Biology: research report – problem solving and communication Sarah Abdo 11.1

Question 2

Blood Products

Fresh Frozen Plasma: Plasma is the clear, pale-yellow liquid part of blood. It contains proteins (called clotting factors) that help make blood clot. This is important when the body is injured because clots are needed to help seal blood vessels and stop bleeding. Plasma also contains other proteins, such as antibodies, which help fight infection .One unit of FFP or thawed plasma is the plasma taken from a unit of whole blood. FFP is frozen within eight hours of collection. FFP contains all coagulation factors in normal concentrations. Plasma is free of red blood cells, leukocytes and platelets. One unit is approximately 250mL and must be ABO compatible.

FFP is usually given to patients who are bleeding because their blood is not clotting the way it should. Cancer patients would also be given fresh frozen plasma if they have a problem called DIC (disseminated intravascular coagulation). This is a rare condition where all of the clotting factors in the body are used up and/or broken down. Signs and symptoms (such as excessive bleeding and bruising) and blood tests help the doctor identify DIC. This is also in the case of trauma patients who have lost a massive amount of blood in a short period of type and not allowing the blood a chance to clot.

In serious bleeding due to excessive warfarin therapy (over-anticoagulation), rapid warfarin reversal is required. A number of options for warfarin reversal are available, including fresh frozen plasma. FFP provides an immediate replacement of vitamin K-dependent coagulation factors – but the correction of coagulopathy is partial. In fact Prothrombin complex concentrates are much more effective – completing the process within 10-15 minutes.

Haemophilia is a bleeding problem. People with haemophilia do not bleed any faster than normal, but they can bleed for a longer time. Their blood does not have enough clotting factor. Clotting factor is a protein in blood that controls bleeding. The condition is quite rare. About 1 in 10,000 people are born with it. However, the risk of transmission of infectious diseases is higher. Viral-inactivated FFP is available in some countries and is preferable. Circulatory overload is a potential problem with this treatment: since the concentration of each coagulation factor in FFP is low, a large volume of it must be given over several hours in order to achieve an adequate rise in factor level. This large amount of FFP needed can overload the circulatory system and stress the heart. Other complications of treatment with FFP can occur, particularly allergic reactions or lung problems. These problems are much less common if viral-inactivated pooled FFP is used. FFP is administered intravenously.

Red Blood Cells: Red blood cells (RBCs) give blood its colour. Their job is to carry oxygen from the lungs through the bloodstream to every part of the body. A substance in red blood

Biology: research report – problem solving and communication Sarah Abdo 11.1

cells called haemoglobin does this. Then, the red cells bring carbon dioxide (CO2) back to the lungs, where it’s removed from the body when we exhale.

People who have low numbers of red blood cells (RBCs) are said to have anaemia or they are anaemic. People who have anaemia may need RBC transfusions because they don’t have enough RBCs to carry oxygen to all of the cells in the body. Whether you need a transfusion for anaemia depends on many factors, such as how long it took for the anaemia to develop and how well your body is able to cope with it. Anaemia due to a sudden loss of blood will probably need to be corrected right away. Anaemia that develops slowly is less likely to cause problems, because the body has time to adjust to it to some extent. However, although blood transfusions can be life-saving, they are not without risks. Infections were once the main risk, but they have become extremely rare with careful testing and donor screening. Transfusion reactions and other non-infectious problems such as itching, shivering, headache, chest or back pain, throat tightness and nausea are now more common.

Transfusions may be given during or after surgery to make up for blood loss. The potential infectious risks of transfusion are well established. However, with modern screening techniques, these complications are of negligible significance to current practice. Less well recognized, and altogether more serious to the cardiac surgery population, is the impact of RBCs on lung function, circulatory status, and susceptibility to postoperative infection.

White Blood Cells: WBCs also called leukocytes, are essential for good health and protection against illness infection and disease; they are a very important fighting component of the blood. Although your white blood cells account for only about 1 percent of your blood, their impact is significant.

At one time, white blood cell transfusions were commonly given to cancer patients who could not make enough of these cells on their own or whose WBCs had been destroyed by disease or medicines. But for many reasons, such transfusions now are given rarely. For instance, it’s not clear how well the transfusions help reduce the risk of serious infections. And WBC transfusions can also cause a fever known as a febrile transfusion reaction. They can sometimes transmit infectious diseases, such as cytomegalovirus (CMV), which can be dangerous for people who have weak immune systems.

Many disadvantages present themselves as we find new ways to use the resources surrounding us. There are many groups with religious beliefs that are against blood donation overall such as the Jehovah's Witnesses who believe that the Bible prohibits ingesting blood and that Christians should therefore not accept blood transfusions or donate or store their own blood for transfusion. Additionally, on May 31st, 2002 the Long

Biology: research report – problem solving and communication Sarah Abdo 11.1

Island Blood Services lost 25% of the blood supply due to new FDA regulations concerning Mad Cow. Issues with disease and cross-contamination are a still very threatening prospect when donating or receiving blood, resulting in HIVs, AIDs and sometimes death. Also there are never enough people donating blood; only 4 people out of 100 who are able to donate blood actually do so. The average blood supply needs to be replenished constantly as blood products have a short shelf life, from 5 to 42 days.

Question 3

Perfluorocarbons

PFC are biologically inert materials that can dissolve about 50 times more oxygen than blood plasma. They are relatively inexpensive to produce and can be made devoid of any biological materials. This eliminates the real possibility of spreading an infectious disease via a blood transfusion. From a technological standpoint, they have two significant hurdles to overcome before they can be utilized as artificial blood. First, they are not soluble in water, which means to get them to work they must be combined with emulsifiers—fatty compounds called lipids that are able to suspend tiny particles of perfluorochemicals in the blood. Second, they have the ability to carry much less oxygen than haemoglobin-based products. This means that significantly more PFC must be used. One product of this type has been approved for use by the Federal Drug Administration (FDA), but it has not been commercially successful because the amount needed to provide a benefit is too high. Improved PFC emulsions are being developed but have yet to reach the market.

Question 4: Hormone Replacement Therapy

Aldosterone

Where is it made and released? Aldosterone is a steroid hormone. Its main role is to regulate salt and water in the body, thus having an effect on blood pressure. It is produced in the outer section (cortex) of the adrenal glands which sit above the kidneys. The hormone is absolutely crucial as Aldosterone acts on organs (the kidney and the colon) to increase the amount of salt (sodium) reabsorbed into the bloodstream and the amount of potassium removed in the urine. Aldosterone also causes water to be reabsorbed along with salt; which then increases blood volume and therefore blood pressure. Thus, aldosterone indirectly regulates blood levels of electrolytes (sodium, potassium and hydrogen) and helps to maintain the blood pH.

What causes lack of aldosterone being made or released? One of the diseases known to cause a lack of aldosterone to be made or released is a condition called Addison’s disease. Addison’s disease is a rare endocrine disorder. It occurs when the

Biology: research report – problem solving and communication Sarah Abdo 11.1

adrenal glands cannot produce sufficient hormones (corticosteroids– manmade drugs that closely resemble the hormone cortisol). It is thought to be caused by an autoimmune disorder. The cause for the disorder is not always known but it includes; damage to the adrenal glands that produce aldosterone, due to accident, surgery or disease (such as bacterial infections or cancer of the gland) and damage to the pituitary gland that controls the adrenal gland (for example, because of a tumour)

What is the genetically engineered hormone that is used? HRT is involved in restoring the balance of hormones to normal levels by giving the patients supplement hormones. Similarly, Addison's disease is managed with steroid (corticosteroid) replacement for life.

word count: 1489

REFERENCE LIST

Better Health Channel – Addison’s disease (last updated 10/31/2014)

You and Your Hormones – Aldosterone (written July 2012)

NCBI - Blood substitutes Artificial oxygen carriers: perfluorocarbon emulsions (published online Sep 24 1999)

Riess Jean G. Fluorocarbon-based oxygen-delivery: Basic principles and product development. In: Chang TMS, ed. Blood substitutes: Principles, methods, products and clinical trials. Karger Landes Systems, 1998:101-126

NCBI – Artificial Blood (2008 Jul-Sep)

Wikipedia – Jehovahs Witnesses and Blood transfusions (Nov 22 2014)

American Cancer Society – Blood Transfusion and Donation (Last Revised: 10/07/2013)

CSL Behring - Warfarin (Coumadin) Reversal 2014

World Federeation of Haemophilia – What is haemophilia? (Updated May 2012)

Australian Red Cross Blood Service – Why donate blood

HOFSTRA university – Blood Drive: Why we need more blood donors…