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Quick Summary
Eligibility
Just who can give blood? Well you must be at least 17 (16 with parents' permission), you must weigh 110 lbs or more, and you must be in good general health. You should not donate if you are pregnant. There are a number of medications which may make you ineligible (for anywhere from a few days to permanently), and there some diseases that will do the same. International travel may also make you ineligible for varying times. It is fairly complex, and the best way to find out if you are eligible is to simply make an appointment to donate and go in.
How Long?
A whole blood donation will take between 45 minutes to an hour. There is an interview that will take 10 - 15 minutes, about 5 minutes preparation time. Most donors will fill the bag in 10 - 15 minutes, and you'll spend about 10 - 15 minutes drinking some juices and eating free snacks. Plasma donations take between an hour and a half to possibly two hours, and platelet donations take a little bit longer.
How Often?
This depends on the type of donation. Your body will replace red blood cells lost when you donate whole blood in about 42 days, and you become eligible for another whole blood donation in 56 days (8 weeks). You can donate plasma every 30 days, and platelets every several days since your body replaces those in about 24 hours.
Does It Hurt?
Basically, no. It is no more uncomfortable than having a blood test done for your doctor, and for the vast majority of donors, there is no discomfort at all. Sometimes, I feel a tiny little poke when they insert the needle, but most of the time I don't feel anything at all. The most painful part of plasma and platelet donations for me (and most other donors) is getting on the scale (the computer that runs the machines that separate these products needs to know your weight). Because these donations take a little longer, I have a tendency to doze off while donating plasma and platelets.
Side Effects?
Essentially, none. You'll be asked not to engage in strenous work for 24 hours (if you're male, they'll write you a note to give to your wife regarding this if you ask), and the FAA requires 72 hours before piloting an aircraft. You'll need to drink more liquids and stay hydrated for the next day or so, but that's good for all of us anyway. Very occasionally, you might develop a small temporary bruise at the donation site on your arm, but it will go away in a day or so.
What Blood Type Is Most Needed?
Really, only one type is needed ... red. A former medical director for BloodSource would tell you, "The rarest blood type is the type that isn't available when the patient needs it." Type O positive is the most common while type AB negative is the least common. However, keep in mind that the need for various types follows the same pattern as the prevalence of blood types in the population -- that is, there are more O positive patients than AB negative patients, so, except for O negative, it really doesn't matter. O negative is explained a little further down.
How Long Does Blood Last?
Again, it depends. The clock starts when you fill the bag. After that, whole blood will last for 42 days. Plasma can be frozen and has a lifetime approaching a year. Platelets last for five days. Thus, blood and blood products are a perishable commodity, and managing the blood supply is a very complex task. That same former medical director often said, "The best place to store blood is in the donor," so having an adequate supply of repeat donors that can be called upon in times of need is critical.
Who Regulates the Blood Supply
Blood and blood products are defined as drugs by the FDA hence the FDA regulates the entire process from interviewing through the delivery to a hospital. The staff are licensed for their various jobs, training is continuous, and the FDA prescribes essentially every step in the process.
Can I Catch A Disease By Donating?
That would be a big NO! Everything that touches you or your blood during any donation is brand new, sterile and sealed until it is used, and nothing is ever reused. Even the little sponge used to sterilize your arm is tossed after use. Sometimes, the nurse may want to mark the location of your vein with a little purple felt pen. It too is sealed, it will be used once on you, and then tossed, or she'll give it to you if you ask.
Do I Really Save A Life With My Donation?
Yes, you really do, and it's not just one! Very few patients require all of the components in whole blood. The likelihood is very high that your donation will be disassembled in the laboratory into red blood cells, plasma, and platelets, each destined for a different patient with different needs. Back
The Process [Whole Blood]
What follows is the process for donating whole blood at BloodSource (the only place with which I'm recently familiar). Some details may vary between blood banks, but probably not very much since, to keep the blood supply safe, and protect donors, the process is highly regulated by the FDA.
Before Arrival At The Blood Center
For a day or so before your appointment, it's a good idea to hydrate well (that's actually a good idea all the time). Be sure to eat breakfast or lunch, depending on your appointment time. Just don't come in hungry.
Interview
Safety and health of our donors and safety of the National blood supply is paramount. Over the years, the blood banks and the FDA have developed a detailed understanding of those things that would create a risk to the donor or the blood supply. Consequently, you will complete an interview every time you donate. It's repetitive, and some wonder why "yet again," but the medical situation changes daily as new research surfaces, and it is really important, both for you and for the recipients of your donation.
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You will need a government issued photo ID (or if you are a regular donor, your donor card)
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If you are not yet 17, you will need a permission card (available at your blood center) signed by your parents.
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The interviewer will take your pulse and your temperature and print an interview form.
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You'll be asked to verify the information on the interview form (name, address, phone, etc.)
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The interviewer will poke the end of one of your fingers, squeeze out a little drop of blood, and use it to fill a couple of very small glass tubes, putting a little band aid on afterwards.
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She'll put a drop of your blood into a small vial filled with a blue solution. It's copper sulfate, and she's looking for the drop to sink (this means the ratio of your hemoglobin to the total volume of blood is high enough to donate).
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The "sink test" is really a screening. If the drop sinks, it assures that your hematocrit level is plenty high enough. If it doesn't sink, the interviewer will put the tubes in a small centrifuge, and then directly measure your hematocrit level. Often, a "floater" will measure out just fine. See below for more information.
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You will then answer a series of yes/no questions regarding drugs you take, travel, diseases you may have had in the past, a little family history, and the like. Your answers to these questions will further determine your eligibility and insure your safety as a donor and a safe blood supply. For example, if you have traveled to an area that the Centers for Disease Control (CDC) has designated as a malarial area (e.g. some parts of Mexico), you cannot donate whole blood or platelets for 1 year, although you can donate plasma.
Bleeding Into The Bag
The blood draw takes place with you reclining in a very comfortable chair. You can usually specify if you desire one arm or the other, but I'd recommend leaving that choice up to the nurses. The blood will be drawn from a vein in your forearm close to the inside of your elbow and most peoples' arms vary a bit between right and left, and it's best if the nurse chooses the best one. It really doesn't matter if you're right or left handed, there is no discomfort or impairment from donation. The nurse will take your blood pressure and write it on a receipt form that also has the catalog number of your blood bag on it (I keep these, and show them to my doctor each year when I go in for the annual physical giving her an ongoing record of my blood pressure). She will then clean and sterilize the area and allow it to dry.
When dry, the nurse will insert the needle, remove a clamp on the tubing, and the blood will flow into the bag. The bag is actually a collection of bags ... possibly 3 or 4, all connected by tubing and maybe with a small filter between two of them. Only the top bag will fill. All the others are used during processing in the laboratory. Every bag has the same "blood number" plus bar code that is on your donation receipt and the bag assembly rests on a scale on the floor. The top bag has a small amount of citrate solution in it and the nurse will shake the bag assembly periodically to keep the blood and citrate mixed. The citrate retards clotting of your blood in the bag during handling. All this time, you'll be gently squeezing a rubber ball or the like to keep the blood flowing into the bag.
Finishing The Donation
When the bag is full (based on weight), the nurse will clamp the tubing to stop the flow, and will fill several small test tubes through a fitting on the tubing near the needle. These test tubes are also coded with the blood number of your donation, and are used for testing your donation in the laboratory. At this point, the nurse will remove the needle from your arm, cover the insertion point with a piece of gauze, and have you put some pressure on it and hold your arm above your head. The tubing with the needle will be sealed, removed and discarded, and your bag assembly will be put in a box on ice (or in a fridge).
The nurse will then check to make sure the needle spot isn't leaking (almost never happens), and will put a stretchy wrap around your arm to hold the gauze pad in place. You'll get some instructions on how long to leave the wrap on (at least 4 hours), a caution not to engage in high-exertion activities for 24 hours, and not to pilot an aircraft for 72 hours. You'll remain in the chair for 2-3 minutes, and then head over to get some refreshments. Depending on how many donations you have made, you may get a T-shirt or other gift. The "Life Is Unpredictable" at the top of this page is actually a photo of the front of my favorite BloodSource T-shirt. All the men love it, the women are sort of so-so. Local merchants (e.g. Baskin Robins, or Round Table Pizza) often cooperate with BloodSource by offering a coupon to all donors good for a free item. If this is your first donation, you'll receive a donor card in the mail in a few weeks which will tell you your blood type if you don't already know. Back
Platelets and Plasma - Apheresis
What Are Platelets and Plasma?
Platelets are one component of your blood, and they play a big role in clotting when you are injured. Patients with hemophilia and other diseases that retard their blood's ability to clot often require transfusions of platelets to control and stop bleeding. When collected into a bag by themselves, they are a nearly white, thick liquid. The machines will collect a little of your plasma along with the platlets to keep them from sticking together (that is their job, after all). Of all the components in your blood, platelets are the shortest-lived, good for 5 days after donation. Conversely, your body makes new platelets continuously and very rapidly. It will replace all the platelets that you donate within 24 - 36 hours.
Plasma is the liquid portion of your blood that carries the red cells, white cells, platelets, and a host of other cellular products. By itself in a bag, it is a thin, yellow liquid. Mainly slightly salty water, plasma also carries a number of dissolved biological chemicals and factors, including antibodies (part of your immune system) and other components. Plasma can be frozen and stored for fairly long periods approaching a year or so.
What Is Apheresis?
Apheresis is the process whereby you donate one or more of the components of your blood. The components that are not being donated are returned to you. Since your body will replace platelets very quickly, you can donate them often. You can generally donate plasma once every 30 days (if you're willing to take a short physical and you meet a few other requirements, you can become a "frequent plasma donor" and donate every 72 hours), whereas red cells are replaced more slowly, and the time between donations for whole blood (or red cells) is 8 weeks.
Donating platelets and/or plasma is a lot like donating whole blood, except instead of bleeding directly into a blood bag, your blood is processed through a centrifuge in real-time, the component(s) being donated are collected in bags, and the remainder is returned back to your body. Although quite different technically, to us laypeople, the process and machinery is pretty much the same for either platelets or plasma.
The Machinery
The centrifuge machine is computer controlled. As with whole blood donations, all of the plumbing (plastic tubes) and other parts that come in contact with your blood are removable, come in sterile sealed packages, are used once for your donation, and then discarded. During the donation, a small bag of a citrate solution will be added as your blood is collected to retard clotting in the machine. At the end of the donation, another little bag of saline solution will be returned to you to replace some of the blood volume lost to the donation. Like everything else in the donation process, these bags are one-time-use and will be discarded.
The Process
Just as with whole blood, the process will begin with the same interview with the exception that the nurse won't bother with the "sink test" in the copper sulfate. The machines actually need to know your hematocrit level, so they'll take the two little capillary tubes to the centrifuge immediately. The machines also need to know your weight so you'll be weighed on the way to the chair (the most painful part of the process for most of us!).
The nurse will take your blood pressure in the normal manner, and then will put a similar inflatable cuff on your upper arm, this one controlled by the machine. The vein in your arm will be cleaned and sterilized just as with whole blood, you'll squeeze a rubber ball, and the nurse will insert the needle. Now, unlike whole blood where the test tubes are collected after your donation, she will collect 3 or 4 tubes first, and then connect the needle to the machine and turn it on. The cuff will inflate and gently squeeze your arm, and you'll be asked to slowly and gently squeeze and release a rubber ball (this helps keep the blood flowing into the machine which also has a pump).
Your blood flows into a centrifuge bowl (part of the sterile, one-time-use package), and the components are separated and collected. When the bowl is full, the cuff will deflate, you stop squeezing, and the contents of the bowl will be pumped back through the tubing and into your vein. When that has completed, you have finished one "pass." The cuff will reinflate, you begin squeezing again, and the bowl will refill with you blood for the second pass. If I am well hydrated (I have a kidney injury so I always stay well hydrated!), I'll fill the plasma bag in 3 passes, for a total time on the machine of around 45-50 minutes which seems to be about the same as most other donors. Platelets may take 4 or 5 passes since they make up a smaller part of your blood than plasma so each pass yields fewer of them and the time on the machine is somewhat longer (BloodSource provides you with a television and a selection of DVD's to pass the time).
When the last of your blood has been returned to you, the machine will return some saline solution to you as well. This "bulks up" your blood volume and keeps your body happy. Generally speaking, the solution is a little colder than your body, and you may notice the saline return. I tend to get a bit cold during a plasma or especially platelet donation, and they provide a blanket for me. The citrate anti-coagulant added to your blood as it fills the bowl will be metabolized by your body when it is returned to you. That process sometimes makes some donor's lips tingle very slightly, which can be relieved with a couple of antacid tablets (something about the calcium in the tablet speeding up the citrate metabolism). I've never noticed the tingling however.
The rest of the process is just like whole blood. The nurse will remove the needle and put the stretchy wrap on, you go get some snacks and especially some liquid like juice or a soda or just water (coffee does not count!). You should drink lots of liquid for the rest of the day (you should all the time), avoid high-exertion activities, and eat well. Again, don't pilot a plane for 72 hours. It's all very simple for us donors, the staff do all the work, they take really good care of us, and we get to be the life savers. Back
Blood Types
The "A - B - O" Game
A long time ago, it was discovered that all human blood is not identical. It turns out that there are two antagonistic factors, creatively called "A" and "B" and whether or not you have them is genetic. People with the A-factor only are Type A, those with the B-factor only are Type B, and those with both factors are Type AB. Those with neither A or B-factors are Type O.
These factors are not distributed equally across the population, they are heavily skewed towards Type O and A, as shown in the chart at the right. Nearly half (46%) of the overall population will have Type O blood, carrying neither the A or B factors. Type A is the next most prevalent at 40%, and those with Type B blood will make up about 10%. Only 4% of the population has Type AB blood.
Remember however that, while Type AB is the "rarest" type, it also represents the least number of patients requiring blood at any given time. As mentioned above, "The rarest blood type is the type that isn't available when the patient needs it."
Now, doctors always seek to provide a patient who needs it with blood of the same type. However, in a true emergency, there are some alternatives. Transfusing blood that contains a factor that the patient's blood does not contain can be fatal. Thus, giving Type B blood to a Type A or O patient is out of the question. However you can give Type B blood to a Type AB patient because she already has the B-factor in her blood. Thinking this over for a moment leads to the concept of "Universal Donor" and "Universal Recipient," and of course, Type O donors can donate to patients of any of the other three types because Type O blood does not contain either A or B factors. Likewise, a Type AB patient can accept blood from any of the other three types. Again, this is not standard practice by any means, and there are at least two other factors that affect this.
Rh Factor
In addition to the A and B factors, there is an additional factor that needs to be considered. Again, it's another of the "Either you have it or you don't" things. Those that have it are said to be "Rh Positive," and those that don't are "Rh Negative." Basically, it is important that the Rh Factor of the donor's blood match that of the patient, although again in a real emergency, Rh Negative blood can be given to an Rh positive patient, but not the other way around.
Most people are Rh Positive. It depends on your A-B-O blood type to a small extent, but for Types O, A, and B, approximately 85-90% will be Rh Positive. Upwards of 95% of Type AB people will be Rh Positive. Back
The Magic of Type O Negative
Cytomegalovirus
The mouthfull in the sub-title is usually abbreviated just CMV. Like Rh Factor, you either have it or you don't, and roughly half of the population has it. CMV is a ubiquitous (I love that word!) virus found in the environment. For healthy adults, and even for healthy older kids and teens, it is totally harmless, and you almost never know when and how you've acquired it if you have. Once you have it, you have it for life. The test for it is applied to every donation in the laboratory because, even if you are negative for many years, you can acquire it at some point. You can't even predict that you may or may not be CMV positive based on your activities, places you have been, and lifestyle. I spent over 3 1/2 years on the ground in the two Vietnams, Laos, and Thailand, got scads of repeated immunizations for tropical diseases, many of which I can't even pronounce, was injured a number of times - sometimes without immediate medical treatment - drank the water, ate the food, and even was in a survival mode for awhile, and I am CMV negative, or at least I still was last month when I last donated plasma. It's just totally unpredictable.
The problem with CMV positive blood occurs for patients with compromised immune systems, and that would include newborns and especially premature infants whose immune systems are still developing. Patients who have received transplants and whose immune systems have been purposely suppressed are another category. For these patients, it is critical that they receive CMV negative blood.
O Negative - CMV Negative Donors
We've already seen that a Type O person can donate to any blood type, however the Rh factor must match ... or be negative (i.e. the donor does not have the Rh factor). So, Type O Negative blood and blood products do have special uses that other blood types do not. If an O Negative donor also happens to be CMV Negative, that donor's blood is very special because it can be used to treat newborns, premature infants, and those with suppressed immune systems. Such donors are scarce. Only about 15% of all Type O donors will be Rh negative, and only about half of those will be CMV negative as well. Blood Centers often ask these donors to donate on an on-call basis when there is a specific need.
So, Go Save A Life!
Ask most people to list those who save lives, and you'll likely hear, "Doctors, Nurses, Firefighters, Paramedics, Police Officers, and the like." Nearly everyone will miss the single largest group -- Blood Donors!
If you've gotten this far, there are life-saving opportunities just waiting for you. In our area, we just had a 17-yr old from an auto accident that needed 76 units of red blood cells and I don't remember how many units of platelets and plasma -- well over 76 donors, and he is not an isolated case. You don't need any training, it doesn't hurt, it is safe, it doesn't take all that long, and you'll get some free food, drink, and sometimes clothes. Most of all, however, you'll have saved someone's life, and knowing that feels really really good!
Now, consider yourself flogged.
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When I retired in 2000, Andrea and I agreed that we'd each get out of the house one day a week so the other could have a day at home alone. She had been spending Tuesdays down at Auburn Needleworks, the local knitting and needle point shop with a group of other women who share her hobbies. That left me needing to find some weekly activity to occupy my time.
