Long-term outcome of COVID-19 patients with acute kidney injury requiring kidney replacement therapy.

BACKGROUND: Limited data existed on the burden of coronavirus disease 2019 (COVID-19) renal complications and the outcomes of the most critical patients who required kidney replacement therapy (KRT) during intensive care unit (ICU) stay. We aimed to describe mortality and renal function at 90 days in patients admitted for COVID-19 and KRT. METHODS: A retrospective cohort study of critically ill patients admitted for COVID-19 and requiring KRT from March 2020 to January 2022 was conducted in an Italian ICU from a tertiary care hospital. Primary outcome was mortality at 90 days and secondary outcome was kidney function at 90 days. RESULTS: A cohort of 45 patients was analyzed. Mortality was 60% during ICU stay and increased from 64% at the time of hospital discharge to 71% at 90 days. Among 90-day survivors, 31% required dialysis, 38% recovered incompletely, and 31% completely recovered renal function. The probability of being alive and dialysis-free at 3 months was 22%. CONCLUSIONS: Critically ill patients with COVID-19 disease requiring KRT during ICU stay had elevated mortality rate at 90 days, with low probability of being alive and dialysis-free at 3 months. However, a non-negligible number of patients completely recovered renal function.

Safety of Citrate Anticoagulation in CKRT: Monocentric Experience of a Dynamic Protocol of Calcium Monitoring.

Regional Citrate Anticoagulation (RCA) is considered the first-line anticoagulation for Continuous Kidney Replacement Therapy (CKRT). The RCA requires strict protocols and trained staff to avoid unsafe use and ensure its benefit. We have analyzed all our CKRT prescriptions from December 2020 to April 2022 anonymously, collecting data on CKRT, lab tests, clinical conditions, and complications of RCA. In addition, in order to better detect citrate accumulation, we have performed an RCA protocol by reducing the CaTot/Ca2+ ratio cut-off from 2.50 to 2.40 and increasing the number of calcium checks according to its trend. Among the 374 patients in CKRT, 104 received RCA prescriptions, of which 11 (10.6%) were discontinued: 4 for the suspicion of citrate accumulation, 1 for the development of metabolic alkalosis, 1 for the shift to a different CKRT procedure due to the need for a higher bicarbonate dose, 4 for the elevation of hepatocytolysis indexes, and 1 due to a preemptive discontinuation following massive post-surgery bleeding. None of the patients have had citrate toxicity as indicated by a CaTot/Ca2+ greater than 2.50, and our protocol has allowed the early identification of patients who might develop clinical citrate toxicity.

Slow Continuous Ultrafiltration in Regional Citrate Anticoagulation Performed with a Standard Fluid Infusion Central Venous Catheter in Intensive Care Unit for Fluid Overload in Acute on Chronic Heart Failure: A Case Report.

Slow continuous ultrafiltration (SCUF) is an extracorporeal therapy able to reduce fluid overload in chronic or acute heart failure resistant to diuretics. An in-vitro study demonstrated the SCUF feasibility using a standard fluid infusion central venous catheter (CVC). We describe the clinical application of this SCUF in regional citrate anticoagulation (SCUF-RCA) in a patient admitted to the Intensive Care Unit for acute decompensate heart failure with severe systemic fluid overload resistant to diuretics. To avoid risks deriving from a new catheterization, we used a pre-existing multi-lumen CVC for drug administration to provide 10 h of SCUF-RCA with a blood flow of 35 mL/min and 100 mL/h of ultrafiltration with a final weight loss of 1 Kilogram without technical and clinical complications. The patient had a hemodynamics improvement with the diuresis recovery from the previous oliguria after the SCUF-RCA. This clinical case can open the use of the SCUF-RCA in the clinical practice to treat the fluid overload unresponsive to maximal diuretic therapy not exposing the patient to the risks and complications related to the use of SCUF with CVC for dialysis and systemic anticoagulation with heparin. Accordingly, this technique may be useful in the treatment of fluid overload in outpatients.

The Supporting Role of Combined and Sequential Extracorporeal Blood Purification Therapies in COVID-19 Patients in Intensive Care Unit.

Critical clinical forms of COVID-19 infection often include Acute Kidney Injury (AKI), requiring kidney replacement therapy (KRT) in up to 20% of patients, further worsening the outcome of the disease. No specific medical therapies are available for the treatment of COVID-19, while supportive care remains the standard treatment with the control of systemic inflammation playing a pivotal role, avoiding the disease progression and improving organ function. Extracorporeal blood purification (EBP) has been proposed for cytokines removal in sepsis and could be beneficial in COVID-19, preventing the cytokines release syndrome (CRS) and providing Extra-corporeal organ support (ECOS) in critical patients. Different EBP procedures for COVID-19 patients have been proposed including hemoperfusion (HP) on sorbent, continuous kidney replacement therapy (CRRT) with adsorbing capacity, or the use of high cut-off (HCO) membranes. Depending on the local experience, the multidisciplinary capabilities, the hardware, and the available devices, EBP can be combined sequentially or in parallel. The purpose of this paper is to illustrate how to perform EBPs, providing practical support to extracorporeal therapies in COVID-19 patients with AKI.

In vitro use of standard fluid infusion central venous catheter for slow continuous ultrafiltration feasibility assessment.

BACKGROUND: Slow continuous ultrafiltration (SCUF) by central venous catheter (CVC) for hemodialysis is a simple extracorporeal ultrafiltration that can reduce and control fluid overload in patients with chronic or acute chronic heart failure unresponsive to medical therapy. In order to avoid complications and risks related to the catheterization with a standard CVC for hemodialysis to provide the SCUF, considering that hospitalized patients affected by congestive heart failure commonly undergo CVC placement for medications delivering, we tested an in vitro model to use a standard CVC for infusion to perform SCUF. METHODS: We performed an in vitro SCUF experimental model through two different lumens of a triple (8Fr × 20 cm Tri-lumen catheter Kit-Envans Extra) and a quad-lumen CVC (8.5Fr × 20 cm Quad-lumen catheter kit-Benefis Medical Devices) commonly used in our Intensive Care Unit for fluids and medications infusions. We used Prismaflex with the HF-20 set (Baxter, IL, USA) to perform the SCUF treatment. RESULTS: Our in vitro data confirm the technical feasibility of the use of standard CVC for fluid infusion to perform a SCUF treatment with a theoretical weight loss of up to 200 ml/h by a blood flow ranging from 30 to 45 ml/min. CONCLUSIONS: The use of standard infusion CVC could be utilized in the intensive care unit to perform SCUF not exposing patients to the risks and complications related to the placement and permanence of CVC for hemodialysis.

The patient safety in extracorporeal blood purification treatments of critical patients.

Today, health systems are complex due to both the technological development in diagnostic and therapeutic procedures and the complexity of the patients that are increasingly older with several comorbidities. In any care setting, latent, organizational, and systematic errors can occur causing critical incident harmful for patients. Management of patients with acute kidney injury (AKI) requires a multidisciplinary approach for the diagnostic-therapeutic-rehabilitative path that can also require an extracorporeal blood purification treatment (EBPT). The complexity of these patients and EBPT require a clinical risk analysis and the introduction of protocols, procedures, operating instructions, and checklists to reduce clinical risk through promotion of the safety culture for all care providers. Caregivers must acquire a series of tools to evaluate the clinical risk in their reality to prevent incidents and customize patient safety in a proactive and reactive way. Established procedures that are made more needed by the COVID-19 pandemic can help to better manage patients in critical care area with intrinsic higher clinical risk. This review analyzes the communication and organizational aspects that need to be taken into consideration in the management of EBPT in a critical care setting by providing tools that can be used to reduce the clinical risk. This review is mostly addressed to all the caregivers involved in the EBPT in Critical Care Nephrology and in the Intensive Care Units.

Impact of different hemodiafiltration solutions on ionemia in long-term CRRT.

Critical patients with Acute Kidney Injury (AKI) requiring renal replacement therapy are in most cases eligible only for continuous modalities where the electrolyte balance control is a critical issue. The standard solutions used for hemodiafiltration, containing potassium at 2 mmol/L and no phosphorus, determines during the extended renal replacement therapy hypokalemia and hypophosphatemia. Therefore, solutions containing potassium and phosphate in physiological concentrations were formulated to avoid electrolyte imbalances and reduce ion alterations in prolonged treatments, these solutions are not routinely used in the standard clinical practice. To avoid electrolyte imbalances, we have first introduced in our practice two different solutions and then we have retrospectively analyzed the electrolyte balance upon these two solutions in order to identity the impact of these solutions on potassium and phosphate according to our clinical practice. We retrospectively analyzed 96 patients treated with Continuous Renal Replacement Therapy (CRRT) in the intensive care units (ICU) at Padua's University Hospital to evaluate the role on electrolyte balance of Phoxilium® and Prismasol 2® that differ in their composition and the need for electrolytes infusions. In the Phoxilium group the frequency of hypokalemia, hypophosphatemia, and the need of potassium and phosphate replacement were significantly reduced resulting in a reduction in complications, workload, and clinical risk associated with infusions of electrolytes. Our data demonstrated that the use of these two different hemodiafiltration solutions can reduce the occurrence of hypokalemia and hypophosphatemia during CRRT performing personalized treatments without the use of potassium and phosphate infusions.

High Blood Pressure Is Associated with Tubulointerstitial Damage along with Glomerular Damage in Glomerulonephritis. A large Cohort Study.

The key role of arterial hypertension in chonic kidney disease (CKD) progression is widely recognized, but its contribution to tubulointerstitial damage (TID) in glomerulonephritis (GN) remains uncertain. Hence, the objective of this study is to clarify whether TID is associated with glomerular damage, and whether the damage at the tubulointerstitial compartment is more severe in hypertensive patients. The study included retrospectively consecutive patients referred to the Nephrology Unit with diagnoses of primary glomerulonephritis, lupus nephritis (LN), and nephroangiosclerosis (NAS) at biopsy. At least six glomeruli per biopsy were analysed through light and immunofluorescence microscopy. Global glomerulosclerosis (GGS%), TID, and arteriolar hyalinosis (AH) were used as markers of CKD severity. Of the 448 patients of the cohort, 403 received a diagnosis of GN, with the remaining being diagnosed with NAS. Hypertension was found in 52% of the overall patients, with no significant differences among those with GN, and reaching 88.9% prevalence rate in NAS. The hypertensive patients with GN had more marked damage in glomerular and tubular compartments than normotensives independently of the amount of proteinuria. Moreover, hypertension and GGS% were found to be strongly associated with TID in GN. In GN patients, not only the severity of glomerular damage but also the extent of TID was associated with high blood pressure.

The Dialyzer Identification Code (DIC): A filter characteristics codification for dialyzer choice in renal replacement therapy.

The dialyzer is the core element of extracorporeal blood purification therapies where several processes take place depending on specific membrane characteristics. To date, the filter choice requires preliminary knowledge of all its characteristics as they cannot be easily deduced from the commercial trade name, hence the difficulty in identifying easily equivalent dialyzers and clearly comparing single-filter characteristics. The choice of improper dialyzers for a specific treatment can determine a less-effective blood purification and potentially harmful treatments. We aimed to propose a univocal and standardized alphanumeric string to summarize essential filter properties in the Dialyzer Identification Code (DIC). DIC clearly describes device characteristics and allows to compare different dialyzer performances without resorting to the technical data sheets. Therefore, the presence of the DIC on every device facilitates information retrieval on the dialyzer, its intended use, and can facilitate matching the dialysis modality to correct dialyzers achieving a personalized renal replacement therapy. The standard filter characteristics codification by the DIC may further optimize correct extracorporeal blood purification prescriptions and the use of equivalent filters from different providers avoiding treatment inefficiency, clinical complications, and improving patient safety.

A Continuous Renal Replacement Therapy Protocol for Patients with Acute Kidney Injury in Intensive Care Unit with COVID-19.

COVID-19 often leads to acute respiratory distress syndrome complicated by acute kidney injury (AKI). The indications for renal replacement therapy for these patients are those commonly accepted to treat AKI. We describe a continuous veno-venous haemodialysis (CVVHD) protocol for AKI, which aims to provide the best treatment according to the particular patient's and medical personnels' needs in biohazard settings with limited human and technological resources. We designed a CVVHD protocol with a high cut-off (HCO) filter in regional citrate anticoagulation (RCA). The HCO filter in diffusion determines the enhanced cytokines clearance with less filter clotting due to a lower filtration fraction. In our hospital, at the beginning of the pandemic outbreak, we treated seven COVID-19 patients with AKI stage 2 and 3 and recorded the circuit lifespan and the number of interventions on monitors. CVVHD in RCA appears to be safe, effective and easy to be performed in a biohazard scenario using lower blood flows and less bag changes with fluid savings, a biohazard reduction and sparing of resources. Although the data come from a very small cohort, our protocol seems related to a low mortality.

Evaluating Nephrocheck® as a Predictive Tool for Acute Kidney Injury.

Acute kidney injury (AKI) is a common complication in critically ill patients in the intensive settings with increased risks of short- and long-term complications and mortality. AKI is also associated with an increased length of stay in intensive care units (ICU) and worse kidney function recovery at hospital discharge. The management of AKI is one of the major challenges for nephrologists and intensivists overall for its early diagnosis. The current KDIGO criteria used to define AKI include the serum creatinine and urinary output that are neither sensitive nor specific markers of kidney function, since they can be altered only after hours from the kidney injury. In order to allow an early AKI detection, in the last years, several studies focused on the identification of new biomarkers. Among all these markers, urinary insulin-like growth factor-binding protein (IGFBP-7) and tissue inhibitor of metalloproteinase (TIMP-2) have been proven as the best-performing and have been proposed as a predictive tool for the AKI detection in the critical settings in order to perform an early diagnosis. Patients undergoing major surgery, cardiac surgery, those with hemodynamic instability or those with sepsis are believed to be the top priority patient populations for the biomarker test. In this view, the urinary [TIMP-2] x [IGFBP-7] becomes an important tool for the early detection of patients at high risk for AKI and its integration with the local ICU experience has to provide a multidisciplinary management of AKI with the institution of a rapid response team in order to assess patients and customize AKI management.

Intravenous ferric carboxymaltose for iron deficiency anemia in dialysis patients: Effect of a new protocol adopted for a hemodialysis limited assistance center.

Iron and erythropoietin deficiencies are determinants of anemia in chronic kidney disease. In hemodialysis (HD) patients, intravenous (IV) iron is associated with a greater hemoglobin (Hb) production and better erythropoietin response but may be associated to hypersensitivity reaction. After the 2013 European Medicines Agency report regarding early detection/management of iron allergic reactions, IV iron administration dramatically reduced in Italian Hemodialysis-Limited-Assistance-Centre (HD-CAL) where a physician is present only once a week. Objective of the study was providing an effective and secure IV iron administration protocol for HD-CAL patients. IV ferric carboxymaltose (FCM) administration was more effective and better tolerated than sodium ferric gluconate for iron deficiency correction and resolution of anemia in 24 patients undergoing HD in our HD-CAL. Six months of FCM IV treatment once a week increased ferritin and Hb compared to sodium ferric gluconate once a week leading to decreased erythropoietin consumption from 24 000 to 15 000 U/patient/week with an erythropoietin annual expense reduction. No blood transfusions, gastrointestinal intolerance or other adverse effects were reported. The FCM IV administration protocol for our HD-CAL patients was safe and no adverse events were reported, resulting in significantly increased ferritin, transferrin saturation, and Hb levels, reduction of erythropoietin requirements, and consequently reduction of erythropoietin expenses.

Ultrasound for the Clinical Management of Vascular Access Cannulation and Needle Position in Hemodialysis Patients.

A native arteriovenous fistula (AVF) is the vascular access of choice for hemodialysis (HD) treatment. Compared with other types of vascular access such as grafts and central venous catheters, it functions longer and is associated with a lower risk of complications. The aim of the study described here was to assess, in an HD population, the position of the fistula needles during an HD session and evaluate the role of ultrasound in the management of AVF puncture. Forty-five consecutive chronic HD patients with an AVF or an arteriovenous vascular graft were included in the study for ultrasound evaluation. Each patient underwent an ultrasound evaluation during HD treatment to assess the position of the needles inside the vascular access. The ultrasound evaluation revealed that 81.8% of the traditional needles were incorrectly adjacent to the vessel walls, in the absence of clinical symptoms or hemodynamic alterations detectable on the dialysis monitor. A greater frequency of malpositioning has been observed for needles in the arterial portion of the vascular access, closer to the anastomosis. The absence of clinically detectable signs of venipuncture-related complications does not ensure correct positioning of the needles within the AVF. Ultrasound evaluation may not only resolve suboptimal cannulation problems of new or complicated vascular accesses but may also be useful in the prevention of acute and chronic damage to the AVF.

[Proactive approach for the patient safety in the extracorporeal blood purification treatments in nephrology].

Latent, systemic, organizational and clinical errors may impend on a single clinical reality that is considered safe. These errors may lead to the occurrence of a critical event with possible damage to the patient. The patients' greater clinical complexity, in the field of AKI or CKD, requires a multidisciplinary approach that involves nephrologists and other specialists in the diagnostic-therapeutic-rehabilitative path requiring the administration of personalized extracorporeal blood purification treatments. In consideration of the comorbidities of these patients, and their increasing management complexity, the Patient Safety becomes a priority objective in these therapeutic pathways. For all caregivers, it is therefore necessary to be able to acquire a series of tools suitable for the analysis of the clinical risk present in each individual nephrological realities in order to introduce a series of measures and tools for the analysis and prevention of possible errors that can determine an event. The aim of this paper is to introduce the problem of patient safety in the extracorporeal blood purification treatments for the initial analysis of local clinical risks, and the prevention of errors in the clinical practice in nephrology by introducing specific procedures and check lists. This work is addressed to all the caregivers involved in the Nephrology care.