Altered Urinary Elimination: AKI, CKD, and Dialysis Vocabulary

50 vocabulary flashcards covering renal physiology, serum diagnostics, acute kidney injury, chronic kidney disease, renal diet, and dialysis modalities from the lecture notes.

Nephron

The functional unit of the kidney responsible for urine formation, composed of the glomerulus, Bowman's capsule, and tubular system.

Glomerular Filtration Rate (GFR)

The volume of blood filtered by the glomeruli per minute, normally equal to approximately $125\,\text{mL/min}$.

Glomerulus

A specialized capillary bed within the nephron where blood filtration occurs at a rate of $125\,\text{mL/min}$.

Bowman's Capsule

The double-walled cup surrounding the glomerulus that collects the fluid filtered from the blood.

Proximal Convoluted Tubules

The segment of the renal tubular system where the reabsorption of essential electrolytes into capillaries primarily takes place.

Loop of Henle

The U-shaped segment of the nephron tubule that concentrates the renal filtrate.

Distal Convoluted Tubules

The tubule segment regulated by antidiuretic hormone and aldosterone that reabsorbs $\text{HCO}_3^-$ and secretes $\text{H}^+$.

Erythropoietin

A renal hormone produced in response to hypoxia and decreased renal perfusion that stimulates red blood cell production in bone marrow.

Renin-Angiotensin-Aldosterone System (RAAS)

A hormone pathway activated by the kidneys for blood pressure regulation, in which Angiotensin II causes the release of Aldosterone.

Creatinine Clearance

A calculated indicator of GFR with a normal reference range of $70\text{--}135\,\text{mL/min/1.73m}^2$, requiring serum creatinine testing during collection.

Blood Urea Nitrogen (BUN)

A serum diagnostic measure with a normal level of $6\text{--}20\,\text{mg/dL}$, regulated by renal excretion of urea and increased in kidney damage, dehydration, GIB, or muscle injury.

Serum Creatinine

A waste product released at a constant rate with a normal level of $0.6\text{--}1.3\,\text{mg/dL}$, serving as a reliable indicator of kidney function.

Serum Uric Acid

The end product of purine metabolism excreted by the kidneys, which elevated levels may indicate renal dysfunction, gout, or medication effects.

Serum Sodium

An electrolyte with a standard reference range of $135\text{--}145\,\text{mEq/L}$ that alters during renal dysfunction or endocrine disorders.

Acute Kidney Injury (AKI)

A rapid decrease in renal function lasting approximately $2\text{--}4$ weeks, carrying a generally good prognosis if identified early.

Azotemia

An accumulation of nitrogenous waste products such as urea and creatinine in the blood due to impaired renal excretion.

Prerenal AKI

A category of acute kidney injury resulting from external factors that decrease renal blood flow, such as hypovolemic shock or heart failure.

Intrarenal AKI

Acute kidney injury caused by direct damage to kidney tissue and nephron function, including nephrotoxins, NSAIDs, or glomerulonephritis.

Postrenal AKI

A type of acute kidney injury resulting from mechanical obstruction of urine outflow, leading to urine backing up into the renal pelvis.

Acute Tubular Necrosis (ATN)

A potentially reversible condition caused by intrarenal AKI involving disruption of the basement membrane and destruction of tubular epithelium.

Hydronephrosis

Distension and dilation of the renal pelvis caused by urine outflow obstruction in postrenal AKI.

Onset Phase of AKI

The initial period of AKI triggered by an event, lasting hours to days, where patients are mostly asymptomatic with minimal changes in GFR.

Oliguric Phase of AKI

The phase of AKI lasting $1\text{--}2$ weeks, marked by a significant drop in urine output, fluid retention, azotemia, metabolic acidosis, and Kussmaul respirations.

Diuretic Phase of AKI

The recovery phase of AKI lasting $1\text{--}3$ weeks, characterized by osmotic diuresis and a high urine output exceeding $3\,\text{L/day}$.

Recovery Phase of AKI

The final stage of AKI involving kidney tissue repair, GFR increase, and normalization of BUN and Cr, lasting up to $12$ months.

Chronic Kidney Disease (CKD)

A progressive, irreversible loss of kidney function defined by kidney damage or a GFR less than $60\,\text{mL/min/1.73m}^2$ for longer than $3$ months.

End-Stage Renal Disease (ESRD)

The final stage of chronic renal failure characterized by a GFR dropping below $15\,\text{mL/min}$.

Kussmaul Respirations

A deep and rapid breathing pattern developed by the body to compensate for metabolic acidosis in AKI or CKD.

Uremic Pericarditis

Inflammation of the pericardium caused by the accumulation of uremic toxins in chronic renal failure.

Renal Osteodystrophy

A musculoskeletal disorder in CKD resulting from altered calcium and phosphorus regulation, causing bone pain and elevated fracture risk.

Renal Diet Fluid Restriction

A fluid management strategy aimed at limiting interdialytic weight gain to $1\text{--}3\,\text{kg}$ between treatments.

Renal Diet Sodium Restriction

A dietary limitation varying around $2\,\text{g/day}$, requiring avoidance of processed sodium-rich foods and salt substitutes.

Renal Diet Potassium Restriction

A dietary limit of approximately $2\,\text{g/day}$ that restricts high potassium foods and potassium-containing salt substitutes.

Renal Diet Phosphate Restriction

A dietary limit of approximately $1\,\text{g/day}$, often combined with administration of phosphate binders during meals.

Renal Diet Protein Moderation

A intake guideline of $1.2\,\text{g/kg/day}$ in late CKD stages to prevent negative nitrogen balance while avoiding excess nitrogenous waste.

Renal Replacement Therapy (RRT)

Life-sustaining modalities required when GFR falls below $15\,\text{mL/min/1.73m}^2$ or life-threatening uremic complications occur.

Dialysis

A therapeutic technique involving the movement of fluid and solutes across a semi-permeable membrane to treat renal failure.

Diffusion

The movement of solutes such as urea, creatinine, potassium, and phosphate from an area of higher concentration to lower concentration across a membrane.

Osmosis

The movement of fluid across a semi-permeable membrane from an area of lower solute concentration to higher solute concentration.

Ultrafiltration

The removal of water and fluid during dialysis driven by a pressure gradient across a semi-permeable membrane.

Hemodialysis (HD)

An RRT modality first used in $1943$ where blood is circulated through an external dialyzer $3$ days a week for $4$ hours per session.

Vascath

A dual-lumen temporary hemodialysis catheter placed in the subclavian, jugular, or femoral vein that can be used immediately upon verification.

Arteriovenous Fistula (AVF)

A surgical connection created by joining an artery directly to a vein in the arm, requiring $6\text{--}8$ weeks to mature before use.

Arteriovenous Graft (AVG)

A permanent vascular access created by connecting an artery and vein with a synthetic bridge graft, requiring $2\text{--}4$ weeks before use.

Steal Syndrome

A complication of vascular access where blood is diverted away from the distal extremity, causing localized ischemia.

Thrill and Bruit

Physical signs of vascular access patency assessed by palpating a vibration (thrill) and listening for a swishing sound (bruit).

Disequilibrium Syndrome

A central nervous system complication of hemodialysis triggered by rapid fluid and solute clearance from the blood.

Peritoneal Dialysis (PD)

An RRT method introduced in $1923$ using the patient's peritoneal membrane as a semi-permeable filter accessed via a catheter.

Automated Peritoneal Dialysis (APD)

A popular nocturnal PD method executing $4$ or more automated exchanges per night, each lasting $1\text{--}2$ hours.

Continuous Ambulatory Peritoneal Dialysis (CAPD)

A manual PD method performed during waking hours consisting of $4$ daily exchanges utilizing strict aseptic technique.