Cardiogenic shock and chronic kidney disease: Dangerous liaisons.

BACKGROUND: Chronic kidney disease (CKD) is one of the leading causes of death worldwide, closely interrelated with cardiovascular diseases, ultimately leading to the failure of both organs - the so-called "cardiorenal syndrome". Despite this burden, data related to cardiogenic shock outcomes in CKD patients are scarce. METHODS: FRENSHOCK (NCT02703038) was a prospective registry involving 772 patients with cardiogenic shock from 49 centres. One-year outcomes (rehospitalization, death, heart transplantation, ventricular assist device) were analysed according to history of CKD at admission and were adjusted on independent predictive factors. RESULTS: CKD was present in 164 of 771 patients (21.3%) with cardiogenic shock; these patients were older (72.7 vs. 63.9years) and had more comorbidities than those without CKD. CKD was associated with a higher rate of all-cause mortality at 1month (36.6% vs. 23.2%; hazard ratio 1.39, 95% confidence interval 1.01-1.9; P=0.04) and 1year (62.8% vs. 40.5%, hazard ratio 1.39, 95% confidence interval 1.09-1.77; P<0.01). Patients with CKD were less likely to be treated with norepinephrine/epinephrine or undergo invasive ventilation or receive mechanical circulatory support, but were more likely to receive renal replacement therapy (RRT). RRT was associated with a higher risk of all-cause death at 1month and 1year regardless of baseline CKD status. CONCLUSIONS: Cardiogenic shock and CKD are frequent "cross-talking" conditions with limited therapeutic options, resulting in higher rates of death at 1month and 1year. RRT is a strong predictor of death, regardless of preexisting CKD. Multidisciplinary teams involving cardiac and kidney physicians are required to provide integrated care for patients with failure of both organs.

Risk factors and outcomes in patients who switched from peritoneal dialysis to physician-oriented or patient-oriented kidney replacement therapy.

BACKGROUND: We aimed to compare the cardiovascular events and mortality in patients who underwent either physician-oriented or patient-oriented kidney replacement therapy (KRT) conversion due to discontinuation of peritoneal dialysis (PD). METHODS: Patients with end-stage kidney disease who were receiving PD and required a switch to an alternative KRT were included. They were divided into physician-oriented group or patient-oriented group based on the decision-making process. Logistic regression analysis was used to explore the influencing factors related to KRT conversion in PD patients. The association of physician-oriented or patient-oriented KRT conversion with outcomes after the conversion was assessed by using Cox proportional hazards models. RESULTS: A total of 257 PD patients were included in the study. The median age at catheterization was 35 years. 69.6% of the participants were male. The median duration of PD was 20 months. 162 participants had patient-oriented KRT conversion, while 95 had physician-oriented KRT conversion. Younger patients, those with higher education levels, higher income, and no diabetes were more likely to have patient-oriented KRT conversion. Over a median follow-up of 39 months, 40 patients experienced cardiovascular events and 16 patients died. Physician-oriented KRT conversion increased nearly 3.8-fold and 4.0-fold risk of cardiovascular events and death, respectively. After adjusting for confounders, physician-oriented KRT conversion remained about a 3-fold risk of cardiovascular events. CONCLUSION: Compared to patient-oriented KRT conversion, PD patients who underwent physician-oriented conversion had higher risks of cardiovascular events and all-cause mortality. Factors included age at catheterization, education level, annual household income, and history of diabetes mellitus.

Personalizing renal replacement therapy initiation in the intensive care unit: a reinforcement learning-based strategy with external validation on the AKIKI randomized controlled trials.

OBJECTIVE: The timely initiation of renal replacement therapy (RRT) for acute kidney injury (AKI) requires sequential decision-making tailored to individuals' evolving characteristics. To learn and validate optimal strategies for RRT initiation, we used reinforcement learning on clinical data from routine care and randomized controlled trials. MATERIALS AND METHODS: We used the MIMIC-III database for development and AKIKI trials for validation. Participants were adult ICU patients with severe AKI receiving mechanical ventilation or catecholamine infusion. We used a doubly robust estimator to learn when to start RRT after the occurrence of severe AKI for three days in a row. We developed a "crude strategy" maximizing the population-level hospital-free days at day 60 (HFD60) and a "stringent strategy" recommending RRT when there is significant evidence of benefit for an individual. For validation, we evaluated the causal effects of implementing our learned strategies versus following current best practices on HFD60. RESULTS: We included 3748 patients in the development set and 1068 in the validation set. Through external validation, the crude and stringent strategies yielded an average difference of 13.7 [95% CI -5.3 to 35.7] and 14.9 [95% CI -3.2 to 39.2] HFD60, respectively, compared to current best practices. The stringent strategy led to initiating RRT within 3 days in 14% of patients versus 38% under best practices. DISCUSSION: Implementing our strategies could improve the average number of days that ICU patients spend alive and outside the hospital while sparing RRT for many. CONCLUSION: We developed and validated a practical and interpretable dynamic decision support system for RRT initiation in the ICU.

Uplift modeling to predict individual treatment effects of renal replacement therapy in sepsis-associated acute kidney injury patients.

Renal replacement therapy (RRT) is a crucial treatment for sepsis-associated acute kidney injury (S-AKI), but it is uncertain which S-AKI patients should receive immediate RRT. Identifying the characteristics of patients who may benefit the most from RRT is an important task. This retrospective study utilized a public database and enrolled S-AKI patients, who were divided into RRT and non-RRT groups. Uplift modeling was used to estimate the individual treatment effect (ITE) of RRT. The validity of different models was compared using a qini curve. After labeling the patients in the validation cohort, we characterized the patients who would benefit the most from RRT and created a nomogram. A total of 8289 patients were assessed, among whom 591 received RRT, and 7698 did not receive RRT. The RRT group had a higher severity of illness than the non-RRT group, with a Sequential Organ Failure Assessment (SOFA) score of 9 (IQR 6,11) vs. 5 (IQR 3,7). The 28-day mortality rate was higher in the RRT group than the non-RRT group (34.83% vs. 14.61%, p < 0.0001). Propensity score matching (PSM) was used to balance baseline characteristics, 458 RRT patients and an equal number of non-RRT patients were enrolled for further research. After PSM, 28-day mortality of RRT and non-RRT groups were 32.3% vs. 39.3%, P = 0.033. Using uplift modeling, we found that urine output, fluid input, mean blood pressure, body temperature, and lactate were the top 5 factors that had the most influence on RRT effect. The area under the uplift curve (AUUC) of the class transformation model was 0.068, the AUUC of SOFA was 0.018, and the AUUC of Kdigo-stage was 0.050. The class transformation model was more efficient in predicting individual treatment effect. A logistic regression model was developed, and a nomogram was drawn to predict whether an S-AKI patient can benefit from RRT. Six factors were taken into account (urine output, creatinine, lactate, white blood cell count, glucose, respiratory rate). Uplift modeling can better predict the ITE of RRT on S-AKI patients than conventional score systems such as Kdigo and SOFA. We also found that white blood cell count is related to the benefits of RRT, suggesting that changes in inflammation levels may be associated with the effects of RRT on S-AKI patients.

Continuous renal replacement therapy and survival in acute liver failure: A systematic review and meta-analysis.

OBJECTIVE: Acute liver failure (ALF) is a rare syndrome leading to significant morbidity and mortality. An important cause of mortality is cerebral edema due to hyperammonemia. Different therapies for hyperammonemia have been assessed including continuous renal replacement therapy (CRRT). We conducted a systematic review and meta-analysis to determine the efficacy of CRRT in ALF patients. MATERIALS AND METHODS: We searched MEDLINE, EMBASE, Cochrane Library, and Web of Science. Inclusion criteria included adult patients admitted to an ICU with ALF. Intervention was the use of CRRT for one or more indications with the comparator being standard care without the use of CRRT. Outcomes of interest were overall survival, transplant-free survival (TFS), mortality and changes in serum ammonia levels. RESULTS: In total, 305 patients underwent CRRT while 1137 patients did not receive CRRT. CRRT was associated with improved overall survival [risk ratio (RR) 0.83, 95% confidence interval (CI) 0.70-0.99, p-value 0.04, I2 = 50%] and improved TFS (RR 0.65, 95% CI 0.49-0.85, p-value 0.002, I2 = 25%). There was a trend towards higher mortality with no CRRT (RR 1.24, 95% CI 0.84-1.81, p-value 0.28, I2 = 37%). Ammonia clearance data was unable to be pooled and was not analyzable. CONCLUSION: Use of CRRT in ALF patients is associated with improved overall and transplant-free survival compared to no CRRT.

The aetiology, risk factors and outcome of Acute Kidney Injury in patients requiring Kidney Replacement Therapy: A prospective single center experience.

Objective: To find out the causes, associated leading factors and impact of kidney replacement therapy on patients hospitalised for acute kidney injury in a tertiary care setting. METHODS: The prospective, cross-sectional study was conducted at the Sindh Institute of Urology and Transplantation, Karachi, from January 1 to March 31, 2022, and comprised patients of either gender aged 18 or more years presenting with acute kidney injury as per the Kidney Disease Improving Global Outcomes criteria and required kidney replacement therapy. Complete, partial or no recovery was the main outcome parameter noted at the end of 90 days. Possible aetiologies were identified and categorised as pre-renal, renal and post-renal aetiologies. Risk factors for acute kidney injury were recorded, including age, gender and co-morbidities. Data was analysed using SPSS 22. RESULTS: Of the 210 patients with mean age 46.1±14.24 years, 109(52%) were males and 101(48%) were females (p>0.05). Hypertension was the most common comorbidity 98(46.8%), followed by diabetes mellitus 75(35.7%) and underlying chronic kidney disease 55(26.2%). Multiple therapeutic interventions were required, including vasopressors in 101(48.1%) patients and mechanical ventilation in 31(14.8%). Renal failure due to intrinsic renal aetiology was the most common 98(46.7%), followed by post-renal aetiology 61(29%). There was no significant association between outcomes and aetiologies (p>0.05). There was increase in chronic kidney disease cases from 55(26.2%) patients at baseline to 107(50.9%) at the end of 90 days. Complete recovery was noted in 71(33.8%) patients, partial in 73(34.76%), no recovery in 34(16.1%) patients who required maintenance kidney replacement therapy, and 32(15.2%) patients died. Conclusion: Complete recovery after 90 days of kidney replacement therapy was observed in one-third of the patients. Intrinsic renal aetiology was the most prevalent, and hypertension was the most common comorbidity.

Long-term outcomes of lung transplantation requiring renal replacement therapy: A single-center experience.

BACKGROUND: Life-long immunosuppressive therapy after lung transplantation (LT) may lead to end-stage renal disease (ESRD), requiring renal replacement therapy (RRT). We aimed to investigate the characteristics and long-term outcomes of patients undergoing LT and requiring RRT. METHODS: This study was a single-center, retrospective cohort study. The patients were divided into the RRT (n = 15) and non-RRT (n = 170) groups. We summarized the clinical features of patients in the RRT group and compared patient characteristics, overall survival, and chronic lung allograft dysfunction (CLAD)-free survival between the two groups. RESULTS: The cumulative incidences of ESRD requiring RRT after LT at 5, 10, and 15 years were 0.8 %, 7.6 %, and 25.2 %, respectively. In the RRT group, all 15 patients underwent hemodialysis but not peritoneal dialysis, and two patients underwent living-donor kidney transplantation. The median follow-up period was longer in the RRT group than in the non-RRT group (P < 0.001). The CLAD-free survival and overall survival did not differ between the two groups. The 5-year survival rate even after the initiation of hemodialysis was 53.3 %, and the leading cause of death in the RRT group was infection. CONCLUSIONS: Favorable long-term outcomes can be achieved by RRT for ESRD after LT.

Let's stop talking about 'citrate toxicity'.

PURPOSE OF REVIEW: Continuous renal replacement therapy (CRRT) is a vital medical intervention used in critically ill patients with acute kidney injury (AKI). One of the key components of adequate clearance with CRRT is the use of anticoagulants to prevent clotting of the extracorporeal circuit. Regional citrate anticoagulation is the most often recommended modality. The term 'citrate toxicity' is used to describe potential adverse effects of accumulation of citrate and subsequent hypocalcemia. However, citrate is itself not inherently toxic. The term and diagnosis of citrate toxicity are questioned in this review. RECENT FINDINGS: Citrate is being increasingly used for regional anticoagulation of the CRRT circuit. Citrate accumulation is infrequent and can cause hypocalcemia and metabolic alkalosis, which are potential adverse effects. Citrate itself, however, is not a toxic molecule. The term 'citrate toxicity' has been used to denote hypocalcemia and metabolic acidosis. However, citrate administration is well known to cause systemic and urinary alkalinization and under certain circumstances, metabolic alkalosis, but is not associated itself with any 'toxic' effects.We review the existing literature and debunk the perceived toxicity of citrate. We delve into the metabolism and clearance of citrate and question current data suggesting metabolic acidosis occurs as the result of citrate accumulation. SUMMARY: In conclusion, this article calls into question prevailing concerns about 'citrate toxicity'. We emphasize the need for a more nuanced understanding of its safety profile. We recommend discarding the term 'citrate toxicity' in favor of another frequently used, but more meaningful term: 'citrate accumulation'.

AKI treated with kidney replacement therapy in critically Ill allogeneic hematopoietic stem cell transplant recipients.

Acute kidney injury (AKI) is a frequent complication following allogeneic hematopoietic stem cell transplantation (allo-HSCT), but few studies have focused on AKI treated with kidney replacement therapy (AKI-KRT), particularly among critically ill patients. We investigated the incidence, risk factors, and 90-day mortality associated with AKI-KRT in 529 critically ill adult allo-HSCT recipients admitted to the ICU within 1-year post-transplant at two academic medical centers between 2011 and 2021. AKI-KRT occurred in 111 of the 529 patients (21.0%). Lower baseline eGFR, veno-occlusive disease, thrombotic microangiopathy, admission to an ICU within 90 days post-transplant, and receipt of invasive mechanical ventilation (IMV), total bilirubin ≥5.0 mg/dl, and arterial pH <7.40 on ICU admission were each associated with a higher risk of AKI-KRT. Of the 111 patients with AKI-KRT, 97 (87.4%) died within 90 days. Ninety-day mortality was 100% in each of the following subgroups: serum albumin ≤2.0 g/dl, total bilirubin ≥7.0 mg/dl, arterial pH ≤7.20, IMV with moderate-to-severe hypoxemia, and ≥3 vasopressors/inotropes at KRT initiation. AKI-KRT was associated with a 6.59-fold higher adjusted 90-day mortality in critically ill allo-HSCT vs. non-transplanted patients. Short-term mortality remains exceptionally high among critically ill allo-HSCT patients with AKI-KRT, highlighting the importance of multidisciplinary discussions prior to KRT initiation.

Predictions of Serum Phosphate Concentration during Continuous Renal Replacement Therapy Using a Steady-State Mass Balance Model.

INTRODUCTION: Hypophosphatemia is common during continuous renal replacement therapy (CRRT), but serum phosphate levels can potentially be maintained during treatment by either intravenous phosphate supplementation or addition of phosphate to renal replacement therapy (RRT) solutions. METHODS: We developed a steady-state phosphate mass balance model to assess the effects of CRRT dose on serum phosphate concentration when using both phosphate-free and phosphate-containing RRT solutions, with emphasis on low CRRT doses. RESULTS: The model predicted that measurements of serum phosphate concentration prior to (initial) and during CRRT (final) together with clinical data on CRRT dose, treatment duration, and phosphate supplementation can determine model patient parameters, that is, both the initial generation rate and clearance of phosphate prior to CRRT. Model parameters were then calculated from average patient data reported in several previous publications with a standard or high CRRT dose. Using representative model parameters for typical patients, predictions were then made of the effect of low CRRT dose on the change in serum phosphate levels after implementation of CRRT. The model predicted that CRRT at a low dose using phosphate-free RRT solutions will limit, but not eliminate, the incidence of hypophosphatemia. Further, the model predicted that CRRT at a low dose will have virtually no influence on the incidence of hyperphosphatemia when using phosphate-containing RRT solutions. CONCLUSIONS: This report identifies the clinical measurements to be used with the proposed model for individualizing the CRRT dose and RRT phosphate concentration to maintain serum phosphate concentrations in a desired range.

Acute kidney injury in patients with burns.

Burn injury is associated with a high risk of acute kidney injury (AKI) with a prevalence of AKI among patients with burns of 9-50%. Despite an improvement in burn injury survival in the past decade, AKI in patients with burns is associated with an extremely poor short-term and long-term prognosis, with a mortality of >80% among those with severe AKI. Factors that contribute to the development of AKI in patients with burns include haemodynamic alterations, burn-induced systemic inflammation and apoptosis, haemolysis, rhabdomyolysis, smoke inhalation injury, drug nephrotoxicity and sepsis. Early and late AKI after burn injury differ in their aetiologies and outcomes. Sepsis is the main driver of late AKI in patients with burns and late AKI has been associated with higher mortality than early AKI. Prevention of early AKI involves correction of hypovolaemia and avoidance of nephrotoxic drugs (for example, hydroxocobalamin), whereas prevention of late AKI involves prevention and early recognition of sepsis as well as avoidance of nephrotoxins. Treatment of AKI in patients with burns remains supportive, including prevention of fluid overload, treatment of electrolyte disturbance and use of kidney replacement therapy when indicated.

Anticoagulation practices for continuous renal replacement therapy: a survey of physicians from the United States.

BACKGROUND: During continuous renal replacement therapy (CRRT), anticoagulants are recommended for patients at low risk of bleeding and not already receiving systemic anticoagulants. Current anticoagulants used in CRRT in the US are systemic heparins or regional citrate. To better understand use of anticoagulants for CRRT in the US, we surveyed nephrologists and critical care medicine (CCM) specialists. METHODS: The survey contained 30 questions. Respondents were board certified and worked in intensive care units of academic medical centers or community hospitals. RESULTS: 150 physicians (70 nephrologists and 80 CCM) completed the survey. Mean number of CRRT machines in use increased ∼30% from the pre-pandemic era to 2022. Unfractionated heparin was the most used anticoagulant (43% of estimated patients) followed by citrate (28%). Respondents reported 29% of patients received no anticoagulant. Risk of hypocalcemia (52%) and citrate safety (42%) were the predominant reasons given for using no anticoagulant instead of citrate in heparin-intolerant patients. 84% said filter clogging was a problem when no anticoagulant was used, and almost 25% said increased transfusions were necessary. Respondents using heparin (n = 131) considered it inexpensive and easily obtainable, although of moderate safety, citing concerns of heparin-induced thrombocytopenia and bleeding. Anticoagulant citrate dextrose solution was the most used citrate. Respondents estimated that 37% of patients receiving citrate develop hypocalcemia and 17% citrate lock. CONCLUSIONS: Given the increased use of CRRT and the lack of approved, safe, and effective anticoagulant choices for CRRT in the US, effective use of current and other anticoagulant options needs to be evaluated.

Risk factors of hemodialysis catheter dysfunction in patients undergoing continuous renal replacement therapy: a retrospective study.

BACKGROUND: Continuous renal replacement therapy is a relatively common modality applied to critically ill patients with renal impairment. To maintain stable continuous renal replacement therapy, sufficient blood flow through the circuit is crucial, but catheter dysfunction reduces the blood flow by inadequate pressures within the circuit. Therefore, exploring and modifying the possible risk factors related to catheter dysfunction can help to provide continuous renal replacement therapy with minimal interruption. METHODS: Adult patients who received continuous renal replacement therapy at Seoul National University Hospital between January 2019 and December 2021 were retrospectively analyzed. Patients who received continuous renal replacement therapy via a temporary hemodialysis catheter, inserted at the bedside under ultrasound guidance within 12 h of continuous renal replacement therapy initiation were included. RESULTS: A total of 507 continuous renal replacement therapy sessions in 457 patients were analyzed. Dialysis catheter dysfunction occurred in 119 sessions (23.5%). Multivariate analysis showed that less prolonged prothrombin time (adjusted OR 0.49, 95% CI, 0.30-0.82, p = 0.007) and activated partial thromboplastin time (adjusted OR 1.01, 95% CI, 1.00-1.01, p = 0.049) were associated with increased risk of catheter dysfunction. Risk factors of re-catheterization included vascular access to the left jugular and femoral vein. CONCLUSIONS: In critically ill patients undergoing continuous renal replacement therapy, less prolonged prothrombin time was associated with earlier catheter dysfunction. Use of left internal jugular veins and femoral vein were associated with increased risk of re-catheterization compared to the right internal jugular vein.

Impact of Intensity of Continuous Renal Replacement Therapy on Duration of Ventilation in Critically Ill Patients: A Secondary Analysis of the RENAL Trial.

INTRODUCTION: More intensive renal replacement therapy (RRT) has been associated with prolonged mechanical ventilation (MV). However, such finding may be dependent on RRT modality. We hypothesized that, when using continuous renal replacement therapy (CRRT), RRT intensity would not be associated with prolonged MV. METHODS: In a secondary analysis of the Randomized Evaluation of Normal versus Augmented Level (RENAL) Replacement trial comparing different CRRT intensities, we applied Fine-Gray competing risk analysis with time to successful extubation within 28 days as primary outcome. RESULTS: We studied 531 patients in the higher intensity and 551 in the lower intensity group. Higher intensity patients had more hypophosphatemia (66.7 vs. 58.1%; p = 0.004) and more days with hypophosphatemia (2.2 ± 2.8 vs. 1.6 ± 2.2; p < 0.001). There was no difference in the number of patients extubated within 28 days (60.1% vs. 62.4%; adjusted subdistribution hazard ratio [SHR], 0.95 [95% CI, 0.86 to 1.06]) or time to extubation (8 [5-16] vs. 8 [5-15] days; adjusted median difference, 0.65 [95% CI, -0.41 to 1.70]). Among patients from the upper tertile of days with hypophosphatemia, higher intensity CRRT was associated with a lower chance of successful extubation within 28 days (SHR, 0.67 [95% CI, 0.55 to 0.82]; p for heterogeneity = 0.013). CONCLUSIONS: In the RENAL trial, higher intensity CRRT was not associated with delayed extubation. However, it was associated with a greater rate of hypophosphatemia and more days with hypophosphatemia was associated with a lower chance of successful extubation.

Peritoneal Dialysis during the COVID-19 Pandemic Is an Effective Treatment in Developing Countries: A Report from Mexico.

INTRODUCTION: During the height of the coronavirus disease-19 (COVID-19) pandemic, some renal replacement therapy (RRT) modalities were insufficient, forcing medical centers to diversify the RRT modalities offered. In this study, we reported the outcomes of chronic peritoneal dialysis (PD) patients and acute PD in critically ill patients during COVID-19 pandemic in a tertiary care medical center in Mexico. METHODS: This descriptive, longitudinal, observational, retrospective study included 47 adult patients with atypical pneumonia in a tertiary care medical center in Mexico during the first and second waves of the COVID-19 pandemic. Chronic PD patients and PD incident patients due to acute kidney injury (AKI) were included. RESULTS: Forty-seven patients were studied (29 chronic PD patients and 18 incident PD patients due to AKI); median age was 59 (48-68) years; 63.8% were men. The ultrafiltrate volume per day was 815 (596.1-1,193.2) mL. Overall mortality was 61.7%, 55.2% in chronic PD patients, and 72.2% in PD incident patients due to AKI. A higher Sequential Organ Failure Assessment (SOFA) score, the need for mechanical ventilation at admission, and the requirement for vasopressors were predictors for mortality (p < 0.01). CONCLUSION: In low- and lower-middle-income countries, PD was a valid alternative for RRT during the COVID-19 pandemic. In AKI patients, PD can correct hyperkalemia, acidosis, uremia, and volume overload; however, there was higher mortality in PD incident patients due to AKI. The main risk factors for mortality were a high SOFA score at admission, the need for invasive mechanical ventilation, and the requirement for vasopressors.

Long-term renal outcomes of patients with COVID-19: a meta-analysis of observational studies.

BACKGROUND: Kidney involvement is common in hospitalized coronavirus disease 2019 (COVID-19) patients during the acute phase, little is known about the long-term impact of COVID-19 on the kidney. METHODS: This is a systematic review and meta-analysis on long-term renal outcomes among COVID-19 patients. We carried out a systematic literature search in PUBMED, EMBASE, SCOPUS, and Cochrane COVID-19 study register and performed the random-effects meta-analysis of rates. The search was last updated on November 23, 2022. RESULTS: The study included 12 moderate to high-quality cohort studies involving 6976 patients with COVID-19-associated acute kidney injury and 5223 COVID-19 patients without acute kidney injury. The summarized long-term renal non-recovery rate, dialysis-dependent rate, and complete recovery rate among patients with COVID-19-associated AKI was 22% (12-33%), 6% (2-12%), and 63% (44-81%) during a follow-up of 90-326.5 days. Heterogeneity could be explained by differences in the prevalence of chronic kidney disease and proportion of acute kidney injury requiring renal replacement therapy using meta-regression; patients with more comorbidities or higher renal replacement therapy rate had higher non-recovery rates. The summarized long-term kidney function decrease rate among patients without acute kidney injury was 22% (3-51%) in 90-199 days, with heterogeneity partially explained by severity of infection. CONCLUSION: Patients with more comorbidities tend to have a higher renal non recovery rate after COVID-19-associated acute kidney injury; for COVID-19 patients without acute kidney injury, decrease in kidney function may occur during long-term follow-up. Regular evaluation of kidney function during the post-COVID-19 follow-up among high-risk patients may be necessary.

Improvement of composite kidney outcomes by AKI care bundles: a systematic review and meta-analysis.

INTRODUCTION: Various approaches have been suggested to identify acute kidney injury (AKI) early and to initiate kidney-protective measures in patients at risk or with AKI. The objective of this study was to evaluate whether care bundles improve kidney outcomes in these patients. METHODS: We conducted a systematic review of the literature to evaluate the clinical effectiveness of AKI care bundles with or without urinary biomarkers in the recognition and management of AKI. The main outcomes were major adverse kidney events (MAKEs) consisting of moderate-severe AKI, receipt of renal replacement therapy (RRT), and mortality. RESULTS: Out of 7434 abstracts screened, 946 published studies were identified. Thirteen studies [five randomized controlled trials (RCTs) and eight non-RCTs] including 16,540 patients were eligible for inclusion in the meta-analysis. Meta-analysis showed a lower incidence of MAKE in the AKI care bundle group [odds ratio (OR) 0.73, 95% confidence interval (CI) 0.66-0.81] with differences in all 3 individual outcomes [moderate-severe AKI (OR 0.65, 95% CI 0.51-0.82), RRT (OR 0.63, 95% CI = 0.46-0.88) and mortality]. Subgroup analysis of the RCTs, all adopted biomarker-based approach, decreased the risk of MAKE (OR 0.55, 95% CI 0.41-0.74). Network meta-analysis could reveal that the incorporation of biomarkers in care bundles carried a significantly lower risk of MAKE when compared to care bundles without biomarkers (OR = 0.693, 95% CI = 0.50-0.96), while the usual care subgroup had a significantly higher risk (OR = 1.29, 95% CI = 1.09-1.52). CONCLUSION: Our meta-analysis demonstrated that care bundles decreased the risk of MAKE, moderate-severe AKI and need for RRT in AKI patients. Moreover, the inclusion of biomarkers in care bundles had a greater impact than care bundles without biomarkers.

Proceedings of the 2022 UAB CRRT Academy: Non-Invasive Hemodynamic Monitoring to Guide Fluid Removal with CRRT and Proliferation of Extracorporeal Blood Purification Devices.

In 2022, we celebrated the 15th anniversary of the University of Alabama at Birmingham (UAB) Continuous Renal Replacement Therapy (CRRT) Academy, a 2-day conference attended yearly by an international audience of over 100 nephrology, critical care, and multidisciplinary trainees and practitioners. This year, we introduce the proceedings of the UAB CRRT Academy, a yearly review of select emerging topics in the field of critical care nephrology that feature prominently in the conference. First, we review the rapidly evolving field of non-invasive hemodynamic monitoring and its potential to guide fluid removal by renal replacement therapy (RRT). We begin by summarizing the accumulating data associating fluid overload with harm in critical illness and the potential for harm from end-organ hypoperfusion caused by excessive fluid removal with RRT, underscoring the importance of accurate, dynamic assessment of volume status. We describe four applications of point-of-care ultrasound used to identify patients in need of urgent fluid removal or likely to tolerate fluid removal: lung ultrasound, inferior vena cava ultrasound, venous excess ultrasonography, and Doppler of the left ventricular outflow track to estimate stroke volume. We briefly introduce other minimally invasive hemodynamic monitoring technologies before concluding that additional prospective data are urgently needed to adapt these technologies to the specific task of fluid removal by RRT and to learn how best to integrate them into practical fluid-management strategies. Second, we focus on the growth of novel extracorporeal blood purification devices, starting with brief reviews of the inflammatory underpinnings of multiorgan dysfunction and the specific applications of pathogen, endotoxin, and/or cytokine removal and immunomodulation. Finally, we review a series of specific adsorptive technologies, several of which have seen substantial clinical use during the COVID-19 pandemic, describing their mechanisms of target removal, the limited existing data supporting their efficacy, ongoing and future studies, and the need for additional prospective trials.

Different Roles of Functional and Structural Renal Markers Measured at Discontinuation of Renal Replacement Therapy for Acute Kidney Injury.

INTRODUCTION: Severe acute kidney injury (AKI) requiring renal replacement therapy (RRT) has been associated with an unacceptably high mortality of 50% or more. Successful discontinuation of RRT is thought to be linked to better outcomes. Although functional and structural renal markers have been evaluated in AKI, little is known about their roles in predicting outcomes at the time of RRT discontinuation. METHODS: In this prospective single-center cohort study, we analyzed patients who received continuous RRT (CRRT) for AKI between August 2016 and March 2018 in the intensive care unit of the University of Tokyo Hospital (Tokyo, Japan). Clinical parameters and urine samples were obtained at CRRT discontinuation. Successful CRRT discontinuation was defined as neither resuming CRRT for 48 h nor receiving intermittent hemodialysis for 7 days from the CRRT termination. Major adverse kidney events (MAKEs) were defined as death, requirement for dialysis, or a decrease in the estimated glomerular filtration rate (eGFR) of more than 25% from the baseline at day 90. RESULTS: Of 73 patients, who received CRRT for AKI, 59 successfully discontinued CRRT and 14 could not. Kinetic eGFR, urine volume, urinary neutrophil gelatinase-associated lipocalin (NGAL), and urinary L-type fatty acid binding protein were predictive for CRRT discontinuation. Of these factors, urine volume had the highest area under the curve (AUC) 0.91 with 95% confidence interval [0.80-0.96] for successful CRRT discontinuation. For predicting MAKEs at day 90, the urinary NGAL showed the highest AUC 0.76 [0.62-0.86], whereas kinetic eGFR and urine volume failed to show statistical significance (AUC 0.49 [0.35-0.63] and AUC 0.59 [0.44-0.73], respectively). CONCLUSIONS: Our prospective study confirmed that urine volume, a functional renal marker, predicted successful discontinuation of RRT and that urinary NGAL, a structural renal marker, predicted long-term renal outcomes. These observations suggest that the functional and structural renal makers play different roles in predicting the outcomes of severe AKI requiring RRT.

Early strategy vs. late initiation of renal replacement therapy in adult patients with acute kidney injury: an updated systematic review and meta-analysis of randomized controlled trials.

OBJECTIVE: The optimal time to start renal replacement therapy (RRT) for acute kidney injury (AKI) remains controversial. We aim to compare the effects of early vs. delayed RRT initiation on clinical outcomes in adult patients with AKI. MATERIALS AND METHODS: PubMed, Embase, Cochrane Library, Web of Science, Chinese Biomedical Literature Database, ClinicalTrials.gov, and the International Clinical Trial registry platform were systematically searched from inception to 7 August 2022. The review included randomized clinical trials (RCTs) comparing early and delayed initiation of RRT in AKI patients. The selected primary outcomes were short-term and long-term mortality. Secondary outcomes included RRT dependency, intensive care unit (ICU) length of stay, hospital length of stay, mechanical ventilator-free days, vasoactive agents-free days, RRT-free days, and adverse events. RESULTS: Overall, 15 RCTs, including 5,625 patients, were analyzed. Early RRT showed no survival benefit when compared to the delayed therapy (28-or 30-day mortality: RR, 1.01, 95% CI: 0.94-1.08, p = 0.87; 60-day mortality: RR, 0.87, 95% CI: 0.71-1.06, p = 0.16; 90-day mortality: RR, 1.00, 95% CI: 0.88-1.13, p = 0.97; in-hospital mortality: RR, 1.05, 95% CI: 0.88-1.24, p = 0.58; ICU mortality: RR, 1.00, 95% CI: 0.91-1.10, p = 0.98). The delayed RRT did not lead to a higher risk of RRT dependency, ICU, or hospital length of stay than the early RRT. Similarly, early initiation of RRT did not lead to longer ventilator-free, vasoactive agent-free, and RRT-free days. However, early RRT initiation was associated with more adverse events. CONCLUSIONS: Our study suggested that early RRT initiation was not associated with survival benefits or better clinical outcomes and increased the risk of RRT-associated adverse events. Current evidence does not support the use of early RRT for AKI patients without urgent indications.