[Usefulness of the initial medical examination on matters relating to persons suspected of driving under the influence of amphetamine and its analogs or delta9-tetrahydrocannabinol based on the materials the Department of Forensic Medicine, Pomeranian Medical University in Szczecin].

Abstract

Introduction: Polish law forbids persons to drive under the influence of intoxicating substances, and those after the use of substances producing effects similar to alcohol. Therefore, there is a need to give an opinion based on a blood test, to establish whether or not the person from whom the blood was taken was under the influence of an intoxicating substance or after use of the drug while driving. Some authors reported that the final opinion should take into account chemical and toxicology test results identifying the parent compound and/or the metabolite only, but also the sampling time of the material to be analyzed in relation to the driving time, the result of the medical examination conducted prior to the collection of material for analysis, and the results of screening tests executed at the scene. Circumstances relating to the event, the findings and observations of third parties, and the testimony of the suspect are also relevant. The aim of this study was to evaluate the results of the medical examination in the evaluation of cases concerning driving by persons who were potentially under the influence of amphetamine and its analogs, or delta9-tetrahydrocannabinol, (delta9-THC) and conformity assessment of these results with the results of blood tests. An additional aim was to determine the factors considered by doctors when making their evaluation of patient's condition.

Material and methods: The study group consisted of 350 persons suspected of driving while under the influence of amphetamine and its analogs, and/or delta9-THC, from whom blood samples were taken to test amphetamine content or its analogues and/or delta9-tetrahydrocannabinol. Blood tests were carried out according to the existing procedure developed by the department. Blood samples were initially analyzed with immunochemical methods. Positive preliminary results were verified by gas chromatography-mass spectrometry. Statistical analysis was conducted with independent tests for multi-way tables, i.e. the Pearson chi2 test and the 2 x 2 tables Yates' correction was used for the low numbers. Comparison of mean concentrations of amphetamine and delta9-THC in the blood was performed using the U Mann-Whitney test.

Results: The analysis revealed a significant correlation between the symptoms and the results of the chemical-toxicological blood tests for mood only. There was no significant correlation between the results of toxicological and physical elements contained in the protocol of blood collection as the skin's appearance, speech, heart rate, pupil, pupil reaction to light, walking, lifting objects off the ground, the Romberg test, the finger-to-nose test and orientation in the space time environment. In the analysis of the relationship between the medical assessment and physical elements significant relationships with the assessment of mood, pupils, pupil reaction to light and gait were found. A significant correlation between the prevalence of symptoms in terms of any/none and medical evaluation was found.

Conclusions: 1. Preliminary medical examination based on the blood sampling protocol has no practical importance for determining whether a person is tested under the influence of amphetamines or its analogues and/or delta9-THC. 2. The confirmation of the state "under the influence of narcotics or psychotropics" should only be based on blood test results. 3. Doctors, when completing the blood collection report, are often guided by factors other than the test results when making assessment. 4. The low utility of the medical examination is affected by lack of standardization of test items. Doctors often find symptoms in a subjective manner.