Surgical Endoscopy

, Volume 33, Issue 1, pp 216–224 | Cite as

Intraocular pressure increases after complex simulated surgical procedures in residents: an experimental study

  • Jesús Vera
  • Carolina Diaz-PiedraEmail author
  • Raimundo Jiménez
  • Jose M. Sanchez-Carrion
  • Leandro L. Di Stasi



Surgeons’ overload is one of the main causes of medical errors that might compromise patient safety. Due to the drawbacks of current options to monitor surgeons’ load, new, sensitive, and objective indices of task (over)load need to be considered and tested. In non-health-care scenarios, intraocular pressure (IOP) has been proved to be an unbiased physiological index, sensitive to task complexity (one of the main variables related to overload), and time on task. In the present study, we assessed the effects of demanding and complex simulated surgical procedures on surgical and medical residents’ IOP.


Thirty-four surgical and medical residents and healthcare professionals took part in this study (the experimental group, N = 17, and the control group, N = 17, were matched for sex and age). The experimental group performed two simulated bronchoscopy procedures that differ in their levels of complexity. The control group mimicked the same hand-eye movements and posture of the experimental group to help control for the potential effects of time on task and re-measurement on IOP. We measured IOP before and after each procedure, surgical performance during procedures, and perceived task complexity.


IOP increased as consequence of performing the most complex procedure only in the experimental group. Consistently, residents performed worse and reported higher perceived task complexity for the more complex procedure.


Our data show, for the first time, that IOP is sensitive to residents’ task load, and it could be used as a new index to easily and rapidly assess task (over)load in healthcare scenarios. An arousal-based explanation is given to describe IOP variations due to task complexity.

Graphical Abstract


Cognitive load Mental workload Patient safety Neuroergonomics Ocular biomarkers 



Research by LLDS was supported by the BBVA Foundation, Madrid, Spain (Grant No. 2015-2) and is currently supported by the Ramón y Cajal fellowship program (RYC-2015-17483). We thank IAVANTE staff (Andalusian Public Foundation for Progress and Health) for their help during data collection. We thank Dr. G. A. Koulieris (Inria, Université Côte d’Azur, France) for proofreading the paper.


This study was funded by the Campus of International Excellence (BioTic Granada) Research Programme (Research Project V7-2015 to CDP). The funding source had no role in the design or conduct of this study.

Compliance with ethical standards


Drs. Vera, Diaz-Piedra, Jiménez, Sanchez-Carrion, and Di Stasi have no conflicts of interest or financial ties to disclose.


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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Department of Optics, Faculty of ScienceUniversity of GranadaGranadaSpain
  2. 2.Mixed University Sport and Health Institute (iMUDS)University of GranadaGranadaSpain
  3. 3.Mind, Brain, and Behavior Research Center – CIMCYCUniversity of GranadaGranadaSpain
  4. 4.College of Nursing and Health InnovationArizona State UniversityPhoenixUSA
  5. 5.IAVANTE, Line of Activity of the Andalusian Public Foundation for Progress and Health, Ministry of Equality, Health and Social Policy of the Regional Government of AndalusiaGranadaSpain
  6. 6.Joint Center University of Granada - Spanish Army Training and Doctrine CommandGranadaSpain

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