Use of the RenalGuard system to prevent contrast-induced AKI: A meta-analysis

Effect of periprocedural furosemide-induced diuresis with matched isotonic intravenous hydration in patients with chronic kidney disease undergoing transcatheter aortic valve implantation

BACKGROUND

Acute kidney injury (AKI) after transcatheter aortic valve implantation (TAVI) is a serious complication which is associated with increased mortality. The RenalGuard system was developed to reduce the risk of AKI after contrast media exposition by furosemide-induced diuresis with matched isotonic intravenous hydration. The aim of this study was to examine the effect of the RenalGuard system on the occurrence of AKI after TAVI in patients with chronic kidney disease.

METHODS

The present study is a single-center randomized trial including patients with severe aortic valve stenosis undergoing TAVI. Overall, a total of 100 patients treated by TAVI between January 2017 and August 2018 were randomly assigned to a periprocedural treatment with the RenalGuard system or standard treatment by pre- and postprocedural intravenous hydration. Primary endpoint was the occurrence of AKI after TAVI, and secondary endpoints were assessed according to valve academic research consortium 2 criteria.

RESULTS

Overall, the prevalence of AKI was 18.4% (n = 18). The majority of these patients developed mild AKI according to stage 1. Comparing RenalGuard to standard therapy, no significant differences were observed in the occurrence of AKI (RenalGuard: 21.3%; control group: 15.7%; p = 0.651). In addition, there were no differences between the groups with regard to 30-day and 12-month mortality and procedure-associated complication rates.

CONCLUSION

In this randomized trial, we did not detect a reduction in AKI after TAVI by using the RenalGuard system. A substantial number of patients with chronic kidney disease developed AKI after TAVI, whereas the majority presented with mild AKI according to stage 1 (ClinicalTrials.gov number NCT04537325).

Outcomes of lower extremity peripheral arterial interventions in patients with and without chronic kidney disease or end-stage renal disease

INTRODUCTION

Peripheral arterial disease (PAD) is a progressive vascular condition characterized by the narrowing or blockage of arteries, primarily attributed to atherosclerosis. PAD's prevalence in the general population is estimated at approximately 5.9%. Notably however, among patients with chronic kidney disease (CKD), PAD's prevalence is substantially higher, ranging from 17% to 48%. This review paper emphasizes the pervasiveness of PAD and its intricate relationship with CKD and end-stage renal disease (ESRD). It demonstrates the importance of early detection, proactive screening, and understanding the formidable challenges associated with treating heavily calcified lesions.

EVIDENCE ACQUISITION

Comprehensive literature searches encompassed the PubMed/MEDLINE, Cochrane Library, and Embase databases, in order to identify studies involving lower extremity peripheral arterial interventions in patients both with and without CKD or ESRD. The search spanned the timeframe from January 2001 to July 2023. The search strategy included vocabulary terms concerning peripheral artery disease, lower extremities, revascularization, chronic kidney disease, and end-stage renal disease.

EVIDENCE SYNTHESIS

Initial searches were used to identify articles based on title. Exclusion criteria was then applied, and any redundant articles were removed. The articles abstracts were then reviewed, and relevant articles were selected. Once selected the articles were thoroughly reviewed including the references to find other relevant articles that were missed during the initial search process. In total 28 articles were selected and included for review of clinical data in regard to PAD outcomes in patients with advanced kidney disease.

CONCLUSIONS

The findings highlight the need for personalized approaches in diagnosing and treating PAD in CKD and ESRD patients. Interdisciplinary collaboration, such as those between nephrologists, vascular surgeons, and interventional radiologists, is vital to optimize outcomes. Further research should focus on innovative, tailored interventions to enhance limb preservation, reduce mortality, prolong patency, and cut healthcare costs.

Risk of Acute Kidney Injury Following IV Iodinated Contrast Media Exposure: 2023 Update, From the AJR Special Series on Contrast Media

Iodinated contrast material (ICM) has revolutionized the field of diagnostic radiology through improvements in diagnostic performance and expansion in clinical indications for radiographic and CT examinations. Historically, nephrotoxicity was a feared complication of ICM use, thought to be associated with a significant risk of morbidity and mortality. Such fears often precluded use of ICM in imaging evaluations, commonly at the expense of diagnostic performance and timely diagnosis. Over the past 20 years, the nephrotoxic risk of ICM has become a topic of debate, as more recent evidence from higher-quality studies now suggest that many cases of what was considered contrast-induced acute kidney injury (CI-AKI) were likely cases of mistaken causal attribution; most of these cases represented either acute kidney injury (AKI) caused by any of myriad other known factors that can adversely affect renal function and were coincidentally present at the time of contrast media exposure (contrast-associated AKI (CA-AKI)) or a manifestation of the normal variation in renal function that increases with worsening renal function. This review discusses the current state of knowledge on CI-AKI and CA-AKI including the incidence, risk factors, outcomes, and prophylactic strategies in the identification and management of these clinical conditions.

Diuresis-matched versus standard hydration in patients undergoing percutaneous cardiovascular procedures: meta-analysis of randomized clinical trials

INTRODUCTION AND OBJECTIVES

Contrast-associated acute kidney injury (CA-AKI) is a potential complication of procedures requiring administration of iodinated contrast medium. RenalGuard, which provides real-time matching of intravenous hydration with furosemide-induced diuresis, is an alternative to standard periprocedural hydration strategies. The evidence on RenalGuard in patients undergoing percutaneous cardiovascular procedures is sparse. We used a Bayesian framework to perform a meta-analysis of RenalGuard as a CA-AKI preventive strategy.

METHODS

We searched Medline, Cochrane Library and Web of Science for randomized trials of RenalGuard vs standard periprocedural hydration strategies. The primary outcome was CA-AKI. Secondary outcomes were all-cause death, cardiogenic shock, acute pulmonary edema, and renal failure requiring renal replacement therapy. A Bayesian random-effect risk ratio (RR) with corresponding 95% credibility interval (95%CrI) was calculated for each outcome. PROSPERO database number CRD42022378489.

RESULTS

Six studies were included. RenalGuard was associated with a significant relative reduction in CA-AKI (median RR, 0.54; 95%CrI, 0.31-0.86) and acute pulmonary edema (median RR, 0.35; 95%CrI, 0.12-0.87). No significant differences were observed for the other secondary endpoints [all-cause death (RR, 0.49; 95%CrI, 0.13-1.08), cardiogenic shock (RR, 0.06; 95%CrI, 0.00-1.91), and renal replacement therapy (RR, 0.52; 95%CrI, 0.18-1.18)]. The Bayesian analysis also showed that RenalGuard had a high probability of ranking first for all the secondary outcomes. These results were consistent in multiple sensitivity analyses.

CONCLUSIONS

In patients undergoing percutaneous cardiovascular procedures, RenalGuard was associated with a reduced risk of CA-AKI and acute pulmonary edema compared with standard periprocedural hydration strategies.

Radiographic Contrast Media and the Kidney

AKI is a potential complication of intravascular iodinated contrast exposure. Contrast-associated AKI, which typically manifests as small and transient decrements in kidney function that develop within several days of contrast administration, is associated with serious adverse outcomes, including progressive kidney dysfunction and death. However, a causal link between the small increases in serum creatinine that characteristically occur with contrast-associated AKI and serious adverse outcomes remains unproven. This is important given mounting evidence that clinically indicated, potentially lifesaving radiographic procedures are underutilized in patients with CKD. This has been hypothesized to be related to provider concern about precipitating contrast-associated AKI. Intravascular gadolinium-based contrast, an alternative to iodinated contrast that is administered with magnetic resonance imaging, has also been linked with potential serious adverse events, notably the development of nephrogenic systemic fibrosis in patients with severe impairment in kidney function. Patients hospitalized in the intensive care unit frequently have clinical indications for diagnostic and therapeutic procedures that involve the intravascular administration of contrast media. Accordingly, critical care providers and others treating critically ill patients should possess a sound understanding of the risk factors for and incidence of such outcomes, the ability to perform evidence-based risk-benefit assessments regarding intravascular contrast administration, and knowledge of empirical data on the prevention of these iatrogenic complications.

Contrast Induced Nephropathy: Efficacy of matched hydration and forced diuresis for prevention in patients with impaired renal function undergoing coronary procedures–CINEMA trial

Background

Matched hydration and forced diuresis (MHFD) using the RenalGuard device has been shown to reduce contrast induced nephropathy (CIN) following coronary interventions.

Aim

To evaluate the potential benefits of a non-automated MHFD protocol compared to current hydration protocol in prevention of CIN in patients with CKD.

Methods

A total of 1,205 patients were randomized to either non-automated MHFD group (n = 799) or intravenous hydration control group (n = 406). The MHFD group received 250 ml IV normal saline over 30 min before the coronary procedure followed by 0.5 mg/kg IV furosemide. Hydration infusion rate was manually adjusted to replace the patient's urine output. When urine output rate reached > 300 ml/h, patients underwent coronary procedure. Matched fluid replacement was maintained during the procedure and for 4-hour post-treatment. CIN was defined conventionally as ≥ 25% or ≥ 0.5 mg/dl rise in serum creatinine over baseline.

Results

CIN occurred in 121 of 1,205 (10.0%) patients in our study. With respect to the primary outcome, 64 (8.01%) of the MHFD patients developed CIN compared with 57 (14.04%) of the control group (p < 0.001).

Conclusions

A non-automated MHFD protocol is an effective and safe method for the prevention of CIN in patients with CKD.

[Effect of half-dose fluorescein sodium contrast agent on liver and kidney functions in patients with mild to moderate chronic kidney disease: a retrospective cohort study]

OBJECTIVE

To observe the effect of half-dose fluorescein sodium (FINa) contrast agent on liver and kidney functions in patients with mild to moderate (stage 1 to 3) chronic kidney disease (CKD) and the incidence of contrast-induced nephropathy (CIN).

METHODS

Seventy-seven patients (including 50 male and 27 female patients with an mean age of 53.5±9.6 years) with CKD with normal renal function or mild to moderate abnormalities underwent fundus fluorescein angiography (FFG) examination with half-dose FINa. Liver function, blood creatinine (Scr), blood urea nitrogen (BUN), urine β2 microglobulin (β2-MG), and glomerular filtration rate (eGFR) of the patients were measured within 3 days before intravenous injection of the contrast agent and at 1, 3, 7, and 30±1 days after the operation to analyze the effect of the contrast agent on renal function.

RESULTS

Among the 77 patients, CIN occurred only in one case with an incidence rate of 1.30%. BUN, urine β2- MG, or rapid microalbumin/creatinine did not vary significantly after FFA in these patients. Scr levels showed no significant increments at 1 day and 7 days after FFA, but increased significantly at 3 days (24.6±2.3; P < 0.01) and 30 days (16.0±21.7; P < 0.05). Urine NAG enzymes and urinary osmolality were significantly reduced at 1, 3, 7, and 30 days after FFA (P < 0.01). The eGFR decreased significantly to 10.23±0.62 at 3 days after FAG and became normal at 7 days. Urine albumin level decreased significantly at 1, 3, 7, and 30 days after FFA (P < 0.01). Blood β2-MGFAG level increased significantly at 3 days after FFA (0.314± 0.121; P < 0.01), but decreased to 0.134±0.143 at 7 days (P < 0.05). The level transaminase decreased significantly at 3 and 7 days after FFA (P < 0.01).

CONCLUSION

Half-dose of FINa has no significant effect on liver function and has only minimal effect on kidney function in patients with mild to moderate CKD, and FFA with half-dose FINa can therefore be safely performed in these patients.

Implications of Renal Disease in Patients Undergoing Peripheral Arterial Interventions

Since the first peripheral endovascular intervention (PVI) in 1964, the procedure's technical aspects and indications have advanced significantly. Today, endovascular procedures span the spectrum of presentations from acute limb ischemia to critical limb ischemia and symptomatic limiting claudication. Goals of PVI remain restoring limb perfusion, minimizing rates of amputation and mortality, and sparing the need for the high-risk bypass surgery. Unfortunately, there are no large randomized controlled trials that address the optimal approach to peripheral arterial disease revascularization in chronic kidney disease (CKD) patients.

Controlled decongestion by Reprieve therapy in acute heart failure: results of the TARGET-1 and TARGET-2 studies

AIMS

Safe and effective decongestion is the main goal of therapy in acute heart failure (AHF). In the non-randomized, prospective TARGET-1 and TARGET-2 studies (NCT03897842), we investigated whether adding the Reprieve System® (which continuously monitors urine output and delivers a matched volume of hydration fluid sufficient to maintain the set fluid balance rate) to standard diuretic-based regimen improves decongestion in AHF.

METHODS AND RESULTS

The population consisted of 19 patients hospitalized with AHF (mean age 67 ± 10 years, 18 male, ejection fraction 34 ± 15%, median N-terminal pro-B-type natriuretic peptide 4492 pg/mL). Patients served as their own controls: each patient underwent 24 h of standard diuretic therapy followed by 24 h of diuretics with Reprieve therapy (with normal saline used for matched volume replacement). The primary efficacy endpoint of actual fluid loss not exceeding the target fluid loss at the end of therapy was met in all 19 (100%) patients. The mean diuresis during Reprieve therapy was 6284 ± 2679 mL (vs. 1966 ± 1057 mL 24 h before therapy) and 2053 ± 888 mL (24 h after therapy) (both P < 0.0001). At the end of therapy, patient global assessment improved from 7.7 ± 1.1 to 3.0 ± 1.3 points (P < 0.001), central venous pressure decreased from 15.5 ± 5.3 mmHg to 12.8 ± 4.8 mmHg (P < 0.05) and the median urine sodium loss was 9.7 [3-13] mmol/h. The Reprieve therapy was safe, systolic blood pressure remained stable, mean creatinine dropped from 1.45 ± 0.4 mg/dL to 1.26 ± 0.4 mg/dL (P < 0.001) and biomarkers of renal injury did not change during treatment.

CONCLUSIONS

The Reprieve System in conjunction with diuretic therapy supports safe and controlled decongestion in AHF.

[Management of renal failure in old patients undergoing percutaneous cardiac interventions]

The elderly benefit from the advances of the interventional cardiology, especially for coronary artery disease and aortic valve stenosis. The prevalence of comorbidities is high in old population, but the benefit-risk balance remains often positive. Chronic kidney disease is frequent and amplifies the risks of contrast-induced nephropathy and acute kidney injury with an impact on clinical course and outcomes, and additional costs. Preventive strategies recognized as efficient to limit renal adverse events must be applied. Future approach may involve research in vulnerable old patients undergoing cardiac interventions.