Appropriateness of red blood cell transfusions in major urban hospitals and effectiveness of an intervention.

OBJECTIVES: To assess the appropriateness of red blood cell (RBC) transfusions and the effectiveness of an intervention to reduce inappropriate RBC transfusions. DESIGN: Medical record audit by hospital staff using a data form, before and after randomly allocated interventions (letter only or letter+visit). Criteria for assessing appropriateness of RBC transfusions were based on a systematic literature review. SETTING: Ten major urban hospitals in Sydney, New South Wales, in 1998 and 1999. SUBJECTS: Medical records of up to 120 patients at each hospital (n=1117). INTERVENTIONS: Letter-only (5 hospitals)--results of first audit at the hospital mailed to chief executive officer of that hospital; letter+visit (5 hospitals) results of first audit at the hospital presented by the research team to a meeting of that hospital's staff, and then mailed to the chief executive officer. MAIN OUTCOME MEASURE: Proportion of RBC transfusions assessed as inappropriate. RESULTS: At first audit, 35% of RBC transfusions were assessed as inappropriate. Small reductions in inappropriate transfusions were found at the second audit, but the change was significant only for the hospitals receiving the letter-only intervention. About 5% of patients received a single RBC unit; 40% of single-unit transfusions were inappropriate. More RBC transfusions were inappropriate in surgical patients than in those treated by other specialties. CONCLUSIONS: About a third of RBC transfusions were assessed as inappropriate. The interventions had only a small effect on transfusion appropriateness.

Infrastructure for monitoring blood transfusion practice in New South Wales hospitals.

OBJECTIVES: To determine the existing infrastructure for monitoring blood transfusion practices in New South Wales hospitals. DESIGN: A questionnaire survey conducted in August 1998. PARTICIPANTS: All healthcare facilities known to have used blood products from the Australian Red Cross Blood Service--New South Wales in the 12 months before the survey. MAIN OUTCOME MEASURES: Existence of a transfusion committee and policies and procedures to ensure appropriate use and issue of blood products; monitoring expiry rates of red blood cells, platelets and fresh frozen plasma; using a maximum blood ordering schedule (MBOS); and measuring the crossmatch to transfusion ratio (CT ratio). RESULTS: 224 hospitals were surveyed and 144 responses were received (64%). Twenty-five hospitals (17%) had a transfusion committee; 60 (42%) monitored expiry rates of red cells, and 39 (27%) and 42 (29%), respectively, monitored these rates for platelets and fresh frozen plasma. Thirty-three hospitals (23%) used an MBOS and 43 (30%) measured the CT ratio. However, over 70% of the larger hospitals (> 200 beds) had all these aspects of transfusion infrastructure in place, and 35% had transfusion committees. CONCLUSIONS: Our survey showed that, overall, there was a lack of transfusion infrastructure in NSW hospitals. However, most of the hospitals with more than 200 beds had infrastructure in place to monitor transfusion practices, but only a minority had established transfusion committees.

A novel approach to the assessment of variations in the human platelet count.

This is the first report of a method to assess the significance of numerical changes in the platelet count based upon a result exceeding the normal intra-individual variation in platelet numbers. Serial platelet counts from 3,789 subjects were analysed to determine the intra-individual variation in platelet numbers. A platelet count difference of 98 x 10(9)/L in males was found to represent a change that would occur by chance in less than 1 in 1,000 platelet count determinations. Tables to determine the significance of platelet number variations, given N previous observations, are provided at two probability levels. The repeatability of the platelet count was calculated as 0.871 (males) and 0.849 (females) indicating that the heritability of platelet count is high and that the platelet count is predominantly genetically determined. A seasonal variation in platelet count was found with a 'winter' versus 'summer' difference of 5.10 X 10(9)/L (males) and 5.82 x 10(9)/L (females).

Chronic lymphocytic leukaemia with upper airway obstruction.

We report a case of B-cell chronic lymphocytic leukemia in a 58 year old female in whom the clinical course was dominated by upper airway obstruction due to massive enlargement of the palatine and later the lingual tonsils. The peripheral blood morphology and immunophenotype were typical of chronic lymphocytic leukaemia with expression of CDl9+, CD20+, CD5+, CD23+ and HLA-DR+ together with weak, surface immunoglobulin with monoclonal lambda light chain. Therapy included surgical removal of the palatine tonsils and later chemotherapy, both of which provided temporary relief of obstruction before recurrence of obstruction at the site of the lingual tonsils. Lasting relief from mass effect and obstruction only occurred following localised radiotherapy to Waldeyer's ring.

Characterization of pyrimidine metabolism in the cellular slime mold, Dictyostelium discoideum.

The arginine-independent, de novo biosynthetic pathway of pyrimidines in Dictyostelium discoideum is initiated by a class II carbamoyl-phosphate synthetase (EC 6.3.5.5) specific for pyrimidine biosynthesis which utilized L-glutamine as its N donor and was partially inhibited by both UTP and CTP. The second step in the de novo pathway was provided by an unregulated aspartate transcarbamoylase (EC 2.1.3.2) which primarily appeared as a multimeric enzyme of 105 kilodaltons. The next enzyme, dihydroorotase (EC 3.5.2.3), was approximately 90-100 kilodaltons. Although the early enzymatic activities of the pyrimidine pathway appeared to reside in independent protein complexes, various unstable molecular species were observed. These structural variants may represent proteolytic fragments of a multienzyme complex. In addition to de novo synthesis, the amoeba demonstrated the capacity for salvage utilization of uracil, uridine, and cytidine. Upon starvation on a solid substratum, axenically grown amoebas began a concerted developmental program accompanied by a restructuring of nucleotide metabolism. The absolute levels of the ribonucleotide pools droppedby 98% within 30 h; however, both the adenylate energy charge and the GTP/ATP ratios were maintained for 50 h after the initiation of development. The maintenance of these metabolic energy parameters required the tight cell-cell contact necessary for development, and the capacity for pyrimidine metabolism was maintained throughout developmental morphogenesis.