RESUMEN
The study was performed to examine a possible augmentation of systemic administration of tranexamic acid by the additional topical application during heart valve surgery in the post-aprotinin era. One-hundred patients were enrolled in the study and all the patients were given tranexamic acid intravenously. The participants were randomized into two groups (A, n = 49; B, n = 51), and before commencing the sternal suturing, the study solution (group A: 250 ml of normal saline + tranexamic acid 2.5 g, placebo group B: 250 ml of normal saline) was poured into the pericardial cavity. The cumulative blood loss (geometric means [95% confidence intervals]) 4 h after the surgery was 86.1 [56.1, 132.2] ml in group A, and 135.4 [94.3, 194.4] in group B, test for equality of geometric means P = 0.107, test for equality of variances P = 0.059. Eight hours after the surgery, the blood loss was 199.4 [153.4, 259.2] ml in group A, 261.7 [205.1, 334.0] ml in group B, P = 0.130 and P = 0.050, respectively. Twenty-four hours postoperatively the blood loss was 504.2 [436.0, 583.0] ml in group A, 569.7 [476.0, 681.7] ml in group B, P = 0.293 and P = 0.014, respectively. The proportion of patients transfused postoperatively by fresh frozen plasma differed significantly between the two study groups (group A: n = 21, group B: n = 36, P = 0.008). Our hypothesis is supported by a significant difference in the inter-group variance of blood loss and the proportion of patients requiring fresh frozen plasma; however evident differences in mean postoperative blood loss were not statistically significant.
Asunto(s)
Antifibrinolíticos/administración & dosificación , Transfusión de Componentes Sanguíneos , Procedimientos Quirúrgicos Cardíacos , Válvulas Cardíacas/cirugía , Hemorragia Posoperatoria/terapia , Ácido Tranexámico/administración & dosificación , Anciano , Método Doble Ciego , Femenino , Humanos , Infusiones Intravenosas , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de TiempoRESUMEN
Although in many cardiac surgery centers pharmacological strategies based on fibrinolytic inhibitors are used on a routine basis, detailed knowledge of fibrinolysis during various settings of coronary surgery is still limited. Sixty-five patients scheduled for coronary surgery were randomized into 3 groups: group A--conventional coronary artery bypass grafting, group B--off-pump surgery, and group C--coronary artery bypass grafting with modified, rheoparin coated cardiopulmonary bypass with the avoidance of reinfusion of cardiotomy blood into the circuit. The sampling time points for rotation thromboelastographic evaluations were as follows: preoperatively, 15 minutes after sternotomy, on the completion of peripheral bypass anastomoses, at the end of the procedures, and 24 hours after the end of surgery. D-dimer levels were evaluated before surgery, at the end of procedures, and 24 hours after surgery. Thromboelastographic signs of fibrinolysis (evaluated by Lysis Onset Time-intergroup differences at 60 and 150 minutes of assessment: P = 0.003 and P < 0.001, respectively) were clearly detectable during cardiopulmonary bypass in group A, but not at any time in groups B and C. At the other sampling times all thromboelastographic parameters were similar in all groups. In group A, no exceptional bleeding tendency (during 24 hours), as compared to groups B and C (geometric means and 95% confidence intervals: group A: 686.7 [570.8; 826.1] mL, group B: 555.3 [441.3; 698.9] mL, group C: 775.6 [645.1; 932.3] mL, P = 0.157), and no significant correlations between Lysis Onset Time, postoperative blood loss, and D-dimer levels were found. No significant differences in postoperative blood loss related to cardiac surgeons and assistant surgeons were detected. Thromboelastographic signs of increased fibrinolysis were detectable in the important proportion of coronary surgery patients operated on with the use of conventional cardio-pulmonary bypass, but not in off-pump patients and those operated on with the biocompatible surface-modified circuit without reinfusion of cardiotomy suction blood. These signs resolved spontaneously at the end of surgery and were not associated with increased postoperative bleeding. No significant correlation with D-dimer levels was found.
Asunto(s)
Puente de Arteria Coronaria , Productos de Degradación de Fibrina-Fibrinógeno/análisis , Fibrinólisis/fisiología , Hemorragia Posoperatoria , Tromboelastografía , Anciano , Puente de Arteria Coronaria/métodos , Puente de Arteria Coronaria Off-Pump , Femenino , Humanos , Masculino , Estudios ProspectivosRESUMEN
BACKGROUND: The exact role of venous pooling in the pathogenesis of vasovagal syncope (VVS) is not fully elucidated. P-wave duration on an electrocardiogram can serve as a measure of atrial volume. METHODS: Sixty-six patients (15 men, 51 women, mean age 32 years) with unexplained syncope were enrolled in the study.P-wave duration and the P-wave axis (PWA) were measured during passive head-up tilt test (HUT) in order to evaluate dynamic changes of atrial filling in patients with VVS. RESULTS: HUT was positive in 40 patients (6 men, 34 women, mean age 32 +/- 9 years) and negative in 26 patients (9 men, 17 women, mean age 33 +/- 8 years). The P-wave duration was significantly reduced in HUT-positive patients at the onset of symptoms as compared to 5 minutes (88.8 +/- 11.9 vs 96.2 +/- 12.0 ms, P = 0.008), and baseline (88.8 +/- 11.9 vs 96.8 +/- 13.8 ms, P = 0.005). The P-wave duration was significantly shorter at the onset of presyncope in HUT-positive patients as compared to HUT-negative patients (88.8 +/- 11.9 vs 100.3 +/- 11.2 ms, P = 0.0002). In HUT-positive patients, a significant increase in PWA was found at the onset of symptoms when compared to baseline (67.7 +/- 22.1 degrees vs 47.9 +/- 14.9 degrees, P < 0.0001) and 5 minutes of HUT (67.7 +/- 22.1 degrees vs 54.4 +/- 14.9 degrees, P = 0.005). At the time of syncope, PWA was more inferior in HUT-positive patients than in HUT-negative patients (67.7 +/- 22.1 degrees vs 51.8 +/- 13.8 degrees, P = 0.015). CONCLUSIONS: VVS is associated with the reduction in P-wave duration and the increase in PWA, which can be a result of exaggerated venous pooling and reduction in atrial volume.