Renal System Flashcards
Medications to stop when a patient is in acute kidney injury: _______________________
ACE-I/ARB, NSAIDs and diuretics
NSAIDs (except if aspirin at cardiac dose e.g. 75mg od)
* Aminoglycosides
* ACE inhibitors
* Angiotensin II receptor antagonists
* Diuretics
prerenal causes of AKI
Think of what causes big problems in other major organs. In the heart, a lack of blood flow (ischaemia) to the myocardium causes a myocardial infarction. In a similar fashion, 85% of strokes are caused by ischaemia to the brain. The same goes for the kidneys. One of the major causes of AKI is ischaemia, or lack of blood flowing to the kidneys.
Examples
hypovolaemia secondary to diarrhoea/vomiting
renal artery stenosis
Renal causes of AKI
The second group of causes relate to intrinsic damage to the glomeruli, renal tubules or interstitium of the kidneys themselves. This may be due to toxins (drugs, contrast etc) or immune-mediated glomuleronephritis.
Examples
glomerulonephritis
acute tubular necrosis (ATN)
acute interstitial nephritis (AIN), respectively
rhabdomyolysis
tumour lysis syndrome
Postrenal causes of AKI
The third group relates to problems after the kidneys. This is where there is an obstruction to the urine coming from the kidneys resulting in things ‘backing-up’ and affecting the normal renal function. An example could be a unilateral ureteric stone or bilateral hydroneprosis secondary to acute urinary retention caused by benign prostatic hyperplasia.
Examples
kidney stone in ureter or bladder
benign prostatic hyperplasia
external compression of the ureter
Risk Factors of AKI
chronic kidney disease
other organ failure/chronic disease e.g. heart failure, liver disease, diabetes mellitus
history of acute kidney injury
use of drugs with nephrotoxic potential (e.g. NSAIDs, aminoglycosides, ACE inhibitors, angiotensin II receptor antagonists [ARBs] and diuretics) within the past week
use of iodinated contrast agents within the past week
age 65 years or over
oliguria (urine output less than 0.5 ml/kg/hour)
neurological or cognitive impairment or disability, which may mean limited access to fluids because of reliance on a carer
Signs and Symptoms of AKI
Many patients with early AKI may experience no symptoms. However, as renal failure progresses the following may be seen:
reduced urine output
pulmonary and peripheral oedema
arrhythmias (secondary to changes in potassium and acid-base balance)
features of uraemia (for example, pericarditis or encephalopathy)
all patients with suspected AKI should have ______
urinalysis
treatments for hyperkalaemia: Stabilisation of the cardiac membrane
Intravenous calcium gluconate
treatments for hyperkalaemia: Short-term shift in potassium from extracellular to intracellular fluid compartment
*Combined insulin/dextrose infusion
* Nebulised salbutamol
treatments for hyperkalaemia: Removal of potassium from the body
- Calcium resonium (orally or enema)
- Loop diuretics
- Dialysis
Angiotensin II receptor antagonists should be stopped in AKI as may _____________
worsen renal function
Give examples of aminoglycoside Abx
Gentamicin
____ men with raised PSA have prostate cancer
1/3
Venous bleeding compensation
Firstly, a venous bleed reduces preload, which reduces cardiac output and therefore blood pressure. This reduction in blood pressure is detected by baroreceptors, which signal a physiological compensation.
Arterial Bleed Compensation
An arterial bleed is compensated more directly by causing an instant drop in blood pressure, which is detected by baroreceptors.
Both a venous and arterial bleed will lead to increased ___________ levels and an increased ___________. However, this is a longer-term compensatory mechanism.
angiotensin II ; thirst drive
A raised PSA level can be a sign of prostate cancer. But around ___________ with a raised PSA level don’t have prostate cancer. And some men with a normal PSA level do have prostate cancer._______________ with fast-growing prostate cancer have a normal PSA level
three-quarters of men (76 percent) ; 1 in 50 men (two percent)
Machine’ - Causes of Increased Serum K+
M - Medications - ACE inhibitors, NSAIDS
A - Acidosis - Metabolic and respiratory
C - Cellular destruction - Burns, traumatic injury
H - Hypoaldosteronism, haemolysis
I - Intake - Excessive
N - Nephrons, renal failure
E - Excretion - Impaired
Prolonged diarrhoea may result in a _______ associated with ______kalaemia
metabolic acidosis ;hypo
Angiotensin II increases filtration fraction, through vasoconstriction of the ________ arteriole of the glomerulus to preserve GFR
efferent
The bladders lymphatic drainage is predominantly to the ___________________
external and internal iliac nodes
Nephrotic syndrome can cause a ___volaemic ______natraemia
hyper; hypo
The cardinal features of nephrotic syndrome are:
Oedema
Proteinuria
Hypercholesterolaemia
Hypoalbuminaemia
Alcohol bingeing can lead to ______________________ subsequently leading to polyuria
ADH suppression in the posterior pituitary gland
