L21*-Kidney injury Flashcards
(22 cards)
Name few functions of the kidneys relating to homeostasis.
-Elimination of waste
-Water homeostasis
– Electrolyte homeostasis
– Acid base homeostasis
– Blood pressure control
What are the 2 types of kidney failures or injuries ?
- Chronic kidney disease - develop gradually and persist over time, long-term complications.
-usually slowly progressive and irreversible.
Commonly due to diabetes and/or
hypertension but also multiple other causes. - Acute kidney injury - happen suddenly and may be severe. can resolve quickly with treatment.
-usually rapid onset (hrs to dsys) and usually due to combination of systemic illness plus multiple risk factors and medication.
-usually reversible with treatment.
Name few functions of the kidney relating to Metabolic/Endocrine activity.
– synthesis of hormones
Vitamin D
Erythropoietin
Renin
– Excretion of drugs and
drug metabolites
What are some common conditions(ie:hypertension) that can develop to acute kidney injury ?
-older age
-diabetes mellitus
-hypertension
-heart disease
-chronic kidney disease
What happens if salt and water homeostasis fails ?
-Inability to concentrate urine (early)
– Loss of diurnal rhythm of urine
excretion
-more dilute urine 😔
- Inability to excrete water load
– Oedema(movement of fluid out of the vasculature and into other tissues bc low oncotic pressure in the plasma) when the [albumin] is full. - Sodium retention leads to high blood pressure
– Hypertension
– CNS dysfunction (low or high Na)
Why are NSAIDs are bad for the kidney ?
Reduced Blood Flow – NSAIDs block prostaglandins, which help maintain blood flow to the kidneys. Without enough blood supply, kidney function can decline.
Fluid Retention & High Blood Pressure – These medications can cause the body to retain fluid and increase blood pressure, putting extra strain on the kidneys.
Risk of Acute Kidney Injury (AKI) – High doses or prolonged use of NSAIDs can lead to sudden kidney damage, especially in people with existing kidney issues.
Direct Toxic Effects – NSAIDs may cause inflammation or damage to kidney tissues, leading to conditions like acute tubular necrosis or interstitial nephritis
Kidney regulates the K+ levels too? what happens to K+ levels in a kidney injury ?
-severe hyperkalaemia when GFR<10ml/min
-alterations in the membrane excitabilty.
-cardiac arrythmias -
How can the body be more acidic or cause systemic acidosis ?
If the kidney fails to excrete the acid or H+ in the reaction with bicarbonate ions.
What does it mean when the body undergoes systemic acidosis ?
-symptoms of breathlessness (dyspnoea)
-physiological systems start to fail > enzyme function depends on correct pH.
-cardiac muscle contraction is reduced.
-acidosis drives hyperkalaemia.
Kidneys also make EPO-Erythropoietin which drives the red cell production. What happens to these when the kidney is injured ?
Anaemia - low RBC count
– Impaired quality of life
– reduced exercise capacity
– impaired cognition
– Transfusion requirement
– Iron overload - boost iron absorption from food to make more RBC and overtime these can accumulate.
– Blood-borne infection
– ↑ risk of Left Ventricular Hypertrophy
– ↑ CV disease in patients with CKD
-synthetic EPO - better treatment -athletics use it 😡 to cheat.
What happens if metabolic waste products are not excreted ?
Accumulation of toxic waste products
– creatinine rises only after significant renal damage.
– retention nitrogenous waste
If severe causes confusion and heart
problems
– retention of urate
Causing gout(joint problems)
– retention of phosphate
Cardiovascular disease
Many drugs are excreted through kidney and what causes the build up of drugs in a kidney injury ? Name few drugs that do that.
-Build up of high concentrations of drugs in the body can lead to increased risk of toxicity.
Name range of effects or complications of if we loose our kidneys.
Anaemia
Hypertension
Disturbed calcium/phosphate homeostasis
Cardiovascular disease
Bone disease
Abnormal handling of drugs
Immune suppression
Bleeding tendency
Complications of treatment
What is Renal replacement therapy ?
therapy used in both Acute or Chronic Kidney Disease.
👇
If the person is unable to maintain:
– Water homeostasis
– Electrolyte homeostasis
– Acid/base homeostasis
– Excrete metabolic waste products
Without treatment this is a terminal illness
Name few other treatments for Kidney injury.
- Dialysis
– Peritoneal dialysis
– Haemodialysis - Transplantation from a living donor or someone 💀
- Conservative care (palliative care)- from someone who 💀 when they are aware bc of their choice.
- Transplantation replaces all kidney
functions.
What is dialysis and what does it do ?
-is an extracorporeal therapy where fluids and solutes are removed or added to the patients blood.
-done by separating the patients blood and dialysis fluid with a semi-permeable membrane.
Dialysis do:-
– Water homeostasis
– Electrolyte homeostasis
– Acid/base homeostasis
– Excrete metabolic waste products
Explain Haemodialysis
-Blood is taken out of the body(artery) and passed through a dialysis filter. Then that blood passes in the opposite direction in the dialysing filter. Two direction flows are separated by a semi-permeable membrane.
-Needs permanent access to the circulation:-
AV fistula
central venous catheter.
-can last indefinitely
Explain Peritoneal dialysis
-Fluid is pumped into the abdominal cavity
- Blood is separated from the fluid within the peritoneal cavity by a peritoneal membrane.
- Peritoneal membrane lines all of the internal organs which is a semi-permeable membrane.
- Peritoneal dialysis fluid contains water molecules, dextrin, urea, nitrogen containing compounds and sugar molecules to keep the osmotic pressure high.
- High osmotic pressure is aided with water movement.
- There is also some , Na+, K+ found at average or lower level is to aid the chemical gradient. So Na+ can diffuse down the diffusion gradient and enter the peritoneal cavity.
- There is also bicarbonate ions to adjust the pH.
Kidney transplant is given to who?
-Patients with CKD-chronic kidney disease 5
Unless an absolute contraindication
Absolute contraindications
– High peri-operative mortality
– Poor life expectancy
– Active malignancy
Age is not an absolute contraindication
Relative contraindications
– Coronary or cerebrovascular disease
– Recurrent disease
Name few Immunosuppressants given for kidney transplant to stop the immune system rejecting the new kidney.
- Steroids
– Calcineurin inhibitors
– Azathioprine
– Mycophenolate
Write a simple method as to how the transplant is done and what are the pros 😊 from it ?
has to connected to arterial supply, venous supply and the ureter to the bladder so the urine will flow from the newly transplanted kidney into the bladder.
😊:-
-better life expectancy
-better quality of life
replaces ALL renal functions
Where do kidneys come from ?
- Cadaveric donor
– Brain-stem dead donors- from patients who are brain dead but their circulatory system still working.
– Non- heart beating donors
need to be assessed within 30 min of death
Need to presume consent - Living donor (aiming for 30% of transplants)
– must ensure assess donor very carefully
(Hippocrates oath to do no harm)
– Most likely source to increase available organs
