According to current AABB Standards, a Platelets Pheresis unit can be stored at 20-24C with continuous gentle agitation for 24 hours to 5 days depending on the collection system used. However, if the Platelets Pheresis container has been opened (spiked), the product expires in four hours. In addition, the maximum time allowable for a Platelets Pheresis product to go without agitation is 24 hours. An e-network member wants to know what would be an allowable transfusion service policy for handling a Platelets Pheresis unit that was dispensed for transfusion, but which later was returned to the laboratory without being spiked (i.e., the product was never opened). Can the returned unit be dispensed for another patient within the product's original expiration date? What is the maximum allowable time that a Platelets Pheresis unit can be out of a transfusion service's control, before such a unit can no longer be re-dispensed, in the event it is returned unopened? Finally, how should a hospital monitor the temperature of a Platelets Pheresis unit once it has been dispensed?

Before broadcasting these questions network-wide, the opinions of some 'experts' in blood banking were solicited. Here is a summary what two experts had to say:

Expert #1 indicated that he was unaware of data that directly addressed the specific questions being asked by the inquiring e-network member. However, he was aware that whole blood derived platelets and Platelets Pheresis units could be stored/held for at least 24 hours without agitation within a temperature range of 20-24C. Therefore, in his opinion, a Platelets Pheresis unit could be dispensed, not be used, be returned unopened, and then be placed back into inventory (on an agitator) providing that the product was out of the blood bank for no more than a few hours, and providing that a 20-24C environment was strictly maintained. However, since this expert was unaware of data indicating a Platelets Pheresis unit was safe and efficacious enough to place back into inventory after exposure to temperatures ABOVE 24C, and since it is likely that a dispensed Platelets Pheresis unit could be exposed to temperatures above 24C, this expert deferred giving a recommendation for the length of time a Platelets Pheresis unit could be out of the blood bank, yet be OK to put back into inventory, if it is returned to the laboratory. What concerns this expert is that that increased temperatures above 24C increase platelet metabolism, and eventually lead to falling pH levels during the storage/holding period.There is also the issue of enhanced bacterial growth at higher temperatures, if bacteria are present within a Platelets Pheresis unit. This expert also commented that there are temperature indicator tags that might be useful. However, he was not certain if tags covering an appropriate temperature range were commercially available. To this expert's knowledge, such indicator tags were not used in current practice. The expert finished by commenting that it will be interesting to read how transfusion services currently handle this issue and he looks forward to the e-network discussion.

Expert #2 suggested the use of insulated containers, if maintaining strict temperature control of dispensed platelets is a concern. If used, insulated containers should be validated for their temperatureholding characteristics. The expert also pointed out that it would be prudent to keep the maximum time that platelets are out of a blood bank's control to a minimum, but certainly not to exceed the time that an insulated container, unopened, will hold the specified temperature.

What follows are comments that were submitted by the general e-network membership in response to the expert opinion as well as to the original questions:

ADDENDA June 13, 2001

1. A member of the AABB Standards Committee commented that the question posed was really three questions:

• What issues are posed by temporary discontinuation of agitation?
• To what temperatures can platelets be exposed without causing damage?
• What assurances are needed for a transfusion service to be able to reissue a Platelets Pheresis unit? 

What issues are posed by temporary discontinuation of agitation? According to the Standards Committee member, the recent publication "The effect of interruption of agitation on platelet quality during storage for transfusion" Hunter, Nixon and Scott Murphy in Transfusion 2001:41:809 confirms earlier findings of Moroff in Transfusion 1990:30:427) that discontinuation of agitation for periods of 24 hours or less has no demonstrable adverse effect on the platelets. Hence, the data supporting the AABB Standard that platelets may be subjected to a period of up to 24 hours of discontinuation of agitation...

To what temperatures can platelets be exposed without causing damage? According to the Standards Committee member, the S. Holme paper "Studies on platelets exposed to or stored at temperatures below 20C or above 24C" in Transfusion 1997:37:5-11,  documents that adverse affects of storage above and below the recommended "room" temperature storage are a function of both absolute temperature of exposure and the time period to which they were exposed. However, there were NO statistically significant adverse effects for up to 5 days storage between 18 and 26C! Hence, the FDA and AABB limits are admittedly somewhat more conservative than absolutely required.

What assurances are needed for a transfusion service to be able to reissue a Platelets Pheresis unit? According to the Standards Committee member the AABB standard for reissue 5.17.3 is delightfully vague about the temperature requirements for reissue of platelets (as opposed to red cells where the upper limit of warming is 10C). Specifically point 4 states: The records indicate that the blood has been inspected and that it is acceptable for reissue.

In short, according to the Standards Committee member, if it is reasonably conceivable that the issued component sat on the front window of an ambulance that sat in the hot sun awaiting the arrival of the patient being rescued from a fall into the Grand Canyon...well...that component should NOT be reissued (and probably not transfused, too!). Conversely, if it can be validated that the component stayed within the 18-26C range and was returned to agitation within 24 hours, that should comply with Standards

2. A community blood center physician reported that his facility ships to and receives back from regional hospitals Platelets Pheresis units. The blood center has established a policy that the regional hospitals must have platelet shakers and SOPs for the storage of the Platelets. The blood center ships Platelets to the regional hospitals in insulated boxes made especially for Platelet shipping. These boxes are QC'd each quarter with "live" products to verify that they can hold a temperature between 20-24C. The QC testing results have always been acceptable and the boxes can maintain and hold temperatures for 24 hours in most conditions. In addition, the blood center places Sebra chemical coolants inside the shipping boxes to help maintain a temperature between 20-24C. These Platelets are rarely off the shaker for more than 4 hours during shipment between the blood center and a regional hospital. Regional hospitals are required to have their own shipping SOPs when they return Platelets back to the blood center. They must use boxes that are provided by the blood center, and they should use the chemical coolants that the blood center provides to them. If Platelets are returned but not packaged correctly, the blood center personnel automatically take a temperature reading to verify that the Platelets are within 20-24C. In the last 5 years the blood center physician can remember only one or two situations where returned Platelets had to be discarded because they were improperly packaged. In the unusual circumstance that a Platelets Pheresis is off the shaker for more than 4 hours while being returned to the blood center, the physician states that his blood center would use 24 hours as the maximum allowable time off the shaker. Platelets out of a controlled environment and left off a shaker longer than 24 hours would be discarded.

ADDENDA June 29, 2001

3. The information provided by the network forum was greatly appreciated by our Transfusion Medicine Service.  This helped reassure us that our SOPs are appropriate and consistent with outside services.  This also provided additional insight as to protocols for re-issuing unused platelet pheresis which are returned to the Blood Bank. Thank you.

ADDENDA Aug. 30, 2001

4. A blood banker in New York has suggested that the decision to re-issue platelets that have been returned to the blood bank might include a grading system for platelet swirling. A standard for a minimum amount of observable swirling could be set below which platelets would not be re-issued. In the responding member's opinion, such a system can be set up based upon the following references:

• Bertolini F et al. Transfusion 40:121-122(2000) (Letter to Editor)
• Fijnheer R et al. Transfusion 30:20-25(1990)
• George V et al. Transfusion 29:273-275(1989). Also, a related article in J Lab Clin Med 103:620-631(1984).

ADDENDA Oct. 7, 2003

5. Editor's Note: Colleagues are referred to an ongoing discussion of this problem in the Aug. 2003 issue entitled 'How well do you know your Emergency Power System?

ADDENDA Dec. 14, 2005

6. A hospital transfusion service supervisor in Nevada reports that his hospital does not use temperature controlled transport containers when issuing blood components for transfusion and enforces a policy of discarding an RBC unit that is returned to the blood bank more than 30 minutes after it was dispensed. On the other hand, their local policy requires that they discard an FFP or platelet unit if it is returned more than 2 hours after being issued from the blood bank. They want to re-evaluate their policy of discarding non-RBC components such as FFP, thawed plasma, and platelets that are returned to the blood bank. They wonder what other institutions do about such returned components.

Please submit comments to the e-Network Forum.

Ira A. Shulman, MD
CBBS e-Network Forum Editor & Moderator