[Medical assessment in suspected inability to drive a motor vehicle]. / Die ärztliche Untersuchung bei Verdacht auf Fahrunfähigkeit.

In questions of impaired driving, the expert statements of opinion are based primarily on the medical findings of the doctor involved. A proper medicolegal evaluation--and, as a consequence, the consistent legal evaluation of the event--depend entirely on the quality of this "statement by witness" on the actual psychophysiological condition of the accused motor vehicle driver. The Zurich Institute for Legal Medicine therefore developed a standardised method for the professionalisation of the medical examination of unfit drivers, such as those under the influence of drugs/medication, low levels of alcohol or fatigue. Based on literature searches, empirical knowledge and practical tests, a new medical examination procedure including a form was designed, which essentially includes an examination of the skin and the mucous membranes, a careful examination of the eyes, several tests of "divided attention" and the documentation of anomalies in the area of behaviour, mood and speech. The new procedure stands for a proper, performance-oriented strategy in the detection of impaired drivers.

[Driving fitness/driving capacity of patients treated with methadone]. / Beitrag zur Frage der Fahrfähigkeit/Fahreignung Methadonsubstituierter.

To answer the question whether or not therapeutic methadone doses significantly reduce traffic-related performance of drivers on medically supervised methadone programmes, 34 methadone substitution patients, all of them volunteers, were subjected to a test series: the focus of the study was a psychophysical test battery consisting of 10 individual performance tests to assess essential functions with regard to driving ability, such as concentration, attention, reaction capability, memory, perception and sensorimotor coordination. In evaluating the results of the psychophysical tests, multiple drug use and subjective methadone influence at the time of the examination were taken into consideration but current methadone blood level was neglected. The results were compared to those of a control group. The methadone group (n = 34) consisted of 25 men and 9 women aged between 18 and 38. At the time of the study, the majority of the test persons (29) were on low dosage methadone maintenance (up to 60 mg/day). In the urine samples of approximately 2/3 of the test persons, evidence was found for multiple drug use together with other psychotropic substances, the most frequent (14) being cannabis metabolites. Referring to their driving practices, a mere 4 out of 29 drivers had not committed any driving offences. A comparison of the psychophysical performance of the whole methadone group (n = 34) with a control group demonstrated that the methadone substitution patients achieved rather lower results in almost all variables. These performance deficits were particularly conspicuous in sustained attention, sensorimotor coordination and reaction capability. 12 "methadone only" participants, i.e. methadone probands without any additional consumption of psychotropic substances showed-partly considerably-better performance than the methadone group as a whole and also achieved normal results in relation to the test norm. Nevertheless, once again, results tended to be of lower level in comparison to the control group. "Methadone only" substitution patients, in particular those volunteers without a current subjective methadone influence-reached practically the same results as the corresponding control subjects, or at least average results based on test norm. However, the study revealed distinctive performance impairment (e.g. in sustained attention, reaction capability) when other psychotropic substances (including alcohol and cannabis!) were taken as well during the subjective methadone phase. The performance deficits were predominantly caused by a slowing down of reactions. Our study illustrates that, under certain conditions, long-term methadone maintenance under strict medical supervision does not have any significant unfavourable impact on the psychophysical performances in driving ability as examined in this study. Thus, these research findings support the previous Zurich experiences, according to which driving ability--and in the end also driving aptitude--of the methadone substitution patients does not depend on the methadone therapy itself, nor on the amount of the daily methadone intake. In making the final medical judgement on driving ability, the presence of a mixed drug use and the personality of the person in question are of far greater importance.

Impact of melatonin on driving performance.

BACKGROUND: Because millions of people are self-prescribing melatonin for various indications, the safety aspects of this substance have become very important. The aim of our study was to determine whether or not melatonin impairs driving-related performance. METHODS: Twenty healthy men and women aged 21-57 years volunteered for this randomized, placebo-controlled, double-blind, crossover study. The crossover arms were separated by an interval of at least 4 weeks. On each testing day, melatonin 5 mg or placebo was taken at 1630 h; 60 minutes later a test series was performed, consisting of a medical examination, body sway measurement, and a standardized driving computer test battery to assess attention, reaction time, power of concentration, and sensomotor coordination. Subjective sleepiness was measured on three occasions during the test session using the Stanford Sleepiness Scale questionnaire. RESULTS: Just one of the 16 main variables of the driving computer test battery, the selective attention tested by signal-detection, was significantly affected by melatonin (p < .05). However, even those values were still within the normal range. Subjective sleepiness was increased by melatonin, although the result was significant only after the prolonged concentration task (p < .05). Neither the clinical examination nor the body sway test showed signs of any drug influence. CONCLUSIONS: The overall result of the computer test battery showed no objective adverse impact of melatonin on driving performance. However, due to the increased subjective sleepiness after administration of this hormone, caution should be exercised when driving under the influence of melatonin.

[Problems in traffic medicine in hospital and everyday practice: able to drive?]. / Verkehrsmedizinische Fragestellung in Spital- und Praxisalltag: Fahrfähig?

On account of the right to mobility on the one hand and increased necessity for traffic safety on the other, physicians are more and more required to enhance involvement in traffic medicine. By the means of competent and professional acting, physicians should preventively contribute to traffic, safety [i.e. by informing about the influence of medical treatment on driving ability]. It is a matter of public interest to medically trace drives not able to drive. Proof of driving inability presupposes carefully done, standardized and reproducible clinical examination, along with the correct sampling of blood and urine. The knowledge of the most common pharmaceutical substances' effects on relevant traffic-related psycho-physical performances ensures timesaving medical examination and, due to the possibility to carry out more specific chemical analyses, important minimalization of the costly chemical analyses and therefore to less overall expenses. Finally, standardized proceeding makes possible medical realization of social responsibility and therefore improves jurisdiction.