Approach to Best Practices for Adult DRS: Patient Preparation and Acquisition

ParameterBest practice
Patient preparation
 Increase in fluid intake day before and morning of examinationIt may be optimal also to have patient avoid natural diuretics, though some experts believe effect is less than fluid consumed
 Withdrawal of prescribed diuretics on morning of examinationThiazides: hydrochlorothiazide, indapamide, metolazone, chlorthalidone
Loop diuretics: furosemide, bumetanide, torsemide, ethacrynic acid
Potassium sparing: amiloride, spironolactone, triamterene, eplerenone
Carbonic anhydrase inhibitors: acetazolamide
 Oral hydration 30–60 min beforehandPatient drinks 5–10 mL/kg
 450–900 mL (15–30 oz, or 2–4 cups) for adults weighing 90.7 kg (200 lb)
 385–770 mL (13–26 oz, or 1.5–3 cups) for adults weighing 77.1 kg (170 lb)
 PrevoidingPatient voids immediately before beginning of examination
 99mTc-MAG3, 37–185 MBq (1–5 mCi) intravenously99mTc-MAG3 is preferred over 99mTc-DTPA despite cost; lower doses are adequate given that flow/arterial phase can be omitted
 Furosemide, 40 mg intravenouslyIf patient is on higher dose of furosemide at home, increase to match; consider 80–120 mg if known renal insufficiency
 Serum creatinine level > 1.2 ng/dL (women) or > 1.4 ng/dL (men)
 Estimated GFR < 90 mL/min/1.73 m2 (either sex)
 Acquisition and timing of diuretic (most common source of variability; remains actively debated topic with no clear best practice for all situations)F=0 single acquisition or F+20 2-part acquisition; F+10, F+15, and F+30 are also used by many practices, and F+10sp is also considered suitable technique
 Postvoid image (maximizes pressure differential between kidneys and bladder, facilitating physiologic drainage)Patient stands or walks for 5 min, voids, and then is imaged in same position as examined
  • Many quantitative values are dependent on protocol and cannot be universally applied.