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Tissue Fusion Device
ОглавлениеTissue fusion technology, or vessel sealant devices, are bipolar electrosurgery devices that rely on tissue fusion for control of blood vessels and lymphatics. These devices measure tissue impedance and subsequently deliver the appropriate the amount of energy to achieve a safe seal. Vessel sealant devices have been approved for sealing vessels up to 7 mm in diameter [15–17].
This system uses low voltage with high current. The generator senses tissue impedance (electrical resistance) and adjusts the energy to achieve hemostasis while minimizing heat and tissue carbonization (Figure 5.8). An acoustic signal is delivered to indicate that the sealing cycle has been completed. This system denatures elastin and collagen, and the strength of the seal is dependent on the ratio of elastin and collagen within the tissues [18]. The handpiece applies a certain amount of pressure on the tissue to fuse. This amount of pressure is characteristic of the device used. Vessel sealant devices can achieve hemostasis without dissection of the blood vessels. This is particularly valuable when blood vessels are surrounded by fat or other tissues (e.g., an ovarian pedicle). A 5‐mm handpiece can also be used for blunt tissue dissection.
Figure 5.8 Valley Lab Force Triad generator, which combines monopolar, bipolar, and vessel sealant technology. It features three touchscreen modules. Handpieces are automatically recognized when they are plugged in.
Source: From Huhn [3].
Bipolar vessel sealant devices have been used in several organ systems, including the reproductive tract, lung, liver, and other soft tissue structures [19–22]. There are numerous generators and handpieces available for use in open surgery and MIS (Figure 5.9). Lateral thermal damage has been reported to occur between 1.5 and 6 mm from the coagulation site [13, 14, 23]. Bipolar vessel sealant technology has proven to be safe and effective for use in MIS with applications in numerous procedures, including reproductive surgery, adrenalectomy, splenectomy, nephrectomy, partial pancreatectomy, and pericardiectomy. The resulting blood vessel seals have been tested to withstand pressure well above physiologic systolic pressures [17,24–28]. Although peripheral lung biopsies have been successfully obtained in experimental studies [19], the variability of bronchus sealing makes this technique unreliable for larger biopsies [29, 30].
Figure 5.9 Valley Lab LigaSure generator with numerous bipolar handpieces for open and minimally invasive surgery. Some handpieces require foot‐pedal activation; others are handswitch activated.
Source: From Huhn [3].
Figure 5.10 A variety of bipolar handpieces are available for open and MIS. A cordless ultrasonic device is also available for use in MIS.
Source: Courtesy of Medtronic, Minneapolis, MN.
Vessel sealant device handpieces are compatible with specific generators and vary in terms of shaft length, shaft diameter (3–12 mm), and function. Commonly used LigaSure (Covidien, Medtronic, Minneapolis, MN, USA) handpieces in MIS include the Atlas, Maryland, and Dolphin Tip (Figure 5.10). The Maryland and Dolphin Tip are finer and can be used for blunt dissection in addition to vessel sealing. The LigaSure Advance and LigaSure Retractable L‐hook handpieces combine a monopolar tip with vessel sealant technology. The Caiman (Aesculap, Tuttlingen, Germany) handpieces are available in 5 and 12 mm diameters in both straight and articulating options (up to 80°). A finely curved Maryland tip is also available for tissue dissection. Enseal (Ethicon, Johnson&Johnson, Cincinnati, Ohio, USA) is also available in a variety of curved, straight, and articulating handpieces. MarSeal (KLS Martin, Tuttlingen, Germany) is designed as a reusable vessel sealant device handpiece. Similar to the other single‐use vessel sealant devices, they offer curved and straight tipped handpieces. JustRightTM from Bolder Surgical (Louisville, CO, USA) developed a 3 mm Vessel Sealer for use in human pediatrics, which seals vessels up to 5 mm in diameter and has a Maryland style tip for dissection.
Although most vessel sealant device handpieces are designed for single use only, resterilization in veterinary medicine is common. Reuse and resterilization of vessel sealant devices intended for single‐use raises the questions of the effectiveness of sterility and ability to perform safe and effective seals. Kuvaldina et al. [27] evaluated the number of uses, cleaning, and resterilization cycles with low temperature hydrogen peroxide sterilization for two LigaSure handpieces intended for open surgery. Based on the rate of vascular seal failure, they recommend discarding the Small Jaw handpiece after 9 cycles and the Impact handpiece after 16 cycles. Another study found the LigaSure Atlas handpiece formed an effective seal after 15 uses and resterilization cycles with ethylene oxide [26]. Gardeweg et al. [25] compared the reuse and resterilization of LigaSure, Caiman, and marSeal handpieces with a low temperature steaming process with formaldehyde as an active agent and found that LigaSure, Caiman, and marSeal devices all performed reliable seals after multiple uses and sterilizations except for one Caiman handpiece. Five cycles of sterilization were performed in this study. Performance and microbiological safety of the LigaSure 5 mm Maryland handpiece were evaluated after multiple uses and resterilization cycles by Valenzano et al. [31] Eleven of 12 handpieces failed to activate when the jaws were closed, and the activation button was depressed after a mean of 7.7 cycles. In this study, each handpiece was initially washed in tap water and a 2% enzymatic cleaner solution. The jaws of the instrument were soaked in the 2% enzymatic cleaner solution for five minutes and then scrubbed with a sponge and metal brush and air‐dried. The handpiece was pouch packaged and sterilized with a low‐temperature hydrogen peroxide sterilization unit. Using this protocol for cleaning and sterilization, no handpieces had positive cultures [31]. The 3‐mm JustRightTM vessel sealant device from Bolder Surgical was evaluated for multiple uses and resterilization cycles and was considered safe for use for up to nine reuse and resterilization cycles [32].
Table 5.2 Various energy devices and their capabilities.
| Energy device (manufacturer) | Monopolar | Bipolar | Tissue sealing | Ultrasonic dissector |
|---|---|---|---|---|
| Force triad (Valley Lab, Boulder, CO) | ✓ | ✓ | ✓ | |
| Ethicon Gen11 generator (Ethicon, Cincinnati, OH) | ✓ | ✓ | ||
| Sonicision (Covidien, North Haven, CT) | ✓ | |||
| Altrus (Conmed, Utica NY) | ✓ | |||
| Ultracision (Ethicon, Cincinnati, OH) | ✓ | |||
| Autosonix (Covidien North Haven, CT) | ✓ | |||
| Thunderbeat (Olympus, Center Valley, PA) | ✓ | ✓ | ||
| JustRightTM JR 100 (Bolder Surgical Louisville, CO) | ✓ | |||
| Caiman Lektrafuse RF generator (Aesculap, Tuttlingen, Germany) | ✓ |
