Urine_output_fluid_balance_Calculation v.1

Calculates the urine output rate and fluid balance, based on fluid intake and total urine output under a specified interval of time. Urine output rate {ml/kg/hr} = total urine output {ml} / (weight {kg} x specified interval {hours}); Fluid balance {ml} = fluid intake {ml} - total urine output {ml}. These calculations help identify oliguria, defined as urine output <500 ml in 24 hr (0.5 ml/kg/h) in an adult, and <1 L in 24 hr (1 mL/kg/h) in a child; acute kidney injury (AKI) or acute renal failure (ARF).

Eneimi Allwell-Brown

models@cambiocds.com

© Cambio Healthcare Systems

To determine the urine output rate and fluid balance and help identify individuals with oliguria, possible AKI or ARF.

Calculate urine output rate and fluid balance over a specified time interval. Urine output rate {ml/kg/hr} = total urine output {ml} / (weight {kg} x specified interval {hours}); Fluid balance {ml} = fluid intake {ml} - total urine output {ml}. Also use to identify individuals with oliguria [urine output <500 ml in 24 hr (0.5 ml/kg/h) in an adult, and <1 L in 24 hr (1 mL/kg/h) in a child]. With RIFLE (Risk, Injury, Failure, Loss of kidney function, and End-stage kidney disease) classification, it also helps identify individuals with: - High risk AKI: less than 0.5 ml/kg/hr for more than 6 hours at a time; - Positive AKI diagnosis: less than 0.5 ml/kg/hr for more than 12 hours at a time; - Acute renal failure: less than 0.3 ml/kg/hr for more than 24 hours at a time or anuria for 12 hours.

Israni AK, Kasiske BL. Laboratory assessment of kidney disease: glomerular filtration rate, urinalysis, and proteinuria. Brenner and Rector’s the kidney. 2012;9. Lopes JA, Jorge S. The RIFLE and AKIN classifications for acute kidney injury: a critical and comprehensive review. Clinical Kidney Journal. 2013 Feb 1;6(1):8-14.

OBSERVATION.body_weight.v2, OBSERVATION.urine_output.v1, OBSERVATION.fluid_balance.v1