The comprehensive blood bank survey program of the College of American Pathologists, 1974.

Results of the 1974 College of American Pathologists Comprehensive Blood Bank Survey Program show that ABO and Rh typing are still holding their percentage of excellent (99.48%) accuracy. At least some of the errors still occurring are due to clerical mistakes in filling out the forms and not to technical inaccuracy.

Identification of human hemoglobins by use of isoelectric focusing in gel.

Newly-developed gel isoelectric focusing techniques provide for rapid and correct identification of human hemoblobins. With this technique, we examined samples previously identified by the National Hemoglobinopathy Standardization Laboratory of the Center for Disease Control. A wide variety of both normal and abnormal hemoglobins was included in the 134 different specimens examined.

Pre-instrumental variables in coagulation testing.

A number of variables thought to affect measurement of prothrombin time (PT) and partial thromboplastin time (PTT) were examined in an effort to determine more precisely their effects on these measurements. On the basis of these studies, it is proposed that blood specimens be anticoagulated with one part 3.8% (w.

Studies of fibrinogen measurement in the CAP survey program.

A review of the College of American Pathologists' Surveys experience in fibrinogen testing from 1967 to 1974 is reported. Trends in fibrinogen methodology and the emergence of a consensus choice of the modified thrombin time method are documented. The reasons for these changes from former methods are discussed.

The partial thromboplastin time in the CAP survey program.

Analysis of the data for the 1969 to 1973 CAP Surveys of proficiency in partial thromboplastin time (PTT) determination indicates more than desirable variability in this measurement. Non-activated procedures show greater interlaboratory variability than activated methods; therefore, they may be preferable for routine use. It is likely that many laboratories have not determined their own upper limit of normal for their PTT system and thus have received unacceptable evaluations in the Surveys.

The College of American Pathologists comprehensive blood bank survey program, 1973.

The 1973 Comprehensive Blood Bank Survey Program of the College of American Pathologists was administered to 2,200 laboratories and blood banks throughout the United States. The results showed a considerable increase in the accuracy of the testing and in the performance of reagents. Accuracy of ABO testing was 99.

Use of platelet aggregometry in selection of compatible platelet donors.

To determine if platelet aggregometry was useful in selecting compatible platelet donors, six patients who had become refractory to random platelets were studied. Serum from the patient was added to citrated platelet-rich plasma from the prospective donor in a standard aggregometry system. Serial aggregometry studies revealed no platelet aggregation unless the refractory state had been reached.