General Questions Flashcards
What is respiratory acidosis?
Respiratory acidosis is a condition that occurs when the lungs cannot remove all of the carbon dioxide the body produces. This causes body fluids, especially the blood, to become too acidic.
What is Oliguria?
Reduced output of urine
What does MUST stand for?
Malnutrition universal screening tool
What is Bradykinin and what is it’s effect on blood vessels?
An inflammatory mediator
Causes dilation of BV’s
What is a pyelogram?
X-Ray imagine of urinary system, gathered of a radiopaque dye has been administered IV
When having a PSA test the patient must not have…?
Ejaculated in last 48hrs
Exercised rigorously in last 48hrs
Undergone DRE in last week
Have an active UTI
Define hypertrophy and hyperplasia:
Hypertrophy: Growth without increased cell numbers
Hyperplasia: Growth with increased cell numbers
The prostate secretes roughly what percentage of seminal fluid?
25%
What is the Gold standard best test to look at the bladder?
Cystoscopy
When would diffusion weighted imaging be used?
To see liquids
What type of tumour carries an increased risk of development with multiple head CT scans?
Meningioma
How long after contrast is injected are scans taken and why?
70 seconds
To maximise amount in kidney and ureter
What contrast medium is used for a cystogram and why?
Iodine as it is safe if it leaks into tissues (unlike barium)
What is fluroscopy?
Continues low dose x-rays are used to give real time view
Paediatrics uses more of what two types of scans?
Ultrasound and MRI
NB ultrasound is very operator dependant
What is a KUB radiograph?
Kidney, ureter, bladder
Very large kidney stones with irregular appearances are known as what?
Staghorn kidney stones
Name 4 risk factors for kidney stones?
Hyperthyroidism, obesity, personal/ fam history, dehydration
Why do patients with renal failure often hyperventilate?
To give respiratory compensation (blow off CO2) for the metabolic acidosis caused by leaking of bicarbonate from the kidney
Why is PCO2 decreased in patients with renal failure?
To give respiratory compensation (blow off CO2) for the metabolic acidosis caused by leaking of bicarbonate from the kidney
Why is cloudy urine seen in patients with renal failure?
Leak of proteins from the kidney into the urine
Why is Hb levels decreased in patients with kidney failure?
EPO is produced by the kidney
How is a DRE performed?
Use lubricated index finger, insert and turn finger 180degrees
UT obstruction increases susceptibility to X and Y. Unrelieved obstruction almost always leads to Z
X+Y= UTI and stone formation Z= Hydronephrosis (perm renal atrophy)
What it diuresis?
Increased or excessive production of urine
What is the most common cancer of the bladder?
TCC- Transitional cell carcinoma
SCC if risk factors such as chronic infection of inflammation
What are the three common sites of renal calculi in the ureters?
1- Uretopelvic junction
2- Pelvic inlet
3- Entrance to bladder (vesicoureteric junction)
What happens to potassium levels when there is renal damage?
P gets hyperkalaemia
As K+ is actively transported out into DCT by the kidney (so impaired kidney function means less K+ in DCT so more is retained)
What happens to urine sodium levels when there is renal impairment?
Decreased levels!
Na+ normally reabsorbed with H+/Na+ antiporter
P likely has acidosis (so raised H+ in serum) so this means they pull more H+ into urine therefore more Na+ out of urine (Also a decreased GFR means less kidney function and transport of Na)
What type of bacteria are most commonly responsible for UTI’s?
Gram negative
GI tract comes from which embryological layer?
Endoderm
Name the structures of the foregut?
Esophagus, stomach, upper duodenum, pancreas, gall bladder, liver, spleen
What are the structures of the midgut?
Lower duodeni, jejunum, ileum, cecum (plus iliocecal valve), ascending colon, and 2/3rd of the transverse colon
What are the structures of the hindgut?
Distal 1/3 of transverse colon, descending colon, sigmoid colon and rectum
What are the three name types of pain you can get? What are their characteristics?
Visceral- Often dull pain, poorly localized
Parietal- Sharp, well localized
Referred-
How is visceral pain described? What type of fibers carry it?
Poorly localized (due to poor receptor distribution)
Dull pain
Done by unmyelinated C-fibes (slower transmission and high threshold- so need big stimulus to elicit)
Where are pain receptors often found in viscera ?
In the capsule of the organ
What type of fibers carry parietal pain?
Myelinated alpha-fibers
So fast, with a lower threshold also
Where is referred pain from viscera felt?
In the dermatomes at the spinal level which the supply to that organ synapses
What are the two types of referred pain?
1- Somatic referral (to dermatome of the visceral nerves)
2- Where distant area affected because nerve which supplies that area damaged or affected
What is the definition of metabolic acidosis?
Blood pH less than 7.35
Plasma bicarbonate less than 22mmol/L
ERCP is used to do what?
Diagnose and treat problems of the pancreatic/ biliary ducts (e.g. gall stones)
What are the three phases of the stress response?
Alarm- Fight or flight response
Resistance- (if >a few hrs). Dominated by cortisol
Exhaustion- When resistance phase can no longer be maintained
Pain from the viscera is transmitted by which fibres? What sort of pain to these fibres transmit?
C-Fibres. Poorly localised pain
What is the difference between visceral and parietal pain in regards to presentation and nerves involved?
Visceral: Poorly localised/ pain to whole dermatome/ travels along nerve from organ- C fibre
Parietal: Sharp and well localised/ travels along same nerve as abdo wall
How long does it take for the stomach to empty/ chyme to traverse the SI/ LI
Stomach emptying: 3-5hrs
SI transit: 2-4hrs
LI transit: 8-60 hours
Which nutrients are easiest to digest?
Carbs > proteins > lipids
Where is thirst regulated in the brain?
Hypothalamus measures osmolarity
Chemo/baroreceptors measure pressue
High osmolarity/ low volume stimulates thirst and ADH release
Which neurotransmitter is most involved in hunger signaling?
Neuropeptide Y (NPY)
How does ghrelin regulate hunger?
Low glucose levels stimulate ghrelin release from ghrelin cells along the GI tract- this stimulates the brain to make more neuropeptide Y- increasing hunger levels
How do leptin levels regulate hunger?
After meals leptin is released by (mainly) white adipose tissue. It inhibits neuropeptide Y so decreases hunger
What are adipocytes?
Modified fibroblasts that store almost pure triglycerides in liquid form
When will large quantities of fat start being deposited in the liver?
In any condition in which fat (instead of glucose) is used for energy
When does ketogenesis occur and where?
In mitochondria of liver cells
When acetyl-coA is created from lipids rather than glucose (also when glucose is very high)
What is the most abundant protein in adipose tissue?
Adiponectin (ACRP30)
Where does the majority of chemical buffering in the body take place?
Inside cells (70%)
What is the most important protein buffer which takes place inside RBC’s?
H+ + Hb = HHb
What is the Isohydric principle?
That all buffer systems work together as they all share H+. Thus when H+ concentration changes all buffer systems change at the same time
What do high and low ventilation rates do to pCO2 levels?
High ventilation rate = Low pCO2
Low ventilation rate= High pCO2
How much of your HCO3- should be lost in urine?
0.01%
In human cells, the reaction producing urea takes place in:
The cytosol
of hepatocytes
In a normal ~70 kg healthy male, renal blood flow is:
1200mL/min
The most selective pores in the glomerular filtration membrane are located in the…?
Podocytes
What is the drug phenytoin used for?
Prevention and management of seizures
especially in neurosurgery etc
What reaction is catalyzed by Asparate transaminase (AST)?
Aspartate (Asp) + α-ketoglutarate ↔ oxaloacetate + glutamate
(it transfers amino group from AA to keto acid)
What effect does insulin have on lipolysis in adipose tissue?
Reduces it
On histological examination of the kidney, how do the proximal convoluted tubules appear differentiated from distal convoluted tubules?
The PCT has a prominent brush border
Which amino acid that plays a central role in nitrogen flow and disposal of excess waste nitrogen in mammals is?
Glutamate
What is ammonia converted to in the body, where does this take place and why?
Ammonia is converted to urea
In hepatocytes
Because ammonia is toxic
What is the first step in the break down of amino acids?
Removal of alpha-amino nitrogen (deamination)
- This results in ammonia.
What is deamination?
Removal of an amine (nitrogen + lone pair)
What is the urea cycle?
Conversion of ammonia (NH3) to urea ((NH2)2CO2)
Where does glycolysis typically take place within mammalian cells?
The cytosol
Which cells converts haem to bilirubin?
Hepatocytes
Which cells can be exogenous stem cells for liver regeneration?
Bone marrow cells
What is the most useful test to diagnose intestinal malabsorption?
Hydrogen breath test
(perform after 8-12hr fast)
Diagnose IBS and food intolerance’s
(Unabsorbed food metabolised by bacteria which produces hydrogen or sometimes methane)
How is a urea breath test performed?
Px swallows 14C-labelled urea with 20 ml of water, then drinks another 20ml 3mins later
- 14CO2 then there is likely H.Pylori
What is the most major cell cycle checkpoint (i.e what stages does it regulate progression between)?
G2 to M
What is a zymogen?
A proenzyme (inactive) e.g pepsinogen
When are ANP and BNP released?
In response to high blood volume (high BP)
What is the action of ANP and BNP?
Vasodilate to lower BP
Causes increased GFR to get fluid/ solutes out
What two hormones are produced by the posterior pituitary gland?
Oxytocin
ADH (aka vasopressin)
What are the steps of glycolysis leading to the krebs cycle?
Acetyl CoA > 2xPyruvate (done by g-6-p)
Pyruvate > acetyl coA (decarboxylated by pyruvate dehydrogenase)
