Jacobs Stephan, Holzhey David, Kiaii Bob B, Onnasch Joerg F, Walther Thomas, Mohr Friedrich W, Falk Volkmar
Department of Cardiac Surgery, Heartcenter, University of Leipzig, Leipzig, Germany.
Ann Thorac Surg. 2003 Dec;76(6):2029-35; discussion 2035-6. doi: 10.1016/s0003-4975(03)01058-0.
Surgical performance is limited by human factors. Beating-heart surgery requires full dexterity and motion tracking. Currently techniques for total endoscopic beating-heart bypass grafting using telemanipulation systems are being developed. The aim of this study was to assess the limitations for manual and telemanipulator-assisted motion tracking using the da Vinci telemanipulator system.
To simulate beating-heart conditions an endoscopic trainer was developed. Twenty subjects were asked to touch targets manually and with telemanipulator assistance with different patterns of increasing index of difficulty (resting model, unstabilized, and stabilized model with a frequency of 35, 60, and 90 beats per minute). In addition one task was performed using different scaling ratios on a resting model. The times between hits as well as errors were electronically recorded.
There was no significant impact of various frequencies and amplitudes for manual tracking. The average values for the delay (k(m)[ms]) and information-processing (c(m) [ms/bit]) constants for the manual tasks were 201 ms and 86 ms/bit respectively. Both the delay constant (k(t) = 630 ms; p < 0.0005) and the information-processing constant (c(t) = 250 ms/bit; p < 0.0005) were increased for the telemanipulator-assisted tasks at rest. When working on moving targets telemanipulator-assisted tracking required significantly more time and led to more errors. At a frequency of 90 beats per minute telemanipulator-assisted tracking became more difficult.
Endoscopic beating-heart bypass grafting requires optimal stabilization to avoid inaccuracies due to incomplete motion tracking. At higher frequencies telemanipulator-assisted tracking became more difficult, demonstrating the technical limits of current telemanipulator technology.
手术操作受人为因素限制。心脏不停跳手术需要充分的灵活性和运动追踪。目前正在开发使用远程操作手术系统进行全内镜心脏不停跳搭桥术的技术。本研究的目的是评估使用达芬奇远程操作手术系统进行手动和远程操作辅助运动追踪的局限性。
为模拟心脏不停跳的情况，开发了一种内镜训练器。20名受试者被要求在不同难度增加模式下（静止模型、不稳定模型和频率为每分钟35、60和90次心跳的稳定模型）手动及在远程操作辅助下触摸目标。此外，在静止模型上使用不同缩放比例执行一项任务。击中目标的时间间隔以及错误均通过电子方式记录。
各种频率和幅度对手动追踪无显著影响。手动任务的延迟（k(m)[毫秒]）和信息处理（c(m)[毫秒/比特]）常数的平均值分别为201毫秒和86毫秒/比特。在静止状态下，远程操作辅助任务的延迟常数（k(t)=630毫秒；p<0.0005）和信息处理常数（c(t)=250毫秒/比特；p<0.0005）均增加。在处理移动目标时，远程操作辅助追踪需要显著更多时间且导致更多错误。在每分钟90次心跳的频率下，远程操作辅助追踪变得更加困难。
内镜心脏不停跳搭桥术需要最佳的稳定状态，以避免因运动追踪不完整而导致的不准确。在较高频率下，远程操作辅助追踪变得更加困难，这表明了当前远程操作手术技术的技术局限性。
