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The Benefits of Blood Donation with Dr. Elizabeth Stone

A doctor of transfusion medicine describes the importance of blood donation, the process behind donating, and what happens to that blood between the donation center and the transfusion for the patient who needs it.

For National Blood Donor Month, Courtney Allison speaks with Dr. Elizabeth Stone, an expert in transfusion medicine at NewYork-Presbyterian and Columbia. Unprecedented blood shortages mean that the need for donated blood is as critical as ever. Dr. Stone demystifies the process of giving blood, explains blood types, and shares how both the recipient and the donor can benefit from a single donation.

Episode Transcript

Welcome to Health Matters, your weekly dose of the latest in health and wellness from NewYork-Presbyterian. I’m Courtney Allison.

January is National Blood Donor Month, a time to recognize the importance of blood donation. As we’ve experienced unprecedented blood shortages in recent years, the need for blood is as critical as ever. 

So we talked to Dr. Elizabeth Stone, Assistant Director of Transfusion Medicine at NewYork-Presbyterian and Columbia. Dr. Stone demystifies the process of giving blood, explains blood types, and shares how both the recipient and the donor can benefit from a single donation.

Courtney: Hi, Dr. Stone. Thank you so much for being with us here today.

Dr. Stone: Hi, thanks so much for having me. It’s really my pleasure.

Courtney: So we’re here to talk about blood donation and January is National Blood Donor Month. Why is donating blood so important?

Dr. Stone: Blood donation is extraordinarily important. There’s no substitute for blood. Although many wonderful labs have tried very hard to create blood, we’re just not there yet. And so there are lots of different patient populations who need a lot of blood and who need blood sometimes emergently. So you have cancer patients, you have trauma victims, you have burn patients, and a lot of other patients who are getting routine surgeries also might need blood. And so if we don’t have a constant supply of blood from healthy altruistic donors, unfortunately, our patients will be in trouble. That’s one of the reasons why I’m very passionate about blood. Every time you donate blood, you can save up to three lives with each donation.

Courtney: I mean, that’s incredible. Three lives.

Dr. Stone: Yes!

Courtney: Okay, let’s start with a step by step of the process for donating blood. If someone comes in to donate blood, what’s going to happen?

Dr. Stone: Sure. So you walk in, you’ll register. Um, if you’ve donated before, you’ll have a blood donor card. And so then you can usually scan that card in. Otherwise you’ll register yourself. And there’s a very long questionnaire to make sure that you are safe to donate blood. And also that your blood is most likely safe to give to other people. It gets at your age, it gets at your medical history, it asks if you have cancer, it asks if you’ve traveled. And then it will get at other health questions. Like, do you take blood thinners? Have you ever had a blood transfusion yourself, or have you had a blood transfusion in the last three months? Um, but they’ll also ask, ask questions about various risk factors. And the questions can feel a little bit shocking for at least some of the questions. So for instance, there are a lot of questions about sexual history. There are questions about whether or not a potential donor has been recently incarcerated, whether or not IV drug use, and so it, it, it gets at risk factors and those risk factors are for HIV, hepatitis B and hepatitis C for the most part.

Once the questionnaire is done, then you’ll get your mini physical. They’ll check your blood pressure, check your weight, they’ll ask for your height, they will get your heart rate, and then they’ll do a little finger stick to get a drop of blood to measure your hemoglobin to see if you’re anemic. And so if you’re not anemic, then you will then wait and then go and donate blood. And so when you go to sit down to donate blood, they have these big comfy chairs where you put your feet up. And so then, they will collect some blood in a little pouch that’s attached to the donation bag. It takes anywhere from 5 minutes to 30 minutes. Um, your blood will go into the blood bag and when it’s full enough, they will take the needle out. You’ll sit there for a little bit. They’ll wrap your arm quite well to minimize any bruising from the, the, blood donation.

And then you get to have as much juice, cookies, potato chips, pretzels, whatever you want, or whatever they have available. So you’ll sit there, you’ll eat your snacks. You’re feeling good, you can go right on home, and you keep that pressure bandage that they put on for at least four hours and minimize physical activity for the rest of the day.

Courtney: How much blood do you give in a donation?

Dr. Stone: So you give about a pint of blood, it’s 500 mils. You have over four liters of blood, sometimes five liters of blood, depending on your size in your body. And so taking half a, half a liter out, it’s no problem.

Courtney: How often can you donate? Are there any guidelines to this?

Dr. Stone: So you can donate a unit of whole blood every eight weeks, or you can donate platelets every seven days up to 24 times a year.

Courtney: Every eight weeks, so that’s pretty often. I guess I thought you might have to replenish more. That’s really interesting.

Dr. Stone: No, that’s it. That’s it. A single red cell in your body lives for approximately 120 days. So we’re constantly making new red cells all the time.

Courtney: Well, what is a platelet, and… why is it that you can give platelets more often?

Dr. Stone: In your blood, you have red blood cells. They carry oxygen throughout the body. You have white blood cells, which are important for fighting infection. And you have these special cells called platelets, which are these very small cell fragments that are very important for clotting. With a platelet donation, they’re not actually collecting the whole blood. They instead put a patient on, it’s called an apheresis machine, and so they will have an apheresis procedure where, just like with whole blood, they will put a needle into your vein. Blood goes into the apheresis instrument. The blood gets spun in a big centrifuge and it gets separated into the blood’s components. The red blood cells, the white blood cells, and the plasma, which is a protein rich fluid that your cells will flow through in your body. All of that gets returned to the donor. The platelets, though, get collected in a bag and so you can then just collect the platelets. It’s a pretty amazing procedure. So there’s a lot of stuff going on in blood, you know. Unless you think about blood, blood seems like a pretty simple fluid. It’s not. It’s quite complicated.

Courtney: So how should someone prepare to give blood? You know, I think some people might just go in, “okay, I’m going to get blood today,” but are there things we could do to prepare ourselves for the procedure?

Dr. Stone: Definitely, um, it’s best to plan a week in advance, I would say. So, think about “I’m going to donate blood next week.” During that week, um, do your normal activities, obviously, but especially coming up the day before your blood donation, make sure you’re well hydrated and make sure that you eat balanced meals, especially before you go to donate blood.

Courtney: So this is really good to know. So well hydrated, meaning, so maybe like a little extra water throughout the week, being extra mindful of it.

Dr. Stone: Definitely. And I would highly recommend not having a lot of alcohol to drink right before you go to donate blood or even the night before. And if you want to exercise, you can exercise before you go to donate blood, but just make sure that you are very, very well hydrated that day.

Courtney: Is there anyone who should not give blood?

Dr. Stone: Yes, there are a lot of different populations who should not give blood. Um, if you are sick with any kind of infectious disease, you should not give blood. If you have cancer, you should not give blood. If you’ve traveled to an area that’s known to have malaria, you should not give blood. And also if, if you are anemic, you should not give blood. They won’t let you give blood. Um, additionally, if you have certain chronic infections like HIV, Hepatitis B, Hepatitis C, you shouldn’t give blood. If you’re pregnant, you also shouldn’t give blood. So there are a lot of different categories of, of people who should not be donating.

Courtney: Thinking of listeners who might be nervous to give blood or maybe someone is afraid of needles and that kind of stops them from going to do it. Do you have any tips for people who might be hesitant or nervous?

Dr. Stone: I do. First of all, if you come a little bit prepared, if you are well hydrated, that’s definitely a great step. If you do have a fear of needles, it’s best not to watch the donor specialist when they are first accessing your vein. Um, you can look away, but some great things that you can do is if you have your cell phone with you, make sure you have headphones, you can listen to calming music, you can watch a video, make sure you’re turned away. And so those, those kinds of things can help you donors who are more nervous about the actual needles or nervous about the donation.

Courtney: So, let’s follow the trail of blood for a little bit. What happens to the blood after it’s collected? Where does it go? How is it stored? And who decides where to send it?

Dr. Stone: So it depends on the blood product for storage. The whole blood for instance, will go to our collection center, um, where they will put that bag of blood in a special centrifuge and they’ll do something similar to that apheresis procedure. They’ll spin the blood in the centrifuge. They remove that unit of blood. The red cells are at the bottom, there’s a layer of white blood cells, and then on top of that you have platelets and plasma. They’ll express out the plasma, add an anticoagulant to the red cells, and then you have your packed red blood cell unit. Now a packed red blood cell unit can be stored up to 42 days depending on the anticoagulant and preservative solution that it’s in.

Courtney: We hear a lot about blood types. Talk about the different types and what it means to be a “universal donor.”

Dr. Stone:  So a universal blood donor is type O negative. And so that means any other type of blood can receive an O negative blood donation more safely than, for instance, someone who is type O who receives a unit of type A blood. And so that has to do with the glycoproteins on the surface of the red blood cells. Um, and so you can have the A glycoprotein, you can have the B glycoprotein, you can have both of them, or you can have neither. And by the time we’re about four to six months of age, you naturally make antibodies to the other types. So, somebody who’s AB can absolutely get O, A, or B, or AB. But somebody who is O can only get type O blood, and that’s because those antibodies are pretty strong against those red blood cells that get transfused. So if you are a type O negative, we would love your blood donations. But even if you’re type AB, we actually would love your plasma. So if you were to donate a unit of platelets or to donate even plasma, anybody could get that AB plasma or platelets. And so no matter what your blood type, we can use it.

Courtney: Well, and I think I’ve heard too, there’s actually health benefits to giving blood. So can you go into that a little bit?

Dr. Stone: That’s right. There are some health benefits to giving blood. Every time you go and donate blood you get almost like a tiny physical. They will check whether or not you’re anemic. So it’s, it’s pretty great. And you get to save lives too. So we’re, we’re pretty happy about that.

Courtney: That’s amazing. I mean, you’ve sold me. I’m to go make a, make a donation and schedule it. Thank you so much for being with us today and sharing all this amazing knowledge about blood.

Dr. Stone: Thank you so much for having me. It’s an important topic.

Our many thanks to Dr. Elizabeth Stone. I’m Courtney Allison.

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