NR 341: Week 4 Summary
Acute Kidney and Chronic Kidney Disease; Shock, Sepsis, and
Multiple Organ Dysfunction
Acute Kidney Injury:
It is the SUDDEN decrease in renal function that will lead to the buildup of waste in the blood,
fluid overload, and electrolyte imbalances. AKI can be reversible.
Role of the kidneys: Filters the blood which creates a filtrate called urine. In addition, the
kidneys regulate electrolyte levels, removes waste, and excessive fluid in the body. The kidneys
normally do NOT filter blood cells or proteins.
An adult normally voids 1-2 liters of urine per day
How do the kidneys create urine: Via the nephrons in the kidneys (the heart also plays a role in
this, specifically the blood flow given by the heart to supply the kidneys with blood).
Each kidney contains millions of nephrons. Each nephron receives fresh blood from the heart via
an afferent arteriole.
The nephron consists of two main parts:
Renal Corpuscle (function is to FILTER the blood and create filtrate..hence urine)
Glomerulus
Bowman ’s capsule
Renal Tubule (function is to REABSORB and SECRETE substances IN or OUT of the
filtrate with the assistance of the peritubular capillaries)
Proximal Convoluted Tubule
Loop of Henle
Distal Convoluted Tubule
Collecting Tubule
*In conclusion, there is the flow of substances back in forth from the nephron to the peritubular
capillaries (circulation) until the filtrate is how the body wants it, and then it will leave the body
as urine. Therefore, the tubules are crucial in deciding what should stay or go back into
circulation.
, HOWEVER, when the nephrons are damaged as in INTRARENAL failure this mechanism
is damaged and the patient will experience electrolyte imbalances, decreased glomerular
filtration rate, decreased urinary output, azotemia (increase of BUN and creatinine in the blood…
waste products).
Urine consists of:
Water
Ions: sodium, chloride, calcium, potassium, magnesium, phosphate, bicarbonate
Creatinine*
Urea
Lab work for determining kidney function:
*Creatinine: is a waste product from muscle breakdown and is solely filtered from the
bloodstream via the glomerulus and is NOT reabsorbed or secreted within the nephron.
Therefore, the rate of filtration of creatinine by the glomerulus helps us to determine
the efficiency of the kidneys, which is why we collect blood levels to measure creatinine
levels.
Normal Creatinine level 0.6-1.20 mg/dL
Increasing Creatinine in the body = the kidneys are NOT filtering properly
Creatinine clearance: the amount of blood the kidneys can make per minute that is free
of creatinine.
Normal creatinine clearance: 85-125 mL/min (female) & 95-140 mL/min (men)
A creatinine clearance value along with age, sex, weight, race can help determine the GFR
(glomerular filtration rate).
Glomerular Filtration Rate: rate of blood flow through the kidneys (ml/min). This
shows how well the glomerulus is filtering the blood….great for determining kidney
function.
Normal GFR in adults: 90 or higher ml/min (remember this depends on the patient’s age,
weight, creatinine, sex, and race)
Normal GFR = normal urine output, normal BUN and creatinine, normal electrolyte and water
balance
Acute Kidney and Chronic Kidney Disease; Shock, Sepsis, and
Multiple Organ Dysfunction
Acute Kidney Injury:
It is the SUDDEN decrease in renal function that will lead to the buildup of waste in the blood,
fluid overload, and electrolyte imbalances. AKI can be reversible.
Role of the kidneys: Filters the blood which creates a filtrate called urine. In addition, the
kidneys regulate electrolyte levels, removes waste, and excessive fluid in the body. The kidneys
normally do NOT filter blood cells or proteins.
An adult normally voids 1-2 liters of urine per day
How do the kidneys create urine: Via the nephrons in the kidneys (the heart also plays a role in
this, specifically the blood flow given by the heart to supply the kidneys with blood).
Each kidney contains millions of nephrons. Each nephron receives fresh blood from the heart via
an afferent arteriole.
The nephron consists of two main parts:
Renal Corpuscle (function is to FILTER the blood and create filtrate..hence urine)
Glomerulus
Bowman ’s capsule
Renal Tubule (function is to REABSORB and SECRETE substances IN or OUT of the
filtrate with the assistance of the peritubular capillaries)
Proximal Convoluted Tubule
Loop of Henle
Distal Convoluted Tubule
Collecting Tubule
*In conclusion, there is the flow of substances back in forth from the nephron to the peritubular
capillaries (circulation) until the filtrate is how the body wants it, and then it will leave the body
as urine. Therefore, the tubules are crucial in deciding what should stay or go back into
circulation.
, HOWEVER, when the nephrons are damaged as in INTRARENAL failure this mechanism
is damaged and the patient will experience electrolyte imbalances, decreased glomerular
filtration rate, decreased urinary output, azotemia (increase of BUN and creatinine in the blood…
waste products).
Urine consists of:
Water
Ions: sodium, chloride, calcium, potassium, magnesium, phosphate, bicarbonate
Creatinine*
Urea
Lab work for determining kidney function:
*Creatinine: is a waste product from muscle breakdown and is solely filtered from the
bloodstream via the glomerulus and is NOT reabsorbed or secreted within the nephron.
Therefore, the rate of filtration of creatinine by the glomerulus helps us to determine
the efficiency of the kidneys, which is why we collect blood levels to measure creatinine
levels.
Normal Creatinine level 0.6-1.20 mg/dL
Increasing Creatinine in the body = the kidneys are NOT filtering properly
Creatinine clearance: the amount of blood the kidneys can make per minute that is free
of creatinine.
Normal creatinine clearance: 85-125 mL/min (female) & 95-140 mL/min (men)
A creatinine clearance value along with age, sex, weight, race can help determine the GFR
(glomerular filtration rate).
Glomerular Filtration Rate: rate of blood flow through the kidneys (ml/min). This
shows how well the glomerulus is filtering the blood….great for determining kidney
function.
Normal GFR in adults: 90 or higher ml/min (remember this depends on the patient’s age,
weight, creatinine, sex, and race)
Normal GFR = normal urine output, normal BUN and creatinine, normal electrolyte and water
balance
