Spurious automated red cell values in warm autoimmune hemolytic anemia

Two patients with warm autoantibodies to their red cells had a mean cell volume artifactually elevated by red cell agglutination. Red cell size distribution histograms directly showed doublets and triplets of normal-size red cells. This phenomenon is similar to the spurious macrocytosis previously reported due to cold agglutinins, but was not reversible by warming.     

Insulin in the management of the diabetic surgical patient: continuous intravenous infusion vs subcutaneous administration

A prospective randomized study comparing constant intravenous infusion of regular, low-dose insulin versus conventional subcutaneous administration of neutral protein Hagedorn (NPH) insulin in insulin-requiring patients undergoing orthopedic procedures under general anesthesia was undertaken. The degree of diabetic control was better in those receiving constant 2 units/hour of regular insulin than in those receiving two thirds of daily maintenance doses of NPH insulin. However, in two of eight patients receiving 2 units/hour, decreased insulin infusion rates and increased dextrose infusion rates were required to avoid hypoglycemia. Preoperative NPH insulin and 1 unit/hour insulin administration resulted in equivalent diabetic control.     

A Rapid Nonenzymatic Assay for 2,3-DPG in Multiple Specimens of Blood

A simple, sensitive method of measure for D-2,3-diphosphoglyceric acid (2,3- DPG), which readily lends itself to the analysis of multiple samples, is reported herein.

Phosphate content of the red blood cells (RBC) represents approximately 64% 2,3- DPG, 26% adenosine nucleotides, and 3% inorganic phosphate. The remaining phosphate-containing compounds account for less than 10% of the total phosphate. With this method trichloroacetic acid filtrates of RBC are treated with charcoal to remove nucleotides and analyzed for inorganic and total (hydrolyzable) phosphorus. The difference between these measurements is considered 2,3-DPG. The residual phosphorus is equivalent to less than 10% of the total phosphorus and represents less than 0.6µ.mol when equated as 2,3-DPG. With this method, the mean level for 20 control subjects was 5.22µmol (SD 0.880) as compared to Krimsky’s method with a mean level of 4.95µmol (SD 0.847).     

Hospitalists and an innovative emergency department admission process

After treatment in an emergency department (ED), patients often wait several hours for hospital admission, resulting in dissatisfaction and increased wait times for both admitted and other ED patients. We implemented a new direct admission system based on telephone consultation between ED physicians and in-house hospitalists. We studied this system, measuring admission times, length of stay, and mortality. Postintervention, admission times averaged 18 minutes for transfer to the ward compared to 2.5 hours preintervention, while pre- and postintervention length of stay and mortality rates remained similar.     

The Prognostic Significance of Troponin I and Troponin T

Abstract. Objectives : To determine and compare the prognostic abilities of early, single-sample measurements of cardiac troponin I (cTn-I), cardiac troponin T (cTn-T), creatine kinase-MB (CK-MB) among ED patients with possible myocardial ischemia. Methods : Prospective collection of clinical and serologic data using an identity-unlinked technique from patients with possible myocardial ischemia at 2 urban EDs. Outcome data concerning the occurrence of adverse events (AEs) during the 14 days after enrollment were used to calculate and compare the relative risks (RRs) and predictive values (with 95% confidence intervals) of the 3 markers for predicting AEs. Results : Among the 401 study patients, 105 AEs occurred in 67 patients. cTn-I, cTn-T, and CK-MB were all significantly predictive of AEs, with RRs of 3.87 (2.39, 6.26), 3.03 (1.92, 4.79), and 6.45 (4.74, 8.77), respectively. For prediction of AEs, sensitivity for each of the 3 markers was low (cTn-I = 15.38, cTn-T = 24.62, CK-MB = 15.38), while specificity was high (cTn-I = 97.62, cTn-T = 93.15, CK-MB = 99.70). No significant difference in predictive ability was found between cTn-I and cTn-T. However, a positive CK-MB result was a stronger predictor of AEs than either cTn-I (p = 0.01) or cTn-T (p = 0.001). Conclusions : No significant difference in predictive abilities was found between cTn-I and cTn-T. However, routine testing for both CK-MB and either of the troponins may optimize early identification of high-risk patients so they may be targeted for a higher level of care and consideration of more aggressive therapies.