Inhibition of cytokine synthesis by peritoneal dialysate persists throughout the CAPD cycle.

The current study focused on the effect of continuous ambulatory peritoneal dialysis (CAPD) dialysate obtained following different intraperitoneal dwell periods on the release of interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF alpha) from mononuclear leukocytes (PBMC). Aliquots of 5 x 10(6)/ml healthy peripheral PBMC were exposed to fresh or spent CAPD dialysate (10-240 min of intra-peritoneal dwell) and stimulated with Escherichia coli endotoxin (10 micrograms/ml, 2h). IL-6 and TNF alpha in cell supernatants were determined by specific enzyme immunoassays. Control PBMC in physiological buffer released 361 +/- 70 pg/ml IL-6 and 717 +/- 147 pg/ml TNF alpha (mean +/- SEM, n = 8), whereas exposure to fresh dialysis fluids severely suppressed cytokine release from PBMC (less than 30 pg/ml IL-6 and less than 15 pg/ml TNF alpha). A significant inhibition of IL-6 and TNF alpha release was also observed in PBMC exposed to spent dialysate. The inhibitory capacity of the spent fluids was pronounced with increasing intra-peritoneal dwell time (10 min: 183 +/- 45 pg/ml IL-6 and 538 +/- 109 pg/ml TNF alpha; 240 min: 26 +/- 5 pg/ml IL-6 and 105 +/- 30 pg/ml TNF alpha; mean +/- SEM, n = 16). These data indicate that the impairment of cell responsiveness following exposure of PBMC to peritoneal dialysate is not restricted to the unused fluids, but is also observed following intra-peritoneal equilibration. Moreover, our findings suggest the presence of cytokine inhibitory factors in the peritoneal dialysate of CAPD patients which appear to accumulate in the peritoneal effluent during the CAPD cycle.     

Cardiac interleukin-6 release and myocardial recovery after aortic crossclamping. Crystalloid versus blood cardioplegia

BACKGROUND: Pro-inflammatory cytokines may play an important role in patient response to cardiopulmonary bypass (CPB). Since the myocardium is proposed to be a major source of cytokines, we studied the influence of the cardiolpegia type on interleukin-6 release and early myocardial recovery. METHODS: Experimental design: prospective, randomized study. Setting: university hospital, operative and intensive care. Patients: 20 consecutive patients (3 females) scheduled for elective coronary artery bypass grafting (CABG), mean age 62.8+/-5 years, history of myocardial infarction 11/20, left ventricular ejection fraction 62.9+/-15%. Interventions: patients were operated on using randomly either cold blood cardioplegia (B, n = 10) or cold crystalloid cardioplegia (C, n = 10). Measures: plasma levels of interleukin-6 (IL-6) were measured prior to CPB, after aortic declamping, after CPB, 1 hour, 6 hours and 12 hours postoperatively. RESULTS: Groups were comparable with respect to demographic data, left ventricular function, number of grafts, CPB and aortic crossclamp time. Group B patients demonstrated significant lower IL-6 levels after 1 hour (210+/-108 vs. 578+/-443 pg/ml), 6 hours (204+/-91 vs. 1210+/-671 pg/ml) and 12 hours (174+/-97 vs. 971+/-623 pg/ml). Post-CPB cardiac index was superior in group B (3.9+/-0.3 vs. 3.2+/-0.3 l/min/m2, p<0.05) with similar doses of inotropes. Group B patients could earlier be weaned off respirator (10+/-4 vs. 13+/-4 hours, p<0.05) and showed minor blood loss (635+/-211 vs. 918+/-347 ml, p<0.05). CONCLUSIONS: Inflammatory response to CPB is associated with delayed myocardial recovery. The use of blood cardioplegia may attenuate inflammatory reactions.     

Nitric oxide expression by interleukin-10 in the endoscopic and open methods of vein harvesting in coronary artery bypass surgery.

OBJECTIVE: Interleukin-10 (IL-10) is an anti-inflammatory cytokine that suppresses lymphocyte functions, regulates production of proinflammatory cytokines, and suppresses nitric oxide production by activated macrophages. We examined IL-10 expression and its value as a surrogate index for nitric oxide (NO) production in endothelial cultures obtained from saphenous vein samples. METHODS: Using 2 different techniques (the open and endoscopic), we harvested samples of human saphenous veins from 90 randomly selected patients undergoing coronary artery bypass surgery (CABG). Endothelial cells collected from the vein samples retrieved through both techniques were cultured for 72 hours. Using a solid phase enzyme linked-immuno-sorbent assay (ELISA), we analyzed pre- and postoperative sera, in addition to the supernatants from the cultures, for IL-10. RESULTS: Mean preoperative levels of IL-10 (0.09 +/- 0.04 pg/mL) did not differ significantly from that for postoperative sera (0.14 +/- 0.17 pg/mL) (P = 0.54). Mean IL-10 levels for endothelial cell culture supernatants did not differ significantly between the endoscopic (0.32 +/- 0.39 pg/mL) and the open method (0.46 +/- 0.80 pg/mL) (P= 0.30). CONCLUSION: Our findings indicate that endoscopic and open saphenectomies are technically comparable with respect to their effects on IL-10 release during saphenous vein harvesting for CABG. We recommend the endoscopic method for its low morbidity and earlier hospital discharge.     

Influence of ischemic preconditioning and blood cardioplegia protection on postischemic endothelial activation in coronary bypass surgery

Summary Background Hypothermic ischemia in open heart surgery and cardiopulmonary bypass involve a postischemic in-flammatory reaction caused by an activation of leukocytes and endothelia with the systemic release of cytokines and adhesion molecules. The present study addresses the question, if an amelioration of postischemic endothelial activation in the heart could be achieved by means of cardioplegic protection or ischemic preconditioning. In a randomized prospective study patients underwent a normothermic preconditioning procedure either followed by crystalloid or blood cardioplegia during coronary bypass surgery. Methods Patients (n=28) were included and randomized in the study according to defined criteria: Group A received St. Thomas cardioplegia, group B cold blood cardioplegia. Ischemic precon-ditioning was performed twice at normothermia under a cardiopulmonary bypass (CPB) for 5 min followed by 10 min of reperfusion before coronary aortic bypass graft (CABG) using St. Thomas (group C) or blood cardioplegia (group D) hypothermic protection. In coronary sinus blood and arterial blood myocardial (creatine-kinase myoglobin [CK-MB]) and endothelial activation (endothelin, IL-6, IL-8, sE-selectin, soluble vascular adhesion molecule-1 [sVCAM-1], soluble intercellular adhesion molecule-1 [sICAM-1]) parameters were investigated 1, 3, 6, 9, 12, and 24 h after coronary reperfusion. Results 1) Parameters of myocardial injury (CK-MB, myoglobin) revealed increased levels at 1 h and 9 to 12 h after CABG. Levels at 12 h were lower in group B and D as compared to A and C. 2) Cytokines (IL-6, IL-8) showed increased levels 3 h after reperfusion with no difference between study groups. 3) Soluble adhesion molecules (E-selectin, VCAM-1, ICAM-1) were found increased in all groups 6 to 12 h after reperfusion. Lower levels were present in group D for E-selectin and VCAM-1. Conclusions The results indicate a sequence of cytokine and adhesion molecule release as a potential pathomechanism of myocardial reperfusion injury. Gradual decrease in the release of endothelial adhesion molecules in late myocardial injury was noted for blood cardioplegia and ischemic preconditioning. Amelioration of endothelial activation by means of preconditioning and blood cardioplegia may improve heart muscle recovery in open heart surgery with borderline ischemia time and organ dysfunction.      

IL-8, IL-6 and ICAM-1 in serum of paediatric patients undergoing cardiopulmonary bypass with and without cardiocirculatory arrest

BACKGROUND: The aim of the present study was to evaluate the systemic inflammatory response to CPB in paediatric patients undergoing surgical correction of congenital heart diseases. METHODS: Experimental design: comparative investigation. Setting: paediatric cardiology hospital Intervention: ICAM-1, IL-8, and IL-6 production were analysed before and during CPB, and after surgery in 9 paediatric patients, submitted to cardiocirculatory arrest (Group A); and in 11 without cardiocirculatory arrest (Group B). Measures: ICAM-1, IL-8, and IL-6 production were analysed from arterial samples before and during CPB, and after surgery. RESULTS: In group A vs group B a significant increase of IL-8 was detected during (297+/-250 vs 11+/-19 pg x ml(-1), p<0.001) and after (100+/-230 vs n.d. pg x ml(-1)) surgery and was correlated with the duration of operation (r=0.759; p=0.0001) and clamping time (r=0.738; p<0.05). After surgery in group A, IL-6 levels (35+/-43 pg x ml) were higher than those in group B (2+/-5 pg x ml), and a good correlation was observed between IL-6 and duration of aortic clamping (r=0.714; p=0.048), cardiac arrest, (r=0.714; p=0.048), and length of surgery (r=0.867; p=0.04). CONCLUSIONS: In children who underwent CPB with cardiocirculatory arrest cytokine production seems related to duration of operation and amplified by ischemia-reperfusion phenomena.     

The heart produces but the lungs consume proinflammatory cytokines following cardiopulmonary bypass.

OBJECTIVE: Proinflammatory cytokines, such as interleukin-6 (IL-6), and soluble adhesion molecules, such as E-selectin, may play an important role in patient response to cardiopulmonary bypass (CPB). We sought to define whether the heart and the lungs serve as important sources of these inflammatory mediators under clinical conditions of myocardial revascularization using CPB and cardioplegic arrest. METHODS: Plasma levels of IL-6 and E-selectin were measured in coronary sinus (CS), arterial, pulmonary arterial (PA) and left atrial (LA) blood samples taken from 12 consecutive patients (68.3 +/- 11 years; five females) undergoing coronary artery bypass grafting (CABG). Blood samples were collected preoperatively, after reperfusion, and 1, 6, 12 and 18 h following surgery. CS and LA blood was drawn using transcutaneous catheters. PA artery blood was obtained through a Swan-Ganz catheter. Cytokine levels were determined by standard enzyme linked immunosorbent assay (ELISA) technique. RESULTS: A mean of 3.8 +/- 1 coronary anastomoses were performed. The CPB time and aortic X-clamp time were 91 +/- 15 and 45 +/- 10 min, respectively. IL-6 levels increased significantly after CPB and peaked 6 h postoperatively. There was also a significant increase of E-selectin levels with an onset at 1 h and a peak at 12 h postoperatively. At all time points the IL-6 and E-selectin concentrations were significantly higher in the CS than in arterial blood. In contrast, the levels of both mediators measured in the LA were significantly lower than those in the PA. CONCLUSION: The reperfusion of ischemic myocardium during CABG results in a significant increase in plasma levels of IL-6 and E-selectin. Our data indicate that the myocardium, but not the lungs, is a predominant source of IL-6 and E-selectin release following CPB. The lungs may consume rather than release those mediators during reperfusion. Not the CPB per se, but the myocardial ischemia seems to be crucial in the pathogenesis of the inflammatory response observed following open heart surgery.     

The complex pattern of cytokines in sepsis. Association between prostaglandins, cachectin, and interleukins.

Although the cytokines tumor necrosis factor (TNF), interleukin-1 (IL-1), and interleukin-6 (IL-6) are important mediators of hemodynamic, metabolic, and immunologic alterations in the host during sepsis, it is not known whether there is any association between the release of these cytokines and prostanoids during sepsis. Sepsis induced by cecal ligation and puncture in rats led to a persistent elevation (p less than 0.05) of plasma TNF until 10 hours, steadily increasing (p less than 0.05) IL-1 plasma levels, and enhanced (p less than 0.05) IL-6 plasma levels at all time points compared to the sham group. Prostaglandin E2 plasma levels were elevated (p less than 0.05) at 5 hours (153 +/- 29 pg/mL; control: 47 +/- 11 pg/mL) and 10 hours (96 +/- 16 pg/mL; control: 21 +/- 5 pg/mL). Prostaglandin E2 production by splenic macrophages (sM phi) from septic animals was increased (p less than 0.05) at 5 hours (9.1 +/- 2.2 ng/mL) and 10 hours (5.6 +/- 1.5 ng/mL) compared to controls (3.3 +/- 0.3 ng/mL at 5 hours; 1.3 +/- 1.3 ng/mL at 10 hours). Incubation of sM phi from septic animals with ibuprofen enhanced (p less than 0.05) IL-1 and TNF synthesis, while IL-6 production was reduced (p less than 0.05). These results indicate that the alterations in prostanoid release and elevated plasma prostanoids may regulate the release and consequently the circulating levels of cytokines during sepsis.     

Tumor necrosis factor-induced mortality is reversed with cyclooxygenase inhibition.

OBJECTIVE: The authors hypothesized that TNF would induce eicosanoid synthesis, and a cyclooxygenase inhibitor would attenuate both eicosanoid synthesis and improve survival in an LD90 TNF-induced (150 ng/kg/i.v./5 min) mortality model. SUMMARY BACKGROUND DATA: Tumor necrosis factor is a cardinal mediator in sepsis; however, little is known about its effects on arachidonate metabolism. METHODS: Conscious male rats with carotid arterial and jugular venous catheters were randomized for mortality: group I, TNF alone (150 kg/i.v./15 min, n = 30); group II, ibuprofen (30 mg/kg/i.v. at t = -20 and +240 min), plus TNF, (n = 28); and for hemodynamics, eicosanoid synthesis, blood gases: group III, TNF alone, (n = 8); group IV, ibuprofen + TNF (n = 8); group V, monoclonal antibody to TNF plus TNF (n = 8). Mortality was determined at 4-72 hr. Other parameters determined over 4 hours (0, 5, 60, 120, 240 min). RESULTS: TNF stimulated synthesis of (a) TXB2 (71 +/- 30 pg/ml, mean +/- SE at base vs. 117 +/- 18 at 4 hr, p < 0.02); (b) PGE2 (70 +/- 6 pg/ml at base vs. 231 +/- 68 at 4 hr, p < 0.02); (c) 6PGF (52 +/- 6 pg/ml at base vs. 250 +/- 80 at 4 hr, p < 0.02). Ibuprofen significantly (p < 0.05) inhibited eicosanoid synthesis from TNF. TNF-induced mortality (87%, 26/30) was dramatically decreased with ibuprofen (11%, 3/28), at 4, 24, and 72 hr (p < 0.01). Monoclonal antibody to TNF prevented all abnormalities and had 100% survival. Hemodynamic events were similar in both groups, but metabolic acidosis was attenuated with ibuprofen. CONCLUSIONS: TNF stimulates arachidonic acid metabolism in vivo. A cyclooxygenase inhibitor attenuates eicosanoid synthesis and dramatically improves survival. TNF appears to have different effect on tissues that synthesize certain eicosanoids. Hypotension from TNF is not mediated via the eicosanoids. TNF-induced mortality, like endotoxemia/sepsis may be mediated, in part, via arachidonic acid metabolites. These new findings support the notion that cyclooxygenase inhibitors may be used as adjunctive therapy in clinical sepsis.     

Relation of inflammatory cytokines to atrial fibrillation after off-pump coronary artery bypass grafting.

OBJECTIVE: It has been observed that a systemic inflammatory response after on-pump coronary artery bypass grafting (CABG) participates in the pathogenesis of postoperative atrial fibrillation (AF). In patients undergoing off-pump CABG, it is plausible that inflammation is associated with the development of postoperative AF. The present study examined relation of proinflammatory cytokines, which play an important role in the upstream of inflammatory cascade, to the development of AF after off-pump CABG. METHODS: The present study included 39 patients undergoing off-pump CABG. Tumor necrosis factor-alpha (TNF-alpha), interleukin (IL)-6, and IL-8, were measured by enzyme-linked immunosorbent assay, on anesthetic induction, after sternotomy before anastomoses, at the completion of anastomoses, 3 and 6h thereafter, and on postoperative days (POD) 1-4. C-reactive protein (CRP) was also measured by turbidimetric immunoassay, preoperatively, and on POD 1, 2, 3, 6, 9, and 13. RESULTS: Eleven patients (28%) developed postoperative AF. Patients with postoperative AF were older (70+/-6.4 years vs 60+/-8.8 years, P=0.001); however, there was no difference in other pre- and perioperative variables. TNF-alpha level did not change during the study period. However, IL-8 and CRP levels significantly increased after the surgery, although there was no significant difference between the two groups. IL-6 level also increased after the surgery with its peak at 6h after the completion of anastomoses. IL-6 levels of 3 and 6h after anastomoses were significantly higher in patients with postoperative AF (360+/-143 pg/ml vs 230+/-94 pg/ml, P=0.0047, 435+/-175 pg/ml vs 247+/-102 pg/ml, P=0.0005, respectively). Logistic regression analysis indicated that the highest quartile of IL-6 level immediately after the surgery (odds ratio 7.63; 95% CI, 1.06-54.9; P=0.04) and age (odds ratio 1.18; 95% CI, 1.01-1.39; P=0.04) independently predict postoperative AF. Furthermore, the maximum level of IL-6 immediately after the surgery significantly correlated to age and intraoperative blood loss (r=0.04, P=0.01, and r=0.47, P=0.04, respectively). CONCLUSIONS: Advanced age was a major risk factor for postoperative AF. Furthermore, inflammatory response induced by surgical trauma was also associated with the development of AF after off-pump CABG.     

冠心病患者围手术期炎症反应的研究

目的　探讨体外循环或非体外循环下冠状动脉搭桥和激光心肌打孔治疗冠心病时围手术期炎症因子变化的特点 ,为冠心病围手术期的临床治疗提供参考。　方法　测定 37例冠心病患者及 10例瓣膜病患者术前 ,搭桥或打孔前 ,主动脉开放时 (搭桥结束时或打孔后 )及术后 3、6、2 4h的血浆肿瘤坏死因子 (TNF α)、白介素 6 (IL 6 )、C反应蛋白 (CRP)的水平。　结果　术后患者血浆TNF α、IL 6、CRP水平均有一定程度升高 ,使用体外循环患者TNF α为 (4 10± 0 71)pg/ml,显著高于不使用者的 (1 34± 0 2 9)pg/ml,差异有显著性意义 (P <0 0 5 ) ;两者IL 6差异无显著性意义 (P >0 0 5 )。冠状动脉搭桥患者术后CRP为 (12 89± 0 2 9) μg/ml,高于瓣膜病患者的 (12 0± 0 31) μg/ml,差异有显著性意义 (P <0 0 5 )。　结论　冠心病患者 ,冠状动脉搭桥、激光打孔手术后 ,围手术期均有一定程度的炎症反应 ,体外循环者反应较重     

Extracorporeal circulation does not induce intra-alveolar release of Endothelin 1, but only a modest overproduction in pulmonary circulation.

OBJECTIVE: To investigate whether ECC may produce regional liberation of inflammatory mediators capable of inducing vascular effects and organ damage. EXPERIMENTAL DESIGN: Comparative study [corrected]. SETTING: Cardiac surgery department in a University hospital. PATIENTS: Fifteen patients undergoing coronary artery bypass grafting (CABG, group A) and ten patients operated for infrarenal abdominal aortic aneurysm (controls, group B) have been studied. MEASURES: Levels of Interleukin 1beta (IL1), Tumor Necrosis Factor alpha (TNF), Interleukin 6 (IL6), and Endothelin 1 (ET1) were measured in pulmonary capillary, arterial, and venous blood and in bronchoalveolar lavages (BAL) before, during and after extracorporeal circulation (ECC) or surgical intervention. RESULTS: TNF-alpha (never >35 pg/ml) and IL1beta (range 20-300 pg/ml) values did not change over time for both groups. IL6 concentrations in all samples of group A increased between five and twenty fold, during and after ECC (from 3-5 pg/ml up to 240 pg/ml, p<0.001). This trend was similar in controls after surgical stress. Endothelin 1 was always undetectable in the BAL fluid, with a modest, but significant increase in pulmonary capillary blood of group A, after ECC, (from 11+/-4 pg/ml to 18+/-5 pg/ml, p<0.001). This increment correlated well with the PVR increase, but was transient and after 24 hours, ET1 values returned to baseline levels. Mean values of ET1 increased also in controls, but not significantly. CONCLUSIONS: ECC may induce ET1 liberation in pulmonary circulation with transient pulmonary vasoconstriction, but wihout intra-alveolar release, or lung damage. Augmented concentrations of IL6 probably express a response to surgical procedure rather than an effect exclusively related to ECC.     

Cytokines, the acute-phase response, and resting energy expenditure in cachectic patients with pancreatic cancer.

OBJECTIVE: To determine whether resting energy expenditure (REE) is increased in cachectic patients with pancreatic cancer and to define the relation of tumor necrosis factor (TNF) and interleukin-6 (IL-6) production to the acute-phase response and to REE. METHODS: Measurement of REE (indirect calorimetry) and assessment of body composition (bioelectrical impedance analysis) were done in 21 patients with unresectable pancreatic cancer and on 16 age-related controls. The systemic inflammatory response in peripheral blood of the cancer patients was assessed using the acute-phase protein, C-reactive protein, and the cytokines TNF and IL-6. Production of these cytokines by peripheral blood mononuclear cells in vitro was also measured. RESULTS: Patients with pancreatic cancer had an elevated REE when compared with controls (73.4 +/- 5.0 vs. 53.5 +/- 1.6 kcal/kg body cell mass; p < 0.003). Resting energy expenditure was significantly greater in cancer patients with an acute-phase response (C-reactive protein > 10 mg/L) than in those who did not have such a response (85.5 +/- 10.0 [n = 9] vs. 64.3 +/- 3.0 [n = 12] kcal/kg body cell mass; p < 0.04). Tumor necrosis factor was not detected in the serum of any of the cancer patients. Serum IL-6 was detected but levels were not significantly different among cancer patients with or without an acute-phase response. In contrast, spontaneous production of TNF and IL-6 by isolated peripheral blood mononuclear cells was significantly greater in cancer patients with an acute-phase response that in those without (TNF: 1231 +/- 244 vs. 210 +/- 54 pg/ml/10(5) cells; p < 0.001; IL-6: 11.5 +/- 1.7 vs. 3.6 +/- 1.4 ng/mL/10(5) cells; p < 0.003). CONCLUSIONS: In pancreatic cancer at least a component of weight loss is due to increased REE. Furthermore, the presence of an acute-phase response identifies a group of patients who are markedly hypermetabolic. The serum concentration of TNF of IL-6 does not correlate with the presence of an acute-phase response, whereas rates of cytokine production by peripheral blood mononuclear cells are significantly greater in patients with such a response. This suggests that local rather than systemic cytokine production may be important in regulating the acute-phase response.     

Impact of kidney function on plasma troponin concentrations after coronary artery bypass grafting.

BACKGROUND: To date, there have been no studies reliably showing an influence of the kidney on the concentration of troponins. We therefore analysed the concentration curves in patients after coronary artery bypass grafting (CABG) according to their dependence on renal function. METHODS: We determined cardiac troponin I (cTnI), cardiac troponin T (cTnT) and creatinine in plasma in 28 patients after CABG. Discrimination into patients with normal (n=13) and impaired (n=15) renal function was based on creatinine clearance (Crea-Clear). The curves for cTnI and cTnT, as recorded by post-operative measurements, were approximated using mathematical functions. The curve parameters peak maximum (P(max)), peak position (P(pos)), half-height breadth (HHB) and area under the curve (AUC) were established after this. Assuming an exponential function, the half-life (t(1/2)) of cTnI was determined from the declining part of the curve. RESULTS: For both, cTnI and cTnT, significant differences in P(max), P(pos), HHB and AUC were detected after curve approximation. The t(1/2) values of cTnI were 25.1 h (22.0-35.3) for the group with normal renal function and 38.4 h (35.9-51.9) for patients with impaired renal function (P=0.001). An influence of diabetes mellitus (Dm), renal replacement therapy or the age of the patients could not be verified. CONCLUSION: The results of this study clearly demonstrate that kidney function has an impact on plasma troponin concentrations. In everyday clinical practice this has to be considered when interpreting elevated plasma troponin concentration in patients with impaired renal function.     

Inhibition of systemic inflammatory response with sodium nitroprusside in open heart surgery

BACKGROUND: A nitric oxide donor, sodium nitroprusside has been reported to reduce the inflammatory response during cardiopulmonary bypass (CPB). To investigate this, a double-blind and prospective study was conducted. METHODS: Twenty patients with multi vessel coronary disease were randomly chosen to form study (SNP) and control groups. In the SNP group, 0.5 microg/kg/min sodium nitroprusside were administered for 20 min right after the release of the aortic crossclamp. Mac-1 (CD11b/CD18) leukocyte adhesion molecule expressions, interleukin-6 levels were measured from radial artery blood as well as leukocyte and platelet counts in both groups at 6 different time points: a) before anesthesia, b) after heparin administration, c) after aortic crossclamp release, d) after protamine administration, e) 3 hours after the termination of CPB, f) 24 hours after the termination of CPB. RESULTS: The increase in Mac-1 expressions were not different between the two groups at any time point except the measurements after the administration of protamine. At this time point, Mac-1 expressions were not different between the groups (99.8+/-30.7 vs 134.6+/-95.1%, p=0.076), but higher when compared with the preinduction levels. IL-6 levels for SNP and control groups was 89+/-43 and 215+/-131 pg/dL, respectively (p=0.016) 3 hours after the termination of CPB. Twenty-four hours after the termination of CPB, IL-6 levels were still significantly higher in the control group (47+/-27 vs 111+/-68 pg/dL, p=0.039). Leukocyte and platelet counts were not different at any time point between the groups. CONCLUSIONS: Systemic inflammatory response in patients undergoing CPB can be reduced to a certain level with sodium nitroprusside, especially the activation of vascular endothelial cells can be inhibited, but activation of leukocytes still takes place.     

Comparison of minimally invasive closed circuit extracorporeal circulation with conventional cardiopulmonary bypass and with off-pump technique in CABG patients: selected parameters of coagulation and inflammatory system.

OBJECTIVE: Closed circuit extracorporeal circulation (CCECC) has been developed to reduce deleterious effects of standard cardiopulmonary bypass (CPB). This study compares the effects of CCECC (CORx system), CPB, and off-pump coronary artery bypass grafting (OPCAB) on red blood cell damage, coagulation activation, fibrinolysis and cytokine expression. METHODS: Thirty patients underwent coronary artery bypass grafting (CABG). Twenty of them were randomized into two groups: CCECC (n = 10), CPB (n = 10). While not randomized, OPCAB (n = 10) served as a separate reference group. CCECC and CPB patients received cardioplegic arrest. Interleukin 6 (IL-6), free hemoglobin (fHb), von Willebrand factor activity (vWf), thrombin-antithrombin-III-complex (TATc), prothrombin fragment 1.2 (F 1+2) and plasmin-antiplasmin complex (PAPc) were assessed preoperatively, perioperatively and 24 h postoperatively. RESULTS: CCECC showed significantly lower red blood cell damage than CPB (fHb: CCECC, 7.1+/- 5.7 micromol/l; CPB, 16.8+/-11.4 micromol/l; P = 0.025; OPCAB, 3.4+/-1.1 micromol/l). Perioperatively, CCECC exhibited significantly lower activation of coagulation and fibrinolysis than CPB, but did not differ from OPCAB (vWf: CCECC, 133+/-52%; CPB, 241+/-128%; P = 0.052; OPCAB, 153+/-58%; TATc: CCECC, 4.7+/-0.9 ng/ml; CPB, 31.1+/-15.8 ng/ml; P < 0.001; OPCAB, 2.4+/-0.6 ng/ml; PAPc: CCECC, 214+/-30 ng/ml; CPB, 897+/-367 ng/ml; P < 0.001; OPCAB, 253+/-98 ng/ml). In contrast, fibrinolysis markers and IL-6 were markedly increased in CCECC postoperatively (PAPc: CCECC, 458+/-98 ng/ml; CPB, 159+/-128 ng/ml; P < 0.001; OPCAB, 262+/-174 ng/ml; IL-6: CCECC, 123.4+/-49.8 pg/dl; CPB, 18.8+/-13.1 pg/dl; P < 0.001; OPCAB, 31.6+/-26.2 pg/dl). CONCLUSIONS: CCECC for CABG is associated with a significant reduction of red blood cell damage and activation of coagulation cascades similar to OPCAB when compared with conventional CPB while a delayed fibrinolytic and inflammatory activity was observed. These findings require further investigation to verify the promising concept of CCECC.     

Addition of dextran sulfate to blood cardioplegia attenuates reperfusion injury in a porcine model of cardiopulmonary bypass

Objective: Contact of blood with artificial surfaces and air as well as ischemia/reperfusion injury to the heart and lungs mediate systemic and local inflammation during cardiopulmonary bypass (CPB). Activation of complement and coagulation cascades leads to and accompanies endothelial cell damage. Therefore, endothelial-targeted cytoprotection with the complement inhibitor and endothelial protectant dextran sulfate (DXS, MW 5000) may attenuate CBP-associated myocardial and pulmonary injury. Methods: Eighteen pigs (DXS, n=10; phosphate buffered saline [PBS], n=8) underwent standard cardiopulmonary bypass. After aortic cross-clamping, cardiac arrest was initiated with modified Buckberg blood cardioplegia (BCP), repeated after 30 and 60min with BCP containing either DXS (300mg/10ml, equivalent to 5mg/kg) or 10ml of PBS. Following 30min reperfusion, pigs were weaned from CPB. During 2h of observation, cardiac function was monitored by echocardiography and invasive pressure measurements. Inflammatory and coagulation markers were assessed regularly. Animals were then sacrificed and heart and lungs analyzed. Results: DXS significantly reduced CK-MB levels (43.4+/-14.8ng/ml PBS, 35.9+/-11.1ng/ml DXS, p=0.042) and significantly diminished cytokine release: TNFalpha (1507.6+/-269.2pg/ml PBS, 222.1+/-125.6pg/ml DXS, p=0.0071), IL1beta (1081.8+/-203.0pg/ml PBS, 110.7+/-79.4pg/ml DXS, p=0.0071), IL-6 (173.0+/-91.5pg/ml PBS, 40.8+/-19.4pg/ml DXS, p=0.002) and IL-8 (304.6+/-81.3pg/ml PBS, 25.4+/-14.2pg/ml DXS, p=0.0071). Tissue endothelin-1 levels were significantly reduced (6.29+/-1.90pg/100mg PBS, 3.55+/-1.15pg/100mg DXS p=0.030) as well as thrombin-anti-thrombin formation (20.7+/-1.0mug/ml PBS, 12.8+/-4.1mug/ml DXS, p=0.043). Also DXS reduced cardiac and pulmonary complement deposition, neutrophil infiltration, hemorrhage and pulmonary edema (measured as lung water content, 81+/-3% vs 78+/-3%, p=0.047), indicative of attenuated myocardial and pulmonary CPB-injury. Diastolic left ventricular function (measured as dp/dt(min)), pulmonary artery pressure (21+/-3mmHg PBS, 19+/-3mmHg DXS, p=0.002) and right ventricular pressure (21+/-1mmHg PBS, 19+/-3mmHg DXS p=0.021) were significantly improved with the use of DXS. Conclusions: Addition of DXS to the BCP solution ameliorates post-CPB injury and to a certain extent improves cardiopulmonary function. Endothelial protection in addition to myocyte protection may improve post-CPB outcome and recovery.     

Endothelial apoptosis and circulating endothelial cells after bypass grafting with and without cardiopulmonary bypass.

OBJECTIVE: We compared profiles of the numbers of circulating endothelial cells (CEC) and the apoptosis-inducing capacity of serum samples on human endothelial cells (hEC) in on-pump and off-pump coronary artery bypass grafting (CABG) patients. METHODS: Blood samples from 30 patients undergoing CABG (randomly assigned to two groups: 15 patients off-pump and 15 on-pump (cardiopulmonary bypass, CPB)) were collected after induction of anesthesia (preoperatively), at weaning from CPB/end of bypass grafting (0 h), and 1, 6, 12, 24, and 48 h afterwards. CEC were isolated with immunomagnetic anti-CD146-coated Dynabeads, and counted in a Nageotte chamber. The apoptosis-inducing activity of serum samples on hEC was examined by a tissue culture assay system. Apoptotic and normal cells were identified using phase contrast/fluorescence microscopy after DNA dye staining. RESULTS: CEC numbers and proportions of apoptotic hEC were significantly elevated during and after surgery in both groups (p<0.01). Compared with the on-pump group, CEC and proportions of apoptotic hEC were significantly lower (p=0.04 and p=0.03, respectively) in patients having CABG performed off-pump. Starting at comparable baseline levels, the mean CEC-number was highest at 6h postoperatively with 81.9 ml(-1) (range, 44-141) for on-pump patients and 63.3 ml(-1) (range, 48-105) for off-pump patients. hEC apoptosis peaked also at T4: 16.5+/-2.8% versus 11.3+/-2.2%. In both groups, CEC numbers and proportions of endothelial apoptosis were still elevated at 48 h after surgery. CONCLUSION: The number of circulating endothelial cells and apoptotic endothelial cell death are markers of endothelial activation and damage during CABG. This study provides evidence that CABG with the use of CPB in comparison to OPCAB surgery is associated with a significantly more pronounced endothelial response in the immediate postoperative period.     

Synergistic induction of IL-10 by hypertonic saline solution and lipopolysaccharides in murine peritoneal macrophages

BACKGROUND: Liver injury after ischemia/reperfusion is an important cause of morbidity in surgical patients. We have shown that the preconditioning of animals that were subjected to liver ischemia/reperfusion with hypertonic saline solution (HTS) prevented injury by inhibiting Kupffer cell tumor necrosis factor (TNF) production. We postulated that the induction of anti-inflammatory interleukin-10 (IL-10) by HTS might contribute to protection. METHODS: Murine thioglycolate--elicited peritoneal exudative macrophages (PEMs) were used to model the effects of HTS on IL-10 release from Kupffer cells. Cells were preconditioned with 500 mOsm HTS (or isotonic saline medium) for 2 hours and then stimulated with lipopolysaccharide (LPS; 1 microg/mL) or vehicle for 4 hours under isotonic conditions. TNF-alpha and IL-10 were measured in the culture supernatant by enzyme-linked immunosorbent assay; TNF, IL-10, and SOCS-3 messenger RNA expression were assessed by Northern blot. NF-kappa B activation was examined by electrophoretic mobility shift assay and Western blot for I kappa B degradation. RESULTS: In the absence of LPS, isotonic medium--and HTS-pretreated PEMs produced little IL-10 (24.9 +/- 66.0 and 0 pg/mL, respectively); however, stimulation of PEMs with LPS increased IL-10 (134.9 +/- 72.2 pg/mL). Preconditioning with HTS significantly augmented LPS-induced IL-10 production, resulting in a 2-fold increase in IL-10 compared with the isotonic solution LPS group (270.7 +/- 106.8 pg/mL; P <.01). HTS alone increased IL-10 mRNA levels and markedly augmented levels induced by LPS alone. To determine whether IL-10 accounted for HTS-induced TNF inhibition, cells from IL-10 knockout animals were studied. A lack of IL-10 did not reverse the inhibitory effect of HTS on LPS-induced TNF. NF-kappa B activation was the same in HTS-and isotonic solution--pretreated groups after LPS. CONCLUSIONS: HTS augments IL-10 induction by LPS at the gene level. Although TNF is reduced, it is not causally related to increased IL-10 or altered NF-kappa B signaling. HTS might exert its beneficial effects by independently modulating pro- and anti-inflammatory molecules, accounting for the potent immunomodulation exerted by HTS in vivo.     

Hepatocyte growth factor and interleukin-6 in combination with prostate volume are possible prostate cancer tumor markers in patients with gray-zone PSA levels

The aim was to assess whether hepatocyte growth factor (HGF) and interleukin (IL)-6 in combination with prostate volume are able to accurately detect prostate cancer in patients with gray-zone prostate-specific antigen (PSA) levels. A total of 159 patients with PSA levels of <10 ng ml(-1) were enrolled. Forty-two (35.3%) were diagnosed with prostate cancer, whereas 117 (64.7%) had no cancer and were used as benign group. HGF and IL-6 density (HGFD and IL-6D, respectively) values were calculated by dividing serum HGF and IL-6 levels with prostate volume. Median IL-6 (2.3 pg ml(-1)) levels for the prostate cancer group were significantly higher than those for the benign group before adjustment for age (1.7 pg ml(-1)) (P=0.0098). After age adjustments, median IL-6 (2.17 pg ml(-1)), HGFD (0.00972 ng ml(-1) cm(-3)), and IL-6D (0.0848 pg ml(-1) cm(-3)) values for the prostate cancer group were significantly higher than those for the benign group (IL-6, 1.78 pg ml(-1); HGFD, 0.00732 ng/ml/cc; and IL-6D, 0.049 pg/ml/cc; P=0.0416, 0.007 and 0.0005, respectively). In receiver operating characteristic analyses, the areas under the curves for HGFD (0.64) and IL-6D (0.68) were significantly greater than those for HGF (0.52) and IL-6 (0.61) (P=0.0006 and 0.019, respectively). With an HGFD cutoff value of 0.00392 ng ml(-1) cm(-3) (sensitivity=100%, specificity=11%), 11.1% of the benign group were able to avoid unnecessary biopsies without missing prostate cancer. HGF and IL-6 levels in combination with prostate volume were shown to be useful parameters for prostate cancer screening in patients with gray-zone PSA levels.     

Cytokine response to surgical stress: comparison of pure laparoscopic, hand-assisted laparoscopic, and open nephrectomy

BACKGROUND AND PURPOSE: Laparoscopic surgery has been shown to induce less immune suppression than open surgery, presumably because there is less tissue trauma, a factor that may impact oncologic-disease control. The objective of this study was to compare the cytokine and stress response associated with pure laparoscopic, hand-assisted laparoscopic (HAL), and open nephrectomy. MATERIAL AND METHODS: Fifteen female farm pigs (45-50 kg) underwent transperitoneal laparoscopic, handassisted (HAL), or open nephrectomy (N = 5 in each group). At 1, 4, 24, and 48 hours post-nephrectomy, blood and peritoneal fluid samples were collected for measurement of tumor necrosis factor (TNF) alpha, interleukin (IL)-1beta, and IL-6 using enzyme-linked immunosorbent assay (ELISA) techniques. Body temperature and serum glucose and cortisol were also measured. RESULTS: No evidence of perioperative infection was detected in any animal through temperature and glucose monitoring. Operating time and blood loss were comparable among the three groups. Peak serum cortisol concentrations were significantly higher in the HAL group than in the pure laparoscopic group at 24 hours (P = 0.02). Serum TFNalpha concentrations were significantly lower in the pure laparoscopy group (40 +/- 6 pg/mL) than in the HAL and open-nephrectomy groups (81 +/- 6 pg/mL and 83 +/- 17 pg/mL, respectively; P < 0.05), although no differences between groups were found in the serum IL-1beta and IL-6 concentrations. Peritoneal IL-1beta was significantly higher in the HAL than in the open-nephrectomy group (2993 +/- 507 pg/mL and 733 +/- 185 pg/mL, respectively; P = 0.05). Peritoneal IL-6 was significantly lower in the pure laparoscopy group (694 +/- 234 pg/mL) than in the open-surgery group (1668 +/- 312 pg/mL) (P = 0.04). CONCLUSION: Pure laparoscopic surgery in pigs elicits a less-robust cytokine response than HAL or open nephrectomy with respect to serum TNFalpha and peritoneal IL-6 concentrations, perhaps reflecting less impairment of the immune system. Clinical confirmation is required, and the implications with regard to oncologic tumor surveillance in humans require further study.