Thursday, December 31, 2020
Thursday, December 24, 2020
The three O's of GI bleeding : Overt, obscure, and occult
Sunday, December 20, 2020
The BNT162b2 Covid-19 Vaccine: Pfizer-BioNTech Vaccine
The BNT162b2 mRNA Covid-19 vaccine, popularly known as the
Pfizer vaccine is the first Covid-19 vaccine to receive authorization for use
in the general public. The first jab was given to a 90-year old lady in the UK on December 8, 2020; a monumental event that brought hope to billions of people all across
the globe. In this article, I will discuss this vaccine’s clinical trial and potential
future implications.
How does it act?
The BNT162B2 is a lipid nanoparticle-formulated,
nucleoside-modified mRNA that encodes the SARS-CoV-2 full-length spike protein,
modified by two proline mutations to lock it in the prefusion conformation. This
means that this is an mRNA that has been modified to resist disintegration by
nucleases and that translates into the SARS-CoV-2 spike protein. However, this
spike protein has also been modified to lock it into its pre-fusion
conformation; so that it doesn’t fuse with the target cell’s plasma membrane and
remain exposed to immunogenic stimulation.
Who is it for?
This primarily depends on the characteristics of the population
included in the vaccine’s clinical trial. This trial randomised 43,458 persons
from six countries: USA, Argentina, Brazil, South Africa, Germany, and Turkey. More
than three-fourth of the study population (76.7%) belonged to the USA. Moving
on to the representation of race or ethnicity in the study population - 82.9% were
white, 27.9% were Hispanic, while African Americans, Asians, and Native
Americans comprised 9.2%, 4.2%, and 0.5% of the study group. Males and females
were almost equally included. The age range is from 16 years to 89 years in the
intervention group. This trial did not evaluate the efficacy of the vaccine in
children, adolescents, and pregnant women.
Is it effective?
Define effective; it depends on the trial’s efficacy end
points. The primary endpoint was the efficacy of the vaccine to prevent Covid-19
infection 7 days after the second dose in participants who had no serologic
(antigen and antibodies) or virologic (RT-PCR) evidence of SARS-CoV-2 infection
up to 7 days after the second dose; the second primary endpoint was to prevent
infection in those with and without evidence of prior infection. Confirmed
Covid-19 was defined as – the presence of at least one symptom (fever, new or
worsened cough, new or worsened dyspnoea, chills, new or worsened muscle pain,
new loss of taste or smell, sore throat, diarrhoea or vomiting combined with a positive
RT-PCR test within 4 days).
Efficacy End Point |
BNT162b2 Group |
Placebo Group |
Vaccine efficacy, % (95% credible interval) |
||
Covid-19 Cases |
N |
Covid-19 Cases |
N |
||
1st Primary |
8 |
18,198 |
162 |
18,325 |
95(90.3-97.6) |
2nd Primary |
9 |
19,965 |
169 |
20,172 |
94.6(89.9-97.3 |
However, the trial results did not show the efficacy in
preventing asymptomatic infection. We don’t know if this vaccine can safeguard
against transmissible asymptomatic infection; therefore, people who have taken
the vaccine should not stop wearing masks for the sake of the people around
them.
Is it safe?
The vaccine group reported more local reactions, such as
pain, redness, and swelling at the injection site than the placebo group. In
general, these were mild-to-moderate in severity and resolved within 1-2 days.
The systemic adverse effects were also reported more in the intervention group,
especially in the younger population (16 to 55 years of age), and more after
the second dose. These included – fever (11%), fatigue (51%), headache (39%),
chills (23%), muscle pain (29%), joint pain (19%), and 38% of the vaccine group
needed to use antipyretic medication. These were generally mild and resolved
within 1-2 days. Two deaths happened in the vaccine group, one from
arteriosclerosis, and one from cardiac arrest. These deaths weren’t related to
the vaccine or Covid-19. The investigators plan to continue the surveillance
for adverse events for further 2 years.
This study has importance beyond the efficacy of the
BNT162b2 vaccine candidate. It demonstrates the utility of RNA-based vaccines, its
speed of development, and its promising efficacy in preventing infectious
diseases. The success of this clinical trial immensely improves our preparedness
for a future pandemic.
Reference:
Polack, FP, et al. Safety and Efficacy of the BNT162b2 mRNA Covid-19 Vaccine. New England Journal of Medicine. Dec 10, 2020. 10.1056/NEJMoa2034577. C4591001 Clinical Trial group
-Vinayak
Thursday, December 17, 2020
All mnemonics for how to determine axis deviation of EKG
Hello Everybody!
Before reading this post I would like to suggest please see both the videos of How to determine axis deviation in real scenarios... Then come back here for summary & some extra mnemonics.
Hope it’ll definitely helps you!
How to remember numbers...?
“Isoelectric Method”
Wednesday, December 16, 2020
Types of Left Ventricular Hypertrophy (LVH)
Tuesday, December 15, 2020
COVID-19 Vaccine Development
The worldwide magnitude of the COVID-19 pandemic is ineffable; it is unsurprisingly compared to the Spanish flu pandemic, which ravaged the world during the First World War (adding fuel to the fire!). One of the pandemic's various positive impacts has been the unprecedented research collaboration and data sharing across the world. Such singular efforts made it possible to cut down the usual time to achieve an approved vaccine from 10+ years to less than a year.
To put things into perspective, it took 60 years from the
time of the first polio outbreak to developing its vaccine; in the case of
Ebola, it took 15 years. Vaccine candidates for SARS-CoV-1 and MERS did not receive
the necessary impetus to advance into fruition. However, with SARS-CoV-2, the
situation is very different. Global initiatives such as ACTIV (Accelerating
COVID-19 Therapeutic Interventions and Vaccines), a public-private partnership
comprising of bigwigs like CDC, FDA, EMA (European Medicines Agency), and
numerous leading biopharmaceutical enterprises. Another project on a similar
scale is Operation Warp Speed, which has invited comparison to the infamous
Manhattan Project.
What is an "ideal" COVID-19 vaccine? There are
three criteria from the immunological perspective: 1) It induces a robust humoral
immune response that produces long-lasting neutralizing antibodies against
SARS-CoV-2 antigens, 2) It generates a strong cell-mediated immunity that
includes the production of memory T cells, 3) It should be free of any serious
local or systemic adverse effects. Considering the logistics of vaccinating the entire world, there are three more criteria: 1) It should be easy to administer,
preferably in one or two doses, 2) It should be easy to produce on a
large-scale, 3) Its storage should be uncomplicated, ideally possible at room
temperature.
Let us discuss the vaccines that are currently in
development. We all have heard about a few of them in the news and social media,
namely, Pfizer, Moderna, Covaxin, Astra Zeneca, and so on. There are,
impressively, 125+ SARS-CoV-2 vaccines in development globally. Broadly,
there are six platforms currently being utilized for vaccine development –
3. Protein (Subunit vaccines)
4. Viral vector – replicating/non-replicating
(examples - Oxford/Astra Zeneca, Johnson & Johnson)
5. Live attenuated virus
6. Inactivated virus
Almost all of the above models have targeted the spike glycoprotein,
which is present on the surface of SARS-CoV-2, to interfere with the viral
entry into a cell.
This article is an oversimplified summary of the vaccine development process. I haven't covered the vaccine platforms, molecular targets, and vaccine candidates in detail. With the advent of vaccine administration, whether it's Pfizer's or any other, there will be a massive surge in vaccine-related information. There will be challenges at every step, from distribution to underdeveloped areas of the world to alleviate the concerns of the skeptical anti-vaxxers. Let us hope that these vaccines start the end of the pandemic.
-Vinayak
Sunday, December 13, 2020
Saturday, December 12, 2020
About the Pfizer BioNTech COVID-19 Vaccine trial
Emoticon game: Acute Liver Failure answers
COVID-19 and the increased risk of Parkinson's disease
Hi!
Currently posted in psychiatry, I was reading articles on Parkinson's disease and came through this important finding in context with the coronavirus disease.
Friday, December 11, 2020
Cosmetic surgery and Nontuberculous Mycobacterial infections
Conus medullaris syndrome vs. Cauda equina syndrome
Both of these are orthopedic/neurosurgical emergencies! But in general, CM syndrome is more severe than CE syndrome.
Here's a comparison between the two...
Guidelines for management of gout by ACR 2020
Hi!
Long time..
Urate-lowering therapy indications and important guidelines for management of gout, as updated by ACR in 2020:
Monday, December 7, 2020
TORCH syndrome + mnemonic
TORCH syndrome is caused by congenital infection by a group of infectious agents.
Respiratory fluoroquinolones
Why are moxifloxacin, gemifloxacin, and levofloxacin also known as respiratory fluoroquinolones?
Sunday, December 6, 2020
Saturday, December 5, 2020
Mechanical ventilation
Terms you need to know
1.
PaO2: Oxygen saturation in arterial blood (N = 80-100)
2.
PaCO2: Carbon Dioxide saturation in arterial
blood (N = 35 – 45)
3. FiO2: Fraction of inhaled O2 (N = 21% i.e. the fraction of O2 in atmosphere air which we inhale)
4.
PEEP: Positive End Expiratory Pressure – The pressure needed at the end of expiration to keep the alveoli open.
5.
RR: Respiratory rate (N = 12-16)
6. TV: Tidal Volume (N = 6-8 ml/kg = approx. 500 ml)
Thursday, November 26, 2020
Thursday, November 19, 2020
When should you start sodium bicarbonate in CKD patients? Mnemonic
Monday, November 16, 2020
Neurology examination template
Here is my template for documenting the basic bare minimum neurology examination.
Saturday, November 7, 2020
It's a Carny Problem
Carney's Triad - ENCHONDROMA + PARAADRENAL GANGLIOMA + GIST
Friday, November 6, 2020
Blood Donation
BLOOD DONATION
PRE-DONATION
HISTORY:
- Men can donate safely once every three months while women can donate every four months
- Age between 18 and 60 years
- The donor should be in a healthy state of mind and body
- Past one year - not been treated for Rabies or received Hepatitis B immune globulin
- Past six months - not had a tattoo, ear or skin piercing or acupuncture, not received blood or blood products, no serious illness or major surgery, no contact with a person with hepatitis or yellow jaundice.
- Past three months - not donated blood or been treated for Malaria
- Past one month - had any immunizations
- Past 72 hours - had dental work or taken Aspirin
- Past 48 hours - taken any antibiotics or any other medications (Allopathic or Ayurveda or Siddha or Homeopathy)
- Past 24 hours - taken alcoholic beverages
- Presently - not suffering from cough, influenza or sore throat, the common cold
- Women should not be pregnant or breastfeeding her child or menstruating.
- No diabetes, chest pain, heart disease or high BP, cancer, blood clotting problem or blood disease, unexplained fever weight loss, fatigue, night sweats, enlarged lymph nodes in armpits, neck or groin, white patches in the mouth, etc.
- No history of TB, bronchial asthma or allergic disorder, liver disease, kidney disease, fits or fainting, blue or purple spots on the skin or mucous membranes, received human pituitary - growth hormones, etc.
EXAMINATION:
- Temperature - Normal (oral temperature not exceeding 37.50 C)
- Pulse - between 50 and 100/minute with no irregularities
- Blood Pressure -Systolic 100-180 mm Hg and Diastolic 50 - 100 mm Hg
- Bodyweight - not less than 45 Kg
- Hemoglobin - not less than 12.5 g/dL-
Procedure to measure Hb using CuSO4:
i) Massage the finger to be pricked (preferably ring finger)
ii) Disinfect it
iii) Prick using disposable needle/ lancet
iv) Put the drop of blood in CuSO4 containing beaker
v) If the blood drop sinks, Hb is more than 12.5, hence the person can donate blood (provided no other contraindication).
PROCEDURE:
- Identify donor and label blood collection bag and test tubes
- Ask the donor to state their full name
- Ensure that:
- the blood collection bag is of the correct type;
- the labels on the blood collection bag and all its satellite bags, sample tubes and donor records have the correct patient name and number;
- the information on the labels matches with the donor's information
- Select a large, firm vein, preferably in the antecubital fossa, from an area free from skin lesions or scars
- Clean the site of venepuncture by alcohol and let it dry
- Perform phlebotomy using a 16-gauge needle, which is usually attached to the blood collection bag. Use of a retractable needle or safety needle with a needle cover is preferred if available, but all should be cut off at the end of the procedure.
- Ask the donor to open and close the fist slowly every 10–12 seconds during collection
- Remove the tourniquet when the blood flow is established or after 2 minutes, whichever comes first
- Ask the patient to squeeze a ball intermittently during the procedure
- Monitor the donor and the donated unit
- Remove the needle and collect samples
- Cut off the needle using a sterile pair of scissors
- Collect blood samples for laboratory testing
POST-PROCEDURE:
DONOR CARE:
- ask the donor to remain in the chair and relax for a few minutes
- inspect the venepuncture site; if it is not bleeding, apply a bandage to the site; if it is bleeding, apply further pressure
- ask the donor to sit up slowly and ask how the person is feeling
- before the donor leaves the donation room, ensure that the person can stand up without dizziness and without a drop in blood pressure
- offer the donor some refreshments
BLOOD UNIT AND SAMPLES:
- Transfer the blood unit to a proper storage container according to the blood center requirements and the product
- Ensure that collected blood samples are stored and delivered to the laboratory with completed documentation, at the recommended temperature, and in a leakproof, closed container
REFERENCES:
http://naco.gov.in/blood-transfusion-services-publications
Written by our guest authors HARSH JOGI and AYUSHI GUPTA
Tuesday, November 3, 2020
Ascitic Tap
Monday, November 2, 2020
USMLE STEP 1: Resources and preparation
Monday, October 26, 2020
CNS practical higher examination function.
GCS Glasgow Coma scale video
Thursday, October 22, 2020
USMLE Step 3 experience (247 score)
Monday, October 19, 2020
Friday, October 16, 2020
Tuesday, October 13, 2020
Sunday, October 11, 2020
About US clinical experience and tips for electives
Saturday, October 10, 2020
Gerstmann's syndrome physical examination
Hoffman sign in neurology
Friday, October 9, 2020
Shingles vaccine
Internship diaries: Perception of nipple discharge
Mechanism of action of lipid-lowering drugs
Ezetimibe inhibits cholesterol absorption from the intestine.
Sunday, October 4, 2020
Sub-specialty WhatsApp groups
I have decided to create sub-specialty groups on WhatsApp in addition to our regular study groups. If more than 5 people are interested in it, we will create a group.
Sunday, September 27, 2020
Friday, September 25, 2020
Sodium-glucose co-transporter 2 (SGLT2) inhibitors notes and mnemonics
Canagliflozin (brand name Invokana)
Empagliflozin (brand name Jardiance)
Dapagliflozin (Farxiga)
Ertugliflozin (Steglatro)
Mnemonic: GliFlozIN makes Glucose Flow In Nephrons
Has beneficial effects on ASCVD events, heart failure, and CKD.
Causes weight loss (Mnemonic: SGLT2 Surely Generates Less Tummy).
No risk of hypoglycemia.
Genital fungal infections.
Fournier’s gangrene.
Dehydration may result.
Euglycemic diabetic ketoacidosis (should be held 24H prior to scheduled surgeries).
Canagliflozin may increase the risk of leg amputation (should be avoided in those with peripheral vascular disease).
-IkaN
Metformin notes and mnemonics
Mechanism:
Decreases hepatic glucose output by reducing hepatic gluconeogenesis and glycogenolysis.
Enhances peripheral glucose uptake and enhances insulin sensitivity.
Decreases glucose absorption in the GI tract.
Reduces hemoglobin A1C levels by 1.5%.
In addition:
Decreases triglyceride levels.
Decreases LDL-cholesterol.
May increase HDL-cholesterol.
Side effects:
Diarrhea
Vitamin B12 deficiency may develop
Risk of lactic acidosis in renal or liver disease or CHF
Contraindicated in: GFR <30ml/min.
That's all!
-IkaN
Related posts:
Oral hypoglycemic drugs used for diabetes mellitus mnemonic: Metformin meets glucose and advises it to stay out of the blood. It asks the liver to keep glucose in the house (Inhibits hepatic glucose production) and asks the glucose in the bloodstream to go into adipose and skeletal muscle (Stimulates peripheral uptake of glucose). Metformin never met a glucose molecule and did not tell him to not stay in the blood (Illustration in the original post).
Oral hypoglycemic drugs and weight - Weight gain or weight loss mnemonic: "Metformin forms you in, makes you thin."
Thursday, September 24, 2020
Interview questions for practice
Here are some of the questions I was asked during my cardiology fellowship interviews. They can be useful to practice during medical school or residency interviews as well, which is why I am writing this post.
How do you answer these questions? Always attach a story (situation) to it. It only comes with practice - so please, practice a lot.
Wednesday, September 23, 2020
Fragmented QRS
Fun fact: Fragmented QRS can be caused by conduction around the scarred myocardium, resulting in multiple spikes within the QRS complex.
-IkaN
Thursday, September 17, 2020
No-reflow or low reflow phenomenon in total coronary artery occlusion
What is the no-reflow or low reflow phenomenon?
If blood flow to the ischemic tissue continues to be impeded after relief of the occlusion.
Why does this happen?
After prolonged cessation of coronary perfusion and restoration of blood flow to the epicardial coronary arteries, structural damage occurs to the microvasculature that prevents the restoration of normal blood flow to the cardiac myocytes. Various mechanisms are implicated in the genesis of the no-reflow phenomenon.
Friday, September 11, 2020
SLC gene Mutations and related Disease
Hello Awesomites!
Enjoy this crisp post on SLC gene mutations.
SLC= Solute carrier
SLC39A4 | Acrodermatitis enteropathica |
SLC26A4 | Pendred |
SLC6A9 | Hartnup disease |
SLC5A2 | Renal glucosuria |
FYI-Diseases associated with SLC6A4 include Anxiety and Obsessive-Compulsive Disorder
For further information read this article SLC transporters as therapeutic targets.
Fact- Reversible ADP-r inhibitors cause breathlessness
Hi
Reversible inhibitors of ADP-r (P2Y12) such as ticagrelor, cangrelor, and elinogrel used as anti-platelet drugs have a unique side effect of dyspnea, unlike the irreversible ones. This is hypothesized to occur because of reversible inhibition of ADP-r on sensory neurons. Since half-life of the reversible inhibitors is shorter than that of irreversibles, repeated doses lead to permanent inhibition of the P2Y12 receptors on sensory neurons.
Moreover, oral administration is found to cause more severe effects on the breathing difficulties than the parenteral route.
Source- Research gate
That's all
- Jaskunwar Singh
Thursday, September 10, 2020
Naegele's formula
- add seven days (i.e 29th)
- subtract 3 months (i.e March)
- add one year (i.e 2020)
Friday, September 4, 2020
Lover's heel
Friday, August 14, 2020
Answer: 17-year-old male presents with confusion and drowsiness
A 17-year-old male presents with confusion and drowsiness for 1 day.
He has been healthy and playing in the high school basketball team for the last 2 years. His practice sessions always included 10 minutes of intense work followed by a period of rest or decreased activity. He also had complaints of dark urine which the previous doctor diagnosed as dehydration and was asked to drink more water.
He recently started a football club and has been playing football in addition to basketball. He has had oliguria for 4 days. Vitals are BP 124/86 mm of Hg, HR 85 b/min. Pupils are non dilated and reactive to light equally bilaterally. The remainder of the physical examination is within normal limits. Lab work shows:
Question: 17-year-old male presents with confusion and drowsiness
A 17-year-old male presents with confusion and drowsiness for 1 day.
He has been healthy and playing in the high school basketball team for the last 2 years. His practice sessions always included 10 minutes of intense work followed by a period of rest or decreased activity. He also had complaints of dark urine which the previous doctor diagnosed as dehydration and was asked to drink more water.
He recently started a football club and has been playing football in addition to basketball. He has had oliguria for 4 days. Vitals are BP 124/86 mm of Hg, HR 85 b/min. Pupils are non dilated and reactive to light equally bilaterally. The remainder of the physical examination is within normal limits. Lab work shows:
Sickle cell retinopathy
What is the hallmark of sickle cell retinopathy?
Sea fan neovascularization.
All patients with SCD should have dilated funduscopic examinations every 1 to 2 years beginning at age 10, preferably by a retina specialist.
Treatment is usually Laser photocoagulation.
Anti-VEGF medications such as bevacizumab or ranibizumab may lead to partial regression of sea-fan neovascularization.
Sickle cell anemic retinopathy is seen mostly in heterozygous S-C trait and S-Thal trait.
Fun fact: Sea fans are beautiful soft corals.
-IkaN