Medicowesome

Wednesday, March 4, 2015

Study group discussion: Aortic regurgitation

What are the characteristic physical findings in aortic regurgitation?

You mean the characteristics signs from head to toe?

No, some special findings are present.

Collapsing pulse.

Yes, the water hammer pulse!

It was my viva question. I was asked to demonstrate it!

What else?

Like signs? Like pulsations at nail bed!

Yeah what's that called?

Pulsations at nail bed?

Quinckes sign!

Yes, exactly Quincke.

Hills sign.

The hills sign is the most significant.

What is hill sign?

Low BP in the upper limbs.

Upper limb bp is higher than lower limb.. Or vice versa.

Yup..right.. Cuz there's a difference of >10mmhg in upper and lower limbs..

And obviously, wide pulse pressure.

Plus, there is this austin flint murmur characteristic of severe AR.

Mullers sign - Pulsations of the uvula

Corrigans sign - Carotid pulsation visible

Landlof's sign

Oh landolf's sign is alternate dilatation and constriction of pupil with each heart beat.

I know Mussetts - the head bobbing

Traubes, I think, is shotty femoral pulse!

Lighthouse sign!

Lighthouse sign is blanching and flushing of forehead with each heart beat..

Duroziez - murmur over femoral artery

Locomotor brachii.

What's that?

Oh yes.. Locomotor brachii is the Thickened, tortuous brachial artery on Inspection.. You can see the twitchings clearly especially on the medial side of arm.. It basically indicates hypertension but commonly associated with AR.. I've seen it in patient with AR..

Which is the most diagnostic sign? Which is the most important of all the signs of aortic regurgitation?

The diastolic murmur is diagnostic of all!

Even mitral stenosis has a diastolic murmur! It should be Hills!

In MS, we also have the opening snap.. You need practice to be quick in identifying the psa and opening snap. Where as hills can be diagnosed with a BP cuff!

And there is difference in the sounds too.

Theoretically, we read that.. Frankly, I find it a great achievement if I can only say with confidence whether it's diastolic or a systolic murmur.

True!

Haha that's the truth actually!!

Aortic regurgitation -Soft blowing early diastolic decrescendo murmur.
Heard best at the left 2nd ICS without radiation.
May also hear systolic flow murmur and diastolic rumble (Austin Flint)

Mitral stenosis -Low frequency rumbling mid-diastolic murmur, with presystolic component possible.
Heard best at apex.
Accentuated in left lateral decubitus position.

What's the amount of blood regurgitated in aortic regurgitation?

Its 25% of ejection fraction

In mild AR?

What about moderate and severe types?

Maybe increases, I have to check.

It does. But since you were specific to say 25% There has to be specific values of the other two classes as well.

In severe, its more than 50% I think, correct me if I'm wrong.

Will check out my books.

I had an aortic regurgitation case in my finals too.
I thought I was reading the blood pressure wrong but... The diastolic was 20mm Hg.
It can go so low.. The diastolic can even go till zero is what my professor said!

Tuesday, March 3, 2015

Study group discussion: Diabetes

I've noticed one thing with my "swedish" medical book.... It always give glucose values in ( mmmol/l ) and not ( mg/dl )

fP-Glucose > 7,0 mmol/l
How much mg/dl is that ?

The conversion factor is mg/dl= 18 x mmol/l
So 7mmol/l is 126mg/dl
I'm actually majoring in pharmacology :) we had a lot of those ^^

HbA1c < 52 mmol/l = 6 %
For diabetes type 1
Hemoglobin A1c level should be held at 6%
I'm reading about diabetes type 1 treatment
And it's written here HbA1c level should be held < 52 mmol/mol
equals to 6%

*a conversion table was posted on the group by someone which sorted this dilemma*

That might be possible but for the diagnosis it is >6.5

You don't use A1c for diagnosis. It is used only for evaluating control over the last few months!

But now if it's >6.5 he is diagnosed diabetic.

Umm but.. Why would you use such a test when there are better screening tests?

Ummm its part of one of the criteria for diagnosis!! Though getting fasting samples and all are easy but you have to make the patient fast right!! In this one benefit would be take the samples anytime!

Oh yep.. Makes sense!

A diabetic patient is undergoing contrast angiography for some reason. He was asked to stop his oral hypoglycemic, metformin before the procedure. Why?

Lactic acidosis.
Renal failure will worsen it.
Contrast leads to renal damage.

Correct! You are concerned about lactic acidosis. Even slight renal failure due to the dye will precipitate lactic acidosis!

A diabetic patient controlled on Insulin develops fainting episodes. On investigations, he was found to have an elevated creatinine. What is the mechanism for the hypoglycemia?

Insulin excreted renally?

Yes, the half life of insulin is increased in renal failure!

A nurse presents with hypoglycemia. Her insulin levels are up but C peptide levels are low. Diagnosis?

Taking exogenous insulin.

Alright. You confront the patient and goes into counselling.

Now the same patient comes with hypoglycemia but this time her insulin and C peptide levels, both are elevated!
What happened this time?

Using sulphonylureas
Oral diabetic drugs - Glipizide, glimipiride, glyburide

Correct! How will you prove it?

proInsulin levels? Just guessing don't know that!!

U/A

What's u/a?

U/A is shortening for urine analysis

Correct! Urine for Sulfonylureas

If the urine test came negative, what could it be?

Insulinoma

And he scores again!

Wonderful questions!!

That'll be all for today!

Thank you for the great questions IkaN.

Never thought questions would be this much fun!

*After which someone else asked us a few review questions based on what he had studied! *

Which antidiabetic drug can lead to SIADH?

Chlorpropamide

I would take that!! All sulphonylureas lead to SIADH.

Ok one more!! How would you access severity of diabetic ketoacidosis?

*since no one could guess, we were given hints!*

Let me put in this way.. Which electrolyte would you Check in serum to access severity of DKA?

If you had to check just 1.

Bicarbonate.

Yes!!!

Why bicarbonate?

Because it is acidosis

Yes, you are right!!

Low bicarbonate would lead to what? This one entity is very important in DKA management! If this is corrected patient is well and good!! Some difference in the cations and anions!! What's that called?

Anion gap

Yes, it is!! Finally!!

This anion gap is very important.

What the normal value?

10 to 15

Does this gap increase or decrease?

Increases.

ABG would tell is about acid base imbalance.

How does neuropathy occur in diabetes? What's the mechanism?

Occlusion of small venules?

Damage to autonomic NS..?

Microvascular occlusion?

Yes, nerves themselves have a supply of blood vessels. Diabetes damages these small blood vessels, thus decreases supply to nerves!!

You all were correct!!

I've read somewhere that sorbitol deposits also damage nerves?

Lens! It causes cataract.

Alright guys!! That's it!! I can't remember any more!!

Any mnemonics?

Here are all the study links!

http://medicowesome.blogspot.ae/2015/01/oral-hypoglycemic-drugs-and-weight.html

http://medicowesome.blogspot.com/2015/02/study-group-discussion-pharmacological_15.html

http://medicowesome.blogspot.ae/2015/02/study-group-discussion-metformin-and.html

http://medicowesome.blogspot.ae/2015/02/study-group-discussion-cardiac.html

http://medicowesome.blogspot.ae/2015/02/study-group-discussion-type-3-diabetes.html

Study group discussion: Pre-eclampsia and HELLP syndrome

Anybody up for discussion on eclampsia? :D

What is cause of right upper quadrant Pain in HELLP syndrome?

Stretching of the liver capsule.

What's the earliest sign of pre-eclampsia?

It's excess weight gain.

Why?

Due to retention of water.

Study group discussion: Electrolyte abnormalities that cause constipation

Q) Which electrolyte abnormalities can lead to constipation?

My friend says calcium.

Yes, hypercalcemia.

He screamed in my ear because he got excited :L

Hahaha

Hypercalcemia
Hypermagnesemia
Hypokalemia
Hypophophatemia

How does hypercalcemia lead to constipation??

Hypercalcemia increases the action potential threshold and hence decreased contraction n peristalsis.

Sounds good!! Thanks!!

Study group discussion: Chionablepsia and Anisakiasis

Learnt some new words today!
Chionablepsia - its inflammation of eyes due to UV rays!

What a word. I can't even pronounce it!

And this word has no -itis😃

They should've come up with uv-eye-itis instead! :P

Hehe

One more!

Anisakiasis !

A parasitic infection by anisakid (nematodes)

What does this parasite infect?

Stomach walls!

Caused by ingestion of larvae...say, by consuming infected squid or fish

Since it affects the stomach walls, wouldn't bleeding or abdominal pain be most prominent symptoms?

Nothing special ....abdominal pain, nausea, vomiting, diarrhea.

Oh alright!

Deceptive appearances.

A few medical conditions have presentations that are more or less the same to a layman but in reality, are polar opposites of each other. There are though, a few subtle clues which help in differentiating these conditions. Some of them are as follows-

1. The Somogyi effect and the dawn phenomenon.
These are the conditions which occur in diabetic patients which are undergoing treatment.

In the Somogyi effect, there is a rebound hyperglycemia (in the mornings) following hypoglycemia(during the night) due to the release of counter regulatory hormones.

On the other hand,the dawn phenomenon is characterized by morning hyperglycemia due to inadequate insulin dosage. It may be a possibility that the raised blood sugar is due to nocturnal GH release or increased insulin clearance in the mornings.

So, what does the patient think? That the treatment is not working, is inadequate, but the reality may be starkly different.

To pinpoint, the patient may be asked whether he feels excessive hunger during the night, experiences persistent nightmares or any other symptom during night pertaining to hypoglycemia.

3am and morning blood samples reveal hypo and hyperglycemia in the case of Somogyi effect, while hyperglycemia both the times with dawn phenomenon.

Hence, the modification in Somogyi effect is actually to decrease the insulin dose and increasing it if the patient has dawn phenomenon.

2. Anorexia and Bulimia nervosa.
Both these conditions are characterised by the patient having weight concerns and multiple episodes of self induced vomiting ,laxative abuse or extreme exercise and fasting.One might get confused as to what exactly is the underlying condition.

The primary difference between the two according to me is the patient's attitude and the quantity of food consumed.

Anorexics are primarily worried about their weight(they tend to be ballet dancers or actresses) and hence consume very less amount of food to begin with and vomit out or use laxatives to get rid of whatever is consumed. The patient tends to be almost emaciated, they have a distortion of the bodily image and beliefs that they are still overweight.

Bulimia patients too, engage in similar kinds of behaviours to lose calories but these are more driven out of guilt rather than extreme weight concerns,they usually have a normal weight.The patients have a sense of achievement that they can eat whatever they want and in any quantity until they are losing calories through vomiting, excessive exercise or laxative abuse. Contrary to anorexia, patients have episodes of binge eating then compensatory behaviours followed by hunger and then again binge eating.

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Monday, March 2, 2015

Study group discussion: Difference between antibody and anti-toxin

What is the difference between an antibody and an antitoxin? Wikipedia says that antitoxin is also an antibody. But what's the difference between the two?

And if we take a vaccine, what is formed-an antibody or an antitoxin?

My understanding is a toxin cam be an antigen. An antigen is not necessarily a toxin. So an antitoxin can be an antibody, but not all antibodies are antitoxins.

Anti-toxin is something that neutralizes the toxins released by bacteria. Ex: Tetanospasmin released by Cl. tetani.
These conditions are life threatening acutely.. So you give pre-formed anti-toxin from horse serum or from multiple plasma donors.

Anti-toxin are antibodies. But you need to remember it is especially for neutralizing toxins released by bacteria.
Whereas, antibody is a very vast term. They can be formed against the cellwall of bacteria as well as one's own antigens (autoimmunity).

Multiple plasma donour means from many organisms?

When people donate blood, the antibodies from several of these people's blood is collected and given

Good explanation, Sakkan!

Study group discussion: Aspirin

Which is the classical triad of aspirin poisoning?

Idk the triad though... I just know some symptoms.

What are the symptoms?
Dehydration
Petechiae
Fever

The triad is hyperpyrexia, confusion and later death.

Death? :O

A very rare case.

Death is due to Respiratory collapse.

Fever? A drug used for pyrexia causes fever :D

Haha ironic, yes.

Pyrexia because of uncoupling of oxidative phosphorylation.

Yep. The energy in ATP gets disseminated in the form heat.

What is the treatment of aspirin overdose?

No specific antidote.
Symptomatic.. Cooling.
Vit k - For petechiae.

Increasing urine pH.

Right on! Aspirin is a weak acid.. Hence you increase its ionization to reduce absorption.. By giving sodium bicarbonate!

Yes!! Alkaline diuresis it's called!

Aspirin you just manage patient. Give iv fluid, increase urine pH, dialysis.

Dose of aspirin for prevention of MI?
Dose of aspirin in ongoing MI?

For prevention it is 81-160
For ongoing.. It is 160-325
Moving on

Why salicylates are contraindicated in children?

Reyes syndrome. They result in increase in liver transaminases plus encephalopathy.

Especially, when used for kids with viral fever.

Study group discussion: Cycloserine

I just came to know that One of the important side effects Cycloserine is suicidal tendencies!

And Cycloserine is used in MDR TB.

Exactly.

Does it have any other uses? Apart from TB?

Mental retardation... I searched online.

Hmm.

The person with MDR TB...Dies of suicide more often.

Now we know why!

No other infections?

Certain UTIs. It's antimicrobial action is due to inhibition of bacterial cell wall.

I see.

Study group discussion: Lymph nodes in various diseases

Characteristic lymph nodes in diseases:

Matted- Tuberculosis, LGV

Rubbery- Hodgkin's lymphoma.

Shotty- Syphilis.

Hard, fixed - Malignancy.

Do you know any more? Let us know in the comments section below!

Study group discussion: Biceps femoris reflex

Does anyone know what biceps femoris reflex is?

Biceps femoris reflex is a highly sensitive and reliable clinical tool for evaluation of the S1 spinal reflex pathway in radiculopathy.

It's the contraction of biceps femoris muscle when it is tapped on the lower part of its head just above its attachment on the head of fibula, with the limb slightly flexed at hip and knee.

Hope this helps :)

Thanks!

Study group discussion: ACE in lung diseases

Can anyone please explain why Serum ACE is elevated in Sarcoidosis?

ACE activity is increased in sarcoidosis, a systemic granulomatous disease that commonly affects the lungs. In sarcoidosis, ACE is thought to be produced by epithelioid cells and macrophages of the granuloma.

Serum ACE also appears to reflect the activity of the disease so we can estimate the severity or response to treatment..

You mean : Higher the ACE level , more the disease severity?

Yes.. Higher the level more the severity.

Got it . Thank yoh!

Both TB and sarcoidosis has increased levels of Adenosine Deaminase but Sarcoidosis can be distinguished from tuberculosis by serum ACE levels (In tuberculosis, decreased levels of serum ACE.)

Woah.

Study group discussion: Drug for neurological manifestations of Wilson's disease

Review question-
Which drug is used for neurological manifestations of Wilson's disease?

Penicillamine (cuprimine and depen) and trientine (syprine and trientine dihydrochloride).
Both of these drugs act by chelation of binding of copper, causing it's increased urinary excretion.

Yes, but any specific drug for neurological involvement?

It's Ammonium tetrathiomolybdate.

Glycogen storage diseases mnemonic

Hey everyone! Long time no see!

I was requested mnemonics for glycogen storage diseases recently so I thought I'd write about it -

Glycogen storage diseases from 1-6 are:
von Gierke's disease
Pompe's disease.
Cori's disease
Anderson’s disease
McArdles disease
Hers disease

The memory aid for remembering this one is actually a dirty mnemonic, I found it on tumblr (Can't remember where I read it!)

Anyway the mnemonic is -

Viagra
Pills
Cause
A
Massive
Hardon

Also, heart pumps (Pomps) blood. So that's how you can remember that the heart is affected in Pompe's disease!

And for the enzymes -

Glycogen storage disease type 1 mnemonic:
Geirke - Glucose 6 phosphatase. Both have a G!

Glycogen storage disease type 2 mnemonic:
The Pompe's disease mnemonic is a drag but for whoever this helps.. Do you guys know about the volcanic eruption in Pompeii?
The fires of Pompeii makes me think of acid (burns-fire-acid?) and how it killed children.
So acid alpha-glucosidase and affects children!

Glycogen storage disease type 3 and 4 mnemonic:
Mnemonic for Anderson’s and Cori’s is, "ABCD"
A-B(ranching)
Anderson’s - Branching enzyme.
C-D(ebranching)
Cori’s - Debranching enzyme.

Glycogen storage disease type 5 mnemonic:
Muscle phosphorylase for McArdles. Both have a M in the name!

Glycogen storage disease type 6 mnemonic:
LivHER. So Liver phosphorylase is affected in Hers disease.

That's all!

Hope you're having a wonderful time and see you in the next post xo

-IkaN

Study group discussion: Thyroid surgery practicals viva questions

Anyway, speaking of triangles of the neck.. Do you guys know they are super important for surgery vivas?

I have surgery viva coming up !!

Omg. If you have a thyroid case, they are bound to ask you this!

I have thyroid - surgery review questions :D

Who is father of thyroid surgery?

Answer: Kocher

Which artery is ligated in thyroid surgery?

Answer: Superior thyroid artery

Why don't you ligate two?

Answer: Superior thyroid artery is only ligated. The inferior one is left. If you ligate the inferior thyroid artery, the two inferior parathyroids will necrose. Hence the current dictum is not to ligate the ITA.

What about which artery to be ligated near the gland and which one far?

Answer: You ligate STA as near to the gland as possible to avoid injury to the nerve which runs along with it.

Differential diagnosis of midline neck swelling?

Thyroglossal cyst and thyroid are the common ones.

Thyroglossal cyst is embryological remanant of?

Thyroglossal duct.

Most early cause of respiratory difficulty postoperatively?

It's tracheomalacia. Immediately as soon as you withdraw the ET tube.. The trachea collpases.

Reason?

Tracheomalacia is an inherent condition of weakness of the tracheal cartilage. The thyroid keeps it patent. After thyroidectomy, it might collapse.

Interesting.. Didn't know this!

Which thyroid cancer can form renal stones?

Medullary. Due to calcitonin.

At abnormally high levels, it increases urinary excretion of calcium causing renal stones. Medullary carcinoma can also present with hypocalcemia.

In thyroid surgery, why are we ligating middle thyroid vein first?

To prevent metastasis or to prevent formation of seedling in case of cancer.

Can anyone please elaborate why hyperthyroidism causes oligomenorrhea and hypothyroidism causes menorrhagia?

Hypothyroidism increases TRH.
TRH increases prolactin.
Prolactin decreases GnRH.
GnRH decreases LH and FSH.

What are the complications of multinodular goitre?

Complications of MNG - Due to obstruction - Dyspnea, dysphagia.
Malignant change, calcification are also complications.

Thanks :)

Study group discussion: Pressure and volume reservoir in the human body

Why arteries are labelled as pressure resevoir?

All artery..especially, arterioles are the main site of pressure regulation.
Veins on the other hand are called capacitance. They store at a time 60% of the total blood volume.
Therefore arterioles regulate the pressure. On the other, hand..Veins monitor the volume of blood reaching the heart

I think that is true.
And vein also called main blood resevoir.

I found out a good explanation on - Why arteries are known as pressure reservoirs?

Arteries also contain an elastic layer in their walls. Elastin is a protein fiber that has elastic qualities. During systole, large arteries distend with blood as their elastic walls stretch. During diastole, the walls rebound, thus pushing blood along. In this way the arteries act as a pressure reservoir that maintains a constant flow of blood through the capillaries despite pressure fluctuation during the cardiac cycle.

Veins on the other hand, are known as blood reservoirs.

Veins are larger and more compliant (stretchable) than arteries, thus they can hold more blood. In fact, the veins act somewhat like a blood reservoir, containing 60% of the total blood volume at rest.

Study group discussion: Morphine and atropine

* Our discussion started with this: Acute LVF management
LMNOP:
Lasex (frusemide)
Morphine (diamorphine)
Nitrates
Oxygen (sit patient up)
Pulmonary ventilation (if doing badly)*

Morphine used even in the absence of infarction?

To treat severe pain.. Morphine is powerful analgesic.

Yes, but in which cases other than MI, pain is a significant symptom?

Post surgical pain, Cancer pain.

Morphine is indicated in only acute stabbing visceral pain. Except in abdominal emergency's.
Abdominal emergencies if due to biliary spasm. Give nitrous oxide. Or else pethidine.

Even for abdominal pain, if it's severe once after the examination of abdomen.

No, we don't use morphine in abdominal emergencies.

I think we do apart from biliary conditions.

Posting this again, since it's relevant. Opioids, morphine mnemonic http://medicowesome.blogspot.ae/2014/04/opioids-and-other-analgesics-mnemonic.html

Biliary spasm is due to contraction of sphincter of Oddi. Right?

Yep.

Is morphine used alone in biliary spasm??

No, no. It's specifically contraindicated in acute abdominal pain. Because it cause biliary spasm.

Yes, but if used along side of some particular drug it releives spasm.. What drug is it??

I think it's atropine.. Is that right?

Yes!

Atropine is used with morphine for treatment of renal and biliary colic.. Morphine alone may aggravate pain by causing spasm of sphincter of oddi.. Atropine relaxes the smooth muscle of gallbladder and increases the intrabiliary capacity and counteracts the spasmogenic effect of morphine..

I was asked this in a viva, why is atropine given before procedures like drainage of pleural effusion aka pleural tap?

Ummm don't know!!

Okay, I'll give you a hint.. What will happen when you push the needle into the patient

Bleeding?!

And?

Bleeding is minor, think of other things!

Atelectesis?!!

Think Neurologic.

Shock?

Yep. Vasovagal shock. That's why atropine is administered half an hour before the procedure.

Oooh.

Wow! Didn't know that!!

This should apply to all procedures then!

Yes, all procedures. But I was asked this specially because my case in finals was pleural effusion.

Thanks IkaN!

Study group discussion: Central trachea in pleural effusion

In which pleural effusions the trachea is central??

Bilateral ??

Okay.. But in which unilateral conditions?

Due to bronchogenic ca?
When there is pull + push of trachea, nullifying it?

Umm.. It's because of mesothelioma

Why?? I mean why specifically I'm mesothelioma?

If pleural effusion is because of mesothelioma then the negative pressure created by it doesn't effect that much... Sorry.. Don't know exactly.. I'll let you know..

In absorption collapse such as in bronchiogenic ca or foreign body impaction,
Bronchus is obstructed, intrapleural pressure remains negative and trachea is shifted to the same side.

In cases of compression collapse due to pleural effusion, pneumothorax or hydropneumothorax,
Bronchus is patent, intrapleural pressure is positive n so trachea is pushed to the opposite side.

So, if there is bronchogenic ca with pleural effusion, both mechanisms take place,
If pulling effect by bronchogenic ca plays more, trachea remains on the same side of effusion.
If both plays equally, trachea remains in central

Ah.. Push and pull which I mentioned earlier. Thanks a ton!

Study group discussion: Scissoring posture

1 and a half year old child when suspended by the axillae, his legs maintain scissoring posture. What can you think of?

Cerebral palsy!
Or UMN lesion!

Which type?

Spastic diplegia

What is the reason for such kinda posture?

Scissoring is a sign of hypertonia.

Patient tone is increased!!

Yes

Everything related to UMN lesion

Spasticity, hyper reflexia, upgoing plantar.. You will see in this patient!

What can be the possible treatment?

Baclofen + physiotherapy.
A pillow or ball between the legs while sleeping!

Yeah, baclofen will relieve the spasticity.

Study group discussion: Cutaneous signs of insulin resistance and lipoproteinemia

These are skin tags. What do you think of when these are present?

Aren't these harmless with no associated risk?

Nope. They represent something! Ok! These are signs of insulin resistance!

What are other cutaneous signs of insulin resistance?

Acanthosis nigricans

Yes!!

One more.. Although that one is associated with hyperlipidemia too.

Xanthelasma?

Yes!!! Xanthelesma.

Since we are on hyperlipidemia http://medicowesome.blogspot.ae/2013/08/how-to-remember-lipoprotein-disorders.html

So cutaneous signs of insulin resistance include:
Skin tags
Acanthosis Nigricans and
Xanthelesma

Mnemonic: SAX!

In which condition do you see orange tonsils?

Rifampicin intake?

Haha nope. It's related to the topic.. A high cholesterol condition!

Lol no idea then!

Tangier disease.. It's due to lack of cholesterol transporter gene. The disease is characterized by atherosclerosis, hepatosplenomegaly, polyneuropathy and orange tonsils.

Ohh!!!

Another review question.. Why is type 1 lipoproteinemia associated with pancreatitis?

Short of knowledge on this topic maybe someone else would answer it?

It's because chylomicrons obstruct the pancreatic duct.