The effect of acute caffeine abstinence on microsurgical performance: A pilot randomised crossover study using a
Rui Niu1, Daniel Franks2, Christopha J Knee3
1Department of Orthopaedic Surgery, Port Macquarie Base Hospital, Port Macquarie, New South Wales, Australia.
Background:
Rapid alterations in coffee consumption may result in increased tremors affecting surgical performance. This pilot study aimed to assess the effect of acute caffeine abstinence relative to usual caffeine intake on microsurgical performance and to evaluate a custom-built mechanical model for future testing and training purposes.
Methods:
Decaffeinated and caffeinated beverages were consumed by eight blinded and fasted orthopaedic registrars. The registrars were then tasked with completing a task mimicking the skills inherent to microsurgery using a novel custom-built mechanical model. Outcomes assessed included total time to complete the task, as well as contact time between the suture needle and eyelet through which the needle was passed (as a surrogate for fine tremors and agitation), and were compared between decaffeinated and caffeinated conditions using the Wilcoxon signed-rank test.
Results:
Eight orthopaedic registrars (mean age 31.8 years) with an average of 11.3 prior microsurgery cases (range, 1-24) participated. The mean daily caffeine intake was 522.3 mg (range, 214-900 mg). Higher caffeine intake correlated with increased sleepiness on the Stanford Sleepiness Scale. Median (IQR) contact time was 1024 ms (304.5-1994.5) and 1018.5 ms (457-1527) for decaffeinated and caffeinated conditions, respectively. Median (IQR) total task time was 5620 ms (3939-6768) and 5412.5 ms (3745.3-5899.5), respectively. No significant differences were observed in contact time (median paired difference 58.5 ms, p = 0.23) or total task time (median paired difference 434.5 ms, p = 0.53).
Conclusion:
This preliminary pilot study did not detect a statistically significant difference in performance between participants who abstained from caffeine and those who consumed their usual amount. It also suggests the feasibility of a low-cost and replicable mechanical model to assess microsurgical performance for training or research purposes, although validation in larger cohorts is required.
