SOFT 2004 Meeting Abstracts - Society of Forensic Toxicologists

B5
CORRELATION OF SALIVA AND BLOOD ESTAZOLAM CONCENTRATIONS WITH
BALANCE CHANGES IN SUBJECTS AFTER ADMINISTRATION OF THE DRUG AND/OR
ALCOHOL
Maria Kalal> Piotr Adamowicz l , Ewa Chudzikiewicz l , Wojciech Lechowicz l , Ewa Pufal 2 , Wojciech
Piekoszewski l , Karol Sliwka 2 : IInstitute of Forensic Research in Krakow; 2Department of Forensic
Medicine ofthe Medical Academy in Bydgoszcz
In 1992-1999, at the Institute of Forensic Research in Krakow, blood samples taken from 83 drivers
involved in road incidents tested positive for morphine. Benzodiazepines (BZD) were found in 60% of the
cases. In 2002-2003, the number of drivers under the influence of drugs involved in accidents was 166.
There was a high prevalence (65%) ofTHC and amphetamines detected. 17% of the population were under
the influence of morphine and other medications, and 23% tested positive for BZD. In 2002, 278 drivers
were questioned about driving a car after intake of a medicinal drug. 134 respondents reported driving a
car while taking a medicinal drug; 41% of them used BZD. Although the approach to the presence of
morphine, THC, cocaine and amphetamines in the blood of drivers should without doubt be one of "zerotolerance",
the situation concerning the legal limit for BZD is not so clear. .
On the basis of the results both of surveys and laboratory examinations, it can be stated that the BZD's
most often used in Poland are diazepam and estazolam. Therefore, estazolam was chosen as a model
substance for analysis of balance changes in persons influenced by the drug. The balance disturbance that
occurs at the legal limit (0.5 giL) ofalcohol in blood was used as a reference point.
Concentrations of estazolam in blood and saliva samples were determined by the LC-MS/APCI method
after LLE. Blood and saliva samples were taken from 25 healthy volunteers who received a single oral
dose of 1 mg of estazolam. The samples were collected every hour, for four hours. Half an hour before the
last sampling, volunteers received a dose of ethanol that led to a blood concentration of about 0.5g/1. On
the next day, the same volunteers received alcohol alone at the same dose, and a blood and saliva sample
was taken 0.5 h later.
The LC-MS/APCI method had the following validation parameters [ng/mLl: LOD - 0.33 and 0.63, LOQ ­
1.09 and 1.05, LOL - up to 200 and 20 for blood and saliva respectively.
The dose of estazolam produced average blood concentrations of 21, 24, 24 and 29 ng/mL, and saliva of
2.8, 1.9, 1.9 and 2.2 ng/mL at the respective sampling points. The correlation coefficient between blood
and saliva concentrations was 0.50.
For estimation of balance changes in persons influenced by estazolam, alcohol, and estazolam with alcohol,
posturography was used. Using the Langevin equation, the diffusion matrix and the friction coefficient
were calculated. For each of the tested persons, 8 stabilograms were obtained, two (with open and closed
eyes) for each of the four studied situations:· control (before estazolam or alcohol administration); after
intake of alcohol alone; 2 h after intake of estazolam alone; as well as after intake of ethanol together with
estazolam.
It was shown that the values of the friction coefficient decreased when persons kept their eyes closed,
1
from: 9.45 to 7.25 5. , 9.45 to 6.95 5. 1 and 9.83 to 6.77 5. 1 after administration of estazolam, alcohol, and
alcohol with estazolam respectively. These changes showed a trend when under the influence of estazolam
(P=0.078) and ethanol (P=0.057), but were statistically significant for estazolam with ethanol (P=0.036) as
compared to the placebo condition. The values of the friction coefficient after administration of alcohol
and estazolam did not differ statistically (P=0.677).
The results show that the friction coefficient can be used as an indicator that allows us to assess if a person
is under the influence of a medicine that disturbs hislher balance.
Keywords: Estazolam, Friction Coefficient, Posturography.
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