We do everything we can to minimize blood loss during surgery. Your blood pressure is lowered during the operation to cut down on bleeding, and cut blood vessels are zealously cauterized, and we use the smallest incision possible. Even so, almost all knee replacement patients need to be transfused after the operation because of oozing from cut surfaces, much of it occurring after the operation is over.
- Autologous Blood is blood donated by you and later given back to you. It is stored in a liquid state and is good for 42 days from the day of collection. It can be stored frozen for up to a year, but freezing triples the cost and is therefore only used in very special circumstances.
More can be taken over a longer period, but some of the units may have to be frozen if storage is required for more than 42 days. Note that blood already being stored in liquid form cannot be frozen if your surgery is postponed for any reason. Freezing must be done at the time of collection. If you have already given your blood for storage, and your surgery is to be delayed for any reason, we can use the “piggy-back” technique to save a unit of your banked blood that is about to expire. We give it back to you as a transfusion, wait ten minutes, and then take a fresh unit that will be good for another 42 days!
There is no age requirement for storing your own blood, and no specific weight requirement. However, if you are anemic (Hemoglobin under 11 gm/dl), we cannot take your blood. There are also some medical conditions which might preclude you from donating your own blood, such as some heart disorders.
- Directed donor blood is blood donated by a relative or friend. It is carefully labeled and reserved specifically for you. It is rigorously tested for disease, but it is still possible to contract disease through directed blood: the donor may not know he has the disease, and tests may fail to detect it. Directed donor blood is only given to you after surgery if it is medically necessary to do so. If you plan to have directed donors, it is best that you first donate a unit (450 cc) of your blood. Then, when your blood group is known, and the bank has a specimen of your blood to use in cross-match tests, suitable donors can be canvassed. Bear in mind that it takes a minimum of 48 hours to process and test blood before it can be transfused.
Once you know your own blood group the following table will help you to determine who might be a compatible donor:
Your Blood Group You Can Receive Blood From Donors With A+ A+,A-,O+,or O- A- A- or O- B+ B+,B-,O+,or O- B- B- or O- AB+ A+,A-,B+,B-,AB+,AB-,O+,O- AB- A-,B-,or O- O+ O+ or O- O- O-
Tell the prospective donor to go to the same blood bank where you gave your first unit, and to inform the bank that they want to give a directed unit of blood for you. You do not need to be present.
- Volunteer donor blood is blood donated by a member of the general public unknown to you. Potential donors fill out an extensive health questionnaire and the blood is rigorously tested. There are risks associated with receiving volunteer blood. Sometimes, in emergency situations, we may have to use volunteer blood if the amount of blood pre-stored for you is insufficient. But we would only do so in a rare, life-saving situation. Volunteer blood is rigorously tested and is safer now than it has ever been in the past.
replace the blood lost by your donations. Take these from the day
of your first donation until the day prior to surgery:
1.Iron (Nu-Iron), 1 tablet 2 times a day.
2. Folic acid, 1mg once a day.
3. Virtamin C, 250mg twice a day.
Disease Transmission Through Blood Transfusion
All blood intended for transfusion is screened for AIDS, but the tests are not sensitive enough. There is a gap (“window”), believed to be between six and 12 months, during which infected persons will test negative. This is the great danger of accepting blood from others. This problem will persist until a test is available which will show positive as soon as an AIDS victim has the virus in his blood. Other diseases can be transmitted through blood; for example, hepatitis. Fortunately the tests for them are more accurate. The chances of getting AIDS through volunteer blood is currently about 1:2,000,000.