Microsoft word - cin - risk assessment and prevention strategies

Contrast induced nephropathy
Risk assessment and prevention strategies
 
Risk assessment
Chronic renal disease (CRD) is the single biggest predictor of contrast induced nephropathy CIN and CRD is highly unlikely in the absence of risk factors listed below. Risk factors for acute or chronic renal impairment and/or development of CIN.
 Cardio-Vascular disease (hypertension, congestive heart disease, cardiac or peripheral  Nephrotoxic Drugs - loop diuretics, amphotericin B, aminoglycosides, vancomycin, non steroidal anti inflammatory drugs, cancer and immune suppressant chemotherapy.  Human immunodeficiency syndrome or acquired immunodeficiency syndrome Further stratification can be based on glomerular filtration rate (GFR):
30 – 60 ml/min
< 30 ml/min
Although absolute values of creatinine are less accurate they are nevertheless commonly used in practice when making decisions on risk of CIN. A serum creatinine < 130 mmol/L is considered low risk when in isolation. In patients with no risk factors and GFR > 60 ml/min then risk for CIN is negligible. Prevention strategies
Hydration strategies
If patients with no risk factors are poorly hydrated then rehydration is indicated with normal saline, but no specific preventative strategies are required. In patients with 1 risk factor and /or GFR 30 - 60 then there is moderate risk (1-10%) for CIN.
Hydration strategies should be used if the contrast cannot be avoided or deferred. In the Emergency
Updated May 2012
 Department (ED) setting this means giving a minimum of 300-500 mls over a period of 30 minutes - 4 hours, depending on the urgency of the test required, and continuing this for 12 hours at 1ml/kg/hr for 12 hours. Where fluid overload is a risk this should be assessed on a case by case basis, with the use of N acetyl cysteine (NAC) a possibility where fluid is contraindicated but the majority of patients will tolerate fluid and the evidence for using NAC is weak. In patients with 2 or more risk factors and /or GFR < 30 then there is high risk (10-80%) for CIN.
Check again - can this test be avoided? If not, hydrate with normal saline as below.
Hydration strategies for moderate and high risk patients:
Hydration with Saline Guidelines
1 ml/kg/hr (MAX 100 ml/hr) 12 hours pre & 12 hours post contrast
If CHF or left ventricular ejection fraction (LVEF) < 40% then 0.5 ml/kg/hr (MAX 50 ml/hr) 12
hours pre & post contrast (24 hour total infusion duration)

Emergent procedure:
Fluid bolus of minimum 300-500 mls up to 1 litre as tolerated prior (30 minutes-2 hours) to
procedure. Hydration during procedure and/or 12 hrs after if possible as above (dependent on
clinical status)

N acetyl cysteine (NAC)
NAC is still used in some institutions but it is advised for use in high risk patients only. The guideline below is a commonly used regimen. Evidence for benefit is lacking while accepted limited risk exists. Acetylcysteine Dosing Guidelines
Non acute: 600-1200 mg PO Q12h X 4 doses
2 doses pre-contrast and 2 doses post-contrast is optimal
Emergent Procedure
1 dose before and 3 doses post cath or procedure is acceptable (Q12h x 4 doses total)
IV Acetylcysteine
600-1200 mg IV x 1 over 15 minutes, then 600-1200 mg PO/PT Q12h x 4 doses post-procedure

Sodium bicarbonate
This is no longer considered useful in CIN preventative strategies. Metformin
Metformin is excreted unchanged by the kidneys and is not metabolized by the liver. It is recommended that the dose of metformin should be reduced when the GFR is between 30-60 ml/min and its use is not recommended when the GFR is <30 ml/min. Updated May 2012

Source: http://www.ecinsw.com.au/sites/default/files/field/file/CIN%20-%20Risk%20assessment%20and%20prevention%20strategies.pdf