The initial US patent (patent no. 3,604,815) for a reflectance glucose meter was assigned to Miles Laboratories, Inc, in 1971. This meter was based on the Ames Dextrostix, a dipstick using glucose oxidase and peroxidase to generate a blue color where the intensity was dependent on the glucose concentration. Developed for use in physician offices, the Dextrostix was good enough to distinguish hypoglycemia from hyperglycemia using a color intensity chart and the human eye. The initial Miles Reflectance Meter was designed to quantify color intensity of a Dextrostix using light reflectance. The process involved rinsing the strip with water, placing a blood sample on the stick for 50 seconds, washing with water again, blotting with a cotton ball, and then placing the strip into the meter that had a swinging needle indicator of the glucose concentration.1 Moreover, we worry about user error today. The initial meters were marketed to physician offices in the early 1970s, but eventually, patients began to advocate self-use, and the glucose meter industry was born. In the late 1970s and early 1980s, companies such as Boehringer-Mannheim (now Roche), Lifescan (J&J), Medisense (now Abbott), and Bayer also introduced meters. These companies continue to dominate the market and are often referred to as the “branded” meters. Before 1976, there was no premarket regulatory oversight of most medical devices, including glucose meters, in the United States. This changed with the Medical Device Amendment Act passed by the US Congress on May 28, 1976.

OBJECTIVES:The objective was to determine if emergency department (ED) patients with diabetes mellitus (DM) who have primary care providers (PCPs) have better control of their DM than patients with no PCPs.METHODS:This was a prospective, cross-sectional, observation study at a large, adult, urban, academic ED with 85,000 annual visits. ED patients with a history of DM were eligible. Patients with severe systemic disease, diabetic ketoacidosis (DKA), sepsis, active steroid use, pregnancy, or cognitive impairment were excluded. Consenting patients had hemoglobin A1c (HgbA1c) analysis and completed a questionnaire regarding demographics, lifestyle, medication usage, educational level attained, and health care access, including whether or not they had PCPs. HgbA1c levels were compared between subjects with and without PCPs using medians with interquartile ranges (IQRs). A continuous plot was developed to demonstrate the proportion of patients without PCPs (PCP-) compared to those with PCPs (PCP+) at every level of %HgbA1c across the entire measured range. Multivariate logistic regression analysis was used to determine which clinical and demographic factors obtained from the questionnaire were associated with improved glycemic control (increased relative risk [RR] of having a %HgbA1c < 8%).RESULTS:A total of 284 patients were screened; 227 were enrolled, had HgbA1c analysis performed, and had complete PCP, race, and sex information. Complete demographic data (insurance status, employment status, etc.) were available on 209 subjects. Sixty-four of the 227 patients (28.2%) denied having PCPs. Median HgbA1c was 7.7% (IQR = 6.5% to 9.68%) in PCP+ versus 8.9% (IQR = 6.8% to 11.3%) in PCP- patients (p = 0.01). Ninety-one of 163 (55.8%) PCP+ subjects had a median HgbA1c < 8% versus 25 of 64 (39.1%) in the PCP- group (p = 0.02). After adjusting for multiple clinical and demographic variables, having a PCP remained significantly associated with a median HgbA1c value less than 8% (RR = 1.43; p = 0.04).CONCLUSIONS:Diabetes control was significantly better in patients with PCPs, even after adjusting for a number of potentially confounding social and demographic factors.

Recent advances in medicine and technology, combined with an ever-growing workload, have increased the demand for skilled professionals in laboratory medicine. The specific need for trained physicians and scientists raises important questions about the content of training programs and about the ideal characteristics of the human products of the training programs. Excellent recent publications in several countries have addressed the scientific and technical components of training and the competencies that trainees are expected to develop. These publications will provide important guidance for training programs and for trainees for the foreseeable future. An additional goal of training is to produce members of a profession. These professionals will 1) aspire to meeting the challenges of the field with creativity, 2) be involved with the profession and the world and 3) function in a manner informed by their thorough grounding in professional and medical ethics. In the promising future of laboratory medicine, a focus on professional aspects is essential to meeting the potential of the field to contribute to health of the patients we serve.

Background: Ischemia can alter the ability of albumin to bind free metal atoms. Based on these biochemical changes, methods to quantify ischemia modified albumin (IMA) were developed to assist in the evaluation of patients with symptoms of cardiac ischemia. Since ischemia can occur in any vascular bed, the specificity of IMA for cardiac muscle ischemia is unclear and requires further investigation.Methods: We evaluated the specificity of an IMA test in patients with skeletal muscle ischemia during arthroscopic knee surgery. A pressurized thigh cuff was continuously inflated to 300 mm Hg on the operative leg, in order to arrest blood flow during the procedure. Samples were collected before surgery, 15 min after surgery, and prior to discharge.Results: Twenty-three patients were enrolled in the study. Median tourniquet time was 29 min (range 19-108). Median pre-operative IMA was 90.2 KU/I (range 77-101.6). Statistically significant (p < 0.05) increases in IMA and myoglobin concentrations, and decreases in albumin concentrations were observed following tourniquet release and before discharge.Conclusions: Post-operative myoglobin elevations indicated that skeletal muscle ischemia was sufficient to produce detectable myocyte necrosis. Post-operative IMA increases are consistent with ischemic modification of albumin during exposure to ischemic conditions in skeletal muscle during and/or immediately after tourniquet application. However, the negative correlations between IMA and albumin results suggest that increases in IMA were in part due to lower post-operative albumin concentrations resulting in decreased cobalt binding. (c) 2005 Elsevier B.V. All rights reserved.

Background: This study determines the analytical characteristics of the i-STAT cardiac troponin I assay (cTnI; i-STAT, Princeton, NJ), a 10-min POC assay, designed to be performed at the bedside. Methods: Three different hospitals participated in a patient specimen and analytical validation study (n=186) for the i-STAT cTnI assay carried out in real time. A total of 186 whole blood specimens (lithium heparin) were collected from patients presenting with symptoms suggestive of acute coronary syndromes (ACS) for correlation studies as well as from 162 healthy subjects for reference interval determination. Factors studied included antibody specificity, detection limit, imprecision, linearity, assay specificity, sample type stability, interferences, reference limit determination and comparison vs. the Dade Stratus CS cTnI assay. Results: Total imprecision (CV) of 10% and 20% were seen at 0.09 and 0.07 μg/l, respectively. The detection limit was 0.02 μg/l. The 99th percentile reference limit was 0.08 μg/l. The assay was not affected by common interferents. An equimolar response within 5% was found for reduced and phosphorylated forms of TIC and IC complexes. Regression analysis for the i-STAT cTnI between whole blood and plasma specimens and for whole blood between the i-STAT and Stratus CS cTnI assays demonstrated slopes of 1.06 and 0.89, respectively. Conclusions: The i-STAT cTnI assay is a sensitive and precise monitor of cTnI, poised for point-of-care/near bedside clinical utilization for triage, diagnostics and risk management of acute coronary syndrome patients.

Study objectives: Diabetic ketoacidosis (DKA) is a common, life-threatening complication of diabetes. Immediate treatment is necessary to avoid rapid clinical deterioration and the need for higher levels of care. Patients presenting with elevated blood glucose levels have become so common in the emergency department (ED) that clinical suspicion of DKA may not be sufficient to discriminate the true metabolic emergency from less serious hyperglycemic conditions. Treatment delays are common because of nonclassic presentation and the need for laboratory test results to make the diagnosis of DKA. The diagnosis of DKA relies on signs and symptoms plus laboratory findings of blood glucose level greater than 250 mg/dL, an anion gap greater than 15 mmol/L, and carbon dioxide (CO2) level less than 20 mmol/L, excluding other, less common causes of anion gap acidosis. We compared the results of a point-of-care test for the ketone β-hydroxybutyrate (β-OHB) with standard measures for accuracy in predicting the diagnosis of DKA.Methods: After providing informed consent, 101 patients who presented with blood glucose greater than 250 mg/dL or clinical signs of DKA underwent testing for β-OHB at Barnes-Jewish Hospital ED triage using the Precision Xtra meter (Abbott Laboratories, North Chicago, IL). Additional diagnostic evaluation followed clinical guidelines but included a measured glucose and electrolyte panel in all cases. The diagnosis of DKA was made by experienced clinicians using standard clinical criteria. Logistic regression was used to identify clinical indicators of DKA, and χ2 analysis was used to evaluate binary decision rules.Results: Demographics of the study group include mean age 46.4±16.3 years (range 20 to 83 years); 45.1% female patients; 83.3% black patients, and 16.6% white patients (including 1 Asian and 1 Hispanic patient). The mean blood glucose level was 511±265 mg/dL (range 76 to 1,340 mg/dL); creatinine level 1.76±1.56 mg/dL (range 0.5 to 9.8 mg/dL); and anion gap level 15.7±8.7 mmol/L. A clinical diagnosis of DKA was made in 37 patients. Values of β-OHB ranged between 0 and 6 mmol/L (mean 1.86±2.12 mmol/L). The β-OHB values correlated with anion gap (0.614 mmol/L, P<.001), CO2 (–0.603 mmol/L, P<.001), and glucose level (0.292 mg/dL, P<.001). Adapting decision criteria recommended by the manufacturer, we tested a clinical decision rule using indicators of DKA available at triage: β-OHB and glucose (β-OHB <.6 mmol/L, patient at low risk for DKA; β-OHB >1.5 mmol/L, patient at high risk for DKA; β-OHB from 0.6 to 1.5 mmol/L with blood glucose >250 mg/dL, patient at intermediate risk of DKA). This decision rule was significantly related to DKA status (χ2=38.176, P<.001), with sensitivity of .949, specificity of .677, and overall correct classification rate of .782. Logistic regression analysis, including criterion standard clinical indicators of DKA (anion gap and CO2), implied a complex decision rule with sensitivity of .949 and specificity of .919. Additional logistic regression analysis, using only information available at triage (β-OHB and BG), showed that blood glucose level added little to classification of patients. Therefore, an alternate decision rule using only β-OHB was tested, in which β-OHB greater than 1.1 mmol/L was used as an indicator of DKA status. This decision rule left diagnostic sensitivity at .949, reduced specificity to .806, and provided an overall correct classification rate of .861 (χ2=54.66, P<.001).Conclusion: The point-of-care test for β-OHB was as sensitive as more established clinical indicators of DKA and offers immediate preliminary diagnosis of patients so that timely, critical interventions can be initiated.