Altered Elimination and Acute Kidney Injury

Vocabulary flashcards covering health assessment terminology, urinalysis values, diagnostic imaging, serum studies, and classification and phases of Acute Kidney Injury (AKI) based on lecture notes.

Anuria

Urine output $<50\,\text{mL/day}$.

Bacteriuria

Bacterial count $>100{,}000\,\text{colonies/mL}$ in the urine.

Dysuria

Painful or difficult voiding.

Enuresis

Involuntary voiding during sleep.

Frequency

Frequent voiding occurring more than every 3 hours.

Nocturia

Awakening during the night to urinate.

Hematuria

Presence of red blood cells in the urine.

Hesitancy

Delay or difficulty in initiating voiding.

Incontinence

Involuntary loss of urine.

Urgency

Strong desire to void.

Urinalysis

Diagnostic test evaluating urine physical characteristics, specific gravity, and pH; detecting protein, glucose, and ketone bodies; and examining sediment for blood cells, casts, and crystals.

Low Specific Gravity

Very dilute urine seen in Diabetes Insipidus, excessive fluid intake, Pyelonephritis, and use of diuretics.

High Specific Gravity

Very concentrated urine seen in Dehydration, Diabetes Mellitus, and Adrenal Insufficiency.

24-hour Urine Collection

Diagnostic test collecting all urine produced over 24 hours (discarding the first voided specimen) to assess kidney function, hormone levels, and metabolic processes.

Renal Ultrasound

Non-invasive imaging test using sound waves to create images of the kidneys, ureters, and bladder to assess size, shape, position, structural abnormalities, and blood flow.

Glomerular Filtration Rate (GFR)

Serum study estimating how well the kidneys filter blood and remove waste; a normal value is above $90\,\text{mL/min/1.73 m}^2$, while values below $60\,\text{mL/min/1.73 m}^2$ suggest kidney disease.

Serum Albumin

Protein produced by the liver that helps maintain fluid balance; normal range is $3.5 - 5.0\,\text{g/dL}$, and low levels can indicate kidney disease (e.g., nephrotic syndrome), malnutrition, or liver disease.

Serum Uric Acid

Waste product of purine metabolism measured in blood; normal range is $3.5 - 7.2\,\text{mg/dL}$, with elevated levels suggesting impaired kidney function, gout, or kidney stone risk.

Intravenous Pyelography

Diagnostic imaging procedure where contrast dye is injected intravenously and X-rays are taken to visualize the kidneys, renal pelvis, and ureters.

Acute Kidney Injury (AKI)

Syndrome encompassing a rapid decline in kidney function indicated by a rise in serum creatinine levels and a reduction in urine output.

Prerenal AKI

Kidney injury caused by decreased blood flow (hypoperfusion) to the kidneys, characterized by a BUN/Creatinine ratio $>20:1$, urine sodium $<20\,\text{mEq/L}$, specific gravity $>1.020$, and increased urine osmolality.

Intrarenal AKI

Kidney injury caused by actual damage to kidney tissue, characterized by a BUN/Creatinine ratio of $10:1\text{ to }15:1$, urine sodium $>40\,\text{mEq/L}$, lower specific gravity ($<1.010$), and presence of urinary sediments/casts.

Acute Tubular Necrosis (ATN)

The cause of 90% of intrarenal AKI cases, resulting from prolonged ischemia or nephrotoxic injury to renal tubular epithelial cells.

Postrenal AKI

Kidney injury caused by obstruction of urine flow (e.g., calculi, strictures, tumors, BPH), leading to reflux into the renal pelvis, hydronephrosis, and tubular blockage.

Initiation Phase of AKI

First phase of AKI starting from the initial insult (e.g., decreased renal perfusion, nephrotoxin exposure) until symptoms become apparent, featuring subtle output/lab changes and reduced GFR.

Oliguric Phase of AKI

Phase lasting 1 to 2 weeks marked by urine output $<400\,\text{mL/day}$, fluid overload, hyperkalemia, hyponatremia, hyperphosphatemia, metabolic acidosis, and uremic symptoms.

Diuretic Phase of AKI

Phase lasting 1 to 3 weeks characterized by a gradual increase in urine output ($3-5\,\text{liters}$ or more per day) with inadequate filtering ability, creating a risk for dehydration, hypokalemia, and hyponatremia.

Recovery Phase of AKI

Phase lasting several months to a year during which kidney function gradually returns to normal and BUN and creatinine levels normalize.

Continuous Renal Replacement Therapy (CRRT)

Renal replacement therapy used primarily in critical care settings for hemodynamically unstable AKI patients, providing slower and more controlled fluid and solute removal than intermittent hemodialysis.