This project was supported by Grant No. P60 AA007611-20 from the National Institute on Alcohol Abuse and Alcoholism. The contents of this report are solely the responsibility of the authors and do not necessarily represent the official view of the National Institute on Alcohol Abuse and Alcoholism or NIH.
Development and Pilot Validation of Computer-Assisted Self-Infusion of Ethanol (CASE): A New Method to Study Alcohol Self-Administration in Humans
Article first published online: 28 JUN 2008
Copyright © 2008 by the Research Society on Alcoholism
Alcoholism: Clinical and Experimental Research
Volume 32, Issue 7, pages 1321–1328, July 2008
How to Cite
Zimmermann, U. S., Mick, I., Vitvitskyi, V., Plawecki, M. H., Mann, K. F. and O’Connor, S. (2008), Development and Pilot Validation of Computer-Assisted Self-Infusion of Ethanol (CASE): A New Method to Study Alcohol Self-Administration in Humans. Alcoholism: Clinical and Experimental Research, 32: 1321–1328. doi: 10.1111/j.1530-0277.2008.00700.x
Present address: Department of Psychiatry and Psychotherapy, University Hospital Carl Gustav Carus (USZ, IM), Technische Universität Dresden, Dresden, Germany.
- Issue published online: 28 JUN 2008
- Article first published online: 28 JUN 2008
- Received for publication January 19, 2008; accepted March 28, 2008.
- Self Administration;
Background: Human alcohol self-administration studies employing oral intake are subject to high variability of the resulting blood alcohol concentrations because of idiosyncrasies of gastrointestinal absorption kinetics among subjects. We sought to improve the subjects’ opportunity to control their brain alcohol exposure by computer-assisted i.v. self-administration.
Methods: Instead of drinking, subjects could request increments of their arterial blood alcohol concentration (aBAC) of precisely 7.5 mg% at any time they wanted by pressing a button, provided their aBAC would not exceed 100 mg%. The latency between pushing the button and reaching the new aBAC peak was preset to be 2.5 minutes on the first day and was randomly changed to 1.5 or 3.5 minutes on days 2 and 3 in a crossover design. The necessary rate and amount of alcohol infusion was calculated by the software about once every second. Nine healthy social drinkers (4 females/5 males; mean age 25.0 ± 4.0 year) participated in 3 sessions each. Outcome measures were mean and maximum observed aBAC, and the number of alcohol requests.
Results: Maximum aBAC was 76.5 ± 26.3 mg% on average over all experiments. When grouping days 2 and 3 according to latency (1.5 vs. 3.5 minutes), maximum aBAC and the number of requests in the session were significantly higher with the faster rise and all 3 outcome measures were significantly correlated between days. No such correlations were found between the first and either of the following days.
Conclusions: These data suggest that CASE is practical and safe, and results in considerable alcohol exposure that can be manipulated with parameters chosen for the incremental exposure. Following 1 practice day, test–retest stability was good, suggesting a potential for use in scientific studies.