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P D Mintz

Publications and source records attributed to P D Mintz.

At least 19 recordsLinked to original sources

Undertransfusion.

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Attitude

Detection of anti-A in neonatal serum.

The thirteenth edition of the standards of the American Association of Blood Banks did not require the use of A1 red cells (RBCs) or an indirect antiglobulin test (IAT) to detect anti-A in neonatal serum, whereas the fourteenth edition mandates both. The present study was conducted to help document the need for these changes. Incomplete expression of the A antigen in neonatal patients can contribute to the accumulation of unabsorbed maternal anti-A that is capable of mediating the immune destruction of transfused adult RBCs. Sera from 50 group A neonatal infants of group O mothers were tested for anti-A by using RBC segments of A1 and A2 units of AS-1 RBCs less than 14 days old and also with A1 reagent RBCs. Of 22 sera in which anti-A was detected by RBCs from the A1 units with an IAT, anti-A was detected by RBCs from the A2 unit in only 1 and by the reagent RBCs in 17. In 19 (86%) of the 22 neonatal patients in whose sera anti-A was detected, the antibody was found only with the use of anti-human globulin in the IAT. It is concluded that testing to detect circulating anti-A in neonatal patients should include an IAT, and that it is preferable to use A1 RBCs for the initial evaluation.

ABO Blood-Group System

Red cell survival studies in a patient with anti-Tca.

A radiolabeled, allogenic red cell survival study was performed on a patient who lacked the Cromer-related antigen Tca and who had developed the corresponding antibody. Red cell survival was 92% at 1 hour and 88% at 24 hours. Monocyte monolayer assays (MMA) and IgG subclass determinations were performed on samples from: (1) 1965, the period of initial antibody formation; (2) approximately two years before the red cell survival study; and (3) four months after the study. All samples reacted w+ to 1+ by the antiglobulin test. The earliest sample contained IgG1, IgG2, and IgG4 anti-Tca. Because there were 20.5% reactive monocytes in the MMA (normal range 0-3%), this antibody may have produced extravascular red cell destruction. In contrast to the initial example, the samples before and after the red cell survival study both contained IgG2 and IgG4 subclasses with 1.3% and 2.2% MMA reactivity, respectively. The current pattern of antibody subclass, the lack of reactivity in the MMA, and a red cell survival of 88% at 24 hours indicate that short-term transfusion support would have been well tolerated. This contrasts to the in vitro results obtained with the earliest sample, which suggest a clinically significant antibody. This appears to be the first report of a red cell alloantibody that remained serologically reactive but underwent a loss of its IgG1 fraction, which appeared capable of red cell destruction based on the MMA results.

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Type and screen.

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Blood Grouping and Crossmatching

Evaluation of IVAC Variable Pressure Volumetric Pump Model 560 for the delivery of red blood cells, adenine-saline added.

Mechanical pump systems for the delivery of intravenous solutions have been used for the transfusion of red blood cells. In this study, the IVAC Variable Pressure Volumetric Pump Model 560 was evaluated for that purpose using flow rates of 70 mL/hour and 999 mL/hour through 16-, 19-, and 23-gauge needles and an 18-gauge angiocatheter. The largest degree of hemolysis induced by the delivery system resulted in a mean increase of plasma hemoglobin of 150 mg/L (15 mg/dL); this is equivalent to the loss of 0.03% of the red blood cells. When programmed to deliver 15 mL of red blood cells, the IVAC 560 delivered 15.0 +/- 0.3 mL at a rate of 70 mL/hour and 14.9 +/- 0.3 mL at 999 mL/hour. The authors conclude that the IVAC 560 can be used to deliver red blood cells with a minimal, acceptable level of hemolysis. It also delivers an accurate and precise volume of red blood cells that may be an aid to the transfusionist.

Adenine

Multicompartment analysis of the effects of plasmapheresis. Application to lipid kinetics in humans.

The quantitative effect of plasmapheresis on concentrations of intravascular solutes is described by a minimal two-compartment model, which allows exit to and entry from a nonplasma body pool of the solute. This novel method is simple and capable of determining endogenous metabolic turnover of physiologically important plasma constituents in both therapeutic and experimental settings. The model was suggested by the therapeutic use of plasmapheresis in hyperlipidemia, and the turnover rates of triglyceride and cholesterol were calculated for one patient treated with chronic plasmapheresis. It is concluded that at least a two-compartment model is necessary to quantitatively describe the effect of plasmapheresis on any substance that undergoes appreciable endogenous turnover (metabolic clearance rate greater than 1.1 times plasmapheresis rate when both rates are in units of volume per time). Calculation of endogenous turnover rate with the use of measurements of the concentration of a solute in plasma before and after plasmapheresis and in the total plasmapheresate and measurement of the volume of plasma removed, volume of plasma substitute infused, and total plasmapheresis time is detailed. This method avoids the use of isotopic labeling experiments. In turn, the endogenous turnover rate may predict the efficacy of therapeutic plasmapheresis.

Blood Glucose

Preoperative crossmatch guidelines for total hip arthroplasty.

The use of crossmatch guidelines has become commonplace as a means of guiding surgeons to efficient preoperative blood ordering. To further refine existing guidelines for a major elective procedure, a number of specific characteristics of 175 patients who underwent 189 total hip arthroplasties were correlated with blood use by univariate and multivariate analyses. The findings of this study demonstrate that for patients with no detectable red cell alloantibody, four units of blood should be crossmatched and reserved preoperatively if the patient is undergoing exchange arthroplasty, or undergoing a transtrochanteric procedure. All other patients with no detectable red cell alloantibody should have two units of blood reserved preoperatively. Proper preoperative crossmatch ordering can result in more labor-efficient and thrifty use of transfusion services, as well as increased effectiveness of autologous predeposit programs.

Analysis of Variance

Transfusion therapy in emergency medicine.

Volume replacement is critical to the resuscitation of the hemorrhaging patient, but this usually can be accomplished quickly and safely with crystalloid and/or colloid solutions. Red cells should be used in addition to asanguinous fluids in the treatment of tissue hypoxia due to anemia. The need for whole blood as opposed to packed red blood cells is controversial. However, plasma should not be used as a volume expander, and its use to supplement coagulation factors during the massive transfusion of red cells should be guided by laboratory tests that document a coagulopathy. Similarly, platelet transfusions are indicated to correct documented thrombocytopenia or platelet dysfunction, and routine prophylaxis after fixed volumes of red cells results is unwarranted. Many anticipated complications of massive transfusions, including hemostatic abnormalities, acid-base imbalances, hyperkalemia, and hypocalcemia, are uncommon or of limited clinical significance. The risks of immune hemolysis and transfusion-transmitted diseases, on the other hand, are significant, and argue for judicious use of blood components. In emergencies in which blood is required immediately before compatibility testing can be completed, O-negative uncrossmatched blood can be requested. Careful blood specimen collection and patient identification prior to transfusion are critical. Practices that emphasize blood conservation, including the use of autologous salvaged blood, are always to the patient's advantage.

Blood Grouping and Crossmatching

A prospective comparison of platelet collection with the CS-3000 blood cell separator using the closed system and open system kits.

Each of 30 donors had two plateletapheresis procedures on the CS-3000 Blood Cell Separator (Fenwal Laboratories, Deerfield, IL). During one procedure, platelets were collected with the Closed System Apheresis Kit for Extended Platelet Storage (Fenwal); during the other procedure the Open System Apheresis Kit (Fenwal) was used. The same operator performed the entire collection process and all laboratory studies for both procedures for each donor. There was a statistically significant lower yield with the Closed System Kit (mean: 4.51 x 10(11) platelets) than with the Open System Kit (mean: 4.76 x 10(11) platelets) (P = 0.03). There was no significant difference in lymphocyte contamination. The relatively small magnitude of the difference, however, means that product quality, longer storage time, and cost are more important considerations in selecting a kit for use.

Blood Component Removal

Evaluation of adenosine triphosphate and 2,3-diphosphoglycerate after twenty-four hours in red cells washed for neonatal transfusion.

Adenosine triphosphate and 2,3-diphosphoglycerate concentrations in 14 U of CPDA-1 stored red cells (PRBC) and washed red cells (WRBC) were measured to assess indirectly the quality of WRBC for neonatal transfusion after 24 h. The results indicate that there is no difference in red cell ATP and 2,3-DPG concentrations between PRBC and WRBC after a 24-hour period.

2,3-Diphosphoglycerate

Lymphocyte subpopulations of plateletapheresis products collected with the Fenwal CS-3000 Cell Separator.

To determine whether any lymphocyte subset is preferentially harvested and transfused as a consequence of plateletapheresis with the Fenwal CS-3000 Blood Cell Separator, the proportions of lymphocyte subpopulations in platelet concentrates were compared to their proportions in the donors' peripheral venous blood immediately prior to platelet collection. There was no difference in the proportion of B cells (surface immunoglobulin positive), T cells (OKT3 positive), helper/inducer T cells (OKT4 positive), suppressor/cytotoxic T cells (OKT8 positive), and natural killer cells (Leu 7 positive) in the donors' peripheral venous blood and the plateletapheresis product. Thus, although previous studies have demonstrated the ability to separate lymphocyte subpopulations by density centrifugation and velocity sedimentation, plateletapheresis with the CS-3000 harvests the lymphocyte subpopulations studied in the same proportions in which they circulate in donors' peripheral venous blood.

Blood Component Removal