I’d like to thank Rani for the detailed and comprehensive reply which I’ll make sure to benefit from in my practice.
I’d like to clarify that the concern with UpToDate calculator is also valid for younger patients as it considers the patient weight rather than ideal or adjusted body weight when necessary in contrast to Micromedix calculator which adjusts weight as necessary.
Regarding the inquiry about how to assess renal function in AKI patients, the following are my thoughts:-
1- AKI is usually precipitated by causes that affect other factors related to production and excretion of creatinine which makes it difficult to use the commonly used equations that necessitate a stable creatinine level.
2- As per our practice, I recommend to combine two main parameters to judge the kidney function in patients with AKI:-
a) Urine output:- As a measure of the functionality of the kidney. Patient with anuria should be assumed to have a CrCl of less than 10 ml/min regardless of the equation result
b) Original MDRD equation:- As it contains parameters like (Albumin) and (BUN) which are usually altered by the conditions that can lead to AKI.
3- Consider the degree of AKI and treatment required, i.e Spontaneously resolving VS CRRT-managed; in adjusting the dose as per specific drug monograph.
To conclude, combining equations and clinical status of the patient is essential for drug adjustment in patients with AKI taking into consideration the management of precipitating factors for developing AKI.