Finally, in March of the following year, parallel testing was completed. Because of time constraints, not all functions were tested, in particular, functions pertaining to the issue of products. Management was aware but decided to go ahead with implementation of the system.

In April, the new system at PEC was implemented with no major problems. Everything was okay until $3$ months later, when the distribution supervisor noticed that the system had allowed the release of human T$-$cell lymphotropic virus $($HTLV$)$ I$/$II repeatedly reactive donor units. The PEC QA department was immediately notified, and recall procedures were initiated. By that time, $35$ donor units and all their parts had been released.

What did PEC fail to do$?$ What were the consequences?

What are some of the factors that contributed to the release of unacceptable units?

What steps could have been taken to prevent this situation?

Exercise $1\mathrm{.}2$

AKC Blood Center collects more than $600$ platelet apheresis products each month. Platelet counts for donors and these products are determined using KB$1,$ a state$-$of$-$theart automated hematology instrument. This piece of equipment, similar to many others, requires extensive QC and preventive maintenance by the manufacturer. During the last $4$ days, Fred, the medical technologist assigned to run the instrument, has failed to notice that the low$-$level control has consistently fallen below the mean. Fred has been too busy trying to train new personnel in the department and has had no time to plot his results on the QC chart, which is a departmental procedure requirement. If he performed this task, he would have noticed the obvious shift.

Today the new trainee, Fran, is running platelet counts with Fred's assistance. Once again, the low$-$level control falls below the mean. On this run, the control falls outside the manufacturer's range altogether. Fran notices the value is flagged by KB$1$ and notifies Fred of the problem. Fred is too busy on the phone handling an irate call from a client hospital and tells Fran to "keep running it until it falls in$.$ You know, sometimes it takes a while for controls to come in$."$

If you were Fred's supervisor, what would you do$?$

What is the root cause of the problem?

What steps can be taken to prevent this situation?

What is your opinion of Fred's results since he started using the instrument?

Exercise $1\mathrm{.}3$

The transfusion services department at PSB Medical Center has always been happy with the level of service offered by YR Blood Center. However, during the last $3$ months, they have noticed quite a few platelet units with unacceptable visible clumping. If you worked for the QA unit at YR Blood Center and were asked to investigate this problem, what tigate to identify the root cause of the problem?