Wetland technology for the treatment of HCH-contaminated water - Case study at Hajek site.

Hexachlorocyclohexanes (HCH) isomers and their transformation products, such as chlorobenzenes (ClB), generate severe and persistent environmental problems at many sites worldwide. The Wetland technology employing oxidation-reduction, biosorption, biodegradation and phytoremediation methods can sufficiently treat HCH-contaminated water. The treatment process is inherently natural and requires no supplementary chemicals or energy. The prototype with a capacity of 3 L/s was installed at Hajek quarry spoil heap (CZ), to optimize the technology on a full scale. The system is fed by drainage water with an average concentration of HCH 129 µg/L, ClB 640 µg/L and chlorophenols (ClPh) of 16 µg/L. The system was tested in two years of operation, regularly monitored for HCH, ClB and ClPh, and maintained to improve its efficiency. The assessment was not only for environmental effects but also for socio and economic indicators. During the operation, the removal efficiency of HCH ranged from 53.5 % to 96.9 % (83.9 % on average) depending on the flow rate. Removal efficiency was not uniform for individual HCH isomers but exhibited the trend: α = Î³ = Î´ > ß = Îµ. The improved water quality was reflected in a biodiversity increase expressed by a number of phytobenthos (diatoms) species, a common biomarker of aquatic environment quality. The Wetland outranked the conventional WWTP in 10 out of the 15 general categories, and it is the most relevant scenario from the socio, environmental, and economic aspects.

Fibrinolytic inhibitors in off-pump coronary surgery: a prospective, randomized, double-blind TAP study (tranexamic acid, aprotinin, placebo).

OBJECTIVE: To evaluate and compare hemostatic effects of tranexamic acid vs. aprotinin vs. placebo in off-pump coronary artery bypass (OPCAB) surgery and, in addition, to assess the safety of fibrinolytic inhibitors therapies. METHODS: In a prospective, randomized, double-blind study finally 91 patients undergoing OPCAB were investigated (group A, n=32, tranexamic acid 1g before skin incision and continuously 200mg/h; group B, n=29, aprotinin 1,000,000IU before skin incision and 250,000IU/h; group C, n=30, placebo). RESULTS: Highly significant inter-group differences were found in cumulative blood loss within 4h (geometric means [95% confidence intervals]-group A: 89.3 [72.7, 109.8] mL, group B: 72.3 [49.2, 106.3] mL and group C: 192.3 [151.8, 243.5] mL) (P<0.001), within 8h (group A: 152.1 [120.7, 191.6] mL, group B: 130.3 [88.1, 192.8] mL and group C: 283.8 [226.0, 356.3] mL) (P=0.001), and within 24h postoperatively (group A: 410.3 [337.6, 498.6] mL, group B: 345.8 [256.0, 398.2] mL and group C: 619.8 [524.3, 732.8] mL) (P<0.001). At all time points, placebo group C was significantly distinct from the groups treated with fibrinolytic inhibitors (groups A and B). However, no differences between groups A and B were found. Both mean hemoglobin and hematocrit values 24h postoperatively were different between the groups (P=0.018 and P=0.077, respectively), acheiving the lowest value in group C. Number of re-transfuzed patients was highest in group C, but without statistical significance (either packed red blood cells, P=0.119 or fresh-frozen plasma, P=0.118). We observed one postoperative myocardial infarction in aprotinin treated group B and one temporary postoperative myocardial ischemia in placebo group C, no cerebrovascular or pulmonary embolism was noticed. Treated groups A and B did not demonstrate postoperative increase in mean levels of myocardial enzymes, compared with group C. Significantly higher mean values of D-dimer were found in group C 24h postoperatively (P<0.001). CONCLUSIONS: Both tranexamic acid and aprotinin seem to be similarly effective in the reduction of postoperative blood loss in OPCAB. Tranexamic acid appears to be cost-effective and safe alternative to aprotinin.

One-year coronary bypass graft patency: a randomized comparison between off-pump and on-pump surgery angiographic results of the PRAGUE-4 trial.

BACKGROUND: Off-pump coronary bypass surgery has become a widely used technique during recent years. However, limited data are available with regard to 1-year patency of bypass grafts implanted on the beating heart in unselected consecutive bypass surgery candidates. The aim of this study was to compare 1-year angiographic patency of bypass grafts done on the beating heart (off pump) with those done classically (on pump). METHODS AND RESULTS: The PRAGUE-4 trial randomized 400 consecutive nonselected cardiac surgery candidates into group A (on pump; n=192) and group B (off pump; n=208). One-year follow-up coronary angiography was done in 255 patients. The arterial graft patency after 1 year was 91% in both groups. Saphenous graft patency was 59% (on pump) versus 49% (off pump; P=NS). Saphenous graft patency per patient was lower in the off-pump group: 0.7 patent anastomosis per patient versus 1.1 patent anastomosis in the on-pump group (P<0.01). There were 46% on-pump patients with all grafts patent versus 52% off-pump patients (P=NS). Grafts anastomosed distally to collateralized chronic total occlusions of native coronary arteries remained patent in 100% on the left anterior descending artery compared with 23% on other arteries (P<0.0001). CONCLUSIONS: The patency of arterial coronary bypass grafts done on the beating heart is excellent and equal to grafts done on pump. The off-pump procedure in the unselected patient population results in fewer patent saphenous grafts per patient.

Off-pump versus on-pump coronary surgery: final results from a prospective randomized study PRAGUE-4.

BACKGROUND: Off-pump coronary artery bypass surgery is becoming increasingly popular despite the lack of sufficient evidence from randomized trials. The aim of our prospective, randomized, single-center study was to examine the role of off-pump revascularization among nonselected patients. METHODS: A total of 400 consecutive nonselected patients (mean age 63 years) scheduled for isolated coronary revascularization were randomized by a cardiologist into two groups: A (on-pump) and B (off-pump). The cardiac surgeon was allowed to change the operative technique at any time after randomization. The only exclusion criterion was an emergency procedure. The primary end point was any of the following within 30 days: death, myocardial infarction, stroke, or new renal failure requiring hemodialysis. The study was analyzed on the intention-to-treat principle. RESULTS: The primary end point occurred in 4.9% of patients in group A versus 2.9% in group B (not significant). Mortality was 1.1% in group A versus 2.0% in group B (not significant). Preoperative crossover occurred in 5.4% of patients in each group (not significant). Intraoperative conversion was necessary in 9.8% of patients in group B versus 1.1% of patients in group A (p < 0.001). Group B patients had fewer distal anastomoses (2.3 versus 2.7 in group A; p < 0.001), less blood loss (560 versus 680 mL; p < 0.001), lower postoperative creatine kinase MB levels (0.15 versus 0.56 microkat/L; p < 0.001) and lower total hospital costs (3,451 versus 4,387; p < 0.001). CONCLUSIONS: In our study off-pump technique was applicable in 85% of nonselected patients and is at least as clinically safe and effective as on-pump surgery.

Routine immediate extubation for off-pump coronary artery bypass grafting without thoracic epidural analgesia.

BACKGROUND: The expansion of coronary surgery on the beating heart without cardiopulmonary bypass has led to increasing interest in ultra-fast track anesthesia, allowing extubation of the patient in the operating theater. The techniques described to date combined general anesthesia with thoracic epidural analgesia. We report the routine application of a technique that allows immediate extubation in the majority of patients undergoing off-pump coronary artery bypass grafting without thoracic epidural analgesia. METHODS: Fast-track anesthesia using an ultra-shortacting opiate remifentanil, without epidural catheter insertion, was used in 160 unselected patients undergoing off-pump coronary artery bypass grafting (aged 43 to 83 years, mean 65 years). There were an average of 2.2 bypass procedures per patient, with the left internal mammary artery used in 93%. Contraindications to immediate extubation were (except for failure to meet standard extubation criteria) hemodynamic instability and persistent bleeding at the end of operation. Satisfactory postoperative pain control was achieved by continuous remifentanil (0.0125 to 0.05 microg x kg(-1) x min(-1)). RESULTS: Operating theater extubation within 10 minutes of the end of operation was feasible in 150 patients (94%). Five patients (3%) were extubated within 2 hours, and the remaining 5 patients (3%) were converted to standard anesthesia. There were no deaths during hospitalization. Major complications included myocardial infarction and transient ischemic attacks (2 patients each). No pulmonary complications were seen. Episodes of atrial fibrillation occurred in 21% of the patients undergoing operation. CONCLUSIONS: Immediate extubation is possible in most patients after off-pump coronary artery bypass grafting even without thoracic epidural analgesia. We believe this type of less invasive cardiac anesthesia is safe and promising.

Development of C-reactive protein and fibronectin levels in coronary surgery patients: a comparison of on-pump, off-pump sternotomy and off-pump left anterior small thoracotomy groups.

In this prospective study, we monitored two laboratory parameters, C-reactive protein (CRP) and fibronectin (FIN) levels, in 30 patients undergoing elective surgery for ischemic heart disease. These patients were divided into three groups according to the surgical procedure used: group A, approach through a median sternotomy with the use of extracorporeal circulation; group B, approach through a median sternotomy without the use of extracorporeal circulation; and group C, approach through a left anterior small thoracotomy (LAST) without the use of extracorporeal circulation. Peak CRP levels were found in all three groups on the second postoperative day, with the mean levels being statistically significantly higher in group C. This group also showed the highest mean CRP levels on the third and fourth postoperative days, with the difference being statistically nonsignificant. These findings can be explained by an enhanced production of cytokines, which in turn trigger CRP synthesis, induced by postoperative pain due to the LAST procedure. No statistically significant correlation between preoperative CRP levels and their postoperative development was found. None of the groups studied showed any statistically significant decrease in FIN plasma levels, either prior to adjustment for hemodilution or after adjustment for hematocrit and serum albumin.