What analytes on the i-STAT 1 system are measured and which are calculated? Measured: Hematocrit (Hct), Blood Urea Nitrogen (BUN), Creatinine (Crea), Ionized Calcium (iCa), Glucose (Glu), Chloride (Cl), Sodium (Na), Potassium (K), pH, Partial pressure of carbon dioxide (PCO2), Partial pressure of oxygen (PO2), Lactate, Activated Clotting time with Celite® activator (ACT), Cardiac Troponin I (cTnI) Calculated: Hemoglobin (Hb), Bicarbonate (HCO3), Total carbon dioxide concentration (TCO2), Oxygen saturation (sO2), Anion gap (AnGap), Base Excess (BE)ĭoes the i-STAT 1 require calibration? No. These ranges are available in the user guide provided with the analyzer. What species does the i-STAT 1 have reference ranges for? Cat, dog, and horse. What is the shelf-life of the i-STAT 1 cartridges? The cartridges are manufactured with 5-11 months shelf life, depending on the stability of the analytes in each cartridge. What type of sample is used? Whole blood. These cartridges are configured with parameters that can give a clear patient's condition depending on the clinical situation. What kinds of tests can be run on the i-STAT 1 instrument? The i-STAT 1 offers a variety of disposable, single-use cartridges (10) including tests for acid/base analysis, blood gases, chemistry, hematology, electrolytes, and some specialty tests like Lactate, ACT, and Cardiac Troponin I. This difference in signal is then converted to the specific concentration units for the analyte using the analyzer's internal processor. The concentration of the analyte is determined by measuring the difference in signal from the calibrant and the sample. The sensors are either potentiometric, measuring changes in the electric potential, amperometric, measuring changes in electric current, or conductometric measuring changes in conductivity. These coated sensors react to small changes caused by chemical reactions in the sample. A group of thin film electrodes located at the top of a cartridge are coated with chemically sensitive films. Measurement is accomplished using electrochemical sensing technologies.
Analytical evaluation of i-STAT portable clinical analyzer and use by nonlaboratory health-care professionals.What technology does the i-STAT 1 utilize? Electrochemistry. Jacobs E, Vadasdi E, Sarkozi L, Colman N. Bedside hemoglobin measurements: sensitivity to changes in serum protein and electrolytes. Anesth Analg 1993 76: 830–834Ī comparison of conductivity-based hematocrit determinations with conventional laboratory methods in autologous blood transfusions. Evaluation of STAT-CRIT hematocrit determination in comparison to Coulter and centrifuge: the effects of isotonic memodilution and albumin administration. A clinical evaluation of the hemocue haemoglobinometer using capillary, venons, and arterial samples. Lancet 1986 1: 307–310Ĭhen PP, Short TG, Leung DHY, Oh TE. Statistical methods for assessing agreement between two methods of clinical measurement. In summary, we found that in patients undergoing CPB, the iSTAT values agreed sufficiently well with standard laboratory values and that the iSTAT instrument can be relied upon for bedside measurements.īland JM, Altman DG. For all four tests (hematocrit, sodium, potassium, and glucose) the iSTAT had a similar relationship to the laboratory values as did the other commonly used means (centrifuge, BGE, and glucose meter) of clinical evaluation.
An alternative to measuring total protein and making the adjustment is simply adding 1 % to the hematocrit in the pre-CPB period and 3% on-CPB or post-CPB, which we found to yield values that differed from the laboratory by 0.52 ± 1.42 percentage points. The hematocrit values determined by the iSTAT machine, when adjusted for the level of total protein (according to manufacturer's directions), differed from the laboratory values by 0.53 = 1.46 percentage points. The means and standard deviations of the differences between the methods were calculated. Blood glucose concentration was measured by the hospital laboratory using a Kodak Analyzer and by a glucose meter, electrolytes were evaluated by the Kodak Analyzer and BGE (a device which is commonly used for “satellite laboratory” determinations of electrolyte and blood gas results), and hematocrit samples were measured by the hospital laboratory using an NE 8,000 and a centrifuge. after initiation of CPB, and following heparin neutralization by protamine. In addition to using the iSTAT analyzer, blood samples were analyzed at four time points: following induction of anesthetic, 10 min. Forty patients scheduled for elective CPB were evaluated prospectively. To evaluate the utility of the iSTAT blood analyzer, a bedside device for hematocrit, sodium, potassium, and glucose measurement during cardiopulmonary bypass (CPB).