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Surgical Endoscopy

, Volume 26, Issue 10, pp 2746–2750 | Cite as

Workload assessment of surgeons: correlation between NASA TLX and blinks

  • Bin Zheng
  • Xianta Jiang
  • Geoffrey Tien
  • Adam Meneghetti
  • O. Neely M. Panton
  • M. Stella Atkins
Article

Abstract

Background

Blinks are known as an indicator of visual attention and mental stress. In this study, surgeons’ mental workload was evaluated utilizing a paper assessment instrument (National Aeronautics and Space Administration Task Load Index, NASA TLX) and by examining their eye blinks. Correlation between these two assessments was reported.

Methods

Surgeons’ eye motions were video-recorded using a head-mounted eye-tracker while the surgeons performed a laparoscopic procedure on a virtual reality trainer. Blink frequency and duration were computed using computer vision technology. The level of workload experienced during the procedure was reported by surgeons using the NASA TLX.

Results

A total of 42 valid videos were recorded from 23 surgeons. After blinks were computed, videos were divided into two groups based on the blink frequency: infrequent group (≤6 blinks/min) and frequent group (more than 6 blinks/min). Surgical performance (measured by task time and trajectories of tool tips) was not significantly different between these two groups, but NASA TLX scores were significantly different. Surgeons who blinked infrequently reported a higher level of frustration (46 vs. 34, P = 0.047) and higher overall level of workload (57 vs. 47, P = 0.045) than those who blinked more frequently. The correlation coefficients (Pearson test) between NASA TLX and the blink frequency and duration were −0.17 and 0.446.

Conclusion

Reduction of blink frequency and shorter blink duration matched the increasing level of mental workload reported by surgeons. The value of using eye-tracking technology for assessment of surgeon mental workload was shown.

Keywords

Endoscopy training Simulation Mental workloads Eye-tracking Surgical education Patient safety 

Notes

Acknowledgments

We thank the Canadian Natural Sciences and Engineering Research Council (NSERC) and the Royal College of Physicians and Surgeons in Canada (RCPSC) Medical Education Research Grant for funding this project.

Disclosures

Dr. Neely Panton receives funds from Ethicon Endo-Surgery for fellow education and is on the scientific advisory board of Ethicon Endo-Surgery. Dr. Bin Zheng, Xianta Jiang, Geoffrey Tien, Dr. Adam Meneghetti, and Dr. Stella Atkins have no conflicts of interest or financial ties to disclose.

References

  1. 1.
    Tendick F, Jennings RW, Tharp G, Stark L (1993) Sensing and manipulation problems in endoscopic surgery: experiment, analysis, and observation. Presence 2:66–81Google Scholar
  2. 2.
    Keehner MM, Tendick F, Meng MV et al (2004) Spatial ability, experience, and skill in laparoscopic surgery. Am J Surg 188:71–75PubMedCrossRefGoogle Scholar
  3. 3.
    Cuschieri A (1995) Visual displays and visual perception in minimal access surgery. Semin Laparosc Surg 13:209–214Google Scholar
  4. 4.
    Berguer R, Chen J, Smith WD (2003) A comparison of the physical effort required for laparoscopic and open surgical techniques. Arch Surg 138:967–970PubMedCrossRefGoogle Scholar
  5. 5.
    Berguer R, Smith WD, Chung YH (2001) Performing laparoscopic surgery is significantly more stressful for the surgeon than open surgery. Surg Endosc 15:1204–1207PubMedCrossRefGoogle Scholar
  6. 6.
    Klein MI, Warm JS, Riley MA, Matthews G, Gaitonde K, Donovan JF (2008) Perceptual distortions produce multidimensional stress profiles in novice users of an endoscopic surgery simulator. Hum Factors 50:291–300PubMedCrossRefGoogle Scholar
  7. 7.
    Carswell CM, Clarke D, Seales WB (2005) Assessing mental workload during laparoscopic surgery. Surg Innov 12:80–90PubMedCrossRefGoogle Scholar
  8. 8.
    Cao CG (2007) Guiding navigation in colonoscopy. Surg Endosc 21:480–484PubMedCrossRefGoogle Scholar
  9. 9.
    O’Connor A, Schwaitzberg SD, Cao CG (2008) How much feedback is necessary for learning to suture? Surg Endosc 22:1614–1619PubMedCrossRefGoogle Scholar
  10. 10.
    Stefanidis D, Haluck R, Pham T et al (2007) Construct and face validity and task workload for laparoscopic camera navigation: virtual reality versus videotrainer systems at the SAGES Learning Center. Surg Endosc 21:1158–1164PubMedCrossRefGoogle Scholar
  11. 11.
    Zheng B, Cassera MA, Martinec DV, Spaun GO, Swanstrom LL (2010) Measuring mental workload during the performance of advanced laparoscopic tasks. Surg Endosc 24:45–50PubMedCrossRefGoogle Scholar
  12. 12.
    Ryu K, Myung R (2005) Evaluation of mental workload with a combined measure based on physiological indices during a dual task of tracking and mental arithmetic. Int J Ind Ergon 35:991–1009CrossRefGoogle Scholar
  13. 13.
    Andreassi JL (2000) Psychophysiology: human behavior and physiological response, 4th edn. Lawrence Erlbaum Associates, LondonGoogle Scholar
  14. 14.
    Marshall SP (2007) Identifying cognitive state from eye metrics. Aviat Space Environ Med 78:B165–B175PubMedGoogle Scholar
  15. 15.
    Caffier PP, Erdmann U, Ullsperger P (2003) Experimental evaluation of eye-blink parameters as a drowsiness measure. Eur J Appl Physiol 89:319PubMedCrossRefGoogle Scholar
  16. 16.
    Benedetto S, Pedrotti M, Minin L, Baccino T, Re A, Montanari R (2011) Driver workload and eye blink duration. Transp Res F 14:199–208CrossRefGoogle Scholar
  17. 17.
    Smith P, Shah M, Lobo NDV (2000) Monitoring Head/Eye Motion for Driver Alertness with One Camera. In: Proceedings of the 15th international conference on pattern recognition (ICPR’00), Barcelona, Spain, 3–7 September 2000Google Scholar
  18. 18.
    Veltman JA, Gaillard AWK (1998) Physiological workload reactions to increasing levels of task difficulty. Ergonomics 41:656–669PubMedCrossRefGoogle Scholar
  19. 19.
    Zheng B, Tien G, Atkins SM et al (2011) Surgeon’s vigilance in the operating room. Am J Surg 201:673–677PubMedCrossRefGoogle Scholar
  20. 20.
    Jiang X, Tien G, Huang D, Zheng B, Atkins SM (2012) Capturing eye blinks from video-based eye-tracking. Behav Res Methods (accepted). Paper ID: BR-Org-12-012Google Scholar
  21. 21.
    Berguer R, Smith W (2006) An ergonomic comparison of robotic and laparoscopic technique: the influence of surgeon experience and task complexity. J Surg Res 134:87–92PubMedCrossRefGoogle Scholar
  22. 22.
    Howard SK, Gaba DM (2004) Trainee fatigue: are new limits on work hours enough? CMAJ 170:975–976PubMedCrossRefGoogle Scholar
  23. 23.
    Dexter F, Epstein RH (2006) Holiday and weekend operating room on-call staffing requirements. Anesth Analg 103:1494–1498PubMedCrossRefGoogle Scholar
  24. 24.
    Zheng B, Rieder E, Cassera MA et al (2012) Quantifying mental workloads of surgeons performing natural orifice transluminal endoscopic surgery (NOTES) procedures. Surg Endosc. doi: 10.1007/s00464-011-2038-x

Copyright information

© Springer Science+Business Media, LLC 2012

Authors and Affiliations

  • Bin Zheng
    • 1
  • Xianta Jiang
    • 2
  • Geoffrey Tien
    • 2
  • Adam Meneghetti
    • 3
  • O. Neely M. Panton
    • 3
  • M. Stella Atkins
    • 2
  1. 1.Department of Surgery, 3-002F Li Ka Shing Centre for Health Research InnovationUniversity of AlbertaEdmontonCanada
  2. 2.Computing ScienceSimon Fraser UniversityBurnabyCanada
  3. 3.Department of SurgeryUniversity of British ColumbiaVancouverCanada

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