[Sodium balance and peritoneal ultrafiltration in refractory heart failure].

About 5% of patients with heart failure (HF) reach the end-stage of disease, becoming refractory to therapy. The clinical course of end-stage HF is characterized by repeated hospitalizations, severe symptoms, and poor quality of life. Peritoneal ultrafiltration (PUF), removing water and sodium (Na+), can benefit patients with end-stage HF. However, effects on fluid and electrolyte removal have not been fully characterized. In this pilot study in patients with chronic HF and moderate chronic renal failure, we evaluated the effects of water and sodium removal through PUF on ventricular remodeling, re-hospitalization, and quality of life. Patients with end-stage HF (NYHA class IV, ≥3 HF hospitalization/year despite optimal therapy), not eligible for heart transplantation underwent peritoneal catheter positioning and began a single-day exchange with icodextrin at night (n=6), or 1-2 daily exchanges with hypertonic solution (3.86%) for 2 hours with 1.5-2 L fill volume (n=3). At baseline, average ultrafiltration was 500±200 ml with icodextrin, and 700±100 ml with hypertonic solution. Peritoneal excretion of Na+ was greater with icodextrin (68±4 mEq/exchange) compared to hypertonic solution (45±19 mEq/exchange). After a median 12-month follow-up, rehospitalizations decreased, while NYHA class and quality of life (by Minnesota Living with HF questionnaire), improved. In end-stage HF patients, PUF reduced re-hospitalization and improved quality of life. It can be an additional treatment to control volume and sodium balance.

Spondylodiscitis in hemodialysis patients: a new emerging disease? Data from an Italian Center.

Hemodialysis (HD) patients are at high risk for infectious complications such as spondylodiscitis. The aim of this retrospective study was to evaluate the cases of infective spondylodiscitis occurred between May 2005 and October 2019 among HD patients at our center. In 14 years, there were 9 cases (mean age 69±12 years). The main comorbidities found were diabetes mellitus (55.6% of patients), hypertension (55.6%), bone diseases (22.2%), cancer (11.1%) and rheumatoid arthritis treated with steroids (11.1%). The clinical onset included back pain (100% of cases), fever (55.6%), neurological deficits (33.4%), leukocytosis (55.6%) and elevated CRP level (88.9%). Most cases were diagnosed by magnetic resonance imaging (66.7%) with more frequent involvement of lumbar region (77.8%). Blood cultures were positive in five patients (mostly for S. aureus); three of them used catheters as vascular access and, in two cases, their removal was necessary. The mean time interval between the onset of symptoms and the diagnosis was 34±42 days. All patients received antibiotic treatment for a mean duration of 6 weeks; most cases were initially treated with vancomycin or teicoplanin plus ciprofloxacin. Most patients (77.8%) recovered after a mean of 3.5 months; one patient had a relapse after 2 years and one patient had long-term neurologic sequelae. Infective spondylodiscitis in HD must be suspected in the presence of back pain, even in the absence of fever or traditional risk factors. An early diagnosis could improve the outcome. Close monitoring of vascular access, disinfection procedures and aseptic techniques are important to avoid this complication.

Case report: the thoracoscopic surgery in peritoneal-pleural leakage. A valid therapeutic strategy.

Pleuro-peritoneal leakage is an uncommon complication of peritoneal dialysis (PD). In this study, we report the case of a male patient (age 83), treated with PD (daytime single-exchange). In October 2019, hospitalization was necessary due to dyspnoea and a reduction of peritoneal ultrafiltration. A right pleural leakage resulted at chest x-ray. A regression of the pleural leakage was immediately observed after interrupting PD. It was then performed a pleuro-peritoneal CT scan at baseline, followed by a second scan performed 4 hours after the injection of 2 L of isotonic solution with 100ml of contrast medium, which evidenced a pleuro-peritoneal communication. It was then decided to perform a video-assisted thoracoscopic surgery (VATS), that showed no evidence of diaphragm communication. It was then executed a pleurodesis using sterile talcum. The patient was released on the 3rd day, with a conservative therapy and a low-protein diet. After 2 weeks a new pleuro-peritoneal CT scan with contrast medium was executed. This time the scan evidenced the absence of contrast medium in the thoracic cavity. The patient then resumed PD therapy, with 3 daily exchanges with isotonic solution (volume 1.5 L), showing no complications. Concerning the treatment of pleuro-peritoneal leakage, VATS allows both the patch-repairing of diaphragmatic flaws and the instillation of chemical agents. In our case, VATS allowed the chemical pleurodesis which in turn enabled, in just 2 weeks of conservative treatment, the resuming of PD. In conclusion, this methodology is a valid option in the treatment of pleuro-peritoneal leakage in PD patients.

Acute effect of a peritoneal dialysis exchange on electrolyte concentration and QT interval in uraemic patients.

BACKGROUND: Hemodialysis (HD) sessions induce changes in plasma electrolytes that lead to modifications of QT interval, virtually associated with dangerous arrhythmias. It is not known whether such a phenomenon occurs even during peritoneal dialysis (PD). The aim of the study is to analyze the relationship between dialysate and plasma electrolyte modifications and QT interval during a PD exchange. METHODS: In 15 patients, two manual PD 4-h exchanges were performed, using two isotonic solutions with different calcium concentration (Ca++1.25 and Ca1.75++ mmol/L). Dialysate and plasma electrolyte concentration and QT interval (ECG Holter recording) were monitored hourly. A computational model simulating the ventricular action potential during the exchange was also performed. RESULTS: Dialysis exchange induced a significant plasma alkalizing effect (p < 0.001). Plasma K+ significantly decreased at the third hour (p < 0.05). Plasma Na+ significantly decreased (p < 0.001), while plasma Ca++ slightly increased only when using the Ca 1.75++ mmol/L solution (p < 0.01). The PD exchange did not induce modifications of clinical relevance in the QT interval, while a significant decrease in heart rate (p < 0.001) was observed. The changes in plasma K+ values were significantly inversely correlated to QT interval modifications (p < 0.001), indicating that even small decreases of K+ were consistently paralleled by small QT prolongations. These results were perfectly confirmed by the computational model. CONCLUSIONS: The PD exchange guarantees a greater cardiac electrical stability compared to the HD session and should be preferred in patients with a higher arrhythmic risk. Moreover, our study shows that ventricular repolarization is extremely sensitive to plasma K+ changes, also in normal range.

Exercise in Patients on Dialysis: A Multicenter, Randomized Clinical Trial.

Previous studies have suggested the benefits of physical exercise for patients on dialysis. We conducted the Exercise Introduction to Enhance Performance in Dialysis trial, a 6-month randomized, multicenter trial to test whether a simple, personalized walking exercise program at home, managed by dialysis staff, improves functional status in adult patients on dialysis. The main study outcomes included change in physical performance at 6 months, assessed by the 6-minute walking test and the five times sit-to-stand test, and in quality of life, assessed by the Kidney Disease Quality of Life Short Form (KDQOL-SF) questionnaire. We randomized 296 patients to normal physical activity (control; n=145) or walking exercise (n=151); 227 patients (exercise n=104; control n=123) repeated the 6-month evaluations. The distance covered during the 6-minute walking test improved in the exercise group (mean distance±SD: baseline, 328±96 m; 6 months, 367±113 m) but not in the control group (baseline, 321±107 m; 6 months, 324±116 m; P<0.001 between groups). Similarly, the five times sit-to-stand test time improved in the exercise group (mean time±SD: baseline, 20.5±6.0 seconds; 6 months, 18.2±5.7 seconds) but not in the control group (baseline, 20.9±5.8 seconds; 6 months, 20.2±6.4 seconds; P=0.001 between groups). The cognitive function score (P=0.04) and quality of social interaction score (P=0.01) in the kidney disease component of the KDQOL-SF improved significantly in the exercise arm compared with the control arm. Hence, a simple, personalized, home-based, low-intensity exercise program managed by dialysis staff may improve physical performance and quality of life in patients on dialysis.

Low vitamin K1 intake in haemodialysis patients.

BACKGROUND & AIMS: Vitamin K acts as a coenzyme in the γ-carboxylation of vitamin K-dependent proteins, including coagulation factors, osteocalcin, matrix Gla protein (MGP), and the growth arrest-specific 6 (GAS6) protein. Osteocalcin is a key factor for bone matrix formation. MGP is a local inhibitor of soft tissue calcification. GAS6 activity prevents the apoptosis of vascular smooth muscle cells. Few data on vitamin K intake in chronic kidney disease patients and no data in patients on a Mediterranean diet are available. In the present study, we evaluate the dietary intake of vitamin K1 in a cohort of patients undergoing haemodialysis. METHODS: In this multi-centre controlled observational study, data were collected from 91 patients aged >18 years on dialysis treatment for at least 12 months and from 85 age-matched control subjects with normal renal function. Participants completed a food journal of seven consecutive days for the estimation of dietary intakes of macro- and micro-nutrients (minerals and vitamins). RESULTS: Compared to controls, dialysis patients had a significant lower total energy intake, along with a lower dietary intake of proteins, fats, carbohydrates, fibres, and of all the examined minerals (Ca, P, Fe, Na, K, Zn, Cu, and Mg). With the exception of vitamin B12, vitamins intake followed a similar pattern, with a lower intake in vitamin A, B1, B2, C, D, E, folates, K1 and PP. These finding were confirmed also when normalized for total energy intake or for body weight. In respect to the adequate intakes recommended in the literature, the prevalence of a deficient vitamin K intake was very high (70-90%) and roughly double than in controls. Multivariate logistic model identified vitamin A and iron intake as predictors of vitamin K deficiency. CONCLUSIONS: Haemodialysis patients had a significantly low intake in vitamin K1, which could contribute to increase the risk of bone fractures and vascular calcifications. Since the deficiency of vitamin K intake seems to be remarkable, dietary counselling to HD patients should also address the adequacy of vitamin K dietary intake and bioavailability. Whether diets with higher amounts of vitamin K1 or vitamin K supplementation can improve clinical outcomes in dialysis patients remains to be demonstrated.

Fitness for entering a simple exercise program and mortality: a study corollary to the exercise introduction to enhance performance in dialysis (EXCITE) trial.

BACKGROUND/AIMS: In this corollary analysis of the EXCITE study, we looked at possible differences in baseline risk factors and mortality between subjects excluded from the trial because non-eligible (n=216) or because eligible but refusing to participate (n=116). METHODS: Baseline characteristics and mortality data were recorded. Survival and independent predictors of mortality were assessed by Kaplan-Meier and Cox regression analyses. RESULTS: The incidence rate of mortality was higher in non-eligible vs. eligible non-randomized patients (21.0 vs. 10.9 deaths/100 persons-year; P<0.001). The crude excess risk of death in non-eligible patients (HR 1.96; 95% CI 1.36 to 2.77; P<0.001) was reduced after adjustment for risk factors which differed in the two cohorts including age, blood pressure, phosphate, CRP, smoking, diabetes, triglycerides, cardiovascular comorbidities and history of neoplasia (HR 1.60; 95% CI 1.10 to 2.35; P=0.017) and almost nullified after including in the same model also information on deambulation impairment (HR 1.16; 95% CI 0.75 to 1.80; P=0.513). CONCLUSIONS: Deambulation ability mostly explains the difference in survival rate in non-eligible and eligible non-randomized patients in the EXCITE trial. Extending data analyses and outcome reporting also to subjects not taking part in a trial may be helpful to assess the representability of the study population.

Physical performance and clinical outcomes in dialysis patients: a secondary analysis of the EXCITE trial.

BACKGROUND/AIMS: Scarce physical activity predicts shorter survival in dialysis patients. However, the relationship between physical (motor) fitness and clinical outcomes has never been tested in these patients. METHODS: We tested the predictive power of an established metric of motor fitness, the Six-Minute Walking Test (6MWT), for death, cardiovascular events and hospitalization in 296 dialysis patients who took part in the trial EXCITE (ClinicalTrials.gov Identifier: NCT01255969). RESULTS: During follow up 69 patients died, 90 had fatal and non-fatal cardiovascular events, 159 were hospitalized and 182 patients had the composite outcome. In multivariate Cox models - including the study allocation arm and classical and non-classical risk factors - an increase of 20 walked metres during the 6MWT was associated to a 6% reduction of the risk for the composite end-point (P=0.001) and a similar relationship existed between the 6MWT, mortality (P<0.001) and hospitalizations (P=0.03). A similar trend was observed for cardiovascular events but this relationship did not reach statistical significance (P=0.09). CONCLUSIONS: Poor physical performance predicts a high risk of mortality, cardiovascular events and hospitalizations in dialysis patients. Future studies, including phase-2 EXCITE, will assess whether improving motor fitness may translate into better clinical outcomes in this high risk population.

Peritoneal ultrafiltration in refractory heart failure: a cohort study.

INTRODUCTION: Acutely decompensated heart failure (HF) in patients with diuretic resistance is often treated with extracorporeal ultrafiltration. Peritoneal ultrafiltration (PUF) has been proposed for the long-term management of severe HF after resolution of the acute episode. The aim of the present study was to evaluate the use of PUF in the treatment of chronic refractory HF in patients without end-stage renal disease. ♢ METHODS: This multicenter (10 nephrology departments throughout Italy) retrospective observational study included patients with severe HF refractory to maximized drug treatment. The patients were proposed for PUF because they had experienced at least 3 hospital admissions in the preceding year for acutely decompensated HF requiring extracorporeal ultrafiltration. ♢ RESULTS: Of the 48 study patients (39 men, 9 women; mean age 74 ± 9 years), 30 received 1 nocturnal icodextrin exchange, 5 required 2 daily exchanges, and 13 received 2 - 4 sessions per week of automated peritoneal dialysis. During the first year, renal function remained stable (initial: 20.8 ± 10.0 mL/min/1.73 m(2); end: 22.0 ± 13.6 mL/min/1.73 m(2)), while pulmonary artery systolic pressure declined to 40 ± 6.09 mmHg from 45.5 ± 9.18 mmHg (p = 0.03), with a significant concomitant improvement in New York Heart Association functional status. Hospitalizations decreased to 11 ± 17 days/patient-year from 43 ± 33 days/patient-year before the start of PUF (p < 0.001). The incidence of peritonitis was 1 episode in 45 patient-months. Patient survival was 85% at 1 year and 56% at 2 years. ♢ CONCLUSIONS: This study confirms the satisfactory results of using PUF for chronic HF in elderly patients.

High prevalence of vertebral fractures assessed by quantitative morphometry in hemodialysis patients, strongly associated with vascular calcifications.

Few studies have provided information on the prevalence of vertebral fractures (VFs) and their risk factors in hemodialysis patients. A multicenter, cross-sectional, observational study was carried out to assess the prevalence of VFs and vascular calcifications (VCs) in 387 hemodialysis patients (mean age 64.2 ± 14.1 years, 63 % males) and in a control group of 51 osteoporotic subjects. Biochemical tests included 25(OH) vitamin D, bone Gla protein (total and undercarboxylated), and total matrix Gla protein. Vertebral quantitative morphometry was carried out centrally for the detection of VF, defined as reduction by ≥20 % of one of the vertebral body dimensions. In the same radiograph, aortic and iliac VC scores were calculated. Prevalence of VF was 55.3 % in hemodialysis patients and 51.0 % in the control group. Multivariate analysis disclosed that male gender (59.8 vs. 47.6 %, p = 0.02; OR = 1.78, 95 % CI 1.15-2.75) and age (mean ± SD 66.7 ± 13.1 vs. 61.0 ± 14.7 years, p < 0.001; OR = 1.03, 95 % CI 1.01-1.05) were significantly associated with VF. The prevalence of aortic VC was significantly higher in hemodialysis patients than in controls (80.6 vs. 68.4 %, p = 0.001). The factors with the strongest association with VC, apart from atrial fibrillation, were serum 25(OH)vitamin D levels below 29 ng/mL for aortic VC (OR = 1.85, 95 % CI 1.04-3.29) and VF both for aortic (OR = 1.77, 95 % CI 1.00-3.14) and iliac (OR = 1.96, 95 % CI 1.27-3.04) VC. In conclusion, the prevalence of VF, especially in males, and VC, in both genders, is high in hemodialysis patients. VF is associated with VC. Vitamin D deficiency is also associated with VC. Further longitudinal studies are warranted to investigate fractures in renal patients.

[Incremental peritoneal dialysis: a common solution for different types of patients]. / La dialisi peritoneale incrementale: una soluzione comune per pazienti diversi.

It is still a matter of debate whether peritoneal dialysis should be initiated with a full dose regimen or with incremental doses. The use of low-dose dialysis is not always feasible, but it may have the advantages of improved quality of life and lower infective and metabolic complication rates. However, incremental peritoneal dialysis has to meet the minimal suggested adequacy targets in terms of depuration (Kt/V, creatinine clearance), ultrafiltration, and electrolyte balance. Incremental peritoneal dialysis has been proved feasible and safe in asymptomatic patients with a glomerular filtration rate (GFR)<6 mL/min, but the residual renal function has to be monitored strictly. A second population is composed of asymptomatic, mostly older patients with GFR between 6 and 10 mL/min, in whom a low-dose start may preserve the residual renal function and favor a more gradual training. Lastly, patients with severe, terminal, chronic cardiomyopathy who are not candidates for a heart transplant may experience beneficial effects on cardiac function and hospitalization with low-dose peritoneal dialysis treatment even when they have GFR>10 mL/min. In conclusion, incremental peritoneal dialysis is a feasible therapeutic option that the nephrologist should know and be able to perform in those patients who may benefit from it.

Experience of 70-cm-long femoral tunnelled twin Tesio catheters for chronic haemodialysis.

BACKGROUND: Tunnelled femoral catheters with their tip in the lower inferior vena cava (IVC) are proposed only in few cases, but they often provide less than optimal blood flows and frequently have complications. The aim of this prospective observational study is to evaluate the use of 70-cm-long tunnelled cuffed femoral twin Tesio catheters with their tip in the upper IVC for haemodialysis. METHODS: Between May 2007 and May 2009, 25 tunnelled femoral catheters (fCVC) have been placed in 25 patients (77.7 +/- 10.8 years) with exhausted thoracic venous accesses or old patients with several comorbidities. Two 10 Fr carbothane 70-cm-long Tesio catheters with a Dacron cuff at 45 cm from the tip were placed in the femoral vein of each patient and then tunnelled; tips were in the upper third of the IVC. fCVCs were removed for either malfunction (Qb < 200 ml/min) or infection that did not resolve with antibiotics. RESULTS: Technical success of placement was 100%. The 6- and 12-month assisted primary patency rate were respectively 67 +/- 13% and 54 +/- 17%. The mean session Kt/V was 1.45 +/- 0.19, and the blood flow was 270 +/- 17 ml/min. Six fCVCs have been removed: three for infection, one for accidental damaging and two for the making of a different vascular access. The main complications were 2 catheter tip thrombi, 3 tunnel infections and 11 fCVC-related bacteraemia (1.77 episodes per 1000 CVC-days). CONCLUSION: The placement of twin fCVCs with their tip in the high IVC can provide an adequate dialysis and can be considered for patients with no remaining thoracic accesses.

Oxidative stress in elderly chronic renal failure patients: effects of renal replacement therapies on cell membrane fluidity.

BACKGROUND: Renal replacement therapies (RRTs) produce a partial loss of antioxidants and formation of reactive oxygen species (ROS), which are a major factor involved in alterations of plasma membrane fluidity and endothelial activation, but their role on plasma membrane fluidity in vivo is still unclear. We compared erythrocyte plasma membrane fluidity, ROS and total plasma antioxidant defenses (Lagtime) in aged patients with chronic renal failure (CRF) on conservative treatment, peritoneal dialysis (PD) and hemodialysis (HD) before (HD-pre) and after (HD-post) a treatment, to evaluate the role of different RRTs on oxidative stress and plasma membrane fluidity in aged patients. METHODS: We assessed erythrocyte plasma membrane fluidity, plasma lipid hydroperoxide levels and Lag-Time in 11 CRF patients on conservative treatment, 15 on PD, 12 on HD and 30 healthy controls. RESULTS: Hydroperoxides were higher in CRF, PD and HD-post, whereas Lag-time was significantly lower in PD, CRF and in HD-post. CRF, PD and HD-pre also had higher membrane fluidity (rsDPH), compared with HD-post and controls. CONCLUSION: These findings are in keeping with the hypothesis that the Lag-time decrease is due not only to the effect of the RRT but also to the uremic state, and that PD patients undergo a chronic, greater oxidative stress. Contrary to expectations, all patients showed greater erythrocyte membrane fluidity, which can be attributed to uremic toxicity. These observations reinforce the hypothesis that oxidative stress is an intrinsic component of this disease state and indeed is already present also in CRF not yet requiring RRT.

Home peritoneal ultrafiltration in patients with severe congestive heart failure without end-stage renal disease.

Congestive heart failure (CHF), mainly because of ischemic heart disease, is becoming a common medical problem. As CHF worsens and reaches New York Heart Association (NYHA) class IV, many patients can become refractory to medical therapy, especially those who are elderly or who have pre-existing non uremic chronic renal failure. For such patients, quality of life, morbidity, and mortality are expected to be bad. Our objective in the present study was to make a preliminary assessment of the usefulness of icodextrin administered in a single nocturnal peritoneal exchange to patients nonrespondent to the maximal conventional medical therapy. We studied two patients (aged 80 and 87 years), who were affected by severe dilatative cardiomyopathy and moderate-to-severe chronic renal failure. After at least 12 months of treatment, we observed a significant improvement in quality of life and a reduction in morbidity and hospitalization in both patients. Both patients also significantly increased their creatinine clearance. One patient maintained ejection fraction stability (22%-->27%); the other experienced an increase in ejection fraction to 50%from 25%. These preliminary observations suggest that a single nocturnal exchange with icodextrin can be an effective treatment in patients affected by refractory CHF and moderate-to-severe chronic renal failure.

Morpho-functional study of peritoneum in peritoneal dialysis patients.

BACKGROUND: Structure and function of the peritoneal membrane (PM) are impaired on peritoneal dialysis (PD). The aim of this study was to examine the relationship between dialytic parameters and histological and functional characteristics of the peritoneum of PD patients. METHODS: A peritoneal biopsy (PB) was performed on 31 PD patients during catheter removal due to malfunction or after drop-out from treatment. PB was performed at least 5 cm from the catheter insertion. For each patient PM transport was evaluated by the last peritoneal equilibration test (PET) before PB. Each daily glucose load was calculated. Tissue was formalin-embedded and stained for histological and immunohistochemical studies. RESULTS: (1) Duration of treatment was longer in patients with mesothelial impairment. (2) Patients showing sub-mesothelial sclerosis (SS) and those with impairment of submesothelial basement membrane and subendothelial vascular membrane (SVM) were submitted to a larger daily glucose load. (3) SS exceeding 50 mm was more frequent among high transporters, who were exposed to larger daily glucose load compared to medium-high transporters. (4) Mesothelial loss correlated to SS and vascular alterations. (5) SS was related to vascular injuries but not to inflammatory infiltrate. CONCLUSIONS: SS is not constant in PD patients and is not a prominent factor in treatment drop-out. Mesothelial impairment seems to be mainly related to duration of PD treatment. Glucose load seems to mainly damage the sub-mesothelial layer.