AN OVERVIEW OF THE NEET PG ENTRANCE EXAM
by Dr. Prateek Charuchandra Joshi (DNB AIR 291, MH state rank 51)
by Dr. Prateek Charuchandra Joshi (DNB AIR 291, MH state rank 51)
Wednesday, March 22, 2017
Tuesday, March 21, 2017
Brainstem Syndromes-Pons!
Hellooo people!
After travelling from the Midbrain I we have reached the Pons.. which literally means a Bridge... So .... Let's study the important eponymous Pontine syndromes today...
1) Millard-Gubler Syndrome:
Lesion location:Pons
Structures affected: CN VII ,Corticospinal tracts!!
Clinical features: Ipsilateral peripheral facial palsy; contralateral hemiparesis ,CN VI not involved
Foville's Syndrome(Raymond-Foville) :
Lesion location:Pons
Structures affected:CN VII; lateral gaze center; Corticospinal tracts.
Clinical features • Ipsilateral facial palsy and horizontal gaze palsy; contralateral hemiparesis
Raymond's (Yelloly, Landry) Syndrome: Lesion Location: Pons
Structures affected: CN VI; Corticospinal tracts
Clinical Features: Ipsilateral abducens palsy; contralateral hemiparesis ,it is often lumped with Foville's syndrome.
There are other Pontine syndromes ...And an Anatomical classification of them makes them easy to understand !
I shall in the next post put up the respective syndromes along with associated diagrams..
Till then... Study Well Guys!
Also I would like to say... Medicine is not just science and theory but also an art to be understood.... So we all need to have the artists eyes and spot out the subtle presentations of the diseases in our patients and treat them with all our hearts!
-Medha!
Monday, March 20, 2017
Fact of the day: High maternal cortisol good for foetal brain
Hey Awesomites
Neurodevelopment attained in the foetal period is greater than in any other period of an individual's life. Foetal exposure to "optimal levels" of maternal cortisol in third trimester has been linked to better cognitive and functional performance in the child.
Maternal cortisol acts on its receptors present in amygdala, hippocampus and the pre - frontal cortex ( PFC ) in high amounts. This hormone influences various stages of neurodevelopment including neurogenesis, axonal development, and myelination of nerve fibres and thus it leads to increased cortical thickness in frontal part of the brain and increased brain maturity.
( Source )
Thats all
- Jaskunwar Singh
Neurodevelopment attained in the foetal period is greater than in any other period of an individual's life. Foetal exposure to "optimal levels" of maternal cortisol in third trimester has been linked to better cognitive and functional performance in the child.
Maternal cortisol acts on its receptors present in amygdala, hippocampus and the pre - frontal cortex ( PFC ) in high amounts. This hormone influences various stages of neurodevelopment including neurogenesis, axonal development, and myelination of nerve fibres and thus it leads to increased cortical thickness in frontal part of the brain and increased brain maturity.
( Source )
Thats all
- Jaskunwar Singh
Saturday, March 18, 2017
Differentials of Unilateral Central Scotoma
Hey, guys this post will be on the differential diagnosis of "Blurred Vision in one eye" due to a central scotoma.
So a central scotoma can be usually due to retrobulbar neuritis(inflammation of the optic nerve) or optic nerve compression.
Now when you have detected a central scotomata in one eye it is essential to do the confrontation test in the other eye also. If in the other eye you detect a defect in upper temporal field, a superior temporal quandrantonopia; it is higly likely that this is a case of optic nerve compression.
How so? Well refer the attached pic with the illustrated diagram and I am sure you will understand. :)
-VM
So a central scotoma can be usually due to retrobulbar neuritis(inflammation of the optic nerve) or optic nerve compression.
Now when you have detected a central scotomata in one eye it is essential to do the confrontation test in the other eye also. If in the other eye you detect a defect in upper temporal field, a superior temporal quandrantonopia; it is higly likely that this is a case of optic nerve compression.
How so? Well refer the attached pic with the illustrated diagram and I am sure you will understand. :)
-VM
Friday, March 17, 2017
Studying made simple: Ocular signs of thyrotoxicosis
Hey Awesomites
I read about ocular signs seen in patients with thyrotoxicosis. On googling and partly my work, studying these signs has become so simple to remember. -
I read about ocular signs seen in patients with thyrotoxicosis. On googling and partly my work, studying these signs has become so simple to remember. -
Lhermitte's sign Variants!
Helloooo....
Well we all know about the Lhermitte’s sign... The famous Barber's Chair sign!
For the people who are reading for the first time... Lhermitte's sign is a sensation of tingling or electric shocks running down the back and legs on flexion of the neck.
Some other actions giving rise to similar sensations are: Neck rotation, arm abduction, coughing ,Yawning
It is common in multiple sclerosis, and other demyelinating diseases but can occur with other conditions involving the cervical spinal cord.
But...Some variants to Lhermitte’s sign have also been described.
1) Delayed typical Lhermitte phenomenon can follow contusion of the spinal cord from neck trauma.
2) Reverse Lhermitte phenomenon
Paresthesias induced by neck extension have been described in extrinsic compression of the cervical spinal cord.
3) Inverse Lhermitte's sign:
Upward moving paresthesias with neck flexion have been described in myelopathy from nitrous oxide inhalation.
I hope this was informative!
-Medha!😊
Brainstem syndromes-Midbrain!
Here we shall review three syndromes in the Midbrain occuring majorly due to a vascular event.
Weber's Syndrome:
Lesion Location: Midbrain base
Lesion Location: Midbrain base
Structures involved :CN III fibers; cerebral peduncle
Features: Ipsilateral CN III palsy; contralateral hemiparesis
(The image showing the involved 3 nerve and the crus! The lesion is anterior—in the cerebral peduncle—in Weber’s syndrome, causing hemiparesis.)
Claude's Syndrome:
Lesion location :Midbrain tegmentum
Lesion location :Midbrain tegmentum
Structures involved: CN III fibers; red nucleus; SCP
Clinical features: Ipsilateral CN III palsy; contralateral ataxia and tremor (“rubral tremor”)
(The sky blue line depicts the sup. Cerebellar peduncle! Lesion is more posterior—in the tegmentum—in Claude’s syndrome, causing hemiataxia.)
Benedikt's Syndrome:
Lesion location: Midbrain tegmentum
Lesion location: Midbrain tegmentum
Structures involved: CN III fibers; red nucleus; CST (corticospinal tract)SCP(superior cerebellar peduncle)
Clinical features:
•Ipsilateral CN III palsy; contralateral hemiparesis with ataxia, hyperkinesia and tremor “rubral tremor
(The blue fibers being the sup. Cerebellar peduncle. In Benedikt’s syndrome, the lesion is more extensive, involving both the tegmentum and the peduncle, causing hemiparesis with tremor and ataxia of the involved limbs)
These three midbrain syndromes are variations on a theme.
•Ipsilateral CN III palsy; contralateral hemiparesis with ataxia, hyperkinesia and tremor “rubral tremor
(The blue fibers being the sup. Cerebellar peduncle. In Benedikt’s syndrome, the lesion is more extensive, involving both the tegmentum and the peduncle, causing hemiparesis with tremor and ataxia of the involved limbs)
These three midbrain syndromes are variations on a theme.
Benedikt’s is essentially Weber’s + Claude’s.
Because the fascicles of cranial nerve (CN) III are scattered in their course through the midbrain, the third nerve palsy in any of these syndromes may be partial.
Last on the list....
Nothnagel's Syndrome mainly due to neoplasms ...affecting the Midbrain tectum involving Ipsilateral or bilateral CN 3 causes Oculomotor palsies; ataxia.
We finish Alll the midbrain syndromes !!!!!😎
Hope it helps!
-Medha😊
Facts and Fallacies: Vitamin D link to cancer
Hey Awesomites
Vitamin D has been shown beneficial for a variety of disorders and diseases. Recent studies now suggest that those deficient in vitamin D are at a higher risk of developing cancer compared to those with adequate levels.
Vitamin D has been shown beneficial for a variety of disorders and diseases. Recent studies now suggest that those deficient in vitamin D are at a higher risk of developing cancer compared to those with adequate levels.
Brainstem Syndromes!
So let's get done with all the important brainstem syndromes once and for all !
I would be writing on all of them one by one...
Also ...I will try and incorporate many of my diagrams to help you guys make it seem less daunting...
Starting from the Midbrain the first syndrome is..
(The image shows the level of the lesion)
1):Parinaud's Syndrome
Lesion location:Midbrain dorsum ,superior collicculi.
Structures involved: Quadrigeminal plate region; pretectum; periaqueductal gray matter
Etiology: •Due to mass lesion in the region of the posterior third ventricle, most often pinealoma, or due to midbrain infarction.
Clinical features:
•Impaired upgaze as centre for upward gaze is affected
convergence retraction nystagmus;
Argyll Robertson pupil :dilated pupils with light near dissociation.
•Impaired upgaze as centre for upward gaze is affected
convergence retraction nystagmus;
Argyll Robertson pupil :dilated pupils with light near dissociation.
A closer look at the structures involved .
I hope it helped !Also do share your Neuroanatomy diagrams and and more information on Parinaud Syndrome.
Have a nice day!
-Medha!
Thursday, March 16, 2017
How I remember the duration of symptoms for Generalized anxiety disorder (GAD) required for diagnosis
The symptoms of generalized anxiety disorder should be present for at least 6 months. For me, it's hard to remember the duration of the symptoms in psychiatry. So I mnemonic-ify them :D
I remember G6PD, and say G6AD instead!
For those who don't know what GAD is here is the DSM V criteria for diagnosis of Generalized Anxiety Disorder...
I remember G6PD, and say G6AD instead!
For those who don't know what GAD is here is the DSM V criteria for diagnosis of Generalized Anxiety Disorder...
Transposition of Great Arteries!
Hello!
So I have divided the post into two parts - A short summary for those who don't have the time to read everything (#TLDR) and a nice long explanation for those who want to read everything :)
Let's start with TLDR.
Buzz words for congenital syphilis!
Following are some important signs and buzzwords that are testable ...And high yeild for entrances.
Olympian Brow: Bony prominence of the forehead caused by persistent or recurrent periostitis
Clavicular or Higoumenakia sign:Unilateral or bilateral thickening of the sternoclavicular third of the clavicle
Saber shins :Anterior bowing of the midportion of the tibia
Scaphoid scapula :Convexity along the medial border of the scapula
Hutchinson teeth:Peg-shaped upper central incisors; they erupt during 6th yr of life with abnormal enamel, resulting in a notch along the biting surface
Mulberry molars :Abnormal 1st lower (6 yr) molars characterized by small biting surface and excessive number of cusps
Saddle nose :Depression of the nasal root, a result of syphilitic rhinitis destroying adjacent bone and cartilage
Rhagades:Linear scars that extend in a spoke-like pattern from previous mucocutaneous fissures of the mouth, anus, and genitalia
Juvenile paresis :Latent meningovascular infection; it is rare and typically occurs during adolescence with behavioral changes, focal seizures, or loss of intellectual function
Juvenile tabes : Rare spinal cord involvement and cardiovascular involvement with aortitis
Hutchinson triad :Hutchinson teeth, interstitial keratitis, and 8th nerve deafness
Clutton joint :Unilateral or bilateral painless joint swelling (usually involving knees) from synovitis with sterile synovial fluid; spontaneous remission usually occurs after several weeks
Interstitial keratitis: Manifests with intense photophobia and lacrimation, followed within weeks or months by corneal opacification and complete blindness
8th nerve deafness: May be unilateral or bilateral, appears at any age, manifests initially as vertigo and high-tone hearing loss, and progresses to permanent deafness.
Well all these are late manifestations of congenital syphilis occuring after 2 years of life.
It is important to recognise these signs clinically and also on the exams...
-Medha.
Pathophysiology of myopathy caused during hypothyroidism and hyperthyroidism
Hello awesomites! Today's topic of discussion is - Myopathy in thyroid disease.
Interestingly, it is caused by both, hypothyroidism as well as hyperthyroidism.
What is myopathy?
It is a disease of muscle tissue where, ultimately, muscles get weak and are unable to perform work due to deficiency of ATP.
Why is there myopathy in hyperthyroidism?
The thyroid hormone is a catabolic hormone. Hyperthyroidism increases energy expenditure, glucose turnover, lipolysis, and protein breakdown (proteolysis). But here is the catch - Hyperthyroidism increases whole-body protein turnover and breakdown before any measurable changes in energy expenditure or glucose and fat metabolism, suggesting that amino acid and protein metabolism is an early and primary target for thyroid hormone action in humans. It was therefore concluded that the thyroid-hormone concentration may be an important factor in regulating muscle proteolysis. The altered protein metabolism causes myopathy.
Then, one may ask, why myopathy in hypothyroidism? Less thyroid hormone should lead to less protein breakdown, shouldn't it?
Well, this is a good question! Slightly complex and tricky to answer though.
In hypothyroidism, there is abnormal glycogenolysis, defective mitochondrial oxidative metabolism and triglyceride storage.
Abnormal glycogenolysis and triglyceride storage: Less glucose is released and utilised because of this. The body starts using more proteins usually derived from muscles leading to myopathy.
Mitochondrial oxidative metabolism defect: Thyroid hormone is responsible for activation of bc1 complex also known as complex 3 & succinate dehydrogenase. Less activation of bc1 leads to less formation of ATP from glucose.... So again, the body switches to proteins from muscles as a source of energy!
That's all!
Stay cool :)
Stay cool :)
~Ojas
Wednesday, March 15, 2017
Fact of the day: Regulate brain activity with your type of music
Hey Awesomites
Which genre or type of music do you like the most? Well, it surely has to do a lot with the functioning of our brain. Some of you may like slow music while others like to rock n roll on the floor while listening to their favourite beats. I am more of the latter type too, depending on the mood. ;p
Which genre or type of music do you like the most? Well, it surely has to do a lot with the functioning of our brain. Some of you may like slow music while others like to rock n roll on the floor while listening to their favourite beats. I am more of the latter type too, depending on the mood. ;p
Tuesday, March 14, 2017
Pediatric drawing milestones mnemonic
I share two mnemonics in this video - The count numbers on your hand mnemonic and the draw it yourself mnemonic xD
Tricyclic antidepressants (TCAs) - MOA and side effects
Hello!
This is a fun and concise post on the pharmacology of TCAs. Excited? :D
This is a fun and concise post on the pharmacology of TCAs. Excited? :D
Monday, March 13, 2017
Saturday, March 11, 2017
Fact of the day: Paradoxical undressing in fatal hypothermia
Hypothermia causes paradoxical undressing.
This typically occurs during moderate to severe hypothermia, as the person becomes disoriented, confused, and combative. They may begin discarding their clothing, which, in turn, increases the rate of heat loss. It is estimated that twenty to fifty percent of hypothermia related deaths are due to paradoxical undressing.
Why does this happen?
This typically occurs during moderate to severe hypothermia, as the person becomes disoriented, confused, and combative. They may begin discarding their clothing, which, in turn, increases the rate of heat loss. It is estimated that twenty to fifty percent of hypothermia related deaths are due to paradoxical undressing.
Why does this happen?
Friday, March 10, 2017
Fact of the day: Psychosomatic symptoms love to travel
Hey Awesomites
Yes, you read it right. The symptoms of psychosomatic disorders flit from one body part to another, and just too easily and quickly ( they love to travel a lot ;p ) . Just as one symptom is discovered, it disappears and another one emerges in some other part of the body.
The psychosomatic symptoms have been linked to a chameleon. Every time a medicine tries to pin them down, they become something different.
That's all
- Jaskunwar Singh
The colours of a chameleon are not more numerous and inconstant than the varieties of the hypochondriac and hysteric disease.
- Robert Whytt
NYHA Classification Mnemonic
Hey guys, this post will help you to remember the definitions of the four NYHA classes.
So first just remember two phrases-
"Patient with a heart disease" and "in ordinary or accustomed activities". For convenience I will use letters A and B to refer to these phrases respectively. Now I will just fill in the gap between them.
1. NYHA Class I:
A--- will not get dyspnea ---B.
2. NYHA Class II:
A--- will get dyspnea ---B.
3. NYHA Class III:
A--- will get dyspnea in less than ---B.
4. NYHA Class IV:
A--- will get dyspnea at rest.
This system of classification has its flaws since the definition of "ordinary and accustomed activities" is entirely subjective. Like for example if a rich businessman gets breathless after walking 1 km, you may label him as NYHA Class II, but the same case in a hard working labourer will have to be labelled as NYHA Class III.
And another thing that NYHA has recently clarified NYHA Class III a bit further, it has included self-care activities in it's spectrum. As a supposition, if a 56 year old male person gets breathless while shaving or bathing then it is NYHA Class III.
-VM
Authors' diary: Medicowesome secret project
We initially introduced the secret project very mysteriously and kept the details highly confidential just for fun! Let me tell you more about it...
Thursday, March 9, 2017
Grave's ophthalmopathy features mnemonic
Hey Awesomites
Grave's disease, a common cause of primary hyperthyroidism causes some epic features of ophthalmopathy apart from lid retraction and lid lag. Mnemonic: EPIC
E- Exophthalmos
P- Periorbital Edema
I- Involvement of ocular muscles (diplopia)
C- Conjunctival irritation and chemosis
- Jaskunwar Singh
Grave's disease, a common cause of primary hyperthyroidism causes some epic features of ophthalmopathy apart from lid retraction and lid lag. Mnemonic: EPIC
E- Exophthalmos
P- Periorbital Edema
I- Involvement of ocular muscles (diplopia)
C- Conjunctival irritation and chemosis
- Jaskunwar Singh
Amiodarone- induced thyroid dysfunctions
Hello
Amiodarone, a potent class III anti- arrhythmic drug is contraindicated in thyroid patients or those with subclinical disease. The reason lies in the pharmacokinetic profile of this drug.
The drug has a structural resemblance to triiodothyronine (T3) and thyroxine (T4). In the body, it is metabolized by dealkylation to Desethylamiodarone (DEA), the intrathyroidal concentration of which is higher than the parent drug.
Normal daily recommended intake of iodine for adults is approx. 0.15mg (150mcg). Each 200mg tablet of amiodarone contains about 74.4mg of iodine with 7.4mg (10%) being released as free form. This is roughly 50- fold higher than the normal. Therefore, total body stores may remain increased for upto 9 months after stopping the drug.
High iodine content of this drug inhibits local type-1 5'- deiodinase activity (blocking conversion of T4 to T3) and type- II 5'- deiodinase activity in the pituitary. As a result, TSH is increased initially (mild elevation) and then return to normal or may even decrease in euthyroid patients after weeks, while T4 is normal or raised, and T3 levels decrease.
The increased delivery and uptake of iodine by the thyroid gland may cause increase in hormone production and release, a condition called type-1 Amiodarone- induced thyrotoxicosis (AIT) . In other cases, excessive thyroid tissue destruction due to destructive thyroiditis may lead to type-2 Amiodarone- induced thyrotoxicosis. These are hyperthyroid states!!
Discontinuation of the drug is recommended, if not, then high doses of thioamides and corticosteroids may work in AITs.
Amiodarone may also cause hypothyroidism (AIH) in patients depending upon the iodine status of individuals and prior thyroid disease. Wolff- chaikoff effect is shown by thyroid cells due to failure of thyroid hormonogenesis. Levothyroxine is the drug of choice.
Thats all
- Jaskunwar Singh
Amiodarone, a potent class III anti- arrhythmic drug is contraindicated in thyroid patients or those with subclinical disease. The reason lies in the pharmacokinetic profile of this drug.
The drug has a structural resemblance to triiodothyronine (T3) and thyroxine (T4). In the body, it is metabolized by dealkylation to Desethylamiodarone (DEA), the intrathyroidal concentration of which is higher than the parent drug.
Normal daily recommended intake of iodine for adults is approx. 0.15mg (150mcg). Each 200mg tablet of amiodarone contains about 74.4mg of iodine with 7.4mg (10%) being released as free form. This is roughly 50- fold higher than the normal. Therefore, total body stores may remain increased for upto 9 months after stopping the drug.
High iodine content of this drug inhibits local type-1 5'- deiodinase activity (blocking conversion of T4 to T3) and type- II 5'- deiodinase activity in the pituitary. As a result, TSH is increased initially (mild elevation) and then return to normal or may even decrease in euthyroid patients after weeks, while T4 is normal or raised, and T3 levels decrease.
The increased delivery and uptake of iodine by the thyroid gland may cause increase in hormone production and release, a condition called type-1 Amiodarone- induced thyrotoxicosis (AIT) . In other cases, excessive thyroid tissue destruction due to destructive thyroiditis may lead to type-2 Amiodarone- induced thyrotoxicosis. These are hyperthyroid states!!
Discontinuation of the drug is recommended, if not, then high doses of thioamides and corticosteroids may work in AITs.
Amiodarone may also cause hypothyroidism (AIH) in patients depending upon the iodine status of individuals and prior thyroid disease. Wolff- chaikoff effect is shown by thyroid cells due to failure of thyroid hormonogenesis. Levothyroxine is the drug of choice.
Thats all
- Jaskunwar Singh
Wednesday, March 8, 2017
Fact of the day: Burning the heart to ashes
An interesting fact about heart I read today:
The heart is resilient, literally. When a body is burnt, the heart is the last organ to oxidize. While the rest of the body can catch flame like a polyester sheet on campfire, it takes hours to burn the heart to ash because it's deep inside!
That's all!
Did you know? According to Hindu mythology, when Arjuna cremated the body of Lord Krishna, his whole body turned into ashes, except his heart which was still burning. Arjuna washed the ashes and burning heart into the river.
- Jaskunwar Singh
Munchausen's syndrome
Hello
"Psychosomatic disorders are conditions in which a person suffers from significant physical symptoms (causing real distress and disability), that is out of proportion to that which can be explained by medical tests and physical examinations."
Karl Friedrich Von Munchausen, the "Baron of Lies" gave his name to the syndrome. Munchausen's syndrome (now more correctly called factitious disorder in DSM- 5 classification of somatic symptom and related disorders ) refers to patients who imitate illness (may be in an exaggerated form ) for medical attention and care and may even expose themselves to life- threatening operations, amputations, unnecessary medications and toxic treatments.
Lets take an example: A woman presents to hospital with a headache and a dilated pupil. On investigations, scans were normal and no other systemic abnormality seen. Then, a nurse walks into her room and finds the patient self- administering dilating eye drops into the affected eye.
The person has an awareness of the lies they are telling but they surely do it to seek medical care and attention, being unaware of their own motivation and uncontrolled behavior.
Upto one- third of patients in neurology ward suffer from psychosomatic illness and most often, an emotional cause is suspected.
Thats all
- Jaskunwar Singh
"Psychosomatic disorders are conditions in which a person suffers from significant physical symptoms (causing real distress and disability), that is out of proportion to that which can be explained by medical tests and physical examinations."
Karl Friedrich Von Munchausen, the "Baron of Lies" gave his name to the syndrome. Munchausen's syndrome (now more correctly called factitious disorder in DSM- 5 classification of somatic symptom and related disorders ) refers to patients who imitate illness (may be in an exaggerated form ) for medical attention and care and may even expose themselves to life- threatening operations, amputations, unnecessary medications and toxic treatments.
Lets take an example: A woman presents to hospital with a headache and a dilated pupil. On investigations, scans were normal and no other systemic abnormality seen. Then, a nurse walks into her room and finds the patient self- administering dilating eye drops into the affected eye.
The person has an awareness of the lies they are telling but they surely do it to seek medical care and attention, being unaware of their own motivation and uncontrolled behavior.
Upto one- third of patients in neurology ward suffer from psychosomatic illness and most often, an emotional cause is suspected.
Thats all
- Jaskunwar Singh
Is it okay to wish a man "Happy Women's Day"?
Hello awesomites!
Happy women's day to everyone - Male and female!
Happy women's day to everyone - Male and female!
Tuesday, March 7, 2017
Study group discussion: PGE and congenital heart diseases
We had a discussion on this question on our study group today :)
PGE causes clinical worsening in an infant with?
A. PS without VSD
B. Hypoplastic left heart syndrome
C. Obstructive TAPVC
D. Obstruction in Aorta
Let's work this out - choice by choice!
PGE causes clinical worsening in an infant with?
A. PS without VSD
B. Hypoplastic left heart syndrome
C. Obstructive TAPVC
D. Obstruction in Aorta
Let's work this out - choice by choice!
Asbestosis and Silicosis mnemonics
Here are a few mnemonics to help you not mix these conditions up!
Monday, March 6, 2017
Hyperthermia in Pontine Haemorrhage
Hey guys!
This post will be focused on the pathophysiology of Hyperthermia in Pontine Haemorrhage( which may manifest as the Locked-in Syndrome, remember that super-awesome House episode? <3 )
1. First try the easy simple reason. Hypothalamus has been basically cut off from the body below pons and there has been Haemorrhage. Therefore, there will be a Sympathetic outflow causing peripheral vasoconstriction. Meanwhile the internal visceral organs are still functioning and consequently producing heat. So without hypothalamus, the body's ability to produce heat has transcended it's ability to lose heat.
2. The next reason is a bit "cooler", literally. Our body hates Hypothermia more than Hyperthermia, thanks to evolution. (Ice Age!!!) Now there is no central thermoregulation but peripheral one is still intact. And the peripheral thermoreceptors are much more sensitive to lower temperatures or basically cold environment. Once again, without the Hypothalamus, the body is defending itself too vigorously against Hypothermia as to contribute ironically to Hyperthermia.
3. This reason is the only one which you should know since this will explain how Baclofen, a GABA-B Agonist works to treat this Hyperthermia. Remember the Medial Forebrain Bundle, it connects Hypothalamus to a lot of structures, one of them being Nucleus Raphe in the Pontine reticular formation. This is a very crucial portal in control of Sympathetic nervous system outflow by Hypothalamus. Simply speaking, if the body is hot, Hypothalamus will send inhibitory (GABAergic and Dopaminergic) signals to this nucleus and if the body is cold, it will send excitatory (Glutaminergic and Serotonergic) signals. And apparently this connection is lost in Pontine Haemorrhage, so we substitute it with a drug.
P.S. Now you can guess how Bromocriptine and Apomorphine cause Hypothermia. :)
-VM
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