N-Acetylcysteine to Prevent Radiocontrast Nephropathy in Emergency Department Patients
Condition: Radiocontrast Nephropathy
MeSH terms: Kidney Diseases; Emergencies
Study type: Interventional
Phase: Phase 2

Summary: 
      Multiple agents have been studied to prevent radiocontrast nephropathy. One of these agents
      is N-Acetylcysteine. Previous trials to assess N-Acetylcysteine's efficacy in the prevention
      of contrast nephropathy have been promising. However, previous studies have limited
      applicability to the Emergency Department (ED) patient population for two reasons:

        -  1) Many of the pretreatment strategies employed in these studies take several hours or
           even days to perform, which is not feasible in acutely ill ED patients.

        -  2) Most of these studies were conducted in patients undergoing cardiac catheterization.
           This may be a very different population than patients in the ED undergoing abdominal or
           chest computed tomography.

      The investigators wish to study the efficacy of N-acetylcysteine as an agent to prevent
      radiocontrast nephropathy in ED patients undergoing computerized tomography. The
      investigators propose a randomized, double-blind, controlled trial comparing saline hydration
      plus N-acetylcysteine versus saline hydration alone. The hypothesis of this study is that
      N-acetylcysteine with normal saline will be more effective than saline alone in the
      prevention of radiocontrast nephropathy.
    

Detailed description: 
      Out of the approximately 110 million Emergency Department (ED) visits in the United States
      each year approximately 8.8 million people undergo Contrast-Enhanced Computerized Tomography
      (CT) studies in United States EDs each year (based on the investigators experience).

      Radiocontrast nephropathy is a serious potential consequence associated with significant
      morbidity and mortality. Preliminary data suggests that the rate of Radiocontrast Induced
      Nephropathy after Emergency Department CT is approximately 5-7%. This figure, coupled with
      our estimate of 8.8 million contrast-enhanced CT studies, suggests that there are somewhere
      between 440,000 and 616,000 cases of radiocontrast nephropathy in the US each year that are
      caused by ED studies.

      Multiple agents have been studied to prevent radiocontrast nephropathy. One of these agents
      is N-Acetylcysteine. There is inconclusive evidence about the benefit of this intervention.
      Some studies have shown that N-Acetylcysteine administered in either a high-dose intravenous
      protocol or a low-dose intravenous plus oral protocol may reduce the incidence of
      radiocontrast nephropathy in patients undergoing emergent cardiac catheterization, although
      other studies have found no benefit.

      It is not clear, however, if these studies generalize to the ED patient undergoing emergency
      CT. ED patients often have different comorbidities or higher acuity which may limit the
      applicability in the ED patient population for two reasons:

        -  1) Many of the pretreatment strategies employed in these studies take several hours or
           even days to perform, which is not feasible in acutely ill ED patients.

        -  2) Most of these studies were conducted in patients undergoing cardiac catheterization.
           This may be a very different population than patients in the ED undergoing abdominal or
           chest computed tomography.

      The investigators wish to study the efficacy of N-acetylcysteine as an agent to prevent
      radiocontrast nephropathy in ED patients undergoing computerized tomography. The
      investigators propose a randomized, double-blind, controlled trial comparing saline hydration
      plus N-acetylcysteine versus saline hydration alone. The hypothesis of this study is that
      N-acetylcysteine with normal saline will be more effective than saline alone in the
      prevention of radiocontrast nephropathy.
    

Intervention name(s): N-Acetylcysteine (NAC); 0.9% Sodium-chloride
Intervention type(s): Drug; Drug
Intervention description(s): Experimental:
Before CT: 3 g NAC IV in 500 cc of 0.9% Sodium-chloride
After CT: 200 mg NAC/hour in 0.9% Sodium-chloride at 67 cc/hour for up to 24 hours.; Placebo:
Before CT: 500 cc 0.9% Sodium-chloride
After CT: NS at 67 cc/hour for up to 24 hours.
Other intervention name(s): Acetadote; Normal Saline
Intervention MeSH terms: Acetylcysteine; N-monoacetylcystine
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: Subjects will be randomized to receive either of two interventions: N-acetylcysteine (Treatment group) or Normal Saline (Placebo group).
Patients in the treatment group will receive 3 g of Nacetylcysteine in 500mL normal saline (0.9% Sodium Chloride) solution during 30 minutes before contrast administration. After contrast administration, patients will receive a continuous infusion of 200mg of N-acetylcysteine per hour, administered as an infusion of 67 mL per hour of a solution of 3 g of N-acetylcysteine diluted to a total volume of 1,000 mL with normal saline solution.
Patients in the placebo group will receive 500 mL of normal saline solution during 30 minutes before contrast administration and a continuous infusion of 67 mL per hour of normal saline solution after contrast administration.
Patients in both arms will receive the postcontrast infusion (N-acetylcysteine or saline solution) for a minimum of 2 hours.
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary purpose: Prevention
Keywords: NAC; Radiocontrast Nephropathy; N-Acetylcysteine; RCN; RCIN; Creatinine; Computerized Tomography; CT; Emergency Department; ED