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ISSN: 2472-1220
Journal of Kidney

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The Renal Guard System for the Prevention of Contrast-Induced Acute Kidney Injury

Cristina Quintavalle1, Chiara Sordelli2, Giovanni Napolitano3, Gerolama Condorelli1 and Carlo Briguori2*

1Department of Molecular Medicine and Medical Biotechnologies, "Federico II” University of Naples, and IEOS, CNR Naples, Italy

2Interventional Cardiology and Department of Cardiology, Clinica Mediterranea, Naples, Italy

3University of Cardiology, Hospital San Giuliano, Naples, Italy

*Corresponding Author:
Carlo Briguori MD, PhD
Interventional Cardiology
Clinica Mediterranea
Via Orazio 2, Naples
I-80121, Italy
Tel: 39081/7259764
Fax: 39081/7259777
E-mail: [email protected]

Received date: May 17, 2016; Accepted date: May 26, 2016; Published date: June 2, 2016

Citation: Quintavalle C, Sordelli C, Napolitano G, Condorelli G, Briguori C (2016) The Renal Guard System for the Prevention of Contrast-Induced Acute Kidney Injury. J Kidney 2:128. doi:10.4172/2472-1220.1000128

Copyright: © 2016 Quintavalle C, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

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Contrast-induced acute kidney injury (CI-AKI) accounts for approximately 10% of all causes of hospital-acquired renal failure, causes a prolonged in-hospital stay and represents a strong predictor of poor early and late outcome. A general consensus exists on the beneficial prophylactic effect of hydration The Renal Guard system (PLC Medical System, Inc. Franklin, MA, USA) has been developed to facilitate optimal hydration therapy. This device allows to achieve high urine flow rate (≥ 300 ml/h) while simultaneously balancing urine output and venous fluid infusion to prevent hypovolemia. Some studies have shown that the Renal Guard system is more effective than the conventional hydration regimen in preventing CI-AKI. A recent study suggests that the best threshold for CI-AKI prevention is a mean intraprocedural urine flow rate ≥ 450 ml/h.


Iodinated contrast media; Nephrotoxicity; Prevention; Antioxidant


In the last decades percutaneous coronary, peripheral and valvular procedures have substantially increased. The administration of iodinated contrast media (CM) is essential for all these procedures. Although usually well tolerated; CM may induce acute kidney injury (AKI). CM-induced AKI (CI-AKI) has become the third cause for hospital-acquired renal failure with a prolongation of the hospital stay and consequently an increase of health costs1. Beyond that, patients developing CI-AKI are at higher risk of both a further deterioration of kidney function and an unfavorable clinical outcome [1]. The most common clinical definitions of CI-AKI are based on the increase in serum creatininelevels ≥ 25% and ≥ 0.5 mg/dl from the baseline value at 48 hours after CM administration or the need for dialysis [2]. Different strategies have been proposed to prevent this complication [3]. In this review we discuss on the potential advantages of the Renal Guard system to prevent CI-AKI.

The Renal Guard® System

A general consensus exists on the beneficial effect of hydration in preventing CI-AKI [3]. Hydration induces an increase of urine flow rate (UFR), reduces the concentration of CM in the tubule and expedites CM excretion thus reducing the exposure time of tubular cells to the toxic effects of CM [4-6]. The most recommended hydration regimen is normal saline infusion at 1 ml/kg/h 12 hours before and 12 hours after CM exposure [3]. Limitations of this hydration regimen include 1) preclusion in urgent/emergent settings, and 2) suboptimal efficacy in high risk patients.

One approach for CI-AKI prophylaxis implies the induction and maintenance of a high UFR. The Prevention of Radiocontrast Induced Nephropathy Clinical Evaluation (PRINCE) study indicates that increasing the UFR to ≥ 150 ml/h reduces the toxic effect of CM [7]. However, this UFR was reached in <30% of patients. In particular, in patients treated with ipotonic infusion alone UFR was 122 ± 54 ml, whereas in those treated with ipotonic infusion plus furosemide, dopamineand mannitol UFR was 167 ± 58 ml [7]. The high UFR should be reached by maintaining a constant intravascular volume in order to prevent hypovolemia [7].

Theoretically, furosemide should protect the kidney by reducing the outer medullary hypoxia caused by CM by blocking the Na-K-2Cl transporter in the medullary thick ascending limb [8]. However, compelling data support that neither mannitol nor furosemide offer additional protection against (but may actually exacerbate) CI-AKI as compared with saline hydration alone [9,10]. Significant weight losswas observed in the patients treated with furosemide, suggesting that the potentially deleterious effect of furosemide was the result of a negative fluid balance.

The Renal Guard system (PLC Medical System, Inc. Franklin, MA, USA) has been developed to facilitate optimal hydration therapy. This device allows to achieve high urine output while simultaneously balancing urine output and venous fluid infusion to prevent hypovolemia[11]. The Renal Guard system includes a) a closed loop fluid management system; b) a high volume fluid pump, c) a high accuracy dual weight measuring system; d) motion detection artifact reduction; e) a single use intravenous set and urine collection system that interfaces with a standard Foley catheter; f) real-time display of urine and replacement fluid volume; g) a timely alerts to drain the urine bag or to replace the hydration fluid bag; f) and safety features such as automatic air and occlusiondetection [11] (Figure 1).


Figure 1: The Renal Guard system.

Some studies have shown that the approach of controlled, forced diuresis using the Renal Guard therapy is more effective than the conventional therapy in preventing CI-AKI in patients undergoing percutaneous coronary interventions [12-14] or transcatheter aortic valve implantation [15,16]. An initial bolus (priming) of 250 ml is infused over 30 minutes.

Following the priming, furosemide (0.25 mg/kg) is administered intravenously in order to achieve high (≥ 300 ml/h) UFR. Controlled hydration by the Renal Guard system continued during the procedure and for 4 hours following the procedure. Urine flow should be monitored and maintained at the target value throughout the procedure and during the following 4 hours (Figure 2).


Figure 2: Diagram showing each stage of the Renal Guard therapy. The dotter-green line represents the suggested mean urine flow rate cutoff of 300 ml/h. The dotter-orange line represents the suggested intraprocedural urine flow rate cutoff of 450 ml/h.

Additional furosemide doses are allowed in instances where there is a decrease in UFR below the target value. Briguori, et al. [12] reported a 53% relative risk reduction CI-AKI rate in patients treated by the Renal Guard system compared to the standard therapy. The beneficial effect was also documented by a lower severity of kidney damage, a lower rate of in-hospital dialysis and a smaller increase in serumcystatin C in the Renal Guard group than in the Control group. In the same way, Marenzi, et al. observed a 60% reduction in the incidence of CI-AKI in elective angiographypatients who were treated with Renal Guard system [13].

Concerns have been raised for the high UFR obtained with the Renal Guard system due to the potential hazards of impairment in electrolyte balance and the risk of acute pulmonary edema. However, no significant changes in electrolyte balance were documented and the highly accurate, temporally matched fluid replacement observed reduced the risk of hypovolemia. Furthermore, the rate of pulmonary edema was very low [12].

In order to clarify the relationship between UFR and CI-AKI, we conducted a study assessing what should be the ideal UFR for an optimal CI-AKI prevention. We observed that the best threshold for CI-AKI prevention is a mean intraprocedural UFR ≥ 450 ml/h [17]. In high risk patients, this intraprocedural UFR target (≥ 450 ml/h) was reached in less than 50% of patients, and in 92% of those patients who did not developed CI-AKI, whereas an UFR ≤ 450 ml/h was observed in 68% of patients who developed CI-AKI.

On the contrary, the proposed UFR threshold ≥ 300 ml/h showed lower performance. In high risk patients, this proposed UFR target (≥ 300 ml/h) was reached in the 91.5% of patients, whereas in the remaining 8.5% patients it was constantly below the target. This cutoff has been adopted from the PRINCE study, which suggests that increasing the UFR ≥ 150 ml/h reduces the toxic effect of CM, but was never directly confirmed in the clinical practice [7]. The observed prevalent importance of the mean intraprocedural UFR emphasizes its crucial role in the CI-AKI prevention. A strong time-dependence of contrast-induced renal cell cytotoxicityhas been reported [6].

Additional trials are ongoing in order to confirm these preliminary positive findings on Renal Guard system in preventing CI-AKI (Table 1). In particular, only one study compared this strategy with continuous veno-venous hemofiltration(CVVH), which has been reported to be effective in very-high risk population [18]. Bertelli et al., indeed, compared the impact on major events of Renal Guard system (n=33), continuous veno-venous hemofiltration (CVVH; n=35) and conventional hydration (Hy; n=32) in 100 patients with severe CKD scheduled for an elective percutaneous coronary and/or peripheral interventions. In-hospital dialysis occurred in none of Renal Guard patients, 7 (20%) of CVVH patients vs 2 (6.3%) of Hy group.

Trial Design Registration Number
Evaluation of RenalGuard® System to Reduce the Incidence of Contrast Induced Nephropathy in At-Risk Patients (CIN-RG) Standard therapy versus RenalGuard system NCT01456013
Renal Insufficiency Following Contrast Media Administration Trial III (REMEDIAL III) LVEDP-guided hydration versus RenalGuard system NCT02489669
The Use of Renal Guard System in Patients Undergoing CRT Implantation Standard therapy versus RenalGuard system NCT01936142
The Effect of the Forced Diuresis With Matched Hydration in Reducing Acute Kidney Injury During TAVI Standard therapy versus RenalGuard system NCT01866800
RenalGuard System for Prevention of Contrast Induced Nephropathy (REPRECIN) Standard therapy versus RenalGuard system NCT02029820

Table 1: Ongoing studies on the RenalGuard® system in CI-AKI prevention. LVEDP: Left Ventricular End Diastolic Pressure; CRT: Cardiac Resynchronization Therapy.

Futhermore, one of Renal Guard patients died at 6 month, versus 9 (25.7%) CVVH patients and 2 (6.3%) hydration protocol patients (p=0.002). Albeit not significant, CI-AKI occurred less frequently in the Renal Guard patients (15.2%) than CVVH (31.4%) and hydration protocol (25.0%) (p=0.288) [19]. Finally, it should be clarified why UFR did not reach the proposed cutoff in approximately 9% of patients [12,17]. One hypothesis is that the effect of furosemide may be attenuated in the presence of renal artery stenosis.

Contrast-enhanced ultrasound, based on the injection of an intravascular biocompatible tracer (that is, galactose microparticle suspension containing microbubbles [Levovist]), allows the quantification of renal tissue perfusion [20]. This promising noninvasive method seems to be ideal for screening patients with suspectedrenal artery stenosis. Future studies using contrast-enhanced ultrasound should clarify the role of renal artery stenosis on the efficacy of the Renal Guard therapy.


AKI may complicate CM exposure. The Renal Guard system seems to be helpful in preventing CIAKI by allowing a high UFR and maintaining an optimal fluid balance.


  1. ChertowGM, Burdick E, Honour M, Bonventre JV, Bates DW (2005) Acute kidney injury, mortality, length of stay, and costs in hospitalized patients.J Am SocNephrol 16: 3365-3370.
  2. Bellomo R, Kellum JA, Ronco C (2004) Defining acute renal failure: physiological principles.Intensive Care Med 30: 33-37.
  3. Stacul F, van der Molen AJ, Reimer P, Webb JA, Thomsen HS, et al. (2011) Contrast induced nephropathy: updated ESUR Contrast Media Safety Committee guidelines. EurRadiol 21: 2527-2541.
  4. Trivedi HS, Moore H, Nasr S, Aggarwal K, Agrawal A, et al. (2003) A randomized prospective trial to assess the role of saline hydration on the development of contrast nephrotoxicity.Nephron ClinPract 93: C29-34.
  5. Bader BD, Berger ED, Heede MB, Silberbaur I, Duda S, et al. (2004) What is the best hydration regimen to prevent contrast media-induced nephrotoxicity?ClinNephrol 62: 1-7.
  6. Romano G, Briguori C, Quintavalle C, Zanca C, Rivera NV, et al. (2008) Contrast agents and renal cell apoptosis.Eur Heart J 29: 2569-2576.
  7. Stevens MA, McCullough PA, Tobin KJ, Speck JP, Westveer DC, et al. (1999) A prospective randomized trial of prevention measures in patients at high risk for contrast nephropathy: results of the P.R.I.N.C.E. Study. Prevention of Radiocontrast Induced Nephropathy Clinical Evaluation.J Am CollCardiol 33: 403-411.
  8. Liss P, Nygren A, Ulfendahl HR, Erikson U (1999) Effect of furosemide or mannitol before injection of a non-ionic contrast medium on intrarenal oxygen tension.AdvExp Med Biol 471: 353-359.
  9. Solomon R, Werner C, Mann D, D'Elia J, Silva P (1994) Effects of saline, mannitol, and furosemide to prevent acute decreases in renal function induced by radiocontrast agents.N Engl J Med 331: 1416-1420.
  10. Weinstein JM, Heyman S, Brezis M (1992) Potential deleterious effect of furosemide in radiocontrast nephropathy.Nephron 62: 413-415.
  11. Dorval JF, Dixon SR, Zelman RB, Davidson CJ, Rudko R, et al. (2012) Feasibility study of the Renal Guard balanced hydration system: a novel strategy for the prevention of contrast-induced nephropathy in high risk patients. International journal of cardiology166:482-486.
  12. Briguori C, Visconti G, Focaccio A, Airoldi F, Valgimigli M, et al. (2011) Renal Insufficiency After Contrast Media Administration Trial II (REMEDIAL II): Renal Guard System in high-risk patients for contrast-induced acute kidney injury. Circulation 124:1260-1269.
  13. Marenzi G, Ferrari C, Marana I, Assanelli E, De Metrio M, et al. (2012) Prevention of contrast nephropathy by furosemide with matched hydration: the MYTHOS (Induced Diuresis With Matched Hydration Compared to Standard Hydration for Contrast Induced Nephropathy Prevention) trial.JACC CardiovascInterv 5: 90-97.
  14. Usmiani T1, Andreis A, Budano C, Sbarra P, Andriani M, et al. (2016) AKIGUARD (Acute Kidney Injury GUARding Device) trial: in-hospital and one-year outcomes. J Cardiovasc Med (Hagerstown) 17: 530-537.
  15. Visconti G, Focaccio A, Donahue M, Golia B, Marzano A, et al. (2016) Renal Guard System for the prevention of acute kidney injury in patients undergoing transcatheter aortic valve implantation. EuroIntervention 11:e1658-e1661.
  16. Barbanti M, Gulino S, Capranzano P, Imme S, Sgroi C, et al. (2015) Acute Kidney Injury With the Renal Guard System in Patients Undergoing Transcatheter Aortic Valve Replacement: The PROTECT-TAVI Trial (PROphylacticeffecT of furosEmide-induCed diuresis with matched isotonic intravenous hydraTion in Transcatheter Aortic Valve Implantation). JACC CardiovascInterv 8:1595-1604.
  17. Briguori C, Visconti G, Donahue M, De Micco F, Focaccio A, et al. (2016) RenalGuard system in high-risk patients for contrast-induced acute kidney injury. Am Heart J 173: 67-76.
  18. Marenzi G, Marana I, Lauri G, Assanelli E, Grazi M, et al. (2003) The prevention of radiocontrast-agent-induced nephropathy by hemofiltration.N Engl J Med 349: 1333-1340.
  19. Bertelli L, Politi L, Roversi S, Bartolacelli Y, Perrone S, et al. (2012) Comparison Of Renal Guard System, Continuous Venovenous Hemofiltration And Hydration In High-Risk Patients For Contrast-Induced Nephropathy. J Am CollCardiol 59:E96-E96.
  20. Ciccone MM, Cortese F, Fiorella A, Scicchitano P, Cito F, et al. (2011) The clinical role of contrast-enhanced ultrasound in the evaluation of renal artery stenosis and diagnostic superiority as compared to traditional echo-color-Doppler flow imaging. IntAngiol 30:135-139.
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Review summary

  1. Henry Jurk
    Posted on Oct 21 2016 at 5:11 pm
    The authors wrote a review regarding the Renal Guard system, a device designed for hydration therapy in order to prevent contrast-induced acute kidney injury. It would be more interesting to see a more systematic approach of the review and maybe combining results of eligible studies that could possibly be done adding published results of ongoing studies in the near future.

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