Gastrointestinal complications occur in about 2.5% of patients undergoing cardiac surgery, are associated with a high mortality (about 33%), and account for nearly 15% (and perhaps increasing) of all postoperative deaths. The various complications and risk factors are reviewed. Splanchnic ischemia prior to, during, and especially postoperatively appears to be an important cause of these complications. In addition, splanchnic ischemia is hypothesized to be one cause of the systemic inflammatory response syndrome and multiorgan failure that may follow cardiac surgery. The physiology of splanchic perfusion and the effects of cardiac surgery, including cardiopulmonary bypass, on it are reviewed. Finally, possible methods to minimize splanchnic ischemia and reduce the incidence of abdominal complications are discussed.

The development and application of cardiopulmonary bypass (CPB) to permit open heart surgery is considered among the most important clinical advances in medicine during the last half of the 20th century. The birth of CPB for cardiac surgery is attributed to its first successful clinical use by John Gibbon Jr, 51 years ago but its practical clinical use really began in the spring and summer of 1955 when 2 groups led by John Kirklin at the Mayo Clinic and C Walton Lillehei at the University of Minnesota, initiated the routine use of CPB for open heart surgery. However, considerable developments were necessary and preceded the clinical accomplishment of CPB, and much has followed to make it the remarkably safe and effective procedure that it has become today. Many currently practicing cardiac anesthesiologists, cardiac surgeons, and perfusionists are unaware of how brief its history is and how much the practice of CPB has changed during its short existence. The aim of this article is to review this fascinating history and the lessons that can be learned from this review, and to indicate the opportunities that still exist for advancement.

The latest report (fifth report, 2013) of the Interagency Registry for Mechanical Assist Circulatory Support (INTERMACS) reported that since June 2006, 6561 adult patients had received primary implants of left ventricular assist devices (LVADs). 1 Of the devices, 136 were total artificial hearts, 901 were pulsatile devices, and 5515 were continuous flow (CF) devices, of which 5366 involved isolated LVAD implantations. Of the 6561 implants, 4644 were implanted as bridges to heart transplantation (BTT) and 1834 (28%) as destination therapy (DT); however in 2012, 44% of these were implanted for DT. Patients with CF devices had fewer complications and better survival than those with pulsatile devices. Since 2010, essentially 100% of patients stratified to DT received CF devices. Actuarial survival of all patients with CF devices is 80% at 1 year, 70% at 2 years, 59% at 3 years, and 47% at 4 years. Lietz et al 2 reported their later results with the Heart Mate XVE device after the REMATCH trial, and John et al, 3 Loforte et al, 4 and Slaughter et al 5 reported early results with the HeartMate II. More recently, John et al 6 and Adamson et al 7 reported their results with HeartMate II devices implanted in 130 and 55 patients, respectively, between 2005 and 2010. Adverse events included bleeding (requiring red blood cells or reexploration, at time of initial implantation or late gastrointestinal [GI] bleeding [~18%]) in 15% to 36%, infection (local, device and driveline related, or sepsis) in 25% to 50%, neurologic events (ischemic or hemorrhagic strokes or other events) in 10% to 20%, right ventricular (RV) failure in 3% to 5%, and renal failure in 2% to 3%. Device failure or malfunction or thrombosis was infrequent (Table 1). Early deaths were related to multi-organ failure, respiratory failure, RV failure, sepsis, hemorrhage, neurologic events, device thrombosis, and withdrawal. Kirklin and colleagues 40 have summarized the incidence of adverse events during the first 12 months following implantation of CF devices for DT in 1160 patients in the INTERMACS registry (Table 2). Adamson et al 7 did not find significant difference in outcome of the 20 patients over 70 years of age at time of implantation compared with 25 patients under 70 years of age. Kirklin et al presented data that suggest that in lowrisk patients (ie, those without biventricular support, previous cancer, cardiogenic shock, severe RV failure, blood urea nitrogen >50, age >70, and body mass index >32) CF 506788S CVXXX10.

W elcome to the second part of our two-part symposium on complications associated with cardiothoracic and vascular surgery.At the outset, let me again thank Dr. Carol Lake for giving me the honor of editing this issue and for providing advice and support; Ms. Ann-Marie Gailius of Westminster Publications who has served as publications coordinator and has had to work hard to keep us on time and facilitate getting these two issues published, and most especially all of those who contributed articles to these issues.As mentioned in my introduction to the first part, I asked the authors to review the pathophysiology of these complications, emphasizing new data, to suggest anesthetic interventions that