Acute Kidney Injury and Kidney Replacement Therapy in the Critically Ill Patient
RIFLE
AKIN
KDIGO
All Three
Classification
Systems
Stage
SCr/GFR Criteria
Stage
SCr Criteria
Stage
SCr Criteria
UOP Criteria
L
Complete loss of
function for > 4 wk
E
Complete loss of
function for > 3 mo
AKI = acute kidney injury; AKIN = Acute Kidney Injury Network; GFR = glomerular filtration rate; KDIGO = Kidney Disease: Improving Global Outcomes; KRT =
kidney replacement therapy; RIFLE = risk (R), injury (I), failure (F), loss (L), end-stage kidney disease (E); SCr = serum creatinine; UOP = urinary output.
Kidney dysfunction/damage is a spectrum.
In 2012, KDIGO proposed four categories to encompass the spectrum of kidney function (Figure 1;
No known kidney disease (NKD)
ii.
AKI: Acute kidney dysfunction over 7 days or less
iii.
Acute kidney disease (AKD): For those who meet the AKI definition or with other types of
kidney dysfunction/damage for less than 3 months
iv.
Chronic kidney disease (CKD): Kidney dysfunction/damage for more than 3 months
The definitions were intended to improve consistency in applied nomenclature in care, research, and
public health and to identify patients with AKD who may need therapy to restore kidney function
and mitigate or reverse kidney damage.
The definition of AKI recovery is not well defined; however, identification of early resolution
within days versus delayed resolution of weeks to months, has important prognostic implications.
Nonresolving AKI is associated with greater risk of major adverse kidney events, specifically the
development of chronic kidney disease.
| d. | Increasingly, patients in the AKD subgroup are targeted for interventions designed to prevent CKD |
|---|
development, including bundled strategies delivered in AKI follow-up clinics. Interprofessional
survivor clinics for AKI are reported to improve patient education, engagement, follow-up, and
outcomes. Pharmacists can play a central role in such initiatives by providing a careful medication
evaluation (renally eliminated and nephrotoxic drugs), monitoring and supportive care for key
concurrent conditions (e.g., hypertension, lipid management), and patient and caregiver education.
Abbreviations: AKD, acute kidney disease; AKI, acute kidney injury; CKD, chronic kidney disease; NKD, no known kidney disease.
NKD