Optimal management of the high risk surgical patient: beta stimulation or beta blockade?

Several groups of investigators have shown that peri-operative goal directed therapy (GDT) may reduce mortality in high-risk surgical patients. GDT usually requires the use of beta-adrenergic agents, however, and these may also carry the risk of cardiac ischemia, especially in patients with ischemic diseases. In this commentary, we will discuss the apparent contradiction between studies showing beneficial effects of GDT in high-risk surgical patients and studies showing the benefit of beta-blockade in high-risk surgery. One of the key differences between both types of studies is that GDT is applied in patients with high risk of postoperative death, excluding patients with cardiac ischemic disease, while studies reporting beneficial effects of beta-blockade have investigated patients with high risk of cardiac ischemia but moderate risk of death related to the surgical procedure itself. It is likely that beta-blockade should be proposed in patients with moderate risk of death, whereas GDT using fluids and inotropic agents should be applied in patients with high risk of peri-operative death. Monitoring central venous oxygen saturation may be useful to individualize therapy, but further studies are required to validate this option.