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Blood Bank Guy Podcasts and Podlets are educational videos covering transfusion-related topics.
Available Now:
   What the H? (Bombay) Podcast
   Acquired B Podlet


Download Dr. Chaffin's 2014 blood bank review notes. Check out the topic discussions on the Acquired B Phenotype, massive transfusion, polyagglutination, and anti-G.

A glossary of Transfusion Medicine Terms is available for your reference.


Ask The Experts your questions about blood group antigens, antibodies, and problems.


Test your knowledge in the BBGuy quiz section.


Common questions received from site visitors and attendees at review courses.

Osler Course

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Joe Chaffin, MD

I started in 1998 as a way to help more people learn basic transfusion medicine.

Blood Bank Guy

I am a board-certified pathologist and blood banking and transfusion medicine specialist. I spend my days working as Chief Medical Officer for LifeStream, a blood center in Southern California that is an affiliate of Blood Systems. In the past, I have been a Clinical Pathology Director (Cedars-Sinai Medical Center, Los Angeles), a medical director at another blood center (Bonfils Blood Center, Denver, CO), a hospital-based anatomic and clinical pathologist in multiple hospitals in Northern Colorado, and an Army pathologist (Walter Reed Army Medical Center, Washington, DC). I've also been blessed to be the main blood bank lecturer for the Osler Institute's Pathology Review Course for the last 19 years.

Teaching is my passion, and this web site allows me to do that with a really wide audience. I love teaching people the "nuts and bolts" of blood banking, and I try to do that with illustrations, humor, occasional irreverence, and an intention to communicate things in a way that helps you understand and retain as many facts as possible. My Mission Statement for the Blood Bank Guy website: Teach basic transfusion medicine to as many as possible.

Is this site for me?

I designed and continue to develop for anyone with an interest in the basics of Blood Banking/Transfusion Medicine. People that have told me that they find the site useful include pathology residents, transfusion medicine and hematology fellows, practicing pathologists, laboratory professionals and students (MT/CLS, MLT, and SBB), clinical physicians, and nurses across many specialties. Please understand that if you are looking for the most incredibly indepth look at every single topic in blood banking, you are probably not going to find all of that here, because my aim is to cover the basics as best I can! See my mission and vision statements for more.

"Blood Bank Guy?" Seriously?

I know; the name is stupid! The origin of the idiocy was back in the early days of my involvement with the Osler Institute in the mid-1990's, when people had no idea who I was before I would give the blood bank lecture (not that they should have; I wasn't then and am not now remotely famous), and I would hear them say things like, "what time does the blood bank guy start lecturing?", or, "who is the blood bank guy again?" (mostly true story: Many years ago, while riding in a hotel elevator at the Osler course, I heard one course attendee who did not realize I was riding with her ask a fellow attendee, "Why the &*%$ are we going down to listen to the *%$#*! blood bank guy?" I laughed for about a week about that one!). In addition, no one can ever remember how to pronounce my last name (it rhymes with "laughin'" and it doesn't sound like what happens when your skin rubs together too much!), so some people just say "the blood bank guy" because it's easier. I suppose I could just call myself "a" blood bank guy, because it sounds pretty lame to declare myself "the" as in "the one and only" blood bank guy, but that sounds even more stupid, doesn't it? So, the name is what it is, and I probably won't change it any time soon!