The intraoperative intravascular lithotripsy to recruit a calcified radial artery for creating a distal radio-cephalic fistula.

Guidelines for vascular access recommend that the distal autogenous arteriovenous fistula (AVF) should be the first choice-access procedure for patients starting dialysis. Arteriosclerosis of radial artery may cause early failure, as well as failure of maturation of distal arteriovenous fistulas. To increase the incidence of distal AVFs, our team, specialized in vascular access surgery from 2004 onwards, has introduced Intraoperative Transluminal Angioplasty (ITA) under ultrasound (UG) or fluoroscopic guidance, to recruit inadequate arterials for creating distal fistulas. Intravascular lithotripsy (IL) is a novel approach to treat luminal and medial calcifications in patients with peripheral arterial disease and coronary disease. We believe that intraoperative IL may be an opportunity to recruit calcified radial arteries for creating distal radio-cephalic fistulas. Purpose of this study is to describe the intraoperative IL technical applied in our clinical experience. A 37-year-old diabetic patient with distal radio-cephalic fistula was recruited for the first IL experience. One year ago, a wrist radio-cephalic fistula was created in the right upper limb, with intraoperative UG radial artery angioplasty for extensive calcifications. The fistula was functioning but showed a delay in maturation. An angioplasty was unsuccessfully attempted to facilitate the maturation. Subsequently, a surgical revision of the fistula was performed, creating a new anastomosis immediately upstream of the previous one by performing an intraoperative IL UG of the radial artery. The fistula was immediately well functioning, and was cannulated with two needles after 1 month. It is currently being used with intradialytic adequate blood flow. The positive outcome of the case described in this paper, even if only anecdotal, could act as a trigger for further experiences with IL.

The Pre-dilatation of vessels: A simple method to recruit small caliber veins for creating distal fistulas.

Maturation failure remains a major clinical problem of distal arteriovenous fistula (AVF). Early failure (EF) is associated with the small size of the veins. For about 10 years we have used in more than 1000 fistulas, the Vessels Pre-Dilatation (VPD) to increase the recruitment of small veins for creating distal AVFs. The purpose of this study is to highlight if the VPD can reduce the incidence of EF or failure to mature (FTM) in AVFs created with small veins. Data of all the consecutive patients directly admitted to our Department for their first distal AVF from January to December 2019 were collected. The patients were divided in two groups, one with a vein diameter after the tourniquet ⩽2.0 mm (G1) and one >2 mm (G2). Both in G1 then in G2 the vessels had undergone VPD. Immediate failure (IF), EF, FTM, delayed or arrested maturation rate (DAM), unassisted AVFs and matured AFVs were evaluated. The patients recruited totalled 104, 37 in G1, and 67 in G2. The two groups were homogeneous in age, incidence of diabetes, obesity, heart disease, peripheral vasculopathy, and race. Female were more numerous in G1 (51% vs 12%, p < 0.001). In G1 and G2 occurred respectively 3 IF versus zero (p < 0.05), 10 EF (29%) versus 6 (9%) (p < 0.05), 6 DAM (16%) versus 6 (9%), 21 unassisted AVFs (57%) versus 57 (85%) (p < 0.01). Dividing the patients into groups of unassisted and assisted AVFs, female and low vein diameter are more represented in the assisted group. There were 32 matured AVFs (86%) in G1 and 65 (97%) in G2. In order to increase the incidence of the distal AVF, the PDV allows to include small veins. However, more patients require further interventions to achieve maturation of the fistula.

[Nutritional therapy in chronic proteinuric nephropathy].

Proteinuria is a well-known marker of renal damage and, at the same time, an important factor in the progression of chronic kidney disease itself. The scientific community has always sought to investigate and provide answers on how nutritional therapy can influence and modify proteinuria and therefore limit its impact on progression to end-stage renal disease. However, despite the importance of the topic, the studies rarely take the form of randomized and controlled trials; in any case, they are often limited to protein intake only, conducted on very heterogeneous populations and, finally, they rarely indicate the precise values of proteinuria. The aim of this work is to explore the different nutritional approaches and their implications in the pathological conditions associated with proteinuria.

How to create and preserve distal fistulas in a large number of patients: the experience of a single centre.

Background: Distal arterio-venous fistula (AVF) is considered the gold standard for vascular access in hemodialysis. The aim of this retrospective study is to report our experience on two innovative techniques, Intraoperative Transluminal Angioplasty (ITA) and Vessel Pre-Dilatation (VPD). Methods: We collected data from all the consecutive patients directly admitted to our Department from January 2014 to October 2018 in order to create or repair an AVF. Early Failure (EF), Failure to Mature (FTM), Late Failure (LF), Primary and Secondary patency rate were evaluated. Results: All patients underwent VPD; of the total 647 AFVs, 128 received an ITA for the presence of suboptimal vessels. 98.3% of AVFs were located on the forearm. EF occurred in 83 cases; in 67 of these a new AVF was successfully created upstream from the previous one. LF occurred in 100 cases; of these, the access was abandoned in 32 cases and we performed a new AVF upstream from the previous one in 68 cases. FTM occurred in 57 cases, 31 of which were treated with Percutaneous Transluminal Angioplasty (PTA) whilst 26 were resolved performing a new anastomosis upstream. Primary and secondary patency at 1, 2, 3 and 4 years were, respectively, 80%, 74%, 68%, 64% and 94%, 91%, 89%, 88%. By dividing patients into an ITA group and a control group, we did not find any difference in primary and secondary patency. Conclusions: VPD and ITA could be useful to increase the incidence and the prevalence of distal AVF.

[Prototyping a new registry of vascular accesses for hemodialysis].

We have developed a new registry of the Vascular Accesses (VA) of all the patients afferent to our health district in order to improve their management. We recorded all the VAs of the prevalent patients on 12/31/2017. The VA type and location, the vessels involved, the number of surgical procedures received by the patient and the kind of anastomosis of the VA were all recorded. As for Central Venous Catheters (CVC), we recorded the reason for the choice as well as the site and the characteristics of CVC. Results: The VA of 726 prevalent patients were registered. Their age was 66+15 years on average, and 63% were male. The native arteriovenous fistulas (AVF) were 609 (84%), of which 65% were located on the distal forearm (DF), 10% on the middle forearm (MF), 5% on proximal forearm (PF), 4% on the arm (AM). The arteriovenous Grafts (AVG) were 12 (1.7%). The CVCs were 105 (14.5%). More women than men received a CVC (p<0.005) or an AVF on the AM (p<0.05). Patients over 75 had less FAVs in the AM (P<0.05) and less Grafts (P<0.05). Diabetics patients had more CVCs (p<0.05) but were generally older (p<0.001). Patients in HD for renal transplantation loss had more AVFs at the arm (p<0.001) and Grafts (p<0.001), and less AVFs on the DF (p>0.001). The comparison of data between 2013 and 2017 shows a steady situation in the prevalence of VA. Conclusions: The new VA registry has allowed us to detect and record important information, both from a clinical and an epidemiological point of view.

[The treatment of AKI in nephrology hospitalization: the SLE-HDF 15 litres in 10 hours].

The AKI in intensive care has been widely treated by international and national guidelines. The treatment of AKI in patients not requiring admission in Intensive Care Unit, but often hospitalized in Nephrology Unit, it is showed of less relevance. For over 5 years we have used for the treatment of AKI of patients admitted in Nephrology Unit an intermittent slow technique, implemented in approximately 600 patients with AKI for a total of about 3000 treatments. In this study we report the clinical results obtained in 100 consecutive patients referred to our Nephrology Unit from 1st January 2014. We excluded the patients with AKI and lactic acidosis by metformin, which were treated with CVVHDF. The Dialysis Protocol provides a slow low efficiency intermittent treatment called SLE-HDF (Sustained Low Efficiency Hemo-Dia-Filtration), with 10-hour duration, 1.5 L/h dialysate for a patient up to 75 kg, 2 L/h up to 85 kg, 2.5 L/h over 85 kg. Half of the dialysate was used in convention in post and half in diffusion. Endpoints were the recovery of renal function and the survival of the patient. On each patient was calculated on at least one seat, the Kt/V urea (UKt/V). Were studied 100 patients, 45 females and 55 males, with mean age 79.4 + 11 years. The weight was 74 kg + 18 kg at the start of treatment. The 65% of patients had diuresis < to 500 ml/24 hours. The causes of AKI were: 41% heart failure, 31 % AKI on MRC, 7% rhabdomyolysis, 6% Hepato-renal Syndrome, 4% sepsis, 11 % other causes. Major comorbidities were heart disease (63%), diabetes (50%), COPD (38%), age over 85 years, cancers 23, liver disease 16, hypotension requiring amine 15, sepsis 10. In total in the 100 patients, 512 treatments were performed, average 5.12 + 3.7. The mean UKt/V was 0.4 + 0.05 per session. The deaths were 43. Patients discharged were 57. Of these, 43 had a recovery of renal function. Fourteen patients have not recovered renal function and were admitted for chronic dialysis treatment. In conclusion, our protocol of SLE-HDF, which uses volumes of dialysate sharply lower than used in literature, has been shown to be effective in correcting the biochemical profile of the patient with AKI. The clinical results are considered satisfactory, having obtained the improvement in 57% of patients, considering that the 43 deaths, 10 were suffering from Hepato-cirrhosis and 13 from malignant neoplasm. Further studies are needed to confirm our findings.

[Adrenal pheochromocytoma associated with "tako-tsubo" syndrome]. / Un caso di feocromocitoma surrenalico manifestatosi con un quadro di cardiomiopatia tipo "tako-tsubo".

"Tako-tsubo" cardiomyopathy is a condition characterized by a transitory left ventricular asinergia, induced by physical and emotional stress. In literature there are few cases of association between cardiomyopathy and pheochromocytoma. We described a case of a 72 year-old woman admitted in Emergency Room for chest pain associated with high blood pressure: the ECG showed non-ST elevation in leads III, AVF and V1. An echocardiogram showed global reduction in contractility (EF 40%) with apical akinesia. The coronary angiography showed coronary without stenosis while left ventriculography showed an average apical akinesia of the anterior wall with enhanced contractility of basal segments. Subsequently, the patient continued to present episodes of tremors associated with high blood pressure and therefore was made the determination of urinary metanephrines and urinary vanilmandelic acid that were both high. A subsequent abdomen MRI showed a 32 mm left adrenal lesion with arterial phase impregnation. The diagnosis of left adrenal pheochromocytoma was made and the tumor, after appropriate preoperative pharmacological preparation with α-blockers, was removed surgically. In conclusion, the unexplained transitory left ventricular asinergia alert the clinician of an underlying disorder, such as pheochromocytoma, the early detection of which is crucial to the prognosis.