Lung ultrasound findings in pediatric community-acquired pneumonia requiring surgical procedures: a two-center prospective study.

BACKGROUND: Lung ultrasound (US) in the evaluation of suspected pediatric pneumonia is increasingly used and has a recognized role in evaluating pleural effusions, although there are no detailed studies specifically addressing its use in the pediatric population. OBJECTIVES: To define lung US findings of severe pediatric community-acquired pneumonia that required surgical procedures during admission. MATERIALS AND METHODS: Our prospective case-control study compared lung US findings in patients ages 1 month to 17 years admitted with community-acquired pneumonia that required surgical procedures from findings those who did not. Lung US was performed at admission and always before surgical procedures. Medical treatment, laboratory and microbiological findings, chest X-ray, computed tomography scan and surgical procedures are described. RESULTS: One hundred twenty-one children with community-acquired pneumonia were included; of these, 23 underwent surgical intervention. Compared with the control group, children requiring a surgical procedure had a significantly higher rate of large consolidations (52.2%; 95% confidence interval [CI]: 30.6% to 73.2%), larger and complicated pleural effusions (100%; 95% CI: 85.2% to 100%), and both liquid and air bronchograms (73.9%; 95% CI: 51.6% to 89.8%). CONCLUSION: Larger consolidations, larger and more complicated pleural effusions, and liquid and air bronchograms were associated with surgical treatment.

The first five years of neonatal and pediatric transports on extracorporeal membrane oxygenation in the center and south of Italy: The pediatric branch of the Italian "Rete Respira" network.

INTRODUCTION: Neonatal and pediatric ECMO is a high-risk procedure that should be performed only in expert centers. Children who are eligible for ECMO and are managed in hospitals without ECMO capabilities should be referred to the closest ECMO center before the severity of illness precludes safe conventional transport. When the clinical situation precludes safe conventional transport, ECMO should be provided on site with the patient transported on ECMO. METHODS: We retrospectively reviewed our institutional database of all ECMO transports for neonatal and pediatric respiratory failure from February 2013 to February 2018. RESULTS: Over the last 5 years, we provided 24 transports covering all requests from the center and south of Italy except for the islands. Of these transports, 20 were performed on ECMO and 4 without ECMO. No patient died during transportation. Five complications were reported only during the ECMO transports, and all of these were managed without compromising the patient's safety. The preferred modes of transport were by ambulance (70%) and ambulance transported into the fixed wing aircraft (30%) for longer national distances. The survival to hospital discharge of the patients transported with ECMO was 75% among the neonatal transports and 83.3% among the pediatric transports. The survival to hospital discharge of the four patients transported without ECMO was 100% for both neonates and children. CONCLUSIONS: Neonatal and pediatric ECMO transports can be safely performed with a dedicated team that maintains stringent adherence to well-designed management protocols.

Nationwide study of headache pain in Italy shows that pain assessment is still inadequate in paediatric emergency care.

AIM: Italian national guidelines on pain management were published in 2010, but there is little information on how effective pain management is in paediatric emergency care, with other countries reporting poor levels. Using headache as an indicator, we described pain assessment in Italian emergency departments and identified predictors of algometric scale use. METHODS: All Italian paediatric and maternal and child hospitals participated, plus four general hospitals. Data on all children aged 4-14 years admitted during a one-month period with headache as their chief complaint were abstracted from clinical records. Multivariable analyses identified predictors of algometric assessment, taking into account the cluster study design. RESULTS: We studied 470 admissions. During triage, pain was assessed using a standardised scale (41.5%), informally (15.5%) or was not recorded (42.9%). Only 32.1% of the children received analgesia in the emergency department. The odds ratios for predictors of algometric assessment were non-Italian nationality (3.6), prehospital medication (1.8), admission to a research hospital (7.3) and a more favourable nurses-to-admissions ratio of 10.8 for the highest versus lowest tertile. CONCLUSION: Despite national guidelines, paediatric pain assessment in Italian emergency care was suboptimal. Hospital variables appeared to be stronger predictors of adequate assessment than patient characteristics.

Evolution of Noninvasive Mechanical Ventilation Use: A Cohort Study Among Italian PICUs.

OBJECTIVE: To assess how clinical practice of noninvasive ventilation has evolved in the Italian PICUs. DESIGN: National, multicentre, retrospective, observational cohort. SETTING: Thirteen Italian medical/surgical PICUs that participated in the Italian PICU Network. PATIENTS: Seven thousand one-hundred eleven admissions of children with 0-16 years old admitted from January 1, 2011, to December 31, 2012. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Cause of respiratory failure, length and mode of noninvasive ventilation, type of interfaces, incidence of treatment failure, and outcome were recorded. Data were compared with an historical cohort of children enrolled along 6 months from November 1, 2006, to April 30, 2007, over the viral respiratory season. Seven thousand one-hundred eleven PICU admissions were analyzed, and an overall noninvasive ventilation use of 8.8% (n = 630) was observed. Among children who were admitted in the PICU without mechanical ventilation (n = 3,819), noninvasive ventilation was used in 585 patients (15.3%) with a significant increment among the three study years (from 11.6% in 2006 to 18.2% in 2012). In the endotracheally intubated group, 17.2% children received noninvasive ventilation at the end of the weaning process to avoid reintubation: 11.9% in 2006, 15.3% in 2011, and 21.6% in 2012. Noninvasive ventilation failure rate raised from 10% in 2006 to 16.1% in 2012. CONCLUSIONS: Noninvasive ventilation is increasingly and successfully used as first respiratory approach in several, but not all, Italian PICUs. The current study shows that noninvasive ventilation represents a feasible and safe technique of ventilatory assistance for the treatment of mild acute respiratory failure. Noninvasive ventilation was used as primary mode of ventilation in children with low respiratory tract infection (mainly in bronchiolitis and pneumonia), in acute on chronic respiratory failure or to prevent reintubation.

Adoptive immunotherapy with antigen-specific T cells during extracorporeal membrane oxygenation (ECMO) for adenovirus-related respiratory failure in a child given haploidentical stem cell transplantation.

We report on the successful infusion of human adenovirus (HAdV)-specific T cells in a child with congenital amegakaryocytic thrombocytopenia, given T-cell-depleted hematopoietic stem cell transplantation (HSCT) from the HLA-haploidentical mother during extracorporeal membrane oxygenation (ECMO) for severe HAdV-related respiratory failure. Donor-derived, interferon (IFN)-γ-secreting HAdV-specific T cells were enriched using the cytokine capture assay, after in vitro stimulation with overlapping peptides from the immunodominant HAdV5 hexon protein. Two weeks after T-cell transfer, viral load decreased and ECMO was discontinued. T-cell responses to HAdV antigens were documented after four weeks and were associated with viral clearance, immune reconstitution and clinical amelioration.

Transient cardiac effects in a child with acute cholinergic syndrome due to rivastigmine poisoning.

BACKGROUND: We report a case of rivastigmine poisoning resulting in a full cholinergic syndrome with nicotinic, muscarinic, and central effects requiring supportive or intensive care in a pediatric patient. CASE REPORT: A 3-year-old girl was admitted to the Emergency Department suspected of having ingested one or two pills of rivastigmine. The child was hyporeactive, with symptoms of altered mental status, sialorrhea, sweating, and diarrhea. Subsequently, she started showing signs of respiratory failure, severe tracheobronchial involvement, and gastric and abdominal distension. An electrocardiogram recorded frequent monomorphic ventricular ectopic beats with bigeminy and trigeminy. Long-term follow-up showed a transient dysrhythmia. CONCLUSION: Poisoning with rivastigmine can be a life-threatening condition. Timely identification and appropriate management of the toxic effects of this drug are essential and often life-saving. This is particularly true in cases of cholinergic syndrome subsequent to drug poisoning. Patients with cholinergic syndrome should also be assessed for possible cardiac complications such as dysrhythmias. The main factors predisposing to the development of such complications are autonomic disorder, hypoxemia, acidosis, and electrolyte imbalance.

Nephrology Partnership for Advancing Technology in Healthcare (N-PATH) Erasmus+ project: The Renal Expert in Vascular Access (REVAC) module.

The Renal Expert in Vascular Access (REVAC) is one of the four modules of the Nephrology Partnership for Advancing Technology in Healthcare (N-PATH) project, the first European-wide advanced training course in diagnostics and interventional nephrology, funded by Erasmus+ Knowledge Alliance, a European Commission program. The N-PATH primary goal was to train 40 young European nephrologists in both theoretical knowledge and practical skills related to interventional nephrology. The REVAC module focused on the crucial aspects of vascular access (VA) care in nephrology practice, as a complementary training path to the actual residency program. The aim was to provide nephrology fellows with comprehensive knowledge and skills related to VA management. The methodology was based on face-to-face meetings and online learning, modern facilities, experienced tutors, cutting edge simulators, augmented reality tools by means of a multidisciplinary international faculty and hands-on-courses. A feedback survey reported the experience of fellows who attended the REVAC module, confirming the positive impact on their ongoing nephrology training. We are confident that this project will revitalize their nephrology careers and will help training the next generation of nephrologists; they will be able to manage VA needs with the help of multi-disciplinary teams to safely optimize the care of hemodialysis patients.

Vascular access for hemodialysis in Italy: What a national survey reveals.

BACKGROUND: Since in Italy there are no official data on vascular access (VA) for hemodialysis the Vascular Access Project Group (VAPG) of the Italian Society of Nephrology (SIN) designed a national survey. METHODS: A 35-question survey was designed and sent it to the Italian facilities through the SIN website. The basic questions were the prevalence, the location, and the surveillance of VA, the bedside use of ultrasound, the use of fluoroscopy for central venous catheter (CVC) placement, and of buttonhole technique, the role of nephrologist in the access creation. RESULT: The questionnaire was completed in June 2022 by 161 facilities. The survey registered 15,499 patients, approximately one-third of the Italian dialysis population. The prevalence of arteriovenous fistula (AVF), arteriovenous Graft (AVG), and CVC were 61.8%, 3.7%, and 34.5% respectively. The AVF location was 50% in distal forearm, 20% in meanproximal forearm, 30% in upper arm. For AVF creation, nephrologists were involved in 72% of facilities while for CVC placement in 62%. As regards VA monitoring, 21% of the facilities did not have a surveillance protocol; 60% did not register AVF thrombosis and 53% did not register CVC infections. Most of facilities use the fluoroscope during CVC placement, 37% when needed, and 22% never. Ultrasound-guided puncture of complex AVFs was used by 80% of facilities. Buttonhole puncture was used in 5% of patients. CONCLUSIONS: Some considerations emerge from the survey data: (1) The increasing CVC prevalence compared to DOPPS 5 study. (2) The low rate of AVG prevalence. (3) The nephrologist is the operator in many VA procedures. (4) The fluoroscopy for CVC placement and the US-guide puncture of the complex AVF are widely used in most facilities. (5) The practice of the buttonhole is not widespread. (6) When the operator is the nephrologist more distal fistulas are performed.

Pain management policies and practices in pediatric emergency care: a nationwide survey of Italian hospitals.

BACKGROUND: Pain experienced by children in emergency departments (EDs) is often poorly assessed and treated. Although local protocols and strategies are important to ensure appropriate staff behaviours, few studies have focussed on pain management policies at hospital or department level. This study aimed at describing the policies and reported practices of pain assessment and treatment in a national sample of Italian pediatric EDs, and identifying the assocoated structural and organisational factors. METHODS: A structured questionnaire was mailed to all the 14 Italian pediatric and maternal and child hospitals and to 5 general hospitals with separate pediatric emergency room. There were no refusals. Information collected included the frequency and mode of pain assessment, presence of written pain management protocols, use of local anaesthetic (EMLA cream) before venipuncture, and role of parents. General data on the hospital and ED were also recorded. Multiple Correspondence Analysis was used to explore the multivariable associations between the characteristics of hospitals and EDs and their pain management policies and practices. RESULTS: Routine pain assessment both at triage and in the emergency room was carried out only by 26% of surveyed EDs. About one third did not use algometric scales, and almost half (47.4%) did not have local protocols for pain treatment. Only 3 routinely reassessed pain after treatment, and only 2 used EMLA. All EDs allowed parents' presence and most (17, 89.9%) allowed them to stay when painful procedures were carried out. Eleven hospitals (57.9%) allowed parents to hold their child during blood sampling. Pediatric and maternal and child hospitals, those located in the North of Italy, equipped with medico-surgical-traumatological ED and short stay observation, and providing full assessment triage over 24 hours were more likely to report appropriate policies for pain management both at triage and in ER. A nurses to admissions ratio ≥ median was associated with better pain management at triage. CONCLUSIONS: Despite availability of national and international guidelines, pediatric pain management is still sub-optimal in Italian emergency departments. Multifaceted strategies including development of local policies, staff educational programs, and parental involvement in pain assessment should be carried out and periodically reinforced.

Performance of the pediatric index of mortality 2 (PIM-2) in cardiac and mixed intensive care units in a tertiary children's referral hospital in Italy.

BACKGROUND: Mortality rate of patients admitted to Intensive Care Units is a widely adopted outcome indicator. Because of large case-mix variability, comparisons of mortality rates must be adjusted for the severity of patient illness at admission. The Pediatric Index of Mortality 2 (PIM-2) has been widely adopted as a tool for adjusting mortality rate by patients' case mix. The objective of this study was to assess the performance of PIM-2 in children admitted to intensive care units after cardiac surgery, other surgery, or for other reasons. METHODS: This was a prospective cohort study, conducted in a 607 inpatient-bed tertiary-care pediatric hospital in Italy, with three pediatric intensive care Units (PICUs) and one cardiac Unit (CICU). In 2009-11, all consecutive admissions to PICUs/CICU of children aged 0-16 years were included in the study. Discrimination and calibration measures were computed to assess PIM-2 performance. Multivariable logistic regression analysis was used to assess the association of patients' main reason for intensive care admission (cardiac-surgical, other-surgical, medical), age, Unit and year with observed mortality, adjusting for PIM-2 score. RESULTS: PIM-2 data collection was completed for 91.2% of total PICUs/CICU patient admissions (2912), and for 94.8% of patients who died in PICUs/CICU (129). Overall observed mortality was 4.4% (95% CI, 3.7-5.2), compared to 6.4% (95% CI, 5.5-7.3) expected mortality. Standardised mortality ratio was 0.7 (95% CI: 0.6-0.8). PIM-2 discrimination was fair (area under the curve, 0.79; 95% CI: 0.75-0.83). Calibration was less satisfactory, mainly because of the over two-fold overprediction of deaths in the highest risk group (114.7 vs 53; p < 0.001), and particularly in cardiac-surgical patients. Multivariable logistic analysis showed that risk of death was significantly reduced in cardiac-surgical patients and in those aged 1 month to 12 years, independently from PIM-2. CONCLUSIONS: The children age distribution and the proportion of cardiac-surgical patients should be taken into account when interpreting SMRs estimated using the PIM-2 prediction model in different Units. A new calibration study of PIM-2 score might be needed, and more appropriate cardiac-focused risk-adjustment models should be developed. The role of age on risk of death needs to be further explored.

[Hyponatremia and syndrome of inappropriate ADH secretion (SIADH)]. / Iponatriemia e sindrome da inappropriata secrezione di ormone antidiuretico (SIADH).

The syndrome of inappropriate ADH secretion (SIADH), also termed ''syndrome of inappropriate antidiuresis (SIAD)'', is an often unrecognized cause of hypotonic hyponatremia, arising from ectopic release of ADH in lung cancer or as a side effect of various drugs. In SIADH, hyponatremia results from selectively impaired water excretion by the kidney, whereas the external Na+ balance is normally regulated. Despite the increase in total body water, only a slight reduction of urine output and modest edema are usually seen. Renal function and acid-base balance are generally preserved, while subclinical neurological impairment may occasionally become life-threatening, when hyponatremia has an abrupt onset. The major clinical variants of SIADH are reviewed here, with particular emphasis on causes, iatrogenic complications and hospital-acquired hyponatremia. Effective treatment of SIADH is based on water restriction, hypertonic saline plus loop diuretics, or aquaretics. Worsening of hyponatremia may result from parenteral isotonic fluid administration, emphasizing the importance of an early diagnosis and careful follow-up of these patients.

Double guidewire technique (DGT): Optimising endovascular revision of juxta-anastomotic stenosis in AV-fistulae: A retrospective analysis.

BACKGROUND: Arteriovenous fistula (AVF) is the preferred angioaccess for haemodialysis but suffers from a high stenosis rate, juxta-anastomotic stenosis (JAS) being the most frequent. Percutaneous transluminal angioplasty (PTA) of JAS would have some advantage (such as mini-invasive and vein sparing treatment), but higher recurrence rate is observed as compared to surgery. We report results of juxta anastomotic stenosis PTA using the 'double guide technique' (DGT) as described by Turmel-Rodrigues, in a selected cohort from our Vascular Access Centre. PATIENTS AND METHODS: From January to June 2018, 25 consecutive patients were treated by DGT. By means of retrograde access through the outflow vein by a 6 F introducer, two guide wires were navigated: one into proximal radial artery (GW1), the other into distal artery (GW2). GW2 was used to dilate juxta-anastomotic vein and anastomotic area with 6 mm high-pressure balloon, while by GW1 juxta-anastomotic artery was dilated with 4 mm semi-compliant balloon. Mean diameter of balloons were 6.7 and 4.1 mm for venous and arterial tract dilatation. Follow up was carried out up to 12 months. Prospectively collected data were analysed retrospectively. RESULTS: One-year primary and secondary patency was 52% and 95% respectively. Recurrence rate was 0.56 procedure/pt/year. Mean access blood flow at 12 months was 830 ml/min. CONCLUSION: Double Guidewire Technique is an effective and minimally invasive procedure. By avoiding under dilation of JAS the recurrence rate resulted quite satisfactorily in our population.

[Hypertensive crisis in kidney patients]. / Le crisi ipertensive nel paziente nefropatico.

The classification and management of hypertensive crisis have been recently reviewed in the context of both European and American guidelines. The key points for proper blood pressure control in severe arterial hypertension are: 1 - Distinction between urgent intervention and emergencies 2 - Choice of the best drug(s) 3 - Choice of the correct route of administration. In patients with renal disease, beside the common causes of hypertension/ hypertensive crises, kidney-specific causes should be taken into account such as renal parenchymal hypertension, renovascular hypertension, sclerodermic crises, and preeclampsia.

Monitoring the Patient Following Radio-Cephalic Arteriovenous Fistula Creation: Current Perspectives.

Autogenous radial-cephalic direct wrist arteriovenous fistula (RC-AVF) in the non-dominant arm is the gold standard for dialysis vascular access. However, the RC-AVF non-maturation rate is significant (≃ 40%) due to an increasingly elderly and comorbid population incidence. A detailed identification of the biological cascade underlying arteriovenous fistula (AVF) maturation could be the key to clinical research aimed at identify the group of patients at risk of primary AVF failure. Currently, careful post-operative monitoring remains the most crucial aspect to overcome the problem of impaired maturation. Up to 80% of patients with immature RC-AVF have problems potentially solvable with early endovascular or surgical correction. Physical examination by experienced practitioners in conjunction with duplex ultrasound examination (DUS) can identify physical signs of non-maturation, understand the underlying cause, and drive for a tailored early planning to treat the complication. New approaches for the early assessment of AVF maturation are under study. Techniques to promote RC-AVF maturation performed through the administration of pre-or peri-operative drugs have missed up to now to prove an efficacy in improving fistula success. The new techniques tested after surgery appear to hold future promise for improving fistula maturation.

Health Technology Assessment of Intensive Care Ventilators for Pediatric Patients.

This paper is aimed at addressing all the critical aspects linked to the implementation of intensive care ventilators in a pediatric setting, highlighting the most relevant technical features and describing the methodology to conduct health technology assessment (HTA) for supporting the decision-making process. Four ventilator models were included in the assessment process. A decision-making support tool (DoHTA method) was applied. Twenty-eight Key Performance Indicators (KPIs) were identified, defining the safety, clinical effectiveness, organizational, technical, and economic aspects. The Performance scores of each ventilator have been measured with respect to KPIs integrated with the total cost of ownership analysis, leading to a final rank of the four possible technological solutions. The final technologies' performance scores reflected a deliver valued, contextualized, and shared outputs, detecting the most performant technological solution for the specific hospital context. HTA results had informed and supported the pediatric hospital decision-making process. This study, critically identifying the pros and cons of innovative features of ventilators and the evaluation criteria and aspects to be taken into account during HTA, can be considered as a valuable proof of evidence as well as a reliable and transferable method for conducting decision-making processes in a hospital context.

Potassium channels: the 'master switch' of renal fibrosis?

Progressive renal fibrosis resulting from proliferation of interstitial fibroblasts is a hallmark of chronic kidney failure, whatever the origin. The intermediate/small-conductance Ca(2+)-activated K(+) channel (K(Ca)3.1) promotes mitogenesis in several cell types by altering the membrane potential, thus enabling extracellular Ca(2+) entry. Grgic et al. evaluated the role of K(Ca)3.1 in renal fibroblast proliferation, testing whether deficiency or pharmacological blockade of K(Ca)3.1 suppressed development of renal fibrosis. Mitogens stimulated K(Ca)3.1 in murine renal fibroblasts via a MEK-dependent mechanism, while selective blockade of K(Ca)3.1 inhibited fibroblast proliferation by promoting G0/G1 arrest. In a classical model of renal fibrosis, mouse unilateral ureteral obstruction (UUO), robust up-regulation of K(Ca)3.1 was detectable in affected kidneys. K(Ca)3.1 KO mice showed reduced expression of fibrotic marker expression, less chronic tubulointerstitial damage, collagen deposition and alpha-smooth muscle+ cells after UUO, with better preservation of functional renal parenchyma. The selective K(Ca)3.1 blocker TRAM-34 similarly attenuated progression of UUO-induced renal fibrosis in wild-type mice and rats. Thus, Grgic et al. believe that K(Ca)3.1 is involved in renal fibroblast proliferation and fibrogenesis, suggesting that K(Ca)3.1 may serve as a therapeutic target for the prevention of fibrotic kidney disease.

Microsurgery and preventive haemostasis for autogenous radial-cephalic direct wrist access in adult patients with radial artery internal diameter below 1.6 mm.

BACKGROUND: Autogenous radial-cephalic direct wrist arteriovenous fistula (RCF), the gold standard for chronic dialysis, suffers from an elevated early failure rate (up to 20-50% with a pooled rate of 15.3%). Guidelines indicate that a small radial artery internal diameter (<1.6-2 mm) is strongly predictive of this early failure. Microsurgery and preventive haemostasis have been reported to give excellent results in a paediatric population (children <10 kg bw) and have shown a much lower early failure rate of 5-10%. Given these excellent results, we have used microsurgery along with preventive haemostasis in adult patients. We herein describe the results of RCF created in patients with a radial artery internal diameter <1.6 mm. METHODS: From November 2004 to December 2007, 28 RCFs were created in 28 patients with a distal radial artery internal diameter <1.6 mm using microsurgery and preventive haemostasis. The median age was 68 and the male/female ratio was 6/22. The incidence of age >65 years was 64%, hypertension 96%, diabetes 32.1%, obesity (BMI>30) 35%, vascular disease 46%. The mean distal radial artery and cephalic vein internal diameters, measured with ultrasound examination, were 1.3 mm and 1.9 mm, respectively. Seventy-five percent of the patients were not yet on dialysis treatment; 19% of whom had a previous failed vascular access created elsewhere without microsurgery. The remaining 25% patients were on dialysis treatment with a temporary femoral catheter. RESULTS: All interventions ended with a patent anastomosis; no thrombosis occurred within the initial 24 h. The early failure rate was 14% (4 out of 28 patients). The causes of early failure were thrombosis >1 week after surgery in one patient, lack of maturation (patent but unfunctional fistula) due to juxta-anastomotic vein stenosis in two patients and mid-vein stenosis in one patient. Treatment for all patients was proximalization of the anastomosis at the distal/mid forearm. Primary patency and secondary patency at 1 year were 68 +/- 10% and 96 +/- 5%, respectively. CONCLUSIONS: From our findings, we have shown that it is possible to create RCF in adult patients with a radial artery internal diameter of <1.6 mm with an acceptable risk of early failure rate using microsurgery along with preventive haemostasis.

Cubital vein transposition for a distal radiocephalic fistula complicated by outflow obstruction.

INTRODUCTION: Outflow stenosis is a frequent complication of vascular access for hemodialysis. It may cause increased pressure within the angioaccess along with reduced blood flow. Elective treatment is percutaneous transluminal angioplasty; however, when a long occlusion (>2 cm) occurs, success and mid-term patency of endovascular treatment are uncertain. We describe a case series of patients with long occlusion of elbow outflow complicating an otherwise excellent forearm arteriovenous fistula, treated by a bypass across the elbow through cubital vein transposition. PATIENTS AND METHODS: Six consecutive patients have been treated between 2015 and 2017; all were referred because of either low flow, increased venous pressure, excessive bleeding time, or recirculation and were examined by duplex ultrasound. A total of 83% of patients showed associated thrombosis within the access. All procedures were performed under loco-regional anesthesia and preventive hemostasis. Surgical thrombectomy was also performed when needed. RESULTS: Immediate success was obtained in all but two patients converted in veno-venous polytetrafluoroethylene bypass. Post-operative blood flow increased from 316 to 878 mL/min. All patients were dialyzed through the forearm access immediately the day after surgery, without the need for central vein catheter. Overall, 75% of patients needed a percutaneous transluminal angioplasty of the veno-venous anastomosis within 6 months. Primary and secondary patency at 12 and 24 months were 25%-0% and 100%-100%, respectively. CONCLUSION: Outflow reconstruction through the elbow bypass by cubital vein transposition is a valuable resource to rescue radiocephalic arteriovenous fistula complicated by outflow obstruction, avoiding the use of an interim central vein catheter. Endovascular treatment is vital to maintain functional patency in the mid- and long term.

A new technique for measuring fistula flow using venous blood gas oxygen saturation in patients with a central venous catheter.

BACKGROUND: Doppler ultrasound (DU) monitoring early after arteriovenous fistula (AVF) creation allows the identification of low blood flow (Qa) requiring prompt revision, but it is costly (needs skilled operators and technical instruments) and is not available in all dialysis units. Therefore alternative first-line methods to measure Qa would be welcomed. We reasoned that once an AVF is created, an increment in central venous oxygen saturation (ScvO2) is predictable and proportional to Qa. METHODS: Accordingly, in patients receiving dialysis through a central venous catheter (CVC) in whom an AVF was created, we measured, by means of blood gas analysis, the ScvO2 increment before and after manual compression of the arteriovenous shunt and verified its correlation with DU-measured Qa. RESULTS: We sampled blood gas in 18 patients with CVC and AVF before and after 30 s manual compression of the AVF. ScvO2 averaged 70.5 ± 3% before and 65.2 ± 3% after AVF closure, with an average drop of 5.1 ± 3% (range 1-12). AVF Qa, which was measured within 24 h by means of DU, averaged 635 ± 349 mL/min (range 50-1300) and was strictly and positively correlated with ΔScvO2 (r = 0.954, P < 0.0001). CONCLUSIONS: Therefore we suggest that in patients with CVC and a newly created AVF, it is possible to monitor AVF Qa without DU by simply measuring blood gas and ΔScvO2. This technique is simple, cheap, repeatable, non-invasive and operator independent and represents a new useful screening test to detect delayed AVF access maturation deserving prompt DU measurement and surgical revision. It helps to quickly identify patients in urgent need of DU verification and possible surgical revision. Regrettably, it is applicable only in patients with CVC.