1.
Different dose regimes and administration methods of tranexamic acid in cardiac surgery: a meta-analysis of randomized trials
Guo J, Gao X, Ma Y, Lv H, Hu W, Zhang S, Ji H, Wang G, Shi J
BMC anesthesiology. 2019;19(1):129
Abstract
BACKGROUND The efficacy of tranexamic acid (TXA) to reduce perioperative blood loss and allogeneic blood transfusion in cardiac surgeries has been proved in previous studies, but its adverse effects especially seizure has always been a problem of concern. This meta-analysis aims to provide information on the optimal dosage and delivery method which is effective with the least adverse outcomes. METHODS We searched Cochrane Central Register of Controlled Trials, MEDLINE and EMBASE for all relevant articles published before 2018/12/31. Inclusion criteria were adult patients undergoing elective heart surgeries, and only randomized control trials comparing TXA with placebo were considered. Two authors independently assessed trial quality and extracted relevant data. RESULTS We included 49 studies with 10,591 patients into analysis. TXA significantly reduced transfusion rate (RR 0.71, 95% CI 0.65 to 0.78, P<0.00001). The overall transfusion rate was 35%(1573/4477) for patients using TXA and 49%(2190/4408) for patients in the control group. Peri-operative blood loss (MD - 246.98 ml, 95% CI - 287.89 to - 206.06 ml, P<0.00001) and re-operation rate (RR 0.62, 95% CI 0.49 to 0.79, P<0.0001) were also reduced significantly. TXA usage did not increase risk of mortality, myocardial infarction, stroke, pulmonary embolism and renal dysfunction, but was associated with a significantly increase in seizure attack (RR 3.21, 95% CI 1.04 to 9.90, P = 0.04).The overall rate of seizure attack was 0.62%(21/3378) for patients using TXA and 0.15%(5/3406) for patients in the control group. In subgroup analysis, TXA was effective for both on-pump and off-pump surgeries. Topical application didn't reduce the need for transfusion requirement, while intravenous delivery no matter as bolus injection alone or bolus plus continuous infusion were effective. Intravenous high-dose TXA didn't further decrease transfusion rate compared with low-dose regimen, and increased the risk of seizure by 4.83 times. No patients in the low-dose group had seizure attack. CONCLUSIONS TXA was effective in reducing transfusion requirement in all kinds of cardiac surgeries. Low-dose intravenous infusion was the most preferable delivery method which was as effective as high-dose regimen in reducing transfusion rate without increasing the risk of seizure.
2.
Effects of intraoperative autologous blood donation and tepid temperature cardiopulmonary bypass on blood system
Zhang S, Yao S
Journal of Tongji Medical University. 2000;20((2):):151-3.
Abstract
The effects of the intraoperative autologous blood donation and tepid temperature cardiopulmonary bypass (CPB) on blood system were investigated. Twenty-four patients with rheumatic heart valve diseases scheduled for open heart surgery were selected and divided randomly into group A (intraoperative autologous blood donation and tepid temperature, nasopharyngeal temperature was at 32-34 degrees C during CPB) and group B (control, nasopharyngeal temperature was at 25-28 degrees C during CPB). The plasmatic concentrations of GMP-140 and D-Dimer and the plasmatic activities of 6-keto-PGF1 alpha and AT-III were measured by using ELISA or substrate luminescence techniques before operation, at the end of CPB, after discontinuation of CPB and postoperatively. Red blood cell count, platelet count, hematocrit, the amount of blood drainage and the amount of blood transfusion needed were measured or recorded postoperatively. The results showed the plasmatic concentrations of GMP-140 and D-Dimer in group A were significantly less (P < 0.05) than those in group B during and after operation. The activity of 6-keto-PGF1 alpha in group A was higher (P < 0.05) than that in group B during and after operation. The AT-III activity in group A was less (P < 0.05) during CPB but higher 30 min after discontinuation of CPB than that in group B. The amount of postoperative blood loss (283 +/- 166 versus 722 +/- 194 ml, P < 0.01) and amount of blood transfusion (816 +/- 126 versus 1443 +/- 678 ml, P < 0.01) in group A were significantly less than those in group B, respectively. The red blood cell count, platelet count and hematocrit in group A were significantly higher than those in group B after operation. The results suggests intraoperative autologous blood donation and tepid temperature have a good protection on blood system and can reduce postoperative non-surgical bleeding.