Related Experiment Videos
Relation between serum and whole-blood ethanol concentrations
1Department of Laboratory Medicine, Yale University School of Medicine, New Haven, CT 06510.
Clinical Chemistry
|November 1, 1993
Summary
This study presents an algorithm for converting serum ethanol to whole-blood alcohol concentrations, crucial for legal applications. The developed method accounts for individual ratio variations, enabling reliable estimations for legal evidence.
Area of Science:
- Forensic Toxicology
- Clinical Chemistry
Background:
- Legal statutes often define alcohol impairment based on whole-blood alcohol concentration (BAC).
- Interpreting serum ethanol concentrations requires accurate conversion to BAC due to physiological variations.
Purpose of the Study:
- To develop and validate an algorithm for estimating whole-blood alcohol concentration (BAC) from serum ethanol measurements.
- To establish confidence intervals for these estimations relevant to legal standards of evidence.
Main Methods:
- Determined serum:whole-blood alcohol concentration ratios in 211 patients.
- Analyzed the distribution of these ratios, including their logarithms.
- Calculated population ranges for the ratios at 99% and 95% confidence levels.
Main Results:
- Serum:whole-blood alcohol concentration ratios varied from 0.88 to 1.59, with a median of 1.15.
- Logarithms of the ratios followed a normal distribution, enabling parametric calculations.
- Established 99% (0.90-1.49) and 95% (0.95-1.40) population ratio ranges.
- The ratio was independent of serum alcohol concentration and hematocrit.
Conclusions:
- The proposed algorithm provides a statistically sound method for converting serum ethanol to BAC.
- The algorithm's confidence intervals can be directly related to legal standards of evidence.
- This approach offers a reliable tool for forensic and clinical toxicology applications.