Renal Flashcards
Where are the kidneys located
two kidneys located on either side of the spine at the lowest level of the rib cage
What does RRAPID stand for
Recognising and Responding to Acute Patient Illness and Deterioration
What is a nephron and how many are in the kidneys
A filtering unit
1 million in each kidney
What are the two broad functions of the kidney
Homeostasis: maintenance of the internal environment of the body
Hormone secretion: endocrine function
How does the kidney keep the balance of fluid and electrolyte
Volume status: regulates the fluid balance by urine
Electrolyte levels: sodium, potassium, urea, creatine
Osmolarity: concentration of particles exerting an somatic pressure
What are the results of small molecules being lost
Sugars: presence in urine indicates disease such as diabetes and tubular disorders
Amino acid: loss of amino acids occurs in disease of proximal tubule
What waste products and drugs are secreted by the kidneys and what can be diagnosed if levels of these are wrong
Nitrogenous waste from protein metabolism; level of creatine in blood is used to measure kidney function
Drugs: antibiotics, digoxin, opiates, lithium; drugs can accumulate in kidney disease
What are the results of chronic kidney disease
Decreased activation of Vitamin D
Decreased calcium level
Stimulates secretion of parathyroid hormone causing: secondary hyperthyroidism, release of calcium from the bone and development of bone disease known as renal osteodystrophy
What is tested in urinalysis
pH Haematuria Proteinuria Glucose Nitrites Leucocytes
What is the glomerular function rate and how is it measured
measurement of renal function
normal= 100-120 mrs/min/1.73m2
Requires the injection of a radioactive tracer of Technetium Tc99
What is creatinine clearance
Estimation of glomerular filtration rate
Creatinine is released from the muscle at a relatively constant rate
Filtered by the kidneys but some secretion into the filtrate by the proximal tubule so not as accurate and rarely used in clinical practive
What is serum creatinine
Released by muscle
Removed by kidneys
Routinely used to measure kidney function
Accumulates in kidney disease: not specific to site of injury,
delay in rise following acute kidney injury
Simple blood test:
64-104umol/L (male)
60-93 umol/L (female)
What is estimated glomerular filtration rate (eGFR) calculated using and what is it
age of patient
Sex of patient
Ethnicity
Serum creatinine
% of kidney function
What does the proximal convoluted tubule do
Recovers 70% of glomerular filtrate: water electrolytes glucose amino acids
Reabsorption of bicarbonate:
dependent upon enzyme, carbonic anhydrase
What is a loop diuretic given for
To increase urine output
What does the cortical collecting duct do
Site of reabsorption of:
Na+ in exchange for K+
Controlled by aldosterone
What does the medullary collecting duct do
Site of urinary concentration Antidiuretic hormone (ADH) acts to increase water reabsorption
What is the mechanism responsible for concentrating urine
Counter current mechanism which establishes a high conc gradient in the medulla and so enables reabsorption of water from the filtrate
What are insensible losses of fluid
sweating
faeces
respiration
What germ layer do the kidneys develop from
Intermediate mesoderm
What are the structures of the urinary system
Kidneys
Ureters
Urinary bladder
Urethra
What are the two types of genitalia of the reproductive system
Internal and external
What is the first structure of the kidneys to develop and when does this happen and how
Pronephros In week 4 Non-functional Intermediate mesoderm in the cervical region condenses and reorganises to form a number of epithelial buds It disappears around day 25
What happens in development of the mesonephric duct
In week 4
Intermediate mesoderm in the lower cervical region is induced to epithelialise forming a solid duct- mesonephric duct
Develops caudally and fuses with the walls of the cloaca on day 26
Canalisation commences from caudal end
Induces formation of mesonephric buds
Where does gonadal development happen
Medial aspect of the mesonephric ridge, forming the urogenital ridge
What happens in development of the metanephros
Starts with the formation od the ureteric buds at the caudal end of the mesonephric duct
By day 32 the ureteric buds penetrate the metanephric mesenchyme (undifferentiated mesoderm), bifurcating in a specific pattern: Renal ampulla, renal pelvis, Major calyces, Minor calyces, Collecting ducts
What is formed by each portion of the metanephros
Collecting portion: Collecting ducts Major and minor calyces Renal pelvis Ureter
Excretory portion: Bowmans capsule Proximal convoluted tubule Loop of Henle Distal convoluted tubule
How are the adult nephrons formed
Newly formed collecting tubules are covered by metanephric tissue caps
Interaction between the tubule and the cap causes: specific branching of tubule
differentiation of cells in the metanephric cap to form renal vesicles which expand to form S shaped table and bowman’s capsule which form the adult nephron
How of the kidneys relocate
Develop in the pelvic region but reside more cranially in the adult
Ascent of the kidneys is caused by growth and elongation od the developing vets
As it ascend it establishes new blood supply; lower vessels normally degenerate
In adult position by week 9
How is the bladder formed
From the urogenital sinus which is divided into 3 distinguishable parts:
Upper: presumptive urinary bladder
Pelvic: urethra
Phallic: penile urethra (males), vestibule (females)
Bladder is initially continuous with the allantois which obliterates to form the urachus that connects the apex of the bladder with the umbilicus
Which is the first functioning primitive kidney
mesonephros
What is the anatomy of the Genito-urinary system
The two kidneys are associated with the posterior abdominal wall, lateral to the aorta and IVC.
Each kidney gives off a ureter which descends alongside the vertebral column to enter the pelvis and join the bladder
A single urethra leaves the bladder and passes urine to the outside world
What are the pelvic organs and what are the characteristics
Bladder
Rectum
Uterus (female)
Project into the abdominal cavity Covered by peritoneum Form pouches where fluid collects: Vesico-rectal pouch (male) Vesico-uterine pouch and utero-rectal pouch (female)
What is acute kidney injury
Rapid reduction in kidney function
Occurs over hours to days
Rise in creatinine and decrease in urine output
What are the stages of AKI
stage 1. SCr increase >26umol/L within 48 hours or ACr increase 1.5-1.9 fold from base line
Urine output< 0.5 mL/kg/hr for 6 consecutive hours
stage 2. SCr increase 2-2.9 fold from baseline
Urine output <0.5mL/kg/hr for 12 hrs
stage 3. SCr increase >3 fold from baseline or SCr increase >354 mol/L or initiate on RRT
Urine output < 0.3 mL/kg/hr for 24 hrs or anuria for 12 hr
How does AKI present
Hypovolaemia/hypotensive Sepsis Nausea/vomiting decreased urine output Fever Diuretics Diarrhoea High stoma output Haemorrhage Burns
What are complications of AKI
Hyperkalaemia -cardiac arrest Acidaemia - vascular instability Pulmonary oedema - respiratory arrest Uraemia - pericarditis, encephalopathy gastritis malnutrition anemia
What investigations would you do for AKI and CKD
Full blood count U and Es and bicarbonate C-reactive protein Liver function tests Calcium and phosphate Immunological screen Creatine kinase Urinalysis
What are causes of chronic kidney disease
Diabetes meillitus Glomerular disease Inherited disorders such as autosomal dominant polycystic kidney disease Renal vascular disease Acute kidney injury Interstitial disease Other unknown causes
How is CKD managed
BP control: ACE inhibitors
Cholesterol control: statins
Fluid balance: loop diuretics e.g. furosemide
Anaemia: erythropoietin and ferrous sulphate
Bone metabolism: vitamin D analogues, phosphate binders, calcimimetics
Acidaemia: sodium bicarbonate
Dietary advice: decrease phosphate
What is autosomal dominant polycystic kidney disease
Presents in adult life Development of cysts on kidneys, liver, pancreas Hypertension Cardiac abnormalities Berry aneurysms
What are the treatment options of end stage kidney disease
Haemodialysis
Peritoneal dialysis
Transplantation
Conservative care
What are the indications, side effects and some examples of ACEi and how does it work
Hypertension
Cardiac failure
CKD
Hypotension
Kyperkalaemia
Ramiprill
Lisinopril
Inhibits vasoconstrictive effect of angiotensin II
What are the indications, side effects and some examples of Angiotensin receptor blockers and how does it work
Hypertension
Cardiac failure
CDK
Hypotension
Kyperkalaemia
Valsartan
Irbesartan
Inhibits vasoconstrictive effect of angiotensin II on the receptor
What are the indications and side effects of loop diuretics and how do they work
CKD
Nephrotic syndrome
Hypertension
Cardiac failure
Hypovolaemia
Hypokalaemia
Inhibits uptake of sodium, potassium, chloride and water
What are the indications, side effects of thiazides and how does it work
CKD
Nephrotic syndrome
Hypertension
Cardiac failure
Hypovolaemia
Inhibits sodium uptake
Remove sodium and water
What are the indications, side effects of spironolactone and how does it work
Cardiac failure
Liver cirrhosis
Hyperkalaemia
Inhibits aldosterone
Prevents sodium reabsorption in exchange for potassium
What are the indications, side effects of amiloride and how does it work
Prevents hypokalaemia
Hyperkalaemia
Inhibits sodium reabsorption
Removes sodium and water
What is sepsis
Life threatening organ dysfunction caused by a dysregulated host response to infection
Organ dysfunction can be represented by an increase in the sequential organ failure assessment score of >2
Which is associated with an in-hospital mortality greater than 10%
What is septic shock
A subset of sepsis
Profound circulatory, cellular and metabolic abnormalities
Greater risk of mortality than with sepsis alone
Hospital mortality rates > 40%
What are crystalloids and what are the two types
Water to which solutes have been added
High sodium containing fluids: volume resuscitation
Low sodium fluids: disperse throughout intracellular and extracellular compartments, replacement/routine maintenance
