Efficacy of aminocaproic, tranexamic acids in the control of bleeding during total knee replacement: a randomized clinical trial.

BACKGROUND: Risks and costs of allogeneic blood transfusions mandate strategies to reduce blood loss in surgery. The objective of this study was to assess the efficacy of antifibrinolytic treatment in reducing perioperative blood loss during total knee replacement. METHODS: A double-blind, randomized and placebo-controlled clinical trial was carried out on 127 patients undergoing total knee replacement. Patients in the study group received tranexamic acid 10 mg kg(-1) i.v. just before the tourniquet was deflated and 3 h later, or epsilon-aminocaproic acid 100 mg kg(-1) before tourniquet deflation followed by continuous perfusion (1 g h(-1)) during 3 h. External perioperative blood loss was measured and total blood loss was calculated. The number of patients transfused and number of packed red cell (PRC) units transfused was recorded and possible postoperative thromboembolic complications were investigated. RESULTS: Total blood loss [mean (sd)] was 1099 ml (535) in the group that received antifibrinolytic agents and 1784 ml (660) in the control group (P<0.001). Five patients (7.5%) in the study group and 23 (38.3%) in the control group (P<0.001) received blood transfusions; the first group received a mean of 0.10 PRC unit per patient and the second, 0.58 (P<0.001). Mean reduction in haemoglobin levels (g dl(-1)) between preoperative and fifth day postoperative readings was 2.5 (0.9) in the study group and 3.4 (1.2) in the control group (P<0.001). Clinical assessment did not reveal any thromboembolic complications. CONCLUSIONS: Antifibrinolytic agents produce a significant decrease in blood loss in patients undergoing total knee replacement, reflected in a reduction in the number of blood transfusions required.

[Humoral immune response to the capsular polysaccharide of Neisseria meningitidis serogroup C in an antimeningococcal BC vaccination trial in Antioquia, Colombia]. / Respuesta inmune humoral al polisacárido capsular de Neisseria meningitidis serogrupo C en un ensayo de vacunación antimeningocócica BC en Antioquia, Colombia.

As a complement to studying humoral immune response to the proteins of an antimeningococcal vaccine (VA-MENGOC-BC) against serogroups B and C, the humoral immune response to polysaccharide C of the vaccine was also evaluated in 142 children from 1 to 5 years of age in an area of the Department of Antioquia, Colombia. Paired pre-(T0) and post-vaccination (T1) sera were tested for IgG response by means of ELISA and for serum lytic capacity against a strain of serogroup C by means of the bactericidal antibodies test (BAT). Response to the vaccine was statistically significant (P < 0.01) by both techniques. PAB demonstrated seroconversion (T1/T0 > or = 4) in 88% (95% confidence interval, CI95%: 80% to 95%) of all those who were seronegative before vaccination. The proportion of seroconversion in children 2, 3, and 4 years of age was 86% or more. Of all the sera tested with ELISA, 93% (CI95%: 89% to 97%) showed response to the vaccine (T1/T0 > or = 2), and 98% (CI95%: 94% to 100%) of the subjects with T0 < or = 500 U/mL seroconverted. In this sample, the vaccine stimulated a specific and protective response as measured by ELISA and BAT, the latter test being utilized to evaluate protection status.