are used in less than 20% of centers in the US with only a fraction using lower anticoagulation protocols.
Doctor Øvrum’s group, among others, has been on the forefront of developing and evaluation HBC and lower anticoagulation protocols. In this issue of The Annals, Dr Øvrum and colleagues have set a new gold standard for on-pump CABG patients. In a series of 2500 consecutive patients undergoing isolated CABG over a 4 year period, this group posted spectacular results, with a very low mortality and morbidity, short hospital stay, a transfusion of less than 5% and median time to extubation of 1.5 hours obtained by a thoughtful and systematic application of the best CPB techniques and strategies, and by adopting advanced protocols to abbreviate hospital stay. One can question if these patients were healthier and more unique compared with patients presenting for CABG elsewhere (87.5% were elective, and 80% had hematocrits high enough to allow prebypass autologous blood removal) and argue that there is no comparison group of OP-CABG patients to intellectually support the title of "better than off-pump?." That however would miss the importance, strength and clarity of the message. The use of HBC with the techniques described is safe, simple, reproducible, economical and dramatically improve clinical outcomes in all patients undergoing cardiac surgery with cardiopulmonary bypass.
This approach and outstanding results mirror our own experience and that of others and does not take anything away from advances in OP-CABG that are equally evident and clear. It sets a new standard whenever cardiopulmonary bypass is used and for future comparisons with both OP-CABG and percutaneous revascularization. By expanding choices and improving results it may help surgeons select the CABG strategy best suited for each individual patient.
