The prevention of contrast-induced nephropathy by simultaneous hemofiltration during coronary angiographic procedures: a comparison with periprocedural hemofiltration

Contrast-induced acute kidney injury and its contemporary prevention

The complexity and application range of interventional and diagnostic procedures using contrast media (CM) have recently increased. This allows more patients to undergo procedures that involve CM administration. However, the intrinsic CM toxicity leads to the risk of contrast-induced acute kidney injury (CI-AKI). At present, effective therapy of CI-AKI is rather limited. Effective prevention of CI-AKI therefore becomes crucially important. This review presents an in-depth discussion of CI-AKI incidence, pathogenesis, risk prediction, current preventive strategies, and novel treatment possibilities. The review also discusses the difference between CI-AKI incidence following intraarterial and intravenous CM administration. Factors contributing to the development of CI-AKI are considered in conjunction with the mechanism of acute kidney damage. The need for ultimate risk estimation and the prediction of CI-AKI is stressed. Possibilities of CI-AKI prevention is evaluated within the spectrum of existing preventive measures aimed at reducing kidney injury. In particular, the review discusses intravenous hydration regimes and pre-treatment with statins and N-acetylcysteine. The review further focuses on emerging alternative imaging technologies, alternative intravascular diagnostic and interventional procedures, and new methods for intravenous hydration guidance; it discusses the applicability of those techniques in complex procedures and their feasibility in current practise. We put emphasis on contemporary interventional cardiology imaging methods, with a brief discussion of CI-AKI in non-vascular and non-cardiologic imaging and interventional studies.

The Pathophysiology and the Management of Radiocontrast-Induced Nephropathy

Contrast-induced nephropathy (CIN) is an impairment of renal function that occurs after the administration of an iodinated contrast medium (CM). Kidney dysfunction in CIN is considered transient and reversible in most cases. However, it is the third most common cause of hospital-acquired acute kidney injury and is associated with increased morbidity and mortality, especially in high-risk patients. Diagnostic and interventional procedures that require intravascular CM are being used with increasing frequency, especially among the elderly, who can be particularly susceptible to CIN due to multiple comorbidities. Therefore, identifying the exact mechanisms of CIN and its associated risk factors is crucial not only to provide optimal preventive management for at-risk patients, but also to increase the feasibility of diagnostic and interventional procedure that use CM. CM induces kidney injury by impairing renal hemodynamics and increasing the generation of reactive oxygen species, in addition to direct cytotoxicity. Periprocedural hydration is the most widely accepted preventive strategy to date. Here, we review the latest research results on the pathophysiology and management of CIN.

Iodinated contrast medium: Is there a re(n)al problem? A clinical vignette-based review

As we were taught, for decades, that iodinated contrast-induced acute kidney injury should be dreaded, considerable efforts were made to find out effective measures in mitigating the renal risk of iodinated contrast media. Imaging procedures were frequently either downgraded (unenhanced imaging) or deferred as clinicians felt that the renal risk pertaining to contrast administration outweighed the benefits of an enhanced imaging. However, could we have missed the point? Among the abundant literature about iodinated contrast-associated acute kidney injury, recent meaningful advances may help sort out facts from false beliefs. Hence, there is increasing evidence that the nephrotoxicity directly attributable to modern iodinated CM has been exaggerated. Failure to demonstrate a clear benefit from most of the tested prophylactic measures might be an indirect consequence. However, the toxic potential of iodinated contrast media is well established experimentally and should not be overlooked completely when making clinical decisions. We herein review these advances in disease and pathophysiologic understanding and the associated clinical crossroads through a typical case vignette in the critical care setting.

Current comments on contrast media administration in patients with renal insufficiency

Contrast media administration has been associated with complications such as nephropathy, cardiovascular morbidity, and neurovascular events, particularly in patients with renal insufficiency. This association has been questioned in recent studies. This review was performed to summarize the most current evidence on contrast induced nephropathy (CIN), contributing factors, and considerations in patients with renal insufficiency. The risk of CIN was over-estimated by the previous studies, due to a lack of control groups or presence of non-randomized control groups, which led to a selection bias. However, the thresholds associated with an increased risk of CIN are controversial and require risk-benefit analysis on an individual basis. Regarding the administration of contrast media (CM) in the emergency setting, the majority of studies suggested that CM exposure does not meaningfully increase the risk of acute kidney injury in critically ill patients (including trauma patients). Several strategies have been suggested to reduce the risk of CIN, including volume expansion to increase renal blood flow, sodium bicarbonate or N-acetylcysteine administration, and use of low-osmolal contrast media in end-stage renal disease.

The Prevention and Management of Contrast-induced Acute Kidney Injury: A Mini-review of the Literature

Contrast-induced acute kidney injury, also called contrast-induced nephropathy, is one of the main causes of acute renal failure/acute kidney injury (AKI) in hospitalized patients within 48 to 72 hours of contrast media administration during various radiologic procedures. Several factors can be responsible for contrast-induced acute tubular necrosis (ATN); however, patient and procedure-related factors play the lead role in determining the development of contrast-induced nephropathy. There is no definitive treatment and hydration remains the mainstay preventive strategy. This article will review the incidence, criteria for definitive diagnosis, and an effective approach on how to prevent contrast-induced nephropathy in a clinical setup.

Post-contrast acute kidney injury. Part 2: risk stratification, role of hydration and other prophylactic measures, patients taking metformin and chronic dialysis patients : Recommendations for updated ESUR Contrast Medium Safety Committee guidelines

OBJECTIVES

The Contrast Media Safety Committee (CMSC) of the European Society of Urogenital Radiology (ESUR) has updated its 2011 guidelines on the prevention of post-contrast acute kidney injury (PC-AKI). The results of the literature review and the recommendations based on it, which were used to prepare the new guidelines, are presented in two papers. AREAS COVERED IN PART 2: Topics reviewed include stratification of PC-AKI risk, the need to withdraw nephrotoxic medication, PC-AKI prophylaxis with hydration or drugs, the use of metformin in diabetic patients receiving contrast medium and the need to alter dialysis schedules in patients receiving contrast medium.

KEY POINTS

• In CKD, hydration reduces the PC-AKI risk • Intravenous normal saline and intravenous sodium bicarbonate provide equally effective prophylaxis • No drugs have been consistently shown to reduce the risk of PC-AKI • Stop metformin from the time of contrast medium administration if eGFR < 30 ml/min/1.73 m 2 • Dialysis schedules need not change when intravascular contrast medium is given.

Effect of trimetazidine on preventing contrast-induced nephropathy in diabetic patients with renal insufficiency

BACKGROUND

Our study sought to assess the effect of trimetazidine (TMZ) on preventing contrast-induced nephropathy (CIN) in diabetic patients with renal insufficiency.

MATERIALS AND METHODS

106 diabetic patients with renal insufficiency who were undergoing coronary angiography (CAG) and/or percutaneous coronary intervention (PCI) were enrolled in this study. Standard hydration was administered to both groups (the TMZ group and the control group). In the TMZ group, patients were orally administered TMZ for 48 hours before and 24 hours after CAG and/or PCI. Serum creatinine (Scr), cystatin C and the glomerular filtration rate (eGFR) were measured before as well as 24 hours, 48 hours and 72 hours after contrast media injection. The incidence of CIN and major cardiovascular events (MACE) was also evaluated in both groups.

RESULTS

Scr, cystatin C and the eGRF in the TMZ group were better than those in the control group after 24 hours (OR: 0.78, 95% CI: 0.54-0.82; OR: 0.66, 95% CI: 0.62-0.73; OR: 1.2, 95% CI: 1.02-1.53, respectively), 48 hours (OR: 0.69, 95% CI: 0.52-0.73; OR: 0.76, 95% CI: 0.69-0.84; OR: 1.5, 95% CI: 1.25-1.68, respectively) and 72 hours (OR: 0.82, 95% CI: 0.77-0.91; OR: 0.85, 95% CI: 0.71-0.92; OR: 1.67, 95% CI: 1.33-1.72, respectively). The incidence of CIN (9.26% vs 16.67%) and MACE (7.41% vs 18.51%) in the TMZ group was significantly lower than that in the control group (P < 0.05).

CONCLUSIONS

Our study suggests that TMZ could reduce the incidence of CIN and MACE in diabetic patients with renal insufficiency who are undergoing CAG and/or PCI.