Relationship between serum lactate levels and morbidity outcomes in cardiovascular patients after CABG

To evaluate the relationship between postoperative serum lactate levels and outcome in patients undergoing open heart surgery and verify the clinical impact of hyperlactatemia[HL] and low lactemia[LL] during CABG in terms of postoperative morbidity and mortality rate. Descriptive study. Sina Heart Centre [non-university hospital in Isphan, Iran] from fall 2005 to fall 2006. Hundred consecutive patients undergoing cardiac surgery with cardiopulmonary bypass were admitted in the study. Post operative lactate concentration and other metabolic parameters were determined. Evaluation of lactate concentrations, pH values and base excess during the first 24 post operative hours were assessed. Hyperlactatemia was defined as a peak arterial blood lactate concentration exceeding 3 mmol/l. Pre- and intraoperative factors were tested for independent association with the peak arterial lactate concentration and HL. The postoperative outcome of patients with or without hyperlactatemia was compared. We found positive effect of time on lactate and pH levels. On day 1, HL and LL patients had comparable lactate concentrations, which remained significantly higher than those of HL patients. HL is frequent after cardiac surgery. Based on our analyses, postoperative measurement of lactate level appears to be clinically useful. A threshold of 3 mmol/L at ICU admission was able to identify a subpopulation of patients at higher postoperative risk. Sequential determinations identified patients at higher risk for major complication and thus the need for closer surveillance of their therapeutic responses and their metabolic consequences

[ Comparison of bloodless and classic methods of coronary artery bypass grafting in Chamran hospital, Isfahan]

The idea of bloodless medicine and surgery emerged when physicians had to treat patients who defied transfusion for religious reasons [e.g. Jehovah's Witnesses]; moreover, problems in ensuring safe blood supplies, the relevant costs involved, and the post-transfusion complications gave also rise to bloodless method. The aim of this study is to evaluate the reduction of allogenic blood transfusion, postoperative infection and costs in the bloodless group compared to the control. A retrospective comparative study was undertaken for patients undergoing coronary artery bypass grafting [CABG] at Isfahan's Chamran hospital. Two groups of patients undergoing the classic CABG and the Bloodless techniques were compared [100 patients in each group]. For bloodless surgery in addition to considering principles of bloodless medicine and surgery, autologous normovolemic hemodilution was done before operation [1-2 units] and patients were not transfused unless their hemoglobin was 9 gm/dl. Data were analysed by t-test and Chi-square test. Various factors were compared between these two techniques such as units of packed cells [PC] and fresh frozen plasma [FFP] transfused, length of hospital stay, costs and postoperative complications [infection, bleeding, etc.]. In bloodless and classic surgery groups, 76% and 38% did not require PC transfusion, respectively. In addition, we observed a significant difference between FFP transfusion in the bloodless [93%] and classic technique [73%]. No patient in the bloodless group received platelets whereas 2% of the patients in the classic group did. Overall length of hospital stay and ICU stay were less in the bloodless method; hence, the costs were less too. Postoperative infection was less in the bloodless method. These differences were significant. The application of bloodless method for patients undergoing CABG significantly reduces PC and FFP consumption [P=0.001]; therefore, the complications of blood transfusion such as post transfusion HIV, hepatitis, allergic and immunological reactions are decreased. Length of hospital stay and postoperative infections are also reduced which in turn reduce the costs [P=0.001, 0.001 and 0.037, respectively]