Flashcards in Renal Deck (216)
How do the kidneys regulate acid base balance in the body?
1) Regeneration of bicarbonate in the proximal tubules
2) Removal of fixed acid such a sulphate, sulphuric acid from the blood stream
In what part of the nephron would disease be indicated if amino acids were being lost in the urine?
The level of what protein is used to measure kidney function?
Creatinine from the break down of muscle
Which 4 drugs can accumulate in kidney disease?
The kidneys produce eryhtropoeitin in response to what?
Kidneys secrete the active form of vitamin D but the first stage of producing active vitamin D occurs in what organ?
Liver secretes 25-OH-D, Kidneys convert that to calcitriol
Low blood calcium stimulates the release of what hormone which stimulates the secretion of Calcitriol from the kidneys?
How does PTH increase blood calcium?
Causes release of calcitriol from the kidneys
Causes Release of calcium and phosphorus from bone
How does calcitriol released by the kidney increase blood calcium levels?
Causes increased absorption of calcium from the small intestine
Causes release of calcium and phosphorus from bone
Why can phosphorus levels rise in CKD?
Because the kidneys act to increase excretion of phosphorus
In CKD what 3 problems may occur as a result of decreased activation of vitamin D?
1) Secondary hyperparathryoidism
2) Decreased calcium level
3) Bone disease - renal osteodystrophy
What role do the kidneys have in RAAS and how?
Secrete renin which converts angiotensinogen into angiotensin 1
3 signals activate the release if renin from the juxtaglomerular apparatus of the kidney:
1) A drop in perfusion pressure of the afferent arterioles
2) A decrease in the flux of NaCl past the macula densa
3) Activation of sympathetic nerve supply to the afferent and efferent arterioles in the kidney
Why can the haematological disease myeloma lead to CKD?
Production of an immunoglobulin which is deposited in the kidneys
Why can cardiac failure result in CKD?
Decreased blood supply to the kidneys
After what age do you begin to get a gradual decline in kidney function?
What percentage of cardiac output is received by the kidneys (and how much is this per minute)?
In urinalysis what would nitrites and leucocytes in the urine indicate?
In urinalysis what is glucose in the urine likely to indicate?
In blood tests to investigate kidney function what 6 substances would you measure the levels of?
1) Sodium 133-146 mmol/L
2) Postassium 3.5-5.3 mmol/L
3) Urea 2.5-7.5 mmol/L
4) Creatinine 64-104 umol/L
(Above 4 are part of urea and electrolytes)
5) Bicarbonate 22-29 mmol/L
6) Chloride 95-108 mmol/L
What 6 things are you likely to be testing for in urinalysis to investigate kidney disease?
2) pH varies
When measuring urine what would you measure the protein in reference to?
Protein/Creatinine ratio ( 0.1-13 mg/mmol/L)
When would a midstream urine sample be required?
If infection was suspected
What 4 radiological investigations could be carried out on the kidneys and what would each identify?
1) Abdominal x-ray - may identify calcification
2) Renal tract ultrasound - Assesses the size of the kidneys and bladder and identifies any obstruction
3) CT KUB (Kidneys, ureter, bladder) - Calcification use with iodinated contrast
4) Magnetic resonance angiography (MRA) - Blood supply
What may a kidney biopsy be required to diagnose and under what guidance is it performed?
Required to diagnose AKI
Performed under ultrasound guidance
What is the length of a healthy kidney?
What is a nephron made up of?
Glomerulus surrounded by Bowman's capsule
Enveloped by a vascular network
Where do 80% of the kidney glomeruli lie?
In the cortex
How much urine does a healthy person produce in one day?
What are the 4 parts of the renal tubule?
Proximal convoluted tubule
Distal convoluted tubule
Loop of Henle
What pressures contribute to movement of filtrate out of the glomerulus and into the glomerulus?
Out - hydrostatic pressure of capillary
In - Plasma protein oncotic pressure
What is another name for an epithelial foot process?
What is pyelonephritis?
Pus in the kidney
What is reflux nephropathy and why does it occur and what can it lead to?
Occurs in childhood when the kidneys are growing
Have an incompetent vesicoureteric junction
On voiding urine passes back up ureter then back into bladder, there is risk of stagnation and infection
On voiding infected urine passes back up to the kidneys - pyelonephritis - injury and scarring
Can lead to CKD
What is the clinical presentation of reflux nephropathy and what is the treatment?
Child with fever of unknown origin
Fails to meet developmental mile stones - bedwetting at 5-7 years
Family history of reflux nephropathy
Treatment is prophylactic Abx
If haematuria was found in a patient over 45 what would you suspect and who would you refer them to?
Suspect a lesion somewhere in the renal tract
Refer to a urologist
If haematuria was found in a patient under 45 what would you suspect and who would you refer them to?
refer to the renal physician
What is glomerulonephritis?
Inflammation in the glomerulus
What 4 things make up nephrotic syndrome?
What happens in nephrotic syndrome to the glomerulus?
Injury to the foot processes of the nephron
What 4 things can cause injury to the foot processes of the nephron and therefore nephrotic syndrome?
1) Minimal change disease (children)
2) Membranous nephropathy
3) Focal segmented glomerulosclerosis
4) Amyloid (caused by myeloma, malignancy of the bone marrow)
What is the most important way by which foot processes in health prevent the filtration of albumin from the blood?
Repel them by being negatively charged
What 4 important substances are freely filtered into the nephron?
3) Amino acids
What 3 things affect the filtration of a molecule across the glomerular basement membrane?
1) Molecular weight
2) Surface charge - glomerular basement membrane is negatively charged
3) Hydrostatic pressure in the afferent arteriole
What is a normal glomerular filtration rate?
What does accurate glomerular filtration rate measurement require the injection of and when is this carried out?
The injection of a radioactive tracer such as Technetium Tc99
Performed rarely except in the case of live kidney donors to determine accurate kidney function prior to donation
What is performed as an alternative to glomerular filtration rate but is not used often clinically? Is this more or less accurate?
Not as accurate
Requires a blood test and 24 hour urine collection
What is the routinely used measurement of kidney function?
Simple blood test
Normal range is 64-104 umol/L
What 4 things are required to calculate eGFR?
1) Serum creatinine
What does eGFR correlate with?
Percentage kidney function
At what eGFR do patients need to commence dialysis?
At what level is plasma osmolality maintained at to maintain normal cellular function?
What is a normal urine osmolality?
What mechanism is responsible for the kidneys ability to produce concentrated urine during periods of decreased fluid intake?
Counter current mechanism
Establishes a high conc gradient in the medulla and enables water resorption in the proximal tubule and the collecting duct
What are the 3 methods of insensible loss of fluid?
How does antidiuretic hormone increase fluid retention?
Inserts channels into the medullary collecting duct to allow reabsorption of water
What 2 things can uraemia (accumulation of waste products) lead to?
Where is the Na+/K+ATPase in the nephron?
In all sections of the nephron
Located on the apical (blood) side
Pumps 3Na+ out for 2 K+ in
What percentage of glomerular filtrate is recovered at the proximal convoluted tubule?
70% (water and electrolytes)
At what point in the nephron is bicarbonate regenerated?
Proximal convoluted tubule
What channels are present in the proximal convoluted tubule to enable reabsorption of large amounts of water?
What enzyme is bicarbonate regeneration in the proximal convoluted tubule dependent on and what drug inhibits this enzyme?
Inhibited by acetazolamide
Why do you get acidaemia in kidney disease and how may you compensate for this?
Failure to regenerate bicarbonate
Respiratory compensation - tachypnoea to blow off CO2
How does carbonic anhydrase help in the regeneration of bicarbonate?
For bicarbonate to pass into the podocyte from the filtrate it must be neutral
In filtrate converted to H20 and CO2 so it can pass through the podocyte membrane
When in the cell carbonic anhydrase converts CO2 + H2O back to bicarbonate
How is Na+, K+, Cl- and H2O absorbed in the ascending limb of Henle?
Through a K+,2Cl-, Na+ co transporter using the Na+ gradient set up by Na+/K+ATPase and water then follows
Where is the site of action of loop diuretics such a furosemide, what could this lead to the development of?
Act on the K+,2Cl-,Na+ co transporter in the ascending limb of Henle
Could lead to the development of hyponutraemia
What is reabsorbed at the cortical collecting duct and how?
Na+ (with Cl-, H20) is reabsorbed in exchange for K+
This is controlled by aldosterone
How do potassium sparing diuretics such as spironalactone work and what do they increase the riskl of?
Block the absorption of Na+ in exchange for K+
High risk of hyperkalaemia
What is diabetes insipidus and what can it cause?
Central failure to secrete ADH
or a peripheral resistance to ADH
Large volume of water output - polyuria
What 2 things can hyponatraemia lead to?
Confusion and fits
What are the 3 types of AKI?
Pre renal AKI, Intrinsic AKI, Post renal AKI
Over what time period would a reduction in kidney function be considered AKI rather than CKD?
Abrupt reduction in kidney function occurring over hours to weeks
With a SCr increase of >26umol/L or SCr increase >1.5 to 1.9 fold from baseline what stage AKI is this?
With a SCr increase of >3 fold from baseline or >354 umol/L what stage AKI would this be?
With a SCr increase of >2-2.9 fold from baseline what stage kidney disease would this be?
If a patient commenced on renal replacement therapy what stage AKI would this be?
If a patient produced 6 consecutive hours what stage kidney disease would this be considered to be?
If a patient produced 12 hours what stage kidney disease would this be?
If a patient produced 24 hours or was anuric for 12 hours what stage kidney disease would this be considered to be?
What does pre renal AKI refer to?
AKI due to inadequate blood flow to perfuse the kidneys
What are the causes of pre renal AKI? 5
2) Severe sepsis (vasodilation)
3)Vomiting and diarrhoea
4) Over diuresis with diuretics
5) Burns (excessive fluid loss through the skin)
What does intrinsic AKI refer to?
Intrinsic renal disease where there is structural damage to the renal tissue (glomeruli/tubules/interstitium) - most intrinsic AKI cause blood and our protein to leak out through the kidney which can be detected using a urine dipstick
What are some causes of intrinsic AKI? 5
1) Nephrotoxic medication
2) Interstitial nephritis
5) Tubulo nephritis
Name 4 nephrotoxic drugs/ substances?
2) Contrast media
What does post renal AKI refer to?
Post renal AKI is caused by obstruction to the renal tract, this can be anywhere from the renal pelvis to the urethra
What 8 things could cause post renal AKI?
1) Retroperitoneal fibrosis
2) Renal stone disease
3) Bladder carcinoma
4) Prostatic enlargement
5) Cervical carcinoma
6) Intra Abdominal hypertension
7) Urethral stricture
8) Obstructed urinary catheter
What is hydronephrosis?
Large kidneys on ultrasound
What 3 features may first present in AKI?
1) Symptoms suggesting uraemia
2) Raised serum creatinine
3) Decreased urine output
What are the risk factors for AKI? 9
1) Age >75
3) Cardiac failure (decreased renal perfusion)
4) Atherosclerotic peripheral vascular disease
5) Liver disease (hepato renal failure)
6) DM (diabetic nephropathy)
7) Nephrotoxic medications (NSAIDs, ACE-I, ARBs Gentamicin)
8) Sepsis (vasodilation - reduced perfusion pressure)
9) Hypovolaemia (eg. vomiting/diarrhoea lose water and reduce volume of blood)
Why may prostatic disease lead to AKI?
Post renal AKI, compressing the urethra
What are the 3 systemic clinical features of AKI?
1) Fever (vasculitis)
2) Rash (vasculitis)
3) Joint pains (vasculitis)
What 3 things should a general clinical examination for AKI include?
1) Rash (vasculitis)
2) Uveitis (inflammed pigmented part of the eye)
3) Joint swelling (vasculitis)
What is the risk for hypokalaemia?
May lead to life threatening arrhythmias
What 6 things would you measure in an assessmant of core volume status?
1) Core temperature (fever-increased fluid loss)
2) Peripheral perfusion (cold and clammy - hypotension)
3) Axillae (present or absence of sweat)
4) Heart rate (tachychardia - fever, haemorrhage)
5) Blood pressure (hypotension)
6) JVP (barometer of intravascular volume)
What 2 clinical signs would indicate reno-vascular disease?
1) Audible bruits
2) Impalpable peripheral pulses
Why may you palpate the lower abdomen in an examination to assess AKI?
To see if the bladder is palpable as this would indicate obstruction and thus post renal AKI
What 3 baseline lab investigations would you send off in suspected AKI and what 2 extras would you send off if infection was suspected?
4) Urine culture (if infection is suspected)
5) Blood culture (if infection is suspected)
Name 2 viruses which can potentially cause renal disease and you would send virology lab tests for?
1) Hep B/C serology
What are the majority of cases of AKI caused by?
Intrinsic secondary to pre renal or intrinsic secondary to sepsis and hypotension
What is the treatment for intrinsic AKI secondary to sepsis/ hypotension? 3
1) Adequate volume replacement - IV fluids
2) Treatment of underlying medical condition (eg. sepsis, haemorrhage)
3) Avoidance of nephrotoxic medications
What therapy is required in lupus nephritis?
What 3 pharmacokinetic properties are altered in renal failure in the acutely ill patient and therefore drug doses need to be altered appropriately?
1) Volume of distribution
3) Protein binding
Why may pulmonary oedema occur in AKI?
Retention of fluids as kidneys not filtering them out
What 3 things may uraemia lead to?
2) Neuropathy - dysfunction of peripheral nerves
3) Encephalopathy - disease in which the function of the brain is affected
What is GFR measured in?
How many stages of CKD are there?
5 with 3 being divided into 3a and 3b
What is the GFR in stage 1 CKD and what is your kidney function like?
>90 normal kidney function but urine abnormalities and structural abnormalities point to kidney disease
What is the GFR in stage 2 CKD and what is the renal function like?
60-90 mildly reduced kidney function but urine abnormalities and structural abnormalities point to kidney disease
What is the GFR in Stage 3a CKD and what is your kidney function like?
45-59 moderately reduced kidney function
What is the GFR in Stage 3b CKD and what is your kidney function like?
30-44 moderately reduced kidney function
What is the GFR in Stage 4 kidney disease and what is your kidney function like?
15-29 severely reduced kidney function
What is the most common cause of end stage kidney disease?
Name an inherited disease which can lead to CKD?
Autosomal polycystic kidney disease
Name a 1 primary and 2 secondary glomerular diseases which can lead to CKD?
Primary - membranous nephropathy
Secondary - Diabetes and lupus nephritis
Name a vascular disease which can lead to CKD?
What can cause tubulo interstitial disease which can cause CKD?
Name 2 things that cause renal tract obstruction which can cause CKD?
Renal stone disease
What are the 10 broad categories of signs and symptoms of CKD?
1) CNS effects
3) Platelet abnormalities
4) CVS effects
5) Skin symptoms
6) Renal symptoms
7) GI symptoms
8) Endocrine glands/gonads symptoms
10) Renal osteodystophy
What are the 4 GI tract symptoms in CKD?
What are the 3 endocrine/gonadal symptoms in CKD?
3) Erectile dysfunction
What is paraesthesia and why might it occur in CKD?
Pins and needles
What are the 6 symptoms associated with renal osteodystrophy in CKD and why do they occur?
Lack of calcium and phosphate problems
2) Muscle weakness
3) Bone pain
6) Adynamic bone disease
Why might you get oedema in CKD?
Heart failure is a CV symptom of CKD and you also get salt and water retention as a renal symptoms of CKD so these 2 together contribute to oedema
What are the 2 symptoms you may see in the skin in CKD and why?
Puritis - phosphate deposited in the skin causes itching - poorly functioning kidneys dont remove phosphate well
What are the 2 symptoms associated with platelet abnormalities in CKD and why do they occur?
High urea (not excreted by the poorly functioning kidneys) interferes with platelet function
Get epistaxis (nose bleeds)
What are the 3 CNS symptoms in CKD and what are they due to?
Uraemia and hyponatraemia
Why does anaemia occur in CKD?
In response to hypoxia kidneys normally secrete erythropoietin which leads to the formation of RBCs
Poorly functioning kidney doesnt do this
What are the 4 CV symptoms in CKD and why do they occur?
1) Uraemic pericarditis
2) Hypertension (RAAS system knocked off?)
3) Peripheral vascular disease
4) Heart failure
Why might you get bone pain in CKD?
Bone disease - resorption of calcium from bone due to poor calcium absorption due to lack of active vitamin D from the kidneys
What are the 3 renal symptoms in CKD?
3) Salt and water retention
What are the 4 features of nephritic syndrome?
2) Proteinuria (non nephrotic)
Why would you do urinalysis investigations in CKD?
To look for blood or protein suggestive of glomerular disease
What 4 substances would you look for in the blood in suspected CKD?
1) Elevated urea
2) Elevated creatinine
3) Hypocalcaemia (indicative of CKD as opposed to AKI)
4) Hyperphosphataemia (again indicative of CKD as opposed to AKI)
Why would you perform immunology in CKD?
Look for immunoglobulins, do serum electrophoresis and look for Bence Jones protein)
What radiology would you perform in CKD?
Renal ultrasound scan to rule out obstruction
What is the BP target for CKD patients (compared to healthy patients) and why?
CKD - 130/80 mmHg
Healthy - 140/90mmHg
High BP over time will damage the kidneys
Kidney disease also leads to hypertension
CKD patients are a high risk group for CV disease and mortality
In CKD how is hyperkalaemia treated?
Reduced dietary intake
How is acidosis treated in CKD?
Sodium Bicarbonate tablets
How is metabollic bone disease treated in CKD (2 things)?
1) Phosphate binders - prevent it being absorbed in the gut allowing it to be excreted
2) Vit D tablets (containing active Vit D)
How is anaemia in CKD treated?
Subcutaneous Recombinant erythropoeitin
What are the 2 options for patients with ESKD?
1) Renal replacement therapy
2) Conservative therpay
What 4 things are included in renal replacement therapy?
2) Peritoneal dialysis
4) Renal transplantation
What is the national GFR for commencing dialysis?
How does peritoneal dialysis work?
Peritoneum is used as a semipermeable membrane
Tube placed directly into the peritoneal cavity and dialysis fluid is run into the peritoneal cavity
Uraemic toxins pass into the peritoneal fluid down a concentration gradient and water is dragged by osmosis into the peritoneal cavity (most dialysis fluids contain glucose to create this osmotic gradient)
What is the main benefit of peritoneal dialysis?
Can do it at home
What are the 2 possible complications of peritoneal dialysis?
What are the 4 contraindications for peritoneal dialysis?
1) Presence of a hernia
2) Abdominal hernias
3) Severe arthritis - unable to perform technique
4) Previous surgery with adhesions
How does haemodialysis work?
Blood pumped through an artificial kidney (layers of semipermeable membrane known as a dialyser) with dialysis fluid flowing in the opposite direction
Uraemic toxins pass across the membrane by diffusion and water can be removed from the blood
Haemodialysis requires a blood flow of at least 200 ml per minute through the dialyser what are the 2 possible forms of vascular access?
1) An arterovenous fistula
2) Large bore double lumen cannula (can be used in an emergency
What are the benefits of haemodialysis?
Is hospital based for elderly patients
What are the possible complications of haemodialysis?
2) Infections of vascular access
3) Time consuming
What is the contraindication of haemodialysis?
Severe cardiac failure
Why will patients with a kidney transplant need to take long term immunosuppressants?
To prevent there body rejecting the kidney
What are the 4 possible complications of kidney transplantation?
1) Infections (immunosuppression)
2) Malignancy (immunosuppression)
4) Recurrent kidney disease
What is the contra indication of kidney transplant?
Co-morbidities making the operation too risky
What are the 2 types of donor?
What are the 2 types of deceased donors?
1) Donation after brain stem death
2) Donation after circulatory death
What is haemofiltration and when is it used?
For patients requiring renal replacement therapy on the ICU who are provided with continuous renal support
Works in a similar way to haemodialysis but is much more gentle treatment
Important for patients who are acutely unwell and have cardiac instability who would not tolerate normal haemodialysis
What does A stand for in RRAPID and what would you look listen and feel for?
A = airways
Look - chest movements, accessory muscles use, foreign body obstruction, misting of oxygen mask
Listen - abnormal or absent breath soundsa
Feel - airflow on inspiration and expirations
If somewhere has abnormal airways what would your response be?
1) Call for help
2) Give them oxygen
3) Jaw thrust, head tilt/chin lift
4) Remove obvious foreign bodies
6) Airway adjuncts
What does B stand for in RRAPID and what would you look listen and feel for?
B =. breathing
Look - respiratory rate, depth and symmetry, accessory muscle use, sweating/cyanosis, ability to clear secretions by coughing
Listen - ability to talk in complete sentences, coughing/noisy breathing, percussion, chest auscultation
Feel - tracheal deviation, chest expansion, percussion note, surgical emphysema (rice crispies)
What is the response to abnormal B in RRAPID?
1) Sit the patient up
2) Give O2
3) Treat underlying cause
What does C stand for in RRAPID and what would you assess to assess the patients status in this? 8
C = circulation
1) Pulse rate and character
2) Cap refill time (
What would be the response to abnormal C in RRAPID? 3
1) Treat the underlying problem
2) Blood tests / ECG
3) Fluid challenge
What does the D stand for in RRAPID?
What is AVPU and what part of RRAPID is it used to assess?
A - alert
V - responds to a Verbal stimulus
P - responds only to Pain
U - Unresponsive to any stimulus
Use is to assess disability in RRAPID
Other than AVPU, what other 2 things would you use to assess disability in RRAPID?
1) Pupils - size/reactive to light
2) Capillary blood glucose level
What 3 things may be your response to disability in RRAPID?
1) Protect airway if needed
2) Give glucose is hypoglycaemia
3) Treat seizure activity
What is E in RRAPID and what does it involve?
top to toe examination
adequate exposure - to see rashes or swelling
Prevent cold/preserve dignity
What would be the response to abnormal exposure in RRAPID?
1) Senior medical advices
2) Further management plan
3) Involve critical care outreach team
What is the minimum frequency of NEWS assesment if NEWSing at 0?
What are the parts of the SBARR tool?
Rhabdomyolysis can lead to what kind of AKI?
Snake bites can cause what kind of AKI?
What kind of AKI would MI lead to?
Pre renal AKI (hypotension)
What is rhabdomyolisis?
Breakdown of muscle releasing myoglobin and myoglobin is toxic to the kidney
Why might you measure the serum creatine kinase in AKI?
To test for rhabdomyolysis
What are the 6 complications of AKI?
3) Pulmonary oedema
5) GI symptoms
6) Haematological (anaemia/bleeding)
What does the acronym STOP stand for in management of AKI?
Sepsis - treat promptly
Toxins - stop any nephrotoxic drugs
Optimise BP - consider fluids, hold antihypertensive drugs, consider vasopressors
Prevent harm - review medication
What does hyperkalaemia do to an ECG?
Results in tented T waves
How is pulmonary oedema treated in AKI?
High flow O2
High dose furosemide
When would renal replacement therapy be indicated in AKI?
increasing hyperkalaemia unresponsive to medical therapy
Pulmonary oedema unresponsive to medical therapy
Severe acidosis pH
What other features tend to present with diabetic nephropathy?
How is glomerular disease mediated?
What 4 things can glomerular disease present as?
1) Nephrotic syndrome
2) Asymptomatic haematuria/proteinuria
3) Nephritic syndrome
4) Rapidly progressive glomerulonephritis
What is IgA nephropathy?
Deposition of IgA in glomerulus causing glomerular disease
What is the likely type of glomerular disease in a child with throat infection, swollen ankles and hypotension?
Post streptococcal glomerular nephritis
A patient with joint pains, rashes and red eyes is likely to have what kind of glomerular disease?
Rapidly progressive glomerular nephritis
Why may a patient with CKD be given statins?
At increased risk of CV problems
How do calcimimetics given to patient with CKD help treat bone disease?
Inhibit parathyroid secretion
Other than hygrogen and bicarbonate reabsorption how else does the kidney buffer the blood?
Conversion of ammonia to ammonium in the urine (extra H+ leaves with it)
What is the normal pH range and when would it be considered dangerously high or low?
What is the Schwartz Barter approach to acid-base diseases based on?
Bonsted lowry definition of acids and bases
Sees hydrogen ion concentration as a function of the ratio between the PCO2 and the serum bicarbonate
What is the Stewart approach to acid base imbalance also termed and what is it based on?
Termed the strong ion difference
Based on the principal that serum bicarbonate does not alter blood pH
How is the anion gap calculated and what is its normal range?
[Na+] - ([HCO3-] + [Cl-])
What does an increase or a decrease in anion gap indicate?
Increase = acidosis
Decrease = alkalosis
What does the MUDPALES acronym stand for in the high anion gap acidosis disease?
Methanol - Drug toxicity
Uraemia - CKD, AKI
Diabetes - ketoacidosis
Paraldehyde - Drug toxicity
Alcohol - drug toxicity
Lactate - Lactic acidosis from liver failure or tissue hypoxia
Ethelyne glycol - drug toxicity
Salicylate (aspirin) - drug toxicity
What is the osmolal gap and in what kind of high anion gap metabollic acidosis would you get an elevated osmolal gap?
In ethylene glycol toxicity
Osmolal gap = difference between serum osmolality and calculated osmolality
Calculated osmolality = 2 x [Na] + glucose + urea
What would calcium oxalate crystals in the urine and an osmolal gap of > 25mOsm/kg indicate?
Ethylene glycol toxicity
What is the treatment for ethylene glycol toxicity?
Alcohol/ Formepizole infusion - inhibit alcohol dehydrogenase (as ethylene glycol is metabollised to glycolate which is toxic to the tissues)
What are the 3 main causes of normal anion gap metabollic acidosis (hyperchloraemic)?
1) GI HCO3- loss
2) Renal HCO3- loss (renal tubular acidosis, atezolamide)
3) Infusion of 0.9% saline
What is the general treatment for acid base disorders in the acutely ill patient?
1) Correct fluid and electrolyte balance
2) Correct underlying cause for acid-base disorder
3) specific therapy to correct HCO3- or PCO2
Where does angiotensin II act on the kidney?
Causes vasoconstriction in the efferent arteriole to increase transglomerular pressure and therefore GFR
What are the 2 main effects of angiotensin II?
2) Release of aldosterone from the adrenal cortex
How do Beta blockers act on the RAAS?
Inhibit the sympathetic tone influence on Renin release
How do renin inhibitors act on the RAAS?
Prevent Conversion of angiotensinogen to angiotensin 1
How do ACEi work on the RAAS?
Prevent the conversion of angiotensin 1 to angiotensin 2 in the lungs
How do ARBs work on the RAAS?
Prevent Ang 2 causing release of aldosterone and vasoconstriction
Ramipril and Lisonopril are examples of what kind of drug?
What are the indications of ACEis and ARBs?
hat are the 2 possible side effects of ACEi and ARBs?
2) Hyperkalaemia (prevents the action of aldosterone)
What kind of drugs are Valsartan and Irbestran?
Where do loop diuretics act and what do they do?
Act on the loop of Henle
Prevent uptake of Na, K, Cl and H2O
What are the indications of loop diuretics?
2) Nephrotic syndrome
4) Cardiac failure
What are the side effects of loop diuretics?
What is stage 5D CKD?>
Patients on dialysis