Of Surgery and Wounds

Hey guys, here’s a classification of surgical procedures, wounds and their infection risk.

[Please click on the image to enhance it]

Thank you for your time.
- Ashish Singh.

What Is Going On In Fibromyalgia?

Hi there! Let’s talk about pathophysiology of fibromyalgia; a chronic disorder where fatigue and widespread pain feature prominently.

Current hypothesis says, it’s caused by aberrant peripheral and central pain processing.
Two key features are allodynia, that is, pain in response to a non-painful stimulus and hyperaesthesia, which is, exaggerated perception of pain in response to mildly painful stimulus.

Modern research says, certain antidepressants- with both serotonergic and noradrenergic activity- such as TCAs and venlafaxine, can relieve pain and other symptoms; suggesting the pathway involvement.

Some evidence says, alternative therapies such as acupuncture and spa therapies alleviate pain, which have been postulated to act via similar spinal pain-modulatory pathways.

CSF studies show increased levels of substance P, with decreased levels of noradrenaline and serotonin metabolites. All three are neurotransmitters involved in descending pain-modulatory pathways in the spinal cord.

PET images show an abnormal central dopamine response to pain.

The critical question here is: what is cause and what is effect?

Small sample size and short periods of study, remain the most cumbersome challenge to our complete understanding of fibromyalgia.  



Thank you for reading.
- Ashish Singh.

Mnemonic: Duke’s Criteria for Infective Endocarditis

Infective endocarditis is diagnosed using the modified Duke’s criteria.
Let’s look at them in an easy-to-remember way.

MAJOR CRITERIA
It’s, quite literally, proving the name Infective Endocarditis to be true.

Infective, that is, positive blood culture:
• Typical bugs in 2 separate cultures
• Persistently positive blood cultures, say > 12h apart
• Single positive blood culture for Coxiella burnetii

Endocarditis, that is, endocardium involvement:
• On imaging with 2D Echo or CT, look for vegetation, abscess, pseudoaneurysm or dehiscence of prosthetic valve
• On clinical exam, find new regurgitation murmur

MINOR CRITERIA
Remember, patients feel very ill when they have infective endocarditis.
Predisposing factors: congenital heart disease, prosthetic heart valves, iv drug abuse
Fever > 38 °C
Vascular phenomena: emboli, Janeway’s lesions
Immunologic phenomena: glomerulonephritis, Osler’s nodes

What if the blood culture is positive but does not meet the major criteria?
It’s considered as a minor criterion (casually speaking, problematic but not majorly problematic).

How do we use this for diagnosing?
2 major OR
1 major + 3 minor OR
All 5 minor criteria, make up the diagnosis.

Clinical Pearl: Fever with any new-onset murmur is taken as infective endocarditis, unless proven otherwise.



Hope this helps. Happy studying!
- Ashish Singh.

CABG For Undergraduates

CABG is Coronary Artery Bypass Graft; a surgical procedure where dying heart muscle is resupplied with blood.

Indications
[decided after a SYNTAX scoring system]
• Left main stem disease
• Triple-vessel disease involving proximal left anterior descending
• Patients unsuitable for angioplasty 
• Failed angioplasty
• Refractory angina

Procedure
• The heart is usually stopped and blood pumped artificially by a machine outside the body, a cardiac bypass. An alternative, that does not require this, is minimally invasive thoracotomy.
• As the graft, patient’s own great saphenous vein, internal mammary artery or radial artery is used. Multiple grafts may be placed. Arterial grafts last longer but may cause donor site numbness.

After CABG
• Continue aspirin 75 mg/day indefinitely. Consider clopidogrel, if aspirin contraindicated.
• Ensure optimal management of hypertension, diabetes and dyslipidemia.
• Counsel for smoking and alcohol cessation.
• Chart out graded physical activity through rehabilitation.
• Uncommonly, angina may persist or recur [from poor graft run-off, distal disease, new atheroma or graft occlusion]. If so, restart anti-anginal drugs and consider angioplasty.

Clinical Pearl: Recent randomised control trials indicate that early procedural mortality rates and 5-year survival rates are similar after PCI and CABG.



Thank you for reading.
- Ashish Singh.

Understanding Refeeding Syndrome

Refeeding syndrome is a life-threatening metabolic complication of - stay with me - refeeding. It can happen via any route after prolonged starvation.

Who are at risk?

They’re patients with prolonged artifical feeding [parenteral or enteral], malignancy, anorexia and alcoholism.

Why does it happen?

During starvation, the body uses fat and protein for energy. There’s no carbs so there’s little to no insulin.

After refeeding, carbohydrate load causes a spike in insulin level.

Now first prof biochemistry tells you, more insulin means more cellular uptake of phosphate.

That’s it. That low serum phosphate level is the main problem.

How does it present?

Non-specifically and catastrophically. Features are rhabdomyolysis, red and white blood cell dysfunction, respiratory insufficiency, cardiac arrhythmias and seizures.

Left unchecked, it can lead to sudden death.

How do I prevent it?

Identify at-risk patients and give high-dose, high-potency Vitamin C and B complex injection, during re-feeding window.

Monitor vitals and labs closely. Close involvement of nutritionist is ideal.

What if it’s already happened? How do I treat it?

The biggest challenge is management of complications.

As regards phosphate, get the levels back up. Administer oral as well as parenteral phosphate, upto 18 mmol per day.

Thank you, that’d be all.

- Ashish Singh.

What are APS?

APS or Autoimmune Polyendocrine Syndromes are exactly what the name suggests.
They’re autoimmune in origin and they attack more than one endocrine system.

[Please click on the image to enhance it]

Let’s not forget autoimmunity begets autoimmunity.

APS are commonly seen with hypogonadism, vitiligo, alopecia, pernicious anaemia and coeliac disease, among others.

That’d be all. Happy studying!

- Ashish Singh.

PR depression in pericarditis

Do you know what P-R segment deviations in acute pericarditis mean?

It is due to subepicardial atrial injury!

Residency in India: Harassment, abuse and suicide

A few days ago, a resident committed suicide. One of us committed suicide.

In my opinion, it seems like the reason for the suicide was harassment, abuse, and excessive work load. If you ask any resident in any government hospital in Mumbai - they are all treated the same. The verbal abuse is probably different - They used casteist slurs for her. If you are privileged, they will call you different names.

How can we make sure this never happens again? Stop carrying forward the culture of abuse. It is high time. We have to fight the system. The past. The belief that it is okay just because it's residency. Don't look at how our seniors treated us but look at how we treat our juniors.

We need to treat each other better. Treat others how you would like to be treated yourself.

We need to help each other.

It is our fault that the life of an innocent was lost. It's because we didn't fight and we stayed silent when we saw abuse around us. We need to create awareness among medical students that will be joining residency. Let's talk about the abuse and how we can stop it. Residents should know who to report to without fear of negative consequences.

It will take time and it will probably not change in a day. But we are the future and we need to fight.

Fundoscopic images of Diabetic Retinopathy

Fundoscopic images of Diabetic Retinopathy

Images and audio by Sushrut.

Indications of skin grafting mnemonic + notes

Hello,

Indications of skin grafting :

☆ Mnemonic - BITS

Sites of Bronchiectasis

Bronchiectasis site in lung depends upon the etiological factors

Upper lobe bronchiectasis:

Mnemonic: Upper - PCT
Upper- Upper lobe
P- Post radiation
C- Cystic fibrosis
T- Tuberculosis

Middle lobe bronchiectasis:

Mnemonic: MMC (Like BMC!)
M- Middle lobe
M- Mycobacterium avium
C- Ciliary dyskinesia

Lower lobe bronchiectasis:

Mnemonic: Left-ICA (Internal carotid artery)
Left- Lower lobe
I- Interstitial lung disease
CA- Chronic aspiration

That's all.
Thank you :)

-Demotional bloke

History, physiology and medical aspects of fasting

Hello everyone,

My senior resident at JFK Medical Center did a presentation on fasting. I thought of sharing it with you (especially since it is Ramazan/Ramadan).

Hook effect of prolactin in large pituitary adenomas

Hello everyone,

Here's something I learnt today when a case of large pituitary adenoma causing visual field loss was presented today.

But let's talk about my favorite subject first - Immunology!

The intensity of an antigen-antibody interaction depends primarily on the relative proportion of the antigen and the antibody. A relative excess of either will impair adequate immune complex formation. This is called the “high-dose hook effect” or the “prozone phenomenon.”

This is important consideration whe measuring prolactin. Extremely high levels of prolactin can interfere with the assay and produce falsely low readings.

This high-dose hook effect occurs because there is not enough antibody to bind to both ends of all antigenic peptides, in this case, prolactin.

Most prolactin is complexed to a single antibody. Only few remaining prolactin peptides are “sandwiched” and therefore detectable.

This results in a falsely low prolactin value.

Hence, as the antigen concentrations increase, there is a proportional increase in assay titers up to a certain level. Antigen concentrations above this threshold level would “hook” down the assay values resulting in very low measurements.

In order to avoid the high-dose hook effect, the serum prolactin should be estimated in appropriate dilution in all patients with large pituitary tumors.

-IkaN (tired Internal Medicine Resident)

Source:
The 'hook effect' on serum prolactin estimation in a patient with macroprolactinoma. https://www.ncbi.nlm.nih.gov/m/pubmed/11303248/

Protein gap

The gamma gap aka paraprotein gap or protein gap is the difference between total serum proteins and albumin measured from a comprehensive metabolic panel.

Albumin accounts for the majority of total serum protein.

Viral infections, plasma cell malignancies, or autoimmune conditions there is an excess of immunoglobulins, raising the total amount of serum protein independent of albumin.

The gamma gap is typically considered to be elevated if it is above 4 g/dL.

In the right clinical context, gamma gap should be worked up with SPEP, UPEP, and a serum free light chain assay.

Random exercise: Calculate the protein gap.
Total protein 8.9 g/dL (normal 6.4-8.3 g/dL)
Albumin is 3.6 g/dL (normal 3.4-4.8 g/dL)

That's all!

-IkaN

Work up of thyroid nodule

Hello,

Here is the shorter version of this post: Investigating thyroid nodule for Step 2 CK (link: https://www.medicowesome.com/2016/06/step-2-ck-investigating-thyroid-nodule.html)

So - if you find a thyroid nodule on physical examination - what do you do next?

Caudal anaesthesia

Hello Awesomites!

Caudal anesthesia is a type of epidural anesthesia. 

INDICATIONS
The indications for single shot CA are abdominal,urologic or orthopedic surgical procedures located in the sub-umbilical abdominal, pelvic and genital areas, or the lower limbs, where postoperative pain does not require prolonged strong analgesia. Examples include inguinal or umbilical herniorrhaphy, orchidopexy, hypospadias and club foot surgery.

Anatomical landmarks (Figure)
The sacrum is roughly the shape of an equilateral triangle,with its base identified by feeling the two
posterosuperior iliac processes and a caudal summit corresponding to the sacral hiatus.The sacral hiatus is located at the caudal end of the median crest and is created by failure of the S5 laminae
to fuse (Figure). The hiatus is surrounded by the sacral cornu.

Preparation
Obtain consent for the procedure either from the patient or, if appropriate, from the parents. After induction of general anaesthesia and airway control, the patient is positioned laterally (or ventrally),
with their hips flexed to 90°. Skin disinfection should be performed carefully, because of the proximity to the anus.
After defining the bony landmarks of the sacral triangle, the two sacral cornuae are identified by moving your fingertips from side to side.The gluteal cleft is not a reliable mark of the midline. The puncture is performed between the two sacral cornuae. The needle is oriented 60° in relation to back plane, 90° to skin surface. The needle bevel is oriented ventrally, or parallel to the fibers of the sacro-coccygeal ligament.
After verifying absence of spontaneous reflux of blood or cerebrospinal fluid (more sensitive than an aspiration test), injection of LA should be possible be without resistance. Inject slowly (over about one minute).

-Upasana Y. :) 

HbA1c and Estimated Average Glucose

Hello Awesomites!

Sounds new. Wait till the end!

Do You know what is HBA1c?

HbA1c is produced by the condensation of Glucose with N-terminal valine of each beta chain of HbA.

Diagnostic importance
The rate of synthesis of HBA1c is proportional to exposure of RBC to glucose. Concentration of HBA1c is indication of blood glucose concentration.
It reflect mean blood Glucose level over 2-3 months prior to its measurement.If HbA1c is <7% then diabetes is in good control. To get an accurate result the concentration should be monitored for several months.

Estimated average glucose (eAG) :- It is new term in diabetic management.It helps to interpret HbA1c levels into average glucose concentration.
eAG(mg/dl) =(28.7×HbA1c) - 46.7

Drawback
The A1c doesn’t replace self blood-glucose monitoring. Because the A1c is an average of all your blood sugars, it does not tell you your blood sugar patterns. If someone has certain type of hemoglobin mutations (variation in the hemoglobin structure) (HbA1c is falsely low) , is severely anemic (low red blood cell count), iron deficient( HbA1c is falsely high) or is being treated blood transfusions or medications to increase the production of new red blood cells, the A1c test may not be accurate.

Thank you.
Upasana Y. :)

Diabetic Retinopathy

Here is Upasanas video on Diabetic Retinopathy.

I edited the slides so you can see better :)

Slides are available for download here:

PARTNER 3 trial journal club

Hey everyone!

A few months ago, I did a journal club on the PARTNER 3 trial.

I have been meaning to create an audio file and upload the whole journal club as a video on YouTube but unfortunately, I don't seem to have the time.

This is why, I decided to go ahead and release my slides instead so it helps anyone who is doing a journal club on the same :)

Oblique muscle mnemonic

It can be hard to remember which oblique does what. Remember this. 'Extortion' as we all know is forcing money out of someone. People from the 'inferior' strata of the society extort money. See where am I  going?!

So! Inferior oblique causes extorsion( 'extortion' is a bit different- c'mon, be a grammar Nazi!)
What remains? Superior oblique. So..it then is responsible for intorsion.

Similar is the case for superior and inferior recti.

Hope I saved you from ophthalm extorting your precious time.

-Sushrut

Cardiovascular changes in pregnancy

At term
- Blood volume increases by 50%
- increased uterine blood flow 500-800ml/min
- uterus recieves 10-15% cardiac output