Acute Kidney Injury Flashcards
What is renal failure?
The kidneys’ inability to filter waste and maintain fluid, electrolyte and pH balance essential for homeostasis
What are the different types of renal failure?
Acute kidney injury and chronic kidney disease
What are symptoms of AKI?
Has a quick onset, potentially reversible with prompt treatment but can rapidly progress to life threatening levels if untreated
What are triggers for AKI?
Severe dehydration, blood loss, infection or nephrotoxic drugs
Over what time scale does CKD develop?
Develops gradually over years
What causes CKD?
Commonly caused by long term conditions such as diabetes and hypertension
What happens when CKD progresses?
Leads to a gradual decline in kidney function eventually needing dialysis or kidney transplantation
What is AKI?
Failure in kidney function within a 48 hour period
What are the 3 types of AKI?
Prerenal, intrarenal, postrenal
How is AKI measured on severity?
Measured in hospital based on serum creatinine and urine output as creatinine levels rise and urine output decreases with impaired kidney function
What re the high risk groups for AKI?
Underlying conditions such as trauma and shock, elderly patients
What is pre renal AKI?
Caused by decreased blood flow to the kidneys, often due to dehydration, shock or heart failure. Without adequate blood supply, the kidneys can’t filter blood effectively, leading to a decline in function. This is the most common type of AKI. As renal blood falls, the GFR decreases and the amount of substances that are filtered (sodium, potassium etc) is reduced
What is intrarenal AKI?
Results from direct damage to kidney structures such as the nephrons and blood vessels due to toxins, infection or ischemia. This type is often irreversible and requires intensive management
What is postrenal AKI?
Caused by obstructions in the urinary tract, such as kidney stones, tumors or an enlarged prostate, which prevent urine from leaving the kidneys. The build up of urine pressure can damage the nephrons and reduce kidney function
What are the 3 stages of AKI?
Mild, moderate, severe
What is acute tubular necrosis?
A common result of intrarenal AKI, this is where the tubular epithelial cells die due to a lack of oxygen or exposure to toxins
How does acute tubular necrosis impact kidney function?
Necrosis of tubular cells causes blockages within the nephron, leading to an increase in intraluminal pressure and reduced GFR. This pressure can lead to further injury and reduced kidney efficiency in filtering blood
What are the causes of acute tubular necrosis?
Ischemia, sepsis, nephrotoxic drugs or intrarenal infection
What are the main causes of post renal AKI?
Compression of the ureter or or urethra, obstruction by kidney stones
What happens due to the urine back flow in postrenaal AKI?
Increased pressure within the tubule, less of a gradient between the arteriole and the tubule, less waste moves across and GFR decreases
What are signs and symptoms of AKI?
Sudden changes in mental status or mood, nausea, vomiting, diarrhoea, rapid onset on numbness or tingling especially around hands and feet, rapid onset of hypertension, rapid decrease in urine output, muscle twitching
What is pre hospital management for AKI?
Fluids - administer slowly as per JRCALC, consider furosemide if pulmonary oedema present, convey and consider pre alert
