Minimally invasive peritoneal access: A new approach of catheter placement for peritoneal dialysis

BACKGROUND

Catheter implantation techniques for peritoneal dialysis (PD) have advanced significantly in recent years. We aimed to analyze the survival and associated complications of catheters inserted using a new technique that is guided by ultrasound and fluoroscopy and requires minimal tissue dissection. The procedure was performed by nephrologists in the outpatient basis, we compared these results of the minimally invasive insertion with traditional implantation using trocars.

METHODS

A total of 152 PD catheters were placed in 152 patients with stage 5 chronic kidney disease; 62.5% of the patients were men, with a mean age of 56.6 ± 18.5 years. The following two methods were used: minimally invasive insertion (MI group, n = 73) and trocar insertion (T group, n = 79). Patients in both the groups were followed prospectively for 26 months from the date of the first implantation.

RESULTS

Gender, age, and prevalence of diabetes mellitus were not significantly different between the groups, while the body mass index, presence of obesity, and abdominal scars from previous surgeries were higher in the MI group (p = 0.021). The incidence of catheter dysfunction was lower in the MI group compared to group T (6.8% vs 20.3%; p = 0.019). Exit site infection was also lower with the new technique (4.1% vs. 18.9%; p = 0.005). Further, the cumulative incidence of peritonitis also reduced with MI (p = 0.034). Finally, the overall catheter survival at 1 year was 89%, which has been shown as higher in group MI (95% vs 82% in group T; p = 0.025).

CONCLUSION

The MI technique for catheter insertion showed low complication rates and excellent catheter survival as compared to traditional implantation methods; thus, it may be an alternative method for PD catheter placement.

Health insurance provider and endovascular treatment availability are associated with different hemodialysis vascular access profiles: A Brazilian national survey

In Brazil, most hemodialysis (HD) patients are treated by the country's public health system. However, accessibility to healthcare is different for public and private patients. This study aimed to identify the profile of vascular access in a Brazilian HD sample. Additionally, it aimed to examine the influence of public and private health insurance, accessibility to endovascular treatments, and timely arteriovenous access creation on the prevalence of tunneled catheters (TCs), non-tunneled catheters (NTCs), and arteriovenous (AV) access. We conducted a cross-sectional electronic survey across 834 centers. Centers were inquired about the number of patients with public and private health insurance, the profiles of vascular access, time for AV access creation, accessibility to TC insertion and endovascular treatments, and the availability of peritoneal dialysis and kidney transplantation. Logistic regression and multilevel logistic regression were performed to evaluate possible interactions between the independent variables. A total of 7,973 patients across 47 HD centers were included in the survey. Public health patients accounted for 77% of the study sample. The overall vascular access profiles of the public and private insurance groups were significantly different (p < 0.001). For patients with public health insurance, the prevalence of any catheter was 25%, while that for private patients was 31.8% (p < 0.001). The prevalence of TCs was more common in private patients (15.3% vs. 23.1%, p < 0.001). AV accesses were more common in public health patients (75% vs. 68.2%, p < 0.001), as were fistulas (72.4% vs. 63.1%, p < 0.001). AV grafts were more prevalent among patients with private insurance (2.6 vs. 5.1%, p < 0.001). The availability of endovascular treatments increased the chance of having a TC by 2.3-fold (OR = 2.33, 95% CI = 1.30-4.18); however, it did not reduce the chance of having any catheter. A high chance of having a catheter was found when the time to AV access creation exceeded 60 days. The differences between public and private patients may be explained by underpayments and the decreased accessibility to care infrastructure in the public system, especially for endovascular treatments. In this sample, public health patients had a decreased risk of having a TC over an NTC. Differences in care accessibility and insurance type might influence the type of vascular access.

Hemodialysis Vascular access maintenance in the Covid-19 pandemic: Positioning paper from the Interventional Nephrology Committee of the Brazilian Society of Nephrology

Vascular accesses for hemodialysis are considered the patient’s lifeline and their maintenance is essential for treatment continuity. Following the example of institutions in other countries affected by the Covid-19 pandemic, the Brazilian Society of Nephrology developed these guidelines for healthcare services, elaborating on the importance of carrying out procedures for the preparation and preservation of vascular accesses. Creating definitive accesses for hemodialysis, grafts and arteriovenous fistulas are non-elective procedures, as well as the transition from the use of non-tunneled catheters to tunneled catheters, which cause less morbidity. In the case of patients with suspected or confirmed coronavirus infection, one may postpone the procedures for the quarantine period, to avoid spreading the disease.

Salvage of thrombosed arteriovenous fistulae of patients on hemodialysis: report on the experience of a Brazilian center

INTRODUCTION

Hemodialysis vascular access thrombosis is an acute event that can interrupt the dialytic treatment. A timely management can restore access patency, avoiding the use of central venous catheters and their complications.

OBJECTIVE

To present the experience from a Brazilian Interventional Nephrology Center (INC) in the salvage of arteriovenous fistula (AVF) and grafts for hemodialysis.

METHODS

A retrospective study was performed to evaluate the primary and secondary patencies of 41 hemodialysis accesses with thrombosis confirmed by ultrasound and submitted to endovascular salvage procedures. We considered clinical success the use of the access for at least 3 subsequent hemodialysis sessions. The procedures were done in an outpatient center by interventional nephrologists. Patients were followed for up to 18 months with Doppler every 3 months.

RESULTS

Forty-five salvage procedures were performed in 41 accesses of 40 hemodialysis patients with native AVF or grafts. Of these, 90% were AVF, mostly upper arm, and 10% were grafts. Clinical success rate was 60% (27 procedures). Primary patency at 12 months was 39% and secondary was 52%. Gender of the patient, diabetes, and location of the access did not correlate statistically with outcomes. There were 3 major complications (anastomosis rupture, grade 3 hematoma, and anaphylactic shock).

CONCLUSION

The majority of thrombosed accesses can be successfully treated, maintaining its long-term patency. The need of repeated intervention is frequent.

Frequency and clinical histological analysis of glomerular diseases in a tertiary hospital in southern Brazil

INTRODUCTION

The glomerulopathies are the most common biopsy-proven kidney diseases. The epidemiological investigation of glomerulopathies allows the identification of their distribution and main causes and enables the development of prevention and treatment strategies.

OBJECTIVE

This study aims to identify the frequency and clinical-pathological correlation of glomerular diseases diagnosed at the HC-UFPR over the period of 5 years.

METHODS

131 biopsies were performed between January 1, 2008 and December 31, 2012 and were analysed by light and immunofluorescence microscopy. Histopathological slides were reviewed by a pathologist. Clinical and laboratory data and the immunofluorescence microscopy results were extracted from medical records. The findings were tabulated and analysed.

RESULTS

128 of 131 cases were reanalysed. 46.5% were obtained from men. Patients' age averaged 43 years for men and 38 for women. In 99 cases, the indication of biopsy was identified; 49.5% cases presented nephrotic syndrome, 17.17%, acute renal failure and 15.15%, chronic renal failure; 8.08%, nephritic syndrome; 6.06%, isolated proteinuria and 4.04% isolated hematuria. In 61.21% an underlying disease related to the glomerulopathy could be identified; 33.62% corresponded to primary disease and in 5.17% of cases the nature of the glomerulopathy could not be determined. Among secondary glomerulopathies, the most frequent was Lupus Nephritis (49.29%), and among the primary, Focal Segmental Glomerulosclerosis (30.77%) and Membranous Nephropathy (25.64%).

CONCLUSION

The average patient with glomerulopathy in this service is an adult with nephrotic syndrome. Unlike other reports, secondary glomerulopathies were predominant. These findings may reflect the tertiary characteristic of the assistance at HC-UFPR.

Acute kidney injury in patients infected by H1N1: clinical histological correlation in a series of cases

INTRODUCTION

Influenza A (H1N1) virus was first reported on April 2009 and, since then, several studies have reported the characteristics concerning the clinical presentation and pulmonary involvement. However, accurate information about the acute kidney injury (AKI) and kidney histopathological findings in these patients remain scarce.

OBJECTIVE

To describe the kidney histopathological findings of 6 patients with H1N1 who developed AKI and underwent kidney biopsy, correlating them with clinical features.

METHODS

We studied six patients admitted to Hospital de Clínicas UFPR with a PCR-confirmed diagnosis of H1N1who developed ARF and underwent kidney biopsy. We reviewed their medical file and the microscopy findings of the biopsy.

RESULTS

Clinical and/or laboratory evidence of AKI was present in all cases, and only one did not present oliguria. Kidney tissues revealed glomerular lesions in two patients: one patient, with systemic lupus erythematosus, showed changes consistent with lupus nephritis class III A-C according to the ISN/RPS 2003 and focal thrombotic microangiopathy; the other one had intercapillary nodular glomerulosclerosis, but without clinical or laboratory evidence of diabetes. Vacuolar degenerative tubular changes were present in all cases, with focus of oxalosis in two cases. Mild to moderate atherosclerosis was found in two patients.

CONCLUSION

In this study, varying degrees of vacuolar degenerative tubular changes were present in all patients, but there were no signs of acute tubular necrosis. It seems that in the present study a prerenal cause of acute renal failure was the main involved mechanim to explain the cause of renal failure in these patients.

Minocycline-EDTA lock solution prevents catheter-related bacteremia in hemodialysis

There is growing concern about the development of antibacterial resistance with the use of antibiotics in catheter lock solutions. The use of an antibiotic that is not usually used to treat other serious infections may be an alternative that may reduce the clinical impact should resistance develop. We conducted a randomized controlled trial to compare a solution of minocycline and EDTA with the conventional unfractionated heparin for the prevention of catheter-related bacteremia in hemodialysis patients during a period of 90 d. The study included 204 incident catheters (27.8% tunneled); 14 catheters were excluded because of early dysfunction and 3 because of protocol violations. We observed catheter-related bacteremia in 19 patients in the heparin group (4.3 per 1000 catheter-days) and in 5 patients in the minocycline-EDTA group (1.1 per 1000 catheter-days; P = 0.005). We did not detect a significant difference in the rate of catheter removal for dysfunction. Catheter-related bacteremia-free survival was significantly higher in the minocycline-EDTA group than in the heparin group (P = 0.005). In conclusion, a minocycline-EDTA catheter lock solution is effective in the prevention of catheter-related bacteremia in hemodialysis patients.

Estudo citofotométrico da expressão dos marcadores tumorais Ki-67 e CD34 no adenocarcinoma de próstata

OBJETIVO: Quantificar a porcentagem da imunomarcação no índice de marcagem e densidade óptica do Ki-67 e CD34 no adenocarcinoma de próstata e compará-las entre si. MÉTODOS: Foram estudados, através de imunoistoquímica, o Ki-67 e o CD34 em 34 casos de adenocarcinoma de próstata provenientes de prostatectomia radical no período de 2000 a 2005 realizado no Hospital Regional do Gama em Brasília. Estes marcadores foram quantificados através do software SAMBA 4000 ® Sistema de Análise Microscópica de Busca Automática e do software IMMUNO® para análise das variáveis índice de marcagem e densidade óptica. Para avaliação da associação entre as expressões do marcador, foi estimado o coeficiente de correlação de Spearman. Para a comparação do tipo de lesão, foi usado o teste t de Student em amostras pareadas e não paramétrico de Wilcoxon. RESULTADOS: Dos 34 blocos que foram para leitura dos marcadores tumorais, 15 marcaram expressão com Ki-67, 34 com CD34 e 14 com ambos os marcadores. O índice de marcagem do CD34 teve valor mediano de 72,72%, valor mínimo 5,14% e valor máximo 88,81%. O índice de marcagem do Ki-67 teve mediana de 73,78%, mínimo de 16,87% e máximo de 87,47%. A densidade óptica do CD34 teve mediana de 48,33, mínimo de 35,65 e máximo de 85,86. Na densidade óptica do Ki-67 o valor da mediana foi 40,03 sendo a mínima de 21,53 e a máxima de 52,43. CONCLUSÃO: A expressão citofotométrica do Ki-67 teve índice médio de marcação de 64,04% e o CD34 de 61,64%. A expressão citofotométrica da densidade óptica média do Ki-67 foi de 39,49 e no CD34 de 53,69. Há diferença significativa entre a imunomarcação do Ki-67 e CD34 em relação à densidade óptica (p=0,025), não havendo diferença significativa no índice de marcagem (p=0,470).

Complications of the peritoneal access and their management

Although peritoneal catheter insertion is relatively considered a minimal invasive procedure, it is associated with some complications. These complications are divided into mechanical (bleeding, visceral perforation, dialysate leaks, catheter dysfunction, hernia formation, cuff extrusion) and infectious (early peritonitis, surgical wound, tunnel and exit site infections). It is well recognized that the appearance of these complications can increase morbidity and the chance of peritoneal dialysis treatment failure. Independent of the insertion technique, the operator must be prepared to an immediate recognition and adequate management of complications. Pre-operative evaluation and identification of potential risk factors are essential to prevent them.

Accuracy of physical examination and intra-access pressure in the detection of stenosis in hemodialysis arteriovenous fistula

Both physical examination (PE) and intra-access pressure (IAP) measurements have been used in the identification of stenosis in an arteriovenous access. The aim of this study was to evaluate the accuracy of PE and IAP in the diagnosis of arteriovenous fistula (AVF) stenosis. A total of 84 patients were enrolled in the study (54% men, mean age of 50.7 +/- 12.7 years and mean AVF patency of 24.9 +/- 7.8 months, 52% radiocephalic). Abnormalities of pulse and thrill were used as the diagnostic tools for the detection of stenosis using the physical examination. For IAP, stenosis was suspected when the ratio between IAP at the arterial puncture site and the mean blood pressure was <0.13 or >0.43. The diagnosis of stenosis was confirmed by Doppler ultrasound (DU). Sensitivity (S), specificity (SP), positive predictive value (PPV), negative predictive value (PNV), and accuracy were calculated for the two early detection tests. According to DU, 50 (59%) AVF were considered positive for the presence of stenosis. Fifty-six (66%) AVF were considered positive for the presence of stenosis by PE and 34 (40%) by IAP. S, SP, PPV, and NPV for PE and IAP were 96%, 76%, 86%, and 93% and 60%, 88%, 88%, and 60%, respectively. The accuracy for PE and IAP was 88% and 71%, respectively. PE proved to be an accurate method for the diagnosis of stenosis and should be part of all surveillance protocols of stenosis detection in AVF.