Improved outcome for seriously ill open heart surgery patients: focus on reoperation and endocarditis.
Although routine cardiac surgical procedures are now performed with low rates of mortality and relatively low rates of morbidity, certain categories of patients continue to present a major challenge. Patients who have reoperations and those with active infective endocarditis represent high-risk categories. The pathophysiologic mechanisms involved in such patients include impaired left ventricular function and low cardiac output, sepsis, endotoxemia, and gut permeability, and impaired hemostasis. Although these mechanisms are distinct, they do interrelate. Low cardiac output and imperfect systemic perfusion during and after cardiopulmonary bypass are known to induce splanchnic ischemia with altered permeability of the gut mucosal barrier to gut contents, including endotoxin. The systemic inflammatory response, triggered by contact activation of factor XII, produces functional disturbance in vital organs, notably the brain and lung. In addition, factor XII activation induces disordered hemostasis, which is related to increased fibrinolysis and a possible disturbance in platelet function. Measures to modify these mechanisms and improve outcome in high-risk patients include pulsatile perfusion during cardiopulmonary bypass and aprotinin therapy to modify the inflammatory response and prevent the disorder in hemostasis. Clinical experience with high-dose aprotinin therapy in patients who have reoperations and active endocarditis has demonstrated a very high level of efficacy in reducing blood loss and blood/blood product transfusion requirements. The potential role of aprotinin in stabilizing the microcirculation and modifying the systemic inflammatory response requires further study and may prove to be a major contribution to improved outcome in high-risk patients.
Taylor
K M
KM
Department of Cardiac Surgery, Royal Postgraduate Medical School, Hammersmith Hospital, London, England.
D007611:Aprotinin / Q000627:therapeutic use; D006348:Cardiac Surgical Procedures; D016638:Critical Illness; D004696:Endocarditis / Q000209:etiology / Q000503:physiopathology*; D006439:Hemodynamics; D006487:Hemostasis / Q000187:drug effects; D006801:Humans; D011183:Postoperative Complications; D012086:Reoperation; D012307:Risk Factors
D007611:Aprotinin