Bacterial Load Associated With Tunneled Dialysis Catheters in Symptom-Free Hemodialysis Patients.

OBJECTIVE: This study aimed to evaluate the rate of asymptomatic bacterial infection of tunneled dialysis catheters (TDCs) removed due to maturation of native arteriovenous fistula (nAVF) or catheter dysfunction in hemodialysis patients with no clinically apparent infection. MATERIALS AND METHODS: A total of 229 patients (43.2% [n = 99] female and 56.8% [n = 130] male), who underwent hemodialysis through a TDC, were included in this study. Tip cultures of TDCs removed in an operating room and under sterile conditions were collected. All patients were asymptomatic for catheter infection and had not received antibiotic therapy for the last month. RESULTS: The median duration of catheterization was 80 days (min: 5, max: 2880). Bacterial growth was observed in a total of 62 (27.1%) patients. The most common microorganisms were Staphylococcus epidermidis and Staphylococcus aureus. The asymptomatic infection rate was highest in catheters placed through the right and left subclavian veins; however, this was not statistically significant due to the small number of patients. Placement and usage time of TDCs were found to be the most significant factors for bacterial growth in the catheter tip culture (P < .001). CONCLUSION: Prolonged duration and use of the catheter is significant in terms of bacterial load. The use of TDC as vascular access in renal replacement therapy should be avoided as much as possible.

The Effects of Amino Acids Enriched Del Nido Cardioplegia on Myocardial Leucocyte Accumulation and Ventricular Functions in Patients Undergoing Coronary Artery Bypass Grafting Surgery.

BACKGROUND: One of the main sources of ischemia/reperfusion injury (IRI) and release of free oxygen radicals (FORs) during extracorporeal circulation (ECC) during cardiac surgery is neutrophils. In this study, we investigated the potential effects of our modification of del Nido cardioplegia (mDNC) (amino acids enriched del Nido cardioplegia) on myocardial polymorphonuclear leucocyte (PMNL) accumulation. We also compared the effects of our mDND and classical del Nido cardiplegia (cDNC) on ventricular contractile functions in coronary artery bypass grafting (CABG) surgery. PATIENTS AND METHODS: Our study included 100 isolated CABG patients with similar characteristics, including age, gender, preoperative medications, diabetes, hypertension, and left ventricular ejection fraction (LVEF). The patients were divided into two groups. Amino acids supplemented del Nido cardioplegia (L-aspartate and L-glutamate at a dose of 13 milimol/L) in 50 patients (study group, G1). In the remaining 50 patients, we used a classical del Nido cardioplegic solution (cDNC) (control group, G2). Myocardial Tru-Cut biopsy from the right ventricle was taken before the institution of ECC and after weaning from ECC in all patients. Cardiac troponine-I (cTn-I), tumor necrosis factor-alpha (TNF-Alpha), Pro-Brain Natriuretic Peptide (Pro-BNP), and lactate levels were measured pre- and postoperatively. Invasive monitoring was performed to provide the left ventricular functions in both groups in the operating room and noted by a blinded anaesthesiologist. RESULTS: Five patients died post-surgery (5%) (two from SG and three from CG (P = .67), due to low cardiac output syndrome or multiorgan failure. At the postoperative period, cardiac output (CO) and stroke volume index (SVI) was higher in mDNC (mean ± SDS; 32.1 ± 7 versus 22.2 ± 6.9 mL/min/m² (P < .001). CI was significantly higher in mDNC after surgery (3.10 ± 0.76 versus 2.40 ± 0.30L/min/m² (P = .002). Ten patients (20%) in mDNC and 16 patients (32%) in cDNC required inotropic support (P < .001). The postoperative inotropic requirement was less in mDNC (6.1 ± 1.8 mg/kg versus 9.2 ± 1.9 mg/kg, P < .004). Blood gas analyses from the coronary sinus showed that myocardial acidosis was more severe in the control group [pH (0.10 ± 0.09 versus 0.054 ± 0.001; P = .34)]. Blood lactate levels were significantly high in the control group (1.01 ± 0.007 mmol/L versus 1.92 ± 0.35 mmol/L) (P = .22). No difference was found when compared with cardioplegia volume in the mDNC and cDNC groups (mDNC= 990.00 ± 385 mL in DNC = 960 ± 240 mL, P = .070). An aortic cross-clamp time in the mDNC and cDNC groups were 88.4 ± 8.9 min, and 93 ± 11 min, (P = .76), but cardiopulmonary bypass time was significantly low in mDNC (mDNC = 98.3 ± 22.5 min, DNC = 126 ± 19.5 min, P = .0020). TNF-Alpha and Pro-BNP levels in patients received mDNC were significantly low (P = .022). Postoperative cardiac enzyme levels (creatine kinase-MB and high sensitive troponin-I) were significantly low in the mDNC group (P = .0034). Myocardial biopsy results showed that myocardial PMNL accumulation was significantly high in the control group (P = .001). The amount of inotropic agent use was significantly high in the control group (P = .003). After weaning from ECC, the left ventricular stroke work index (LVSWI), cardiac index (CI), and heart rate (HR) were significantly high in the study group (P = .032; P = .002; P = .01). Postoperative blood and blood products requirements were significantly low in the mDNC group (P = .002). At pre-discharge echocardiography, the mDNC group demonstrated significantly higher ventricular ejection fraction (37.9 ± 4.3% and 29.7 ± 3.8%, respectively (P = .003). CONCLUSION: Our study findings show that glutamate-aspartate supplemented del Nido cardioplegia significantly decrease myocardial PMNL accumulation with reduced release of biochemical markers, including cardiac troponin-I, TNF-alpha, and Pro-Bnp. Our study results demonstrated that amino acids supplementation in del Nido cardioplegia has some advantages in CABG patients, including the decrease of perioperative myocardial infarction and increase significantly the left ventricular functions including ventricular SVI and CI.

Procedure and Clinical Success of Drug-Coated Balloon Fistuloplasty of the Drainage Vein in Dysfunctional Native Arteriovenous Fistulas.

PURPOSE: Native arteriovenous fistulas (AVFs) are the most effective vascular access (VA) for haemodialysis. We aimed to evaluate the results of balloon angioplasty (fistuloplasty) from drainage vein performed for the treatment of AVF dysfunction in haemodialysis patients and examine potential patient and AVF-associated factors that might affect such results. METHODS: This is a nonrandomized, retrospective, and single-centred study. A total of 105 balloon fistuloplasties were performed for dysfunctional AVFs of 82 haemodialysis patients. Patients were treated with a drug-coated balloon according to standard procedures. Evaluations were performed by physical examinations and if needed by color Doppler imaging in every 6 months. The primary endpoint was patency by balloon fistuloplasty. Patency was evaluated clinically by detecting the thrill in AVF and by the adequacy of the dialysis. Multidimensional scaling (MDS) technique was used as a method for the statistical analysis. RESULTS: The success of the procedure after the first attempt was 85.3% with 70 patients. Patency in the 6th, 12th, 18th, and 24th months were 63 (76.8%), 60 (73.1%), 53 (64.6%), and 44 (54%), respectively. The procedure was considered successful when the thrill was detected in AVF and when dialysis was adequate. The statistical analysis by MDS revealed that patients' age was the most effective factor acting on the procedure success followed by the age of AVF. Other patient-associated and AVF-associated factors were not found as effective statistical evaluation. CONCLUSIONS: Haemodialysis through native AVFs with restored functionality contributes positively to the life span and the quality of life of the patient. Probably, advanced age and high fistula age are unfavourable factors leading to the development of neointimal hyperplasia and venous stenosis. Balloon fistuloplasty of the draining vein is an effective and safe method regardless of patient age and the age of AVF.

Cardiac Output Values and Correlation of Renal Injury with Neutrophil Gelatinase-Associated Lipocalin Levels in Off-Pump Coronary Artery Bypass Patients.

OBJECTIVE: To investigate the correlation between cardiac output values and renal neutrophil gelatinase-associated lipocalin (NGAL) levels as a biomarker of renal ischemia. METHODS: Forty patients, who underwent off-pump coronary artery bypass (OPCAB) surgery and in whom the positioning of the heart was fixed with simple suspension sutures without a mechanical stabilizer, were included in the study. Continuous cardiac output (CO) measurements were recorded using the arterial pressure waveform analysis method (FloTrac sensor system) in the perioperative period. CO was recorded every minute during non-anatomical cardiac positioning for left anterior descending artery (LAD), diagonal artery (D), circumflex artery (Cx), and right coronary artery (RCA) bypasses. Serum NGAL samples were analyzed in the preoperative, perioperative, and postoperative periods. RESULTS: The CO values measured at various non-anatomical cardiac positions during distal anastomosis for LAD, D, Cx, and RCA were significantly lower than pre- and postoperative values measured with the heart in normal anatomical position (3.45±0.78, 2.9±0.71, 3.11±0.56, 3.19±0.81, 5.03±1.4, and 4.85±0.78, respectively, P=0.008). There was no significant difference between CO values measured at various non-anatomical cardiac positions during distal anastomosis. Although there was no significant correlation between NGAL levels and age, duration of surgery, preoperative CO, D-CO, RCA-CO, and postoperative CO measurements, there was a significant correlation between NGAL levels and LAD-CO (P=0.044) and Cx-CO (P=0.018) at the postoperative 12th hour. CONCLUSION: Full revascularization may be achieved by employing the OPCAB technique while using simple suspension sutures without a mechanical stabilizer and by providing safe CO levels and low risk of renal ischemia.

Cardiac output values and correlation of renal injury with neutrophil gelatinase-associated lipocalin levels in off-pump coronary artery bypass patients

Abstract Objective: To investigate the correlation between cardiac output values and renal neutrophil gelatinase-associated lipocalin (NGAL) levels as a biomarker of renal ischemia. Methods: Forty patients, who underwent off-pump coronary artery bypass (OPCAB) surgery and in whom the positioning of the heart was fixed with simple suspension sutures without a mechanical stabilizer, were included in the study. Continuous cardiac output (CO) measurements were recorded using the arterial pressure waveform analysis method (FloTrac sensor system) in the perioperative period. CO was recorded every minute during non-anatomical cardiac positioning for left anterior descending artery (LAD), diagonal artery (D), circumflex artery (Cx), and right coronary artery (RCA) bypasses. Serum NGAL samples were analyzed in the preoperative, perioperative, and postoperative periods. Results: The CO values measured at various non-anatomical cardiac positions during distal anastomosis for LAD, D, Cx, and RCA were significantly lower than pre- and postoperative values measured with the heart in normal anatomical position (3.45±0.78, 2.9±0.71, 3.11±0.56, 3.19±0.81, 5.03±1.4, and 4.85±0.78, respectively, P=0.008). There was no significant difference between CO values measured at various non-anatomical cardiac positions during distal anastomosis. Although there was no significant correlation between NGAL levels and age, duration of surgery, preoperative CO, D-CO, RCA-CO, and postoperative CO measurements, there was a significant correlation between NGAL levels and LAD-CO (P=0.044) and Cx-CO (P=0.018) at the postoperative 12th hour. Conclusion: Full revascularization may be achieved by employing the OPCAB technique while using simple suspension sutures without a mechanical stabilizer and by providing safe CO levels and low risk of renal ischemia.

Clinical Outcomes after Biologic Graft Use for the Creation of Blalock-Taussig Shunt in Critically Ill Patients with Thrombophilia.

BACKGROUND: The modified systemic to pulmonary artery shunt (mSPS) is an effective palliative procedure in children with cyanotic congenital heart disease (CCHD) who are not suited for total correction. Early graft failure related to hereditary thrombophilic disorder is one cause of mortality. The aim of this study is to compare the clinical outcomes and rate of graft failure after mSPS in cyanotic infants with hereditary thrombophilia using bovine mesenteric venous graft (BMVG) and polytetrafluoroethylene (PTFE). METHODS: 60 cyanotic patients (28 neonates, mean age 19 ± 11.3 days; range 1 to 27) who had thrombophilic risk factors were divided into 2 groups: BMVG (n = 30) and PTFE (n = 30). Preoperative thrombophilic factors were measured for each patient. The most common thrombophilic factors were protein C and S deficiency and Factor V Leiden mutation. We also investigated D-dimer, positivity of prothrombin G20210A, factor XII and antithrombin III deficiency, and homocysteinemia in both groups. The mean age of patients was 4.6 ± 1.09 months (range 1 day to 6 months) in the BMVG group and 3.9 ± 1.02 months (range 2 days to 9 months) in the PTFE group (P = .67). mSPS procedures were performed via left thoracotomy (n = 19 in the BMVG group and n = 22 in the PTFE group) or right anterior thoracotomy (n = 3 in the BMVG group and n = 3 in the PTFE group). Median sternotomy was performed to create a central shunt in 8 neonates in the BMVG group. In the PTFE group, we performed a central shunt in 5 patients via median sternotomy. Low molecular weight heparin in combination with acetylsalicylic acid (aspirin) were administered after surgery in both groups. The patients received aspirin combined with warfarin (Coumadin) after being discharged from hospital. We performed revision surgery to observe whether any patient had a significant drop in saturation with inaudible mSPS murmur. RESULTS: 7 patients died early after surgery (n = 2 in the BMVG group [6.6%] and n = 5 in the PTFE group [16.5%]; P = .022). 53 patients were discharged home in good clinical condition. Early graft thromboses were observed in 2 patients in the BMVG group (6.6%) and 8 patients in the PTFE group (26.6%) (P = .001). In a case from the BMVG group, the reason for graft thrombosis was entanglement of the graft. Revision surgery was performed successfully without any complication. Cil et collegues has been reported a successful percutaneous balloon angioplasty after an acute thrombosis of BMVG previously [Cil 2010]. In another patient who had acute BMVG thrombosis, we performed transluminal graft angioplasty using successful thrombolytic administration in the catheterization laboratory. There were no complications due to graft materials such as hematoma, seroma, or infection in the BMVG group. Bleeding from the needle hole was seen in 1 patient in the BMVG group. PTFE thrombosis developed in 3 patients within 24 hours (10%). We detected total or partial PTFE graft thrombosis in 5 patients during the follow-up period (20%). Revision surgeries in 3 patients were performed immediately after diagnosis. Transluminal balloon angioplasty combined with thrombolysis was performed in infants with partial or total PTFE occlusion in 5 patients. In the PTFE group, perigraft seroma (n = 5 [16.6%)] and hematoma (n = 2 [6.6%]) were detected. We performed revision surgery because of bleeding from the needle hole in 3 patients in the PTFE group (10%) in the early period after surgery. We detected a graft infection in 1 patient (3.3%) 6 months after surgery in the PTFE group. The rate of overall complications including pseudoaneurysm, seroma formation, graft infection, or partial or total graft occlusion in the early and follow-up periods was 6.6% in the BMVG group and 53.3% in the PTFE group (P = .0001). The rate of freedom from shunt failure was 92.6% ± 2.1% and 76.2% ± 4.8% during follow-up in BMVG and PTFE groups, respectively (P = .034). The rate of shunt-related mortality was 10.7% (n = 3) in the BMVG group and 20% in the PTFE group (P = .01). Regular physical examinations, transcutaneous oxygen saturation, and echocardiographic study were performed for shunt control during follow-up. Shunt occlusion or thrombosis was not seen in the BMVG group; 5 patients in the PTFE group (20%) had shunt occlusion during follow-up (P = .001). CONCLUSION: Our study shows that BMVG, as a biological material, may be used as an alternative material for creating mSPS. It decreases postoperative life-threatening complications after shunt procedures, including graft thrombosis, bleeding from the needle hole, perigraft hematoma, and seroma in patients with hereditary thrombophilia. To our knowledge, we report the first clinical comparison of the 2 grafts in our case series with thrombophilic risk factors.

The effect of iloprost and sildenafil, alone and in combination, on myocardial ischaemia and nitric oxide and irisin levels.

AIM: Insufficient oxygen supply to organs and tissues due to reduced arterial or venous blood flow results in ischaemia, during which, although ATP production stops, AMP and adenosine continue to be produced from ATP. The fate of irisin, which causes the production of heat instead of ATP during ischaemia, is unknown. Iloprost and sildenafil are two pharmaceutical agents that mediate the resumption of reperfusion (blood supply) via vasodilatation during ischaemic conditions. Our study aimed to explore the effects of iloprost and sildenafil on irisin levels in the heart, liver and kidney tissues and whether these pharmaceutical agents had any impact on serum irisin and nitric oxide levels in rats with induced experimental myocardial ischaemia. METHODS: The study included adult male Sprague-Dawley rats aged 10 months and weighing between 250 and 280 g. The animals were randomly allocated to eight groups, with five rats in each group. The groups were: sham (control), iloprost (ILO), sildenafil (SIL), ILO + SIL, myocardial ischaemia (MI), MI + ILO, MI + SIL and MI + ILO + SIL. The treatment protocols were implemented before inducing ischaemia, which was done by occluding the left coronary artery with a plastic ligature for 30 minutes. Following the reperfusion procedure, all rats were sacrificed after 24 hours, and their heart, liver and kidney tissues and blood samples were collected for analyses. An immunohistochemical method was used to measure the change in irisin levels, the ELISA method to quantify blood irisin levels, and Griess' assay to determine nitric oxide (NO) levels in the serum and tissue. Myocardial ischaemia was confirmed based on the results of Masson's trichrome staining, as well as levels of troponin and creatine kinase MB. RESULTS: Irisin levels in biological tissue and serum dropped statistically significantly in the ischaemic group (MI), but were restored with ILO and SIL administration. Individual SIL administration was more potently restorative than individual ILO administration or the combined administration of the two agents. NO level, on the other hand, showed the opposite tendency, reaching the highest level in the MI group, and falling with the use of pharmaceutical agents. CONCLUSIONS: Individual or combined administration of ILO and SIL reduced myocardial ischaemia and NO levels, and increased irisin levels. Elevated levels of irisin obtained by drug administration could possibly contribute to accelerated wound recovery by local heat production. Sildenafil was more effective than iloprost in eliminating ischaemia and may be the first choice in offsetting the effects of ischaemia in the future.

Levosimendan Use Increases Cardiac Performance after Coronary Artery Bypass Grafting in End-Stage Renal Disease Patients.

BACKGROUND: The effect of levosimendan on myocardial performance has not been studied in dialysis-dependent end-stage renal disease patients who have undergone coronary artery bypass grafting (CABG) surgery. Our aim was to investigate the effect of levosimendan on postoperative hemodynamic effects in end-stage renal disease patients undergoing CABG operation. METHODS: We performed 58 elective isolated CABG operations in end-stage renal disease patients. The study group received levosimendan at a slow bolus dose of 3 µg/kg, followed by a 24-hour infusion of 0.03-0.05 µg/kg/kg/min. (study group [SG]: n = 25). The remaining patients received a placebo (control group [CG]: n = 33). The mean left ventricular ejection fraction of both groups was similar (44.6 ± 55.4% versus 42.8 ± 53.9%). Hemodynamic data were collected at the end, at 1 hour after CPB, and thereafter at 6, 12, and 24 hours in the ICU. Preoperatively, at the end of the operation, at 1 hour after CPB, and thereafter at 6, 12, and 24 hours in the ICU, blood samples from the peripheral vein were collected for cardiac troponin-I (c-TnI) and lactate levels. Norepinephrine if needed started during the rewarming period in both groups. RESULTS: One patient in SG (4%) and 4 patients (12.1%) in CG died postoperatively (P < .01). Cardiac output and cardiac index values did not change early after weaning from extracorporeal circulation, and they were nearly similar during the next 6 hours in both groups. In SG, cardiac output and cardiac index significantly improved at 6 hours, and were stable at the end of 24 hours (P < .001). Hemodynamic parameters were nearly similar after the operation, and did not change significantly at the end of 24 hours in CG. Hemodynamic improvement caused a significant reduction in systemic and pulmonary artery vascular resistance index in SG (P < .002). Pulmonary capillary wedge pressure decreased significantly in SG (P < .034). Cumulative inotrope dose requirement and intraaortic balloon pump use were significantly lower in SG. In addition, blood lactate and cTnI levels were significanly lower in SG (P < .044). CONCLUSION: No important adverse effect was detected during levosimendan infusion. Because levosimendan at a dose of 0.03-0.05 µg/kg/min increased myocardial performance significantly in the postoperative period, it can be used safely in end-stage renal disease patients undergoing isolated CABG. The requirement of vasopressors were lower in SG.

The Effects of Levosimendan and Sodium Nitroprusside Combination on Left Ventricular Functions After Surgical Ventricular Reconstruction in Coronary Artery Bypass Grafting Patients.

OBJECTIVE: The aim of our study was to research the effects of levosimendan (LS) and sodium nitroprusside (SNP) combination on systolic and diastolic ventricular function after coronary artery bypass grafting (CABG) who required endoventricular patch repair (EVPR). PATIENTS AND METHODS: We studied 70 patients with ischemic dilated cardiomyopathy. LS and SNP combination was administered in 35 patients (study group, SG). In the remaining patients, normal saline solution was given (placebo group, PG). Levosimendan (10µgr/kg) started 4 h prior to operation and we stopped LS before the initiation of extracorporeal circulation (ECC). During the rewarming period, we started again levosimendan (10µgr/kg) in combination with SNP (0.1-0.2 µgr/kg/min). If mean blood pressure decreased by more than 25% compared with pre-infusion values, for corrected of mean arterial pressure, the volume loading was performed using a 500 ml ringer lactate. Hemodynamic variables, inotrophyc requirement, and laboratory values were recorded. RESULTS: Five patients died (7.14%) post-surgery (one from SG and 4 from PG) due to low cardiac out-put syndrome (LOS). At the postoperative period, cardiac output and stroke volume index was higher in SG (mean±sd;29.1±6.3 vs. 18.4±4.9 mL/min(-1)/m(-2) (P<0.0001)). Stroke volume index (SVI) decreased from 29±10mL/m(2) preoperatively to 22±14mL/m(2) in the early postoperative period in group 1. This difference was statistically significant (P=0.002). Cardiac index was higher in SG (320.7±37.5 vs. 283.0±83.9 mL/min(-1)/m-(2) (P=0.009)). The postoperative inotrophyc requirement was less in SG (5.6±2.7 vs. 10.4±2.0 mg/kg, P< 0.008), and postoperative cardiac enzyme levels were less in SG (P< 0.01). Ten patients (28.5%) in SG and 21 patients (60%) in PG required inotrophyc support (P<0.001). We used IABP in eight patients (22.8%) in SG and 17 patients (48.5%) in CG (P=0.0001). CONCLUSION: This study showed that LS and SNP combination impressive increase in left ventricular systolic and diastolic functions including LVEF. The use of this combination achieved more less inotrophics and IABP requirement. We therefore suggest preoperative and peroperative levosimendan and SNP combination.

Left main coronary disease: improved early outcomes after off-pump coronary artery bypass grafting in high-risk patients.

BACKGROUND: Left main coronary artery (LMCA) stenosis is a risk factor in coronary artery bypass grafting (CABG). Although improved outcomes of off-pump CABG have been well documented, LMCA stenosis is often perceived as a contraindicationfor off-pump CABG. In this study, we compared on-pump and off-pump techniques in high-risk patients with LMCA disease. AIM: Documentation of safety and feasibility of off-pump CABG in patients with LMCA disease. METHODS: One hundred ninty nine patients with LMCA disease and a EuroScore ≥ 5 were operated upon between 2007 and 2010. One hundred patients (Group I) were operated upon using off-pump techniques, while 99 (Group II) were operated upon using conventional on-pump techniques. Perioperative variables and outcomes at first six months were compared. RESULTS: Despite higher mean age and EuroScore (70.9 ± 4.8 vs. 65.6 ± 7.9, p < 0.001, and 6.09 ± 0.8 vs. 5.31 ± 0.68,p < 0.001, respectively), and lower ejection fraction (41.4 ± 7.3 vs. 49.0 ± 6.2, p < 0.001), hospital mortality (1% vs. 6.1%,p = 0.065), postoperative inotropic support (9% vs. 48.4%, p < 0.001), blood loss (680.6 ± 265.0 vs. 847.2 ± 382, p < 0.001) and transfusions of blood (0.57 ± 0.79 U vs. 1.49 ± 0.82 U, p < 0.001), and hospital stay (6.57 ± 2.04 vs. 7.68 ± 3.44,p = 0.006) were lower in Group I. In both groups, mean number of distal anastomoses and completeness of revascularisation were similar. CONCLUSIONS: Using the off-pump technique is safe and improves postoperative early outcomes in high-risk patients with LMCA disease.