Extracorporeal Immunomodulation Therapy in Acute Chronic Liver Failure With Multiorgan Failure: First in Human Use

Two patients presented with acute on chronic liver failure and multiorgan failure and, as typical for this disorder, they presented with hyperinflammation and anticipated high mortality rates. Both cases were diagnosed with hepatorenal syndrome (HRS). Under a FDA approved Investigational Device Exemption clinical trial, they underwent treatment with an extracorporeal cell-directed immunomodulatory device, called selective cytopheretic device. Both patients showed rapid clinical improvement associated with a decline in elevated blood cytokine concentrations and diminution of activation levels of circulating leukocytes. On follow-up, one patient was alive at day 90 after treatment and undergoing liver transplantation evaluation and the other patient had a successful liver transplantation 6 days after selective cytopheretic device therapy ended. These cases represent the first in human evaluation of extracorporeal cell-directed immunomodulation therapy in acute on chronic liver failure with successful clinical outcomes in a disorder with dismal prognosis.

Translation of immunomodulatory therapy to treat chronic heart failure: Preclinical studies to first in human

BACKGROUND

Inflammation has been associated with progression and complications of chronic heart failure (HF) but no effective therapy has yet been identified to treat this dysregulated immunologic state. The selective cytopheretic device (SCD) provides extracorporeal autologous cell processing to lessen the burden of inflammatory activity of circulating leukocytes of the innate immunologic system.

AIM

The objective of this study was to evaluate the effects of the SCD as an extracorporeal immunomodulatory device on the immune dysregulated state of HF. HF.

METHODS AND RESULTS

SCD treatment in a canine model of systolic HF or HF with reduced ejection fraction (HFrEF) diminished leukocyte inflammatory activity and enhanced cardiac performance as measured by left ventricular (LV) ejection fraction and stroke volume (SV) up to 4 weeks after treatment initiation. Translation of these observations in first in human, proof of concept clinical study was evaluated in a patient with severe HFrEFHFrEF ineligible for cardiac transplantation or LV LV assist device (LVAD) due to renal insufficiency and right ventricular dysfunction. Six hour SCD treatments over 6 consecutive days resulted in selective removal of inflammatory neutrophils and monocytes and reduction in key plasma cytokines, including tumor necrosis factor-alpha (TNF-α),), interleukin (IL)-6, IL-8, and monocyte chemoattractant protein (MCP)-1. These immunologic changes were associated with significant improvements in cardiac power output, right ventricular stroke work index, cardiac index and LVSV index…. Stabilization of renal function with progressive volume removal permitted successful LVAD implantation.

CONCLUSION

This translational research study demonstrates a promising immunomodulatory approach to improve cardiac performance in HFrEFHFrEF and supports the important role of inflammation in the progression of HFHF.

Management of dysnatremias with continuous renal replacement therapy

Disorders of serum sodium concentration are common in critically ill patients who may have concomitant acute kidney injury, chronic kidney disease, or end-stage kidney disease. Many of these patients may require customized serum sodium level management with dialysis which, if not strictly controlled, can lead to significant complications. Thus, controlled correction of the serum sodium level is necessary to avoid the development of osmotic demyelination syndrome in hyponatremic patients and dialysis disequilibrium syndrome in hypernatremic patients. Continuous renal replacement therapy offers unique benefits through the ability to slowly and safely correct dysnatremias that can be tailored to specific patient needs and should be considered in select patients.

Regional citrate anticoagulation "non-shock" protocol with pre-calculated flow settings for patients with at least 6 L/hour liver citrate clearance

BACKGROUND

Regional citrate anticoagulation (RCA) for the prevention of clotting of the extracorporeal blood circuit during continuous kidney replacement therapy (CKRT) has been employed in limited fashion because of the complexity and complications associated with certain protocols. Hypertonic citrate infusion to achieve circuit anticoagulation results in variable systemic citrate- and sodium load and increases the risk of citrate accumulation and hypernatremia. The practice of "single starting calcium infusion rate for all patients" puts patients at risk for clinically significant hypocalcemia if filter effluent calcium losses exceed replacement. A fixed citrate to blood flow ratio, personalized effluent and pre-calculated calcium infusion dosing based on tables derived through kinetic analysis enable providers to use continuous veno-venous hemo-diafiltration (CVVHDF)-RCA in patients with liver citrate clearance of at least 6 L/h.

METHODS

This was a single-center prospective observational study conducted in intensive care unit patients triaged to be treated with the novel pre-calculated CVVHDF-RCA "Non-shock" protocol. RCA efficacy outcomes were time to first hemofilter loss and circuit ionized calcium (iCa) levels. Safety outcomes were surrogate of citrate accumulation (TCa/iCa ratio) and the incidence of acid-base and electrolyte complications.

RESULTS

Of 53 patients included in the study, 31 (59%) had acute kidney injury and 12 (22.6%) had the diagnosis of cirrhosis at the start of CVVHDF-RCA. The median first hemofilter life censored for causes other than clotting exceeded 70 h. The cumulative incidence of hypernatremia (Na > 148 mM), metabolic alkalosis (HCO3- > 30 mM), hypocalcemia (iCa < 0.9 mM) and hypercalcemia (iCa > 1.5 mM) were 1/47 (1%), 0/50 (0%), 1/53 (2%), 1/53 (2%) respectively and were not clinically significant. The median (25th-75th percentile) of the highest TCa/iCa ratio for every 24-h interval on CKRT was 1.99 (1.91-2.13).

CONCLUSIONS

The fixed citrate to blood flow ratio, as opposed to a titration approach, achieves adequate circuit iCa (< 0.4 mm/L) for any hematocrit level and plasma flow. The personalized dosing approach for calcium supplementation based on pre-calculated effluent calcium losses as opposed to the practice of "one starting dose for all" reduces the risk of clinically significant hypocalcemia. The fixed flow settings achieve clinically desirable steady state systemic electrolyte levels.

Technology Innovations in Continuous Kidney Replacement Therapy: The Clinician's Perspective

Continuous kidney replacement therapy (CKRT) has improved remarkably since its first implementation as continuous arteriovenous hemofiltration in the 1970s. However, when looking at the latest generation of CKRT machines, one could argue that clinical deployment of breakthrough innovations by device manufacturers has slowed in the last decade. Simultaneously, there has been a steady accumulation of clinical knowledge using CKRT as well as a multitude of therapeutic and diagnostic innovations in the dialysis and broader intensive care unit technology fields adaptable to CKRT. These include multiple different anticlotting measures; cloud-computing for optimized treatment prescribing and delivered therapy data collection and analysis; novel blood purification techniques aimed at improving the severe multiorgan dysfunction syndrome; and real-time sensing of blood and/or filter effluent composition. The authors present a view of how CKRT devices and programs could be reimagined incorporating these innovations to achieve specific measurable clinical outcomes with personalized care and improved simplicity, safety, and efficacy of CKRT therapy.

Regional Citrate Anticoagulation Protocol for Patients with Presumed Absent Citrate Metabolism

Background

Regional citrate anticoagulation (RCA) is not recommended in patients with shock or severe liver failure. We designed a protocol with personalized precalculated flow settings for patients with absent citrate metabolism that abrogates risk of citrate toxicity, and maintains neutral continuous KRT (CKRT) circuit calcium mass balance and normal systemic ionized calcium levels.

Methods

A single-center prospective cohort study of patients in five adult intensive care units triaged to the CVVHDF-RCA "Shock" protocol.

Results

Of 31 patients included in the study, 30 (97%) had AKI, 16 (52%) had acute liver failure, and five (16%) had cirrhosis at the start of CKRT. The median lactate was 5 mmol/L (interquartile range [IQR], 3.2-10.7), AST 822 U/L (IQR, 122-2950), ALT 352 U/L (IQR, 41-2238), total bilirubin 2.7 mg/dl (IQR, 1.0-5.1), and INR two (IQR, 1.5-2.6). The median first hemofilter life censored for causes other than clotting exceeded 70 hours. The cumulative incidence of hypernatremia (Na >148 mM), metabolic alkalosis (HCO3- >30 mM), and hypophosphatemia (P<2 mg/dl) were one out of 26 (4%), zero out of 30 (0%), and one out of 30 (3%), respectively, and were not clinically significant. Mild hypocalcemia occurred in the first 4 hours in two out of 31 patients, and corrected by hour 6 with no additional Ca supplementation beyond the per-protocol administered Ca infusion. The maximum systemic total Ca (tCa; mM)/ionized Ca (iCa; mM) ratio never exceeded 2.5.

Conclusions

The Shock protocol can be used without contraindications and is effective in maintaining circuit patency with a high, fixed ACDA infusion rate to blood flow ratio. Keeping single-pass citrate extraction on the dialyzer >0.75 minimizes the risk of citrate toxicity even in patients with absent citrate metabolism. Precalculated, personalized dosing of the initial Ca-infusion rate from a table on the basis of the patient's albumin level and the filter effluent flow rate maintains neutral CKRT circuit calcium mass balance and a normal systemic iCa level.

Treatment of Cytokine Storm in COVID-19 Patients With Immunomodulatory Therapy

Observational evidence suggests that excessive inflammation with cytokine storm may play a critical role in development of acute respiratory distress syndrome (ARDS) in COVID-19. We report the emergency use of immunomodulatory therapy utilizing an extracorporeal selective cytopheretic device (SCD) in two patients with elevated serum interleukin (IL)-6 levels and refractory COVID-19 ARDS requiring extracorporeal membrane oxygenation (ECMO). The two patients were selected based on clinical criteria and elevated levels of IL-6 (>100 pg/ml) as a biomarker of inflammation. Once identified, emergency/expanded use permission for SCD treatment was obtained and patient consented. Six COVID-19 patients (four on ECMO) with severe ARDS were also screened with IL-6 levels less than 100 pg/ml and were not treated with SCD. The two enrolled patients' PaO2/FiO2 ratios increased from 55 and 58 to 200 and 192 at 52 and 50 hours, respectively. Inflammatory indices also declined with IL-6 falling from 231 and 598 pg/ml to 3.32 and 116 pg/ml, respectively. IL-6/IL-10 ratios also decreased from 11.8 and 18 to 0.7 and 0.62, respectively. The two patients were successfully weaned off ECMO after 17 and 16 days of SCD therapy, respectively. The results observed with SCD therapy on these two critically ill COVID-19 patients with severe ARDS and elevated IL-6 is encouraging. A multicenter clinical trial is underway with an FDA-approved investigational device exemption to evaluate the potential of SCD therapy to effectively treat COVID-19 intensive care unit patients.

Deployment of a New CRRT/PIRRT Device during the COVID-19 Pandemic Emergency: Organizational Challenges and Implementation Results

INTRODUCTION

The coronavirus disease 2019 (COVID-19) pandemic led to increased demand nationwide for dialysis equipment, including supplies and machines. To meet the demand in our institution, our surge plan included rapid mobilization of a novel continuous renal replacement treatment (CRRT) machine named SAMI. The SAMI is a push-pull filtration enhanced dialysis machine that can conjugate extremely high single-pass solute removal efficiency with very precise fluid balance control.

MATERIAL AND METHODS

Machine assembly was conducted on-site by local biomedical engineers with remote assistance by the vendor. One 3-h virtual training session of 3 dialysis nurses was conducted before SAMI deployment. The SAMI was deployed in prolonged intermittent replacement therapy (PIRRT) mode to maximize patients covered per machine per day. Live on-demand vendor support was provided to troubleshoot any issues for the first few cases. After 4 weeks of the SAMI implementation, data on treatments with the SAMI were collected, and a questionnaire was provided to the nurse trainees to assess device usability.

RESULTS

On-site installation of the SAMI was accomplished with remote assistance. Delivery of remote training was successfully achieved. 23 PIRRT treatments were conducted in 10 patients. 7/10 of patients had CO-VID-19. The median PIRRT dose was 50 mL/kg/h (IQR [interquartile range] 44 - 62 mL/kg/h), and duration of the treatment was 8 h (IQR 6.3 - 8 h). Solute control was adequate. The user response was favorable to the set of usability questions involving user interface, on-screen instructions, machine setup, troubleshooting, and the ease of moving the machine.

CONCLUSION

Assembly of the SAMI and training of nurses remotely are possible when access to vendor employees is restricted during states of emergency. The successful deployment of the SAMI in our institution during the pandemic with only 3-h virtual training supports that operating the SAMI is simple and safe.

Continuous Renal Replacement Therapy for the Management of Acid-Base and Electrolyte Imbalances in Acute Kidney Injury

Continuous renal replacement therapy (CRRT) is used to manage electrolyte and acid-base imbalances in critically ill patients with acute kidney injury. Although a standard solution and prescription is acceptable in most clinical circumstances, specific disorders may require a tailored approach such as adjusting fluid composition, regulating CRRT dose, and using separate intravenous infusions to mitigate and correct these disturbances. Errors in fluid prescription, compounding, or delivery can be rapidly fatal. This article provides an overview of the principles of acid-base and electrolyte management using CRRT.

A Multi-Center, Randomized, Controlled, Pivotal Study to Assess the Safety and Efficacy of a Selective Cytopheretic Device in Patients with Acute Kidney Injury

OBJECTIVE

Acute kidney injury (AKI) is a highly morbid condition in critically ill patients that is associated with high mortality. Previous clinical studies have demonstrated the safety and efficacy of the Selective Cytopheretic Device (SCD) in the treatment of AKI requiring continuous renal replacement therapy in the intensive care unit (ICU).

DESIGN, SETTING, PATIENTS

A randomized, controlled trial of 134 ICU patients with AKI, 69 received continuous renal replacement therapy (CRRT) alone and 65 received SCD therapy.

RESULTS

No significant difference in 60-day mortality was observed between the treated (27/69; 39%) and control patients (21/59; 36%, with six patients lost to follow up) in the intention to treat (ITT) analysis. Of the 19 SCD subjects (CRRT+SCD) and 31 control subjects (CRRT alone) who maintained a post-filter ionized calcium (iCa) level in the protocol's recommended range (≤ 0.4 mmol/L) for greater or equal to 90% of the therapy time, 60-day mortality was 16% (3/19) in the SCD group compared to 41% (11/27) in the CRRT alone group (p = 0.11). Dialysis dependency showed a borderline statistically significant difference between the SCD treated versus control CRRT alone patients maintained for ≥ 90% of the treatment in the protocol's recommended (r) iCa target range of ≤ 0.4 mmol/L with values of, 0% (0/16) and 25% (4/16), respectively (P = 0.10). When the riCa treated and control subgroups were compared for a composite index of 60 day mortality and dialysis dependency, the percentage of SCD treated subjects was 16% versus 58% in the control subjects (p<0.01). The incidence of serious adverse events did not differ between the treated (45/69; 65%) and control groups (40/65; 63%; p = 0·86).

CONCLUSION

SCD therapy may improve mortality and reduce dialysis dependency in a tightly controlled regional hypocalcaemic environment in the perfusion circuit.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01400893 http://clinicaltrials.gov/ct2/show/NCT01400893.

Treatment of severe hyponatremia in patients with kidney failure: role of continuous venovenous hemofiltration with low-sodium replacement fluid

Patients with hypervolemic hyponatremia and kidney failure pose a special therapeutic challenge. Hemodialysis to correct volume overload, azotemia, and abnormal electrolyte levels will result in rapid correction of serum sodium concentration and place the patient at risk for osmotic demyelination syndrome. We present a patient with acute kidney injury and severe hypervolemic hypotonic hyponatremia (serum sodium<100 mEq/L) who was treated successfully with continuous venovenous hemofiltration. This teaching case illustrates the limitations of hemodialysis and demonstrates how to regulate the sodium correction rate by single-pool sodium kinetic modeling during continuous venovenous hemofiltration. Two methods to adjust the replacement fluid to achieve the desired sodium concentration are outlined.

Considerations in the critically ill ESRD patient

ESRD patients are admitted more frequently to intensive care units (ICUs) and have higher mortality risks than the general population, and the main causes of critical illness among ESRD patients are cardiovascular events, sepsis, and bleeding. Once in the ICU, hemodynamic stabilization and fluid-electrolyte management pose major challenges in oligoanuric patients. Selection of renal replacement therapy (RRT) modality is influenced by the outpatient modality and access, as well as severity of illness, renal provider experience, and ICU logistics. Currently, most patients receive intermittent hemodialysis or continuous RRT with temporary vascular access catheters. Acute peritoneal dialysis (PD) is less frequently utilized, and utility of outpatient PD is reduced after an ICU admission. Thus, preservation of current vascular accesses, while limiting venous system damage for future access creations, is relevant. Also, dosing of small-solute clearance with urea kinetic modeling is difficult and may be supplanted by novel online clearance techniques. Medication dosing, coordinated with delivered RRT, is essential for septic patients treated with antibiotics. A comprehensive, standardized approach by a multidisciplinary team of providers, including critical care specialists, nephrologists, and pharmacists, represents a nexus of care that can reduce readmission rates, morbidity, and mortality of vulnerable ESRD patients.

Characterization of the rat mesangial cell type 2 sulfonylurea receptor

BACKGROUND

Sulfonylurea receptors are classified as either high-affinity type 1 (SUR1) or low-affinity type 2 receptors (SUR2), and the gene expression of SURs has recently been demonstrated in kidney. However, functional data regarding a renal SUR are lacking. We previously demonstrated that mesangial cell (MC) gene and protein expression of extracellular matrix components were up-regulated by the sulfonylurea, tolazamide. After noting this biological response, we next sought to investigate the presence of a sulfonylurea receptor in rat MCs.

METHODS

Equilibrium binding studies employing [3H]glibenclamide as a ligand were performed on crude MC membrane preparations. Gene expression for SUR was explored by Northern analysis of cultured MCs and whole kidney tissue. The effect of sulfonylurea on intracellular Ca2+ in MCs was assayed by spectrofluorometry, and glibenclamide-induced changes in the contractility of MCs were assessed.

RESULTS

MCs bound [3H]glibenclamide with a KD of 2.6 microM and a Bmax of 30.4 pmol/mg protein as determined by Scatchard analysis. Three SUR2 transcripts were detected in MCs. A major transcript was detected at 5.5 kb and minor transcripts at 7.5 and 8.6 kb. Following sulfonylurea treatment of MCs, real-time videomicroscopy revealed intense MC contraction, coinciding with oscillatory increments of intracellular Ca2+ concentration. Further evidence of sulfonylurea-induced MC contraction was demonstrated by glibenclamide-induced deformation of a silicone rubber substrate.

CONCLUSIONS

These results demonstrate that SUR2 resides on MCs. Functional activation of this receptor by sulfonylurea induces Ca2+ transients that result in MC contraction.