Hot answers tagged

31 votes
Accepted

What is excess blood from blood donations used for, and do we ever run out?

Great question! I think it's answerable as an overview, but please know this is only the tip of the iceberg.* Summary: Yes, we have deficits of certain blood products in certain locations at certain ...
user avatar
  • 4,355
15 votes
Accepted

Risks of blood donation with autoimmune diseases

The World Health Organization published a report entitled Blood Donor Selection: Guidelines on Assessing Donor Suitability for Blood Donation. Based on a review of scientific studies and other ...
user avatar
  • 1,838
13 votes
Accepted

how many 'lives' are saved from one donation of blood?

I think your skepticism may come from not understanding the process behind the claim. A single unit of blood is separated into 4 main "blood products": red blood cells, plasma, platelets, and white ...
user avatar
10 votes
Accepted

Is lipaemia the same as hyperlipidemia?

These are not really synonymous. Despite some sites claiming them to be. Compare the usage on this site. Lipaemia is describing lab artifacts, that is roughly too much fat in the blood sample that ...
user avatar
  • 6,757
9 votes
Accepted

Medical relevance of tetanus vaccination

Clostridium tetani is the causative organism in tetanus. It requires an anaerobic environment to grow so is found in soil and in the gut of animals. Person to person transmission is not possible. ...
user avatar
  • 13.2k
9 votes
Accepted

Why do surgeons wear blue aprons during surgeries?

Initially surgeons did wear white in the operating theater, but there were two large problems with this. Firstly, under the bright lights, the white reflects too much light making an inordinate amount ...
user avatar
  • 104
9 votes

Is lipaemia the same as hyperlipidemia?

Because the context refers to a serum sample, and it sounds like a low quality one, you should use lipemia (or, the british variant lipaemia), not hyperlipidemia. See here for an example of the ...
user avatar
  • 3,153
8 votes
Accepted

Can eating chalk cause very low level haemoglobin level?

Eating chalk is a type of Pica. It is characterized by an appetite for substances that are largely non-nutritive, such as paper, clay, drywall or paint, metal, chalk, soil, glass, or sand which is ...
user avatar
  • 725
8 votes
Accepted

Why does your head get enough blood and your feet don't when lifted above your body?

This is a very good question. The answer: because your head was meant to be above your body! Your body has very specific mechanisms for maintaining a constant blood flow in the cerebral circulation ...
user avatar
  • 4,355
8 votes
Accepted

Does having more muscles influence blood pressure measurement?

There is evidence that a muscular arm will produce a higher systolic reading if the wrong sized cuff is applied. There are two measurements in a blood pressure reading, the systolic and the diastolic....
user avatar
  • 6,524
8 votes
Accepted

How fast is blood replaced in the body?

Calculating from the numbers Wikipedia's articles on bone marrow and red blood cells, the bone marrow in an adult human produces between 200 billion and 500 billion red blood cells a day, taking ...
user avatar
  • 1,970
8 votes
Accepted

Is it possible to change person's blood group?

Yes, it is possible. In a bone marrow transplant, all of the patient's bone marrow is destroyed and replaced with donor marrow. Since red blood cells are created by bone marrow, the donor's blood type ...
user avatar
  • 9,313
8 votes
Accepted

Normal for menstruation blood to be brown/black at the start?

Menstrual blood is composed of a mixture of blood (blood cells), vaginal secretions, endometrial cells and inflammatory cells. I have found no study investigating the change in colour of mentruation ...
user avatar
7 votes

Does staying at high altitudes increase your stamina?

I could not find a report where this has been formally studied but it is highly likely that persons coming to plains after staying at high altitude will feel more energetic, for a few days at least. ...
user avatar
  • 1,760
7 votes
Accepted

What do these blood tests mean in general and why do doctors ask for them before taking action?

CRP C-reactive protein (CRP) is produced by the liver. The level of CRP rises when there is inflammation throughout the body. It is one of a group of proteins called "acute phase reactants" that go ...
user avatar
  • 6,480
7 votes
Accepted

How does a blood transfusion directly from one person to another through a line work?

Direct blood transfusion is both dangerous for the donor and inconvenient in a modern medical setting, so this does not really happen today outside of movies/TV. Before blood banking and ...
user avatar
  • 11.6k
6 votes
Accepted

Is it possible to get a cut from being elbowed in the head?

There are a few different types of injury to the skin. You can have a contusion (Bruise), abrasion (scrape), puncture, laceration or incision. The injury that you suffered is a laceration, as opposed ...
user avatar
  • 6,524
6 votes
Accepted

Are platelet donations needed more than whole blood?

I don't know if anyone can give a definite answer as to why these folks so badly wanted you to donate platelets over whole blood, but there are many possible reasons. Platelets give you more bang for ...
user avatar
  • 1,838
6 votes

Are there variations in blood cholesterol by age?

Levels generally increase until the ages of 50-60, then fall. In children, levels of LDL and HDL generally either rise or fall monotonically (i.e. continuously) over childhood; see Dai et al. (2009). ...
user avatar
  • 1,838
6 votes

dangers of keeping blood in a jar

First problem: Blood is an organic substance, and like all organic substances that aren't cooked, refrigerated or otherwise preserved, it will rot. You'll need to freeze or at least refrigerate it. ...
user avatar
  • 9,313
6 votes

Occasional medical tests and imageries

Screening tests such as "blood tests and imaging" have two costs and one benefit: the cost (dollars and possible health problems) of the actual screening, which can in some cases be free the cost (...
user avatar
  • 3,744
6 votes

Occasional medical tests and imageries

Great answer above. This is to add on to it: Making a decision on whether to recommend screening tests for the entire population is different from deciding whether to screen an individual patient. ...
user avatar
  • 5,693
6 votes
Accepted

What happens when a hemophiliac woman gets her period?

"Luckily" haemophilia only occurs in men*; women may be carrier of the disease but their bleeding tendency is in general less severe. However, haemophilia carriers and women with other bleeding ...
user avatar
  • 286
6 votes

How to calculate my "approximate" mortality rate while in ICU?

An individual person does not have a mortality rate: it means the fraction of people out of a group who die over a specific time period. It may seem like your particular chance of dying is that same ...
user avatar
  • 3,744
5 votes
Accepted

What are the hazards from smoking or drinking and then donating blood?

Smoking and drinking both put the recipient of the blood donation at risk or possible risk. Smoking causes nicotine to enter your bloodstream and usually breaks down into cotinine. Both of these are ...
user avatar
  • 4,896
5 votes

how many 'lives' are saved from one donation of blood?

I'm answering my own question, yay! This is my attempt to answer my question despite my lack of familiarity with much of the medicine. I therefore stress that I am not guaranteeing this answer, it's ...
user avatar
  • 985
5 votes

Can blood transfusion help in case of scleroderma?

I'm not aware of any work done in this area. A whole blood transfusion is not going replace circulating defective lymphocytes. On the other hand Hematopoietic Stem Cell Transplantation has some ...
user avatar
  • 13.2k
5 votes
Accepted

What causes aortic aneurysm

Aneurysm - a pathologic ballooning of a segment of a blood vessel Source: http://www.nhlbi.nih.gov/health/health-topics/topics/arm/types - Public Domain In order for an aneurysm to occur, conditions ...
user avatar
  • 701
5 votes
Accepted

What are the online blood testing services that allow to pick and choose exactly what test you want?

Somehow today I had a bit more luck in addressing my own question. It seems that many of the online blood testing services do offer tests on a disaggregated basis. Their more popular products are ...
user avatar
  • 749
5 votes
Accepted

Blood donor restrictions (Mad Cow Disease) in Australia/France for people who lived in Britain, is it justified?

Blood donor restrictiction aims at preventing the transmission of the variant Creutzfeldt-Jakob disease (also known as Mad Cow Disease for a layperson), which is a prion disease that leads to ...
user avatar

Only top scored, non community-wiki answers of a minimum length are eligible