PubMed Health⌕ Search
Home/Archive/PubMed

PubMed · 10048893

An alternate method for calibrating the thromboelastograph.

S E McNulty·D P Maguire·L D Arai
View original source ↗Export metadata ↓

Abstract

OBJECTIVE: This study evaluated various substances that could be used to calibrate the Thrombelastograph. DESIGN: Prospective, controlled comparison. SETTING: Operating room laboratory at a tertiary care university hospital. PARTICIPANTS: None. INTERVENTIONS: Six substances commonly available in the operating room setting (ointments, creams, and gels) were analyzed by thromboelastography for 3 minutes. Sixty measurements were made for each substance. MEASUREMENTS AND MAIN RESULTS: Thromboelastographic analysis of the ointments and cream preparations had an amplitude variability that exceeded 10 mm within the 3-minute recording period. The conductive gel had the most reproducible thromboelastography tracing with a mean amplitude of 62.5 +/- 1.1 mm (analysis of variance, p < 0.0005). There was a significant correlation between the reported viscosity of the three gels and the deflection amplitude (linear regression, R2 = 0.97; p < 0.0001). CONCLUSION: Conductive gel is a useful substance for quickly checking the functional status of the Thrombelastograph at an operational stage. Calibration of the Thrombelastograph using a gel of known viscosity is clinically relevant and may be more practical than testing with thromboelastographic-defined normal and abnormal blood analogs.

Explore related subjects

CalibrationGelsOintmentsProspective StudiesThrombelastographyViscosityJournal Article

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

S E McNulty, D P Maguire, L D Arai. 1998. An alternate method for calibrating the thromboelastograph.. https://doi.org/10.1016/s1053-0770(98)90234-8

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed2002

Quantification of isoflavones in red clover by high-performance liquid chromatography.

An RP-HPLC method for the determination of daidzein, genistein, formononetin and biochanin A in red clover (Trifolium pratense L.) was developed and validated. The compounds are quantified after hydrolytic extraction using an internal standard. On a base-deactivated C(18) column good separation of the analytes, also from accompanying substances, and excellent peak shape are achieved by gradient elution with aqueous sulfuric acid and acetonitrile. The method was applied to the analysis of different red clover cultivars.

Calibration↗
PubMed2002

Concept of sequential analysis of free and conjugated phytosterols in different plant matrices.

A unique concept and method for the determination of the total plant sterol content as sum of free sterols (FS), steryl esters (SE), steryl glycosides (SG) and acylated steryl glycosides (ASG) in different plant materials (pumpkin seeds, lecithins) and phytopharmaceuticals derived thereof, was developed. For this purpose, a multidimensional sample clean-up protocol based on efficient solid-phase extraction materials was elaborated and the SG were isolated employing a novel phenyl boronic acid modified silica gel material. Along this line also a set of steryl glucosides was synthesised and employed as internal standard and for calibration in the course of quantitative analysis. Final quantification of SG was carried out with reversed-phase HPLC in combination with evaporative light scattering detection (ELSD); the ASG were determined after conversion to SG by mild alkaline hydrolysis. In order to determine the total plant sterol profile the sum of FS and SE was additionally analysed from the unsaponifiable lipid fraction by GC-FID. The yields obtained from recovery tests for the determination of SG using soya lecithin as matrix to which 2, 20 and 40 mg/g of cholesterol-beta-D-glucoside was added were 99.10, 98.07 and 90.00%, and the RSDs were 4.11, 2.62 and 4.50%, respectively. Application related to the qualitative and quantitative analysis of total phytosterol profiles in different plant matrices and extracts demonstrate the validity of the method.

Calibration↗
PubMed2002

Evaluation of a high-resolution time-of-flight mass spectrometer for the gas chromatographic determination of selected environmental contaminants.

A benchtop high-resolution time-of-flight mass spectrometer (TOF MS) was evaluated for the determination of key organic microcontaminants. The major advantage of the TOF MS proved to be the high mass resolution of about 0.002 Da (10 ppm). Consequently, the detectability of polar pesticides, polynuclear aromatic hydrocarbons and polychlorinated biphenyls is excellent, and detection limits are in the order of 1-4 pg injected mass. Best mass spectral resolution was obtained for medium-scale peaks. It is a disadvantage that the calibration range is rather limited, viz. to about two orders of magnitude. The high mass spectral resolution was especially useful to improve the selectivity and sensitivity when analyzing target compounds in complex samples and to prevent false-positive identifications.

Calibration↗