Multiple Creatinine Clearance Methods
A
new beta multi-calc was created with specialized handling of patients
with a height below 60 inches. It also contains all of the functionality of
this calculator as well as the calculation of the GFR.
Check it out.....
Patient Name:
Location:
Age:
Scr:
Sex:
Height:
Weight:
For MDRD equation. specify race:
Is the serum creatinine (Scr) currently stable:
Select serum creatinine reference standard: [
more info]
Restrictions
Restrict the maximum calculated clearance to this value:
Cockcroft and Gault equation utilizing the tbw (Total body weight) to
calculate an estimated CrCL - Cockcroft and Gault equation:
CrCl = [(140
- age) x TBW] / (Scr x 72) (x 0.85 for females)
Cockcroft and
Gault equation utilizing the ibw (Ideal body weight) to calculate an
estimated creatinine clearance
Cockcroft and Gault equation:
CrCl =
[(140 - age) x IBW] / (Scr x 72) (x 0.85 for females)
Note: if the
ABW (actual body weight) is less than the IBW use the actual body weight for
calculating the CRCL.
Estimate Ideal body weight in (kg)
Males:
IBW = 50 kg + 2.3 kg for each inch over 5 feet.
Females: IBW = 45.5 kg +
2.3 kg for each inch over 5 feet.
Cockcroft and Gault equation utilizing the adjusted body weight to
calculate an estimated creatinine clearance
CrCl = [(140 - age) x AjBW] / (Scr x 72)
Note: (Multiply result by 0.85 for females)
AjBW = adjusted body weight:
AjBW = IBW + 0.4( ABW - IBW)
Estimated IBW:
Males: IBW = 50 kg +
2.3 kg for each inch over 5 feet.
Females: IBW = 45.5 kg + 2.3 kg for
each inch over 5 feet.
Some studies have shown that utilizing the
adjusted body weight improves accuracy compared to other commonly used
equations in estimating the creatinine clearance in the elderly population.
Simplified 4-variable MDRD study formula:
GFR = 186.3 x (SCR)-1.154 x (age in
years)-0.203 x 1.212 (if patient is black) x 0.742 (if female)
Key point: Early statistical analysis shows very promising results. May
represent the most accurate choice of this group. This may be especially
true in chronic kidney disease.
References
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