Fernando J Kim, MD, David E Sehrt, BS, Shalini Tayal, MD, Wilson R Molina, MD. Denver Health Medical Center, Tony Grampsas Cancer Center, University of Colorado Health Sciences Center
Introduction:To quantify the amount of obstruction by surgical plume generated from the first generation cordless and traditional ultrasonic harmonic scalpels (HS) on laparoscopic visibility and to examine the temperature profile for each instrument during activation and histological analysis.
Materials and Procedures:The Sonicision (cordless), Harmonic Ace, and SonoSurg were applied to bovine liver ex vivo on the industry specified minimum (min.-coagulation) and maximum (max.-cut) settings. Real time surgical plume formation was captured digitally after instrument activation. Images were recorded and analyzed using the ImageJ software via a laparoscope positioned in a laparoscopic trainer. The percentage of pixels containing plume in each video frame was measured and analyzed. Similarly, the FLIR infrared camera captured the activation temperature only generated by the instruments on both settings after control emissivity measurements were consistent with titanium (ε=0.400). Histological analysis of the tissue after activation was examined by Pathologist for a blinded analysis. Data is presented as Average ± Confidence Interval. Statistical difference was considered for p<0.05.
Results: During 3 seconds of min activation, average plume formations in all instruments were statistically different and the lowest was the Sonosurg. During 2 seconds of max activation, the average plume formation was highest with Ace compared to other devices (Table 1). Temperature was measured after calibration and revealed that Ace had the highest temp during min activation and Sonicision obtained the highest during max (Table 2). Histological analysis of tissue confirmed activation of the devices determined by coagulative necrosis at the edges, cautery effect, and inflammatory reaction compared to normal tissue.
Table 1. Maximum Plume Formation
|Min Setting||*4.80 ± 1.76||*26.63 ± 7.56||*0.21 ± 0.16||<0.001|
|Max Setting||8.76 ± 2.60||*12.65 ± 2.07||9.46 ± 2.58||0.020|
Table 2. Maximum Temperature
|Emissivity (Titanium Control)||0.401 ± 0.012||0.488 ± 0.037||0.394 ± 0.040|
|Min Setting||172.09 ± 22.11||190.00 ± 13.83||*111.19 ± 11.79||<0.001|
|Max Setting||*225.01 ± 9.61||194.24 ± 19.63||213.20 ± 10.10||0.020|
Conclusion: Surgical plume can accurately be measured by digital image capturing real-time during laparoscopic US devices activation in the pelvic laparoscopic trainer. Temperature < 110°C produced minimal surgical plume formation while temperatures > 110°C produced greater amounts of plume and may interfere with surgical field visualization and increase time of surgery and efficiency. Variations of surgical plume formation and temperature generation by different laparoscopic devices, including the first generation cordless HS, may be attributed to device specifications such as blade shape, blade displacement, operating frequency, and clamping strength. The devices studied exhibited different degrees of plume production according to their maximum and coagulation settings.
Session Number: SS02 – Instrumentation / Ergonomics
Program Number: S007