Analysis of medical accidents in laparoscopic surgery by the Pm-SHELL model: A feasibility study

Kazuhiko Shinohara, MD, PhD. Tokyo University of Technology

Background and Objective: Analysis of medical accidents in surgery is essential for preventing similar mishaps. The SHELL model, which was created by Hawkins, has been widely used to analyze aviation and industrial accidents according to five contributing factors: Software (S), Hardware (H), Environment (E), and Liveware (person directly [L1] and indirectly [L2] concerned). Here we propose the Pm-SHELL model, an extension of the SHELL model to incorporate patient factors (P) and organizational management factors (m). The feasibility and effectiveness of the Pm-SHELL model for analyzing medical accidents in laparoscopic surgery are investigated in this study.

Material and Methods: Twenty-one cases of accidents in laparoscopic surgery in Japan that have been described in the official incident reports are analyzed by the Pm-SHELL model. Each case is analyzed according to seven contributing factors: S, H, E, L1, L2, P, and m. The contribution of each factor is scored on a five-point scale (1, minimal contribution; 5, maximal contribution).

Results: The scores (mean ± standard deviation for the seven contributing factors are as follows: P, 2.86±0.77; m, 4.48±0.91; S, 3.14±0.46; H, 2.86±1.24; E, 3.81±0.50; L1, 4.52±0.85; L2, 4.24±0.85. Human factors (L1, L2) and organizational management factors (m) are found to be the main contributing factors of medical accidents in laparoscopic surgery.

Conclusion: The Pm-SHELL model is a feasible and useful tool for quantitatively analyzing medical accidents in laparoscopic surgery and provides an intuitive understanding of multiple contributing factors.

« Return to SAGES 2016 abstract archive