Recent research has indicated that substantial differences may exist between the concentration of organic bases in heart blood specimens and that in peripheral blood specimens. This study was designed to determine the distribution characteristics of ethyl alcohol in postmortem blood. The heart blood/femoral blood ethyl alcohol ratio was determined for 100 cases. In the majority of cases exhibiting alcohol concentration differences greater than 0.02 mg/dL, the specimens were suspect because of their physical appearance, trauma to the decedent in the area of specimen collection, gross differences in hematocrits, or large volume differences in the two specimens. An additional set of experiments was conducted to illustrate that the volume of blood and the amount of sodium fluoride preservative placed in the collection tube can have a substantial effect upon the subsequently measured ethyl alcohol concentration. These factors can adversely affect the observed heart blood/femoral blood alcohol ratio and must be considered when evaluating the distribution characteristics of ethyl alcohol in postmortem specimens.

Blood Specimen Collection↗

PubMedDate not supplied

A simplified procedure for the isolation, characterization, and identification of weak acid and neutral drugs from whole blood.

The presented method utilizes commercially available Chem Elut columns for the extraction of weak acid and neutral drugs. The residue from this extraction is purified by partitioning between hexane and acetonitrile. The drugs are analyzed using a gas chromatograph equipped with a 0.53-mm i.d. dimethyl silicone capillary column, a packed column inlet adapter, and a flame ionization detector. The drugs are characterized by their retention index. The procedure is rapid, and clean chromatograms are the rule with essentially no lipid interference for flame ionization or mass spectrometer detection systems. The retention index has proven to be a very reliable parameter for describing chromatographic behavior. For probarbital, the internal standard, the calculated retention index averaged 1529.70 with a standard deviation of 1.27 index units (n = 115).

Acids↗

PubMedDate not supplied

A simplified procedure for the determination of free codeine, free morphine, and 6-acetylmorphine in urine.

A procedure for detection and quantification of free codeine, free morphine, and 6-acetylmorphine in urine is presented. The analytes were extracted at neutral pH by solid-phase extraction prior to derivatization to their trifluoroacetyl derivatives. The derivatized extracts were analyzed by gas chromatography/mass spectrometry in the electron impact mode. Confirmation of the analytes was accomplished by comparing the ion abundance ratios of the analytes to those of a previously analyzed standard. The qualitative ion abundance ratios were required to be within 20% of those of the standard for acceptance. Quantification was based on the tri-deuterated analogs of the analytes. Linearity was obtained in the range of 10 to 1000 ng/mL, with correlation coefficients of all analytes exceeding 0.999. Percent recoveries were 90% for codeine, 88% for morphine, and 85% for 6-acetylmorphine. No hydrolysis of 6-acetylmorphine occurs during the extraction procedure. The authors also studied the stability of 6-acetylmorphine at various storage conditions of pH, temperature, and chemical preservation. 6-Acetylmorphine was found to be stable for 12 weeks when stored at -17 degrees C.

Chemistry Techniques, Analytical↗

PubMedDate not supplied

The capillary gas chromatographic determination of trazodone in biological specimens.

A simple and specific method is presented for the capillary gas chromatographic determination of trazodone in postmortem blood and tissues. The drug and trimethobenzamide, which was used as an internal standard, were extracted with 1% isopropanol in n-butyl chloride. Chromatography was accomplished with a short (4-m) methyl silicone capillary column and hydrogen carrier gas. This combination of extraction solvent and chromatographic conditions was demonstrated to be both accurate and precise. Since trazodone is a relatively new drug, additional thin layer and packed column gas chromatographic data is presented to augment the incorporation of trazodone into routine analytical protocols.

Chromatography, Gas↗

PubMedDate not supplied

Concurrent use of salmeterol with inhaled corticosteroids is more effective than inhaled corticosteroid dose increases.

This randomized, double-blind, parallel, multi-center study was designed to determine whether the addition of salmeterol to existing inhaled corticosteroid therapy provides greater therapeutic benefit than doubling the dose of inhaled corticosteroids in symptomatic patients with asthma. A total of 514 adults were randomized to either beclomethasone 168 micrograms plus salmeterol 42 micrograms twice daily or beclomethasone 336 micrograms twice daily for 24 weeks. Both treatments resulted in significantly improved symptom control and increased pulmonary function. However, beclomethasone plus salmeterol provided greater improvements than doubling the dose of beclomethasone (p < or = 0.05) in FEV1 and in daily-recorded measurements of morning (38 L/minute versus 20 L/minute after treatment with higher dose beclomethasone) and evening peak expiratory flow, asthma symptom scores, symptom-free days, supplemental albuterol use, and days and nights not requiring albuterol. There were no significant differences between treatment groups in the number of patients with abnormal response to corticotropin stimulation at Treatment Week 24. No treatment differences in asthma exacerbation and adverse event frequency rates were seen. Beclomethasone 168 micrograms plus salmeterol 42 micrograms administered twice daily was superior to beclomethasone 336 micrograms taken twice daily in patients symptomatic on beclomethasone 168 micrograms, with no added safety risks.

Administration, Inhalation↗