The Use of Caffeinated Substances by Surgeons for Cognitive Enhancement

Andreas G. Franke, MD, PhD, MA; Christiana Bagusat, Dipl-Soz; Carolyn McFarlane; Teresina Tassone-Steiger; Werner Kneist, MD; Klaus Lieb, MD


Annals of Surgery. 2015;261(6):1091-1095. 

In This Article

Abstract and Introduction


Objective: To investigate the use of coffee, caffeinated drinks, and caffeine tablets for pharmacological cognitive enhancement (CE) among surgeons.

Background: Surgeons have demanding workloads, and the resulting fatigue and concentration deficits can lead to medical errors. Some surgeons use substances that promote wakefulness to counteract these effects.

Methods: A total of 3306 surgeons who attended 5 international conferences in 2011 were surveyed regarding their use of coffee, caffeinated drinks, and caffeine tablets for CE and potential factors derived from professional and private life using an anonymous self-report questionnaire. In this study, we were only interested in surgeons working in hospitals; therefore, 951 questionnaires were statistically analyzed.

Results: The most prevalent reason for using caffeine of any kind was to reduce fatigue (54.3%). Further prevalent reasons are working the night shift (32.2%) and overly long and excessive work hours (31.7%). Lifetime, past-year, past-month, and past-week prevalence was 66.8%, 61.9%, 56.9%, and 50.5%, for coffee use; 24.2%, 15.4%, 9.9%, and 6.1%, for caffeinated drinks; and 12.6%, 5.9%, 4.7%, and 3.8%, respectively, for caffeine tablets. Caffeine use was associated with lower age, male sex, divorced marital status, living with children, lack of satisfaction with professional status, pressure to perform in private life, and pressure perceived to be harmful to one's own health.

Conclusions: Surgeons often use caffeinated substances to cope with fatigue and long working hours. Coffee use was more prevalent than the use of caffeinated drinks and caffeine tablets.


Coffee is a widespread used beverage. A small representative study in the United States found that 96% of adults have ever used caffeine.[1] That study found that 83% of the inhabitants of a small city use caffeinated beverages weekly, and 61% of these participants also use caffeinated beverages other than coffee.[1] In a US random digit dialling survey of 2714 participants ages 25 to 74 years, 78% stated that they drink caffeine on a regular basis; only 15% stated that they had never drunk coffee.[2] Reasons for this use have not yet been systematically assessed. Being a flavoring substance coffee is an integral part of our culture. Furthermore, caffeine is used for cognitive enhancement (CE) purposes: A previous study of our group revealed that, among students, 53% already used (lifetime prevalence) coffee, 39% caffeinated drinks, and 11% caffeinated tablets for the purpose of CE.[3] Previous clinical studies showed that caffeine use increases vigilance and alertness and improves simple cognitive skills (eg, psychomotor skills). Caffeine is effective in boosting psychomotor and simple cognitive skills, especially in situations in which people are subjected to prolonged wakefulness and sleep deprivation.[4–6] A recent experimental study examined the effects of caffeine and taurine (ie, energy drinks) among sleep-deprived surgeons and revealed that study revealed that participants receiving caffeine needed less time for surgery, had better reaction time, and were more economic regarding their movements during laparoscopic surgery. Caffeine restored psychomotor performance to rested levels.[7]

Physicians in general are often exposed to excessive workload, leading to mental and physical exhaustion, fatigue, and sleep deprivation (especially during night shifts),[8–10] which may increase the likelihood of medical errors.[7,11–16] Therefore, surgeons may try to counteract states which may lead to medical errors (eg, fatigue, sleep deprivation, concentration deficits, etc). In this respect, Warren et al theoretically discussed "the neurocognitive enhancement of surgeons."[17] The epidemiology of caffeine among employees with excessive workload, shift work, and further extreme working conditions, such as surgeons, has not yet been assessed in detail. Therefore, we assessed the use of coffee, caffeinated drinks, and caffeine tablets exclusively for CE purposes among surgeons working in hospitals and factors associated with its use, including the conditions of private and professional life, using anonymous questionnaires.