Augmented Renal Clearance in COVID-19

Impact of augmented renal clearance on anticoagulant therapy in critically ill patients with coronavirus disease 2019: A retrospective cohort study

INTRODUCTION

This study aimed to determine the impact of augmented renal clearance (ARC) on anticoagulation therapy in critically ill patients with coronavirus disease 2019 (COVID-19).

METHODS

This retrospective cohort study included adult patients with severe COVID-19 with ARC who had been treated at our hospital between 2020 and 2021. We measured the estimated glomerular filtration rate calculated by the Chronic Kidney Disease Epidemiology Collaboration formula (eGFRCKD-EPI) every morning, and ARC condition was defined as eGFRCKD-EPI ≥ 130 mL/min/1.73 m2. Multivariate regression analysis with Huber-White sandwich estimator was performed to examine the association of unfractionated heparin (UH) dosage between blood test timings with activated partial thromboplastin time (APTT) compared with and without ARC.

RESULTS

We identified 38 enrolled patients: seven and 31 in the ARC and non-ARC groups, respectively. In the ARC coexisting condition, a higher dose of UH, which corresponded to the total dose in 24 h from the previous day, was required to achieve the same APTT prolongation, with a significant difference (p < 0.001).

CONCLUSIONS

Our study suggests that careful monitoring and consideration of higher UH doses in critically ill patients with COVID-19 is necessary because anticoagulation failure can occur during ARC.

Treatment implications of augmented renal clearance in a critically ill COVID-19 patient: A case report

Augmented renal clearance (ARC) is a pathophysiological phenomenon that can occur in critically ill patients, leading to enhanced renal function. It is defined as a creatinine clearance of >130 mL/min/1.73 m2 . ARC can lead to subtherapeutic levels of renally cleared drugs and subsequent treatment failure. In COVID-19, it has only been described in the literature in a few cases. We present the case of a 38-year-old critically ill patient with COVID-19 who developed ARC with an initial clearance of 226 mL/min/1.73 m2 , persisting for 30 days. He required high doses of sedatives and neuromuscular blocking agents, as well as increased doses of vancomycin and dalteparin, to reach adequate serum levels. This case emphasizes the importance for clinicians to consider ARC in the dosing of all renally cleared drugs, including antibiotics, low molecular weight heparins, and sedatives, to prevent subtherapeutic drug levels and treatment failure.

External Validation of the Augmented Renal Clearance Predictor in Critically Ill COVID-19 Patients

The ARC predictor is a prediction model for augmented renal clearance (ARC) on the next intensive care unit (ICU) day that showed good performance in a general ICU setting. In this study, we performed a retrospective external validation of the ARC predictor in critically ill coronavirus disease 19 (COVID-19) patients admitted to the ICU of the University Hospitals Leuven from February 2020 to January 2021. All patient-days that had serum creatinine levels available and measured creatinine clearance on the next ICU day were enrolled. The performance of the ARC predictor was evaluated using discrimination, calibration, and decision curves. A total of 120 patients (1064 patient-days) were included, and ARC was found in 57 (47.5%) patients, corresponding to 246 (23.1%) patient-days. The ARC predictor demonstrated good discrimination and calibration (AUROC of 0.86, calibration slope of 1.18, and calibration-in-the-large of 0.14) and a wide clinical-usefulness range. At the default classification threshold of 20% in the original study, the sensitivity and specificity were 72% and 81%, respectively. The ARC predictor is able to accurately predict ARC in critically ill COVID-19 patients. These results support the potential of the ARC predictor to optimize renally cleared drug dosages in this specific ICU population. Investigation of dosing regimen improvement was not included in this study and remains a challenge for future studies.

Remdesivir Administration in COVID-19 Patients With Renal Impairment: A Systematic Review

BACKGROUND

Remdesivir (RDV) is the main antiviral for the treatment of moderate to severe forms of Coronavirus disease 2019 (COVID-19). Several studies revealed a shortening time to clinical improvement of COVID-19 and mortality benefits in patients receiving RDV. The patients with renal disease were excluded from large clinical trials of RDV, and the probable nephrotoxicity of the drug, its metabolites, and the vehicle (sulfobutylether-β-cyclodextrin) have led to the recommendation against using RDV in patients with an estimated glomerular filtration rate of <30 mL/min.

AREAS OF UNCERTAINTY

This systematic review aimed to collect data about the necessity and safety administration of RDV in the setting of renal impairment.

DATA SOURCES

Search through databases including MEDLINE, ScienceDirect, Cochrane Library, and PubMed was performed. The studies were carried out in adults and enrolled patients with different types of renal impairment (ie, acute kidney injury, chronic kidney disease, kidney transplant, and renal replacement therapy) were included. Eligible studies were assessed, and required data were extracted.

RESULTS

Twenty-two cross-sectional studies, cohorts, case reports, and case series were included in this review. The mortality rate was between 7.3% and 50%, and various severity of COVID-19 was included in the studies. None of them reported an increase in adverse effects attributed to RDV administration. A decrease in inflammatory mediators and other benefits were obvious.

CONCLUSIONS

Although the manufacturer's labeling does not recommend RDV administration in patients with severe renal impairment, it seems that nephrotoxicity is less concerning in the population of these patients. Moreover, RDV may be helpful in acute kidney injury induced by the viral invasion of COVID-19. To the best of our knowledge, this is the first systematic review of the use of RDV in kidney failure. Larger, well-designed, and pharmacokinetic studies are required to have a safe and logical recommendation about the use of RDV in patients with renal disorders.

Validation of the Augmented Renal Clearance in Trauma Intensive Care scoring system for augmented renal clearance prediction in a trauma subgroup of a mixed ICU population

WHAT IS KNOWN AND OBJECTIVE

Augmented renal clearance is prevalent in trauma patients and leads to subtherapeutic levels of renally eliminated medications with potentially unfavourable clinical outcomes. The Augmented Renal Clearance of Trauma in Intensive Care (ARCTIC) score has been developed to predict augmented renal clearance in critically ill trauma patients. Our primary objective was to validate this score among the trauma subgroup of a mixed intensive care patient cohort.

METHODS

This single-centre, retrospective, observational cohort study assessed augmented renal clearance using a timed 24-h urine collection performed weekly. ARC was defined as a measured creatinine clearance of ≥130 ml/min/1.73 m² . ARCTIC score performance was evaluated through a receiver operator characteristic curves and analysis of sensitivities and specificities for the trauma subgroup, the medical/surgical subgroup and the pooled cohort.

RESULTS AND DISCUSSION

Augmented renal clearance was observed in 33.9% (n = 58) of trauma patients (n = 171) and 15.7% (n = 24) of medical/surgical patients (n = 153). Examination of different cutoffs for the ARCTIC score in our trauma population confirmed that the optimal cutoff score was ≥6. Comparison between ROC curves for ARCTIC score and for regression model based upon our data in trauma patients indicated validation of the score in this subgroup. Comparison of sensitivities and specificities for ARCTIC score between trauma (93.1% and 41.6%, respectively) and medical/surgical subjects (87.5% and 49.6%, respectively) showed no clinical nor statistical difference, suggesting validation for the medical/surgical subgroup as well.

WHAT IS NEW AND CONCLUSION

In our mixed ICU population, the ARCTIC score was validated in the trauma subgroup. We also found that the score performed well in the medical/surgical population. Future studies should assess the performance of the ARCTIC score prospectively.

Pharmacokinetic characterization of favipiravir in patients with COVID-19

This prospective observational study describes the pharmacokinetic characteristics of favipiravir in adult patients hospitalized for mild to moderate COVID-19 with a positive RT-PCR test. Favipiravir was administered for 5 days, with a loading dose of 3200 mg and a maintenance dose of 1200 mg/day. Serial blood samples were collected on Day-2 and Day-4 of the therapy. Laboratory findings of the patients (n=21) and in-hospital mortality were recorded. Favipiravir concentrations exhibited substantial variability and a significant decrease during the treatment of COVID-19. The median favipiravir trough concentration (C_0-trough ) on Day-2 was 21.26 (IQR, 8.37-30.78) μg/mL whereas it decreased significantly to 1.61 (IQR, 0.00-6.41) μg/mL on Day-4, the area under the concentration versus time curve decreased by 68.5%. Day-2-C_0-trough of female patients was higher than male patients. Our findings indicate that favipiravir concentrations show significant variability during the treatment of COVID-19 and therapeutic drug monitoring may be necessary to maintain targeted concentrations.