Numerical Simulation and Improvement of Surgical Procedures

The medical community is highly interested in improving the surgical protocol through reducing the surgery duration. The current study develops and validates a numerical Design-Structure-Matrix (DSM) simulation model of the entire laparoscopic cholecystectomy surgery structure, including coupling (loops) and rework.

(a) Patient preparation. 1: Insufflations (A1). 2: Local anesthesia (A2). 3: Incisions (one infraumbilical plus three others) (A3). 4: Placement of trocars (A4). 5: Insert tools (e.g., grasper) posteriorly (A5).



(b) Peritoneal preparation. 1: Expose the gallbladder with grasper (A6). 2: Dissect the left side of the gallbladder with hook cautery (A7, A8, A9, broken arrows indicating the direction of Hc motion). 3: Dissect the right side of the gallbladder with hook cautery (A10, A11, A12, broken arrows indicating the direction of Hc motion). 4: Dissect the back side of the gallbladder neck with hook cautery (A13, A14, A15, A16). 5: Expose the cystic duct and cystic artery (A17, A18).



(c) Removal of gallbladder. 1: Clip the cystic duct and artery with a clipper (cystic artery not shown, located posterior to cystic duct) (A19, A20, A22, A23). 2: Cut the cystic duct and artery with hook scissors (A21, A24). 3: Separate gallbladder from liver on the left side (A25, A26, broken arrows indicating the direction of Hc motion). 4: Separate gallbladder from liver on the right side (A27, A28, broken arrows indicating the direction of Hc motion). 5: Mobilize the gallbladder (A29). 6: Clean/close (A30).

The figures above depict surgical activities involved in laparoscopic cholecystectomy. (Ad: Anesthetic drug. Ca: Cystic artery. Cd: Cystic duct. Cl: Clip. Clr: Clipper. Fo: Forceps. Ga: Gallbladder. Gr: Grasper. Hc: Hook cautery. Li: Liver. Nk: Neck. Sp: Scalpel. Sr: Scissors. Tr: Trocar.)

The surgical activities above are analyzed through numerical Design Structure Matrix simulation below, showing 5 coupled loops (indicated by ), 8 groups of conditional activities including 4 output parallel (indicated by ) and 4 input parallel (indicated by ) groups.

The model provides a framework that affords exploring the effects of alternative activities, testing redesign of the surgical procedure, and comparing different versions of surgical protocol through simulation.