Contrast-induced nephrotoxicity (CIN), which is defined as a 25% or greater increase in serum creatinine from baseline or an absolute increase of at least 0.5 mg/dL 48 to 72 hours after the administration of the contrast media that cannot be attributed to other causes, occurs in 1% to over 50% of patients undergoing coronary angiographic procedures. When CIV occurs following coronary catherization, it has been associated with a fourfold increased risk of 90-day death, need for dialysis, or persistent kidney injury. Therefore, it is essential to find modalities to mitigate this untoward effect.

Periprocedural intravascular hydration as well as withdrawing nephrotoxic agents prior to contrast media administration are standards of care. When conducting these mitigation strategies, all efforts must be made to limit fluid overload, especially in patients with heart failure or chronic kidney disease (CKD). Renal Guard is a real-time, automated fluid-matching device; however, its use is limited by cost and availability.

The CINEMA trial is a prospective, open-label, controlled trial conducted over a 28-month period to evaluate the potential benefits of a nonautomated match hydration and forced diuresis (MHFD) protocol compared with current hydration protocols in the prevention of CIN in patients with CKD undergoing coronary procedures.

To be included in the trial, patients had to be aged 18 to 85 years, have an estimated glomerular filtration rate (eGFR) <60 mL/min/1.73m2 and require elective or urgent coronary angiography or, when indicated, percutaneous coronary intervention (PCI). Exclusion criteria included allergy to furosemide, the presence of severe left ventricular dysfunction (LVEF <35%), an ST-elevated myocardial infarction (STEMI) with the need for primary PCI, cardiogenic shock, acute respiratory insufficiency, administration of IV contrast media within 10 days prior to the procedure, planned contrast-enhanced procedure within 3 days after the procedure, difficult placement of the Foley catheter, use of reno-protective drugs (which were not defined), or need for dialysis.

The primary endpoint of this study was the development of CIN. Secondary endpoints were CIN requiring renal replacement therapy, significant arrhythmias, cardiogenic shock, pulmonary edema, and death.

Patients in the MHFD group received a 250 mL IV bolus of normal saline over 30 minutes followed by a bolus dose of furosemide 0.5 mg/kg. Once urine flow rate was greater than 300 mL/hour, the contrast media was administered. MHFD was continued throughout the cardiac procedure and up to 4 hours following the procedure. MHFD was achieved by initially administering normal saline IV at a rate of 200 mL/hour with adjustments to maintain a urine output of greater than 300 mL/hour every 5 minutes. The control group received continuous IV isotonic saline at a rate of 1-1.5 mL/kg for at least 12 hours before and 12 hours after PCI.

A total of 1205 patients with a mean age of 62.3 years and a mean eGFR of 46.37 mL/min/1.73m2 were included in the study. Of these patients, 90% underwent elective procedures while 10% required urgent angiography due to the occurrence of non-STEMI myocardial infarction. Patients were randomized 2:1 with 799 patients receiving MHFD and 406 receiving standard treatment.

Differences in the study populations included younger age and a higher prevalence of diabetes, hypertension, smoking, peripheral arterial disease, insulin use, and frequency of PCI in the MHFD group. Both groups had similar rates of elective and urgent procedures, as well as other CIN risk factors (i.e., baseline eGFR, contrast volume, use of nephrotoxic drugs).

Investigators found that while CIN was significantly higher among patients who had underwent elective procedures versus urgent procedures (9% vs. 1%, respectively), there was a statistically significant difference in the development of CIN in favor of the MHFD group. In the MHFD group, 8.01% of patients developed CIN compared with 14.04% in the control group (P <.001). Patients who underwent elective procedures benefited most from MHFD. There was no difference in the frequency of adverse events between the intervention and the control groups.

This study provides useful information for pharmacists by demonstrating the value of MHFD over standard hydration protocols in patients requiring contrast media for coronary procedures.

The content contained in this article is for informational purposes only. The content is not intended to be a substitute for professional advice. Reliance on any information provided in this article is solely at your own risk.

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