Measurement of glomerular filtration rate in ICU patients using 99mTc-DTPA and inulin

Abstract

Improved and reliable methods for assessing glomerular filtration rate (GFR) in intensive care patients are needed in light of known deficiencies using creatinine clearance. We compared simultaneous two-hour clearances of inulin (CIn), creatinine (CCr), and 99mTc-diethylenetriaminepentaacetic acid (CDTPA) in 18 medical or surgical intensive care patients (range, 49 to 92 years old) with blood urea nitrogen (BUN) levels greater than 17.9 mmol/liter (0.5 mg/ml), serum creatinine levels greater than 150 mumol/liter (0.02 mg/ml), or estimated Cockcroft clearance less than 60 ml/min. Patients had severe renal dysfunction with average GFR of 35 ml/min (range, 2 to 69 ml/min). CDTPA and CCr correlated significantly with CIn, although CDTPA tended to provide a closer approximation. Cockcroft clearance (32 +/- 4 ml/min) was grossly similar to CDTPA and CIn and correlated significantly, especially when weight was calculated using actual as opposed to ideal body weight. In a subset of 13 patients with CIn less than 30 ml/min, only CDTPA was significantly correlated with CIn. In patients in the intensive care unit, CDTPA provides a rapid, accurate, and inexpensive clinical assessment of GFR, even at very low GFRs.

Plasmatic cystatin C for the estimation of glomerular filtration rate in intensive care units

“…Other methods have been specifically studied in intensive care: amino-glycoside, 99mTc-DTPA and iohexol clearances [14,15,16]. However, all these techniques are very difficult to apply, expensive and uncommon in clinical practice [12,14].…”

Age-Dependent Changes of the Kidneys: Pharmacological Implications

“…Because of its importance for clinical pharmacology, the correlation between estimated creatinine clearancecalculated by the equation of Cockcroft and Gault [29] and the GFR -measured by 51 Cr-EDTA, inulin clearance, or creatinine clearance determined by urine sampling -was investigated by many authors [10,75,76]. In addition, the formula of Cockcroft and Gault [29] was compared with other formulas of urine-free prediction for creatinine clearance [76][77][78][79][80].…”

“…The result is a decrease in the filtration area of the glomerular basement membrane and a decreased permeability. The glomerular filtration rate (GFR) is reduced with aging [9,10].…”

Formula-Derived Prediction of the Glomerular Filtration Rate from Plasma Creatinine Concentration

“…We excluded studies that used the plasma clearance of a tracer for GFR determination as the gold standard [73, 74, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94], studies that only provided the mean estimate/GFR ratio and its SD [95, 96, 97, 98, 99]or that provided no or insufficient information on both the accuracy and precision of their estimation [69, 70, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112]. Studies of intensive care patients were also excluded, because of the possible interference of bilirubin or dopamine with both the alkaline picrate and enzymatic plasma creatinine assay [113, 114, 115]. Most studies still used CG for GFR estimation.…”