International report — Having long been used for endoscopic and laproscopic surgery, the harmonic scalpel (Ethicon Endo-Surgery), also known as an ultrasonic scalpel, is gaining a following in aesthetic surgery as a useful tool for dissecting and coagulating tissue while causing less thermal damage and a less postoperative pain and drainage than the alternative, electrocautery.
The harmonic technology differs significantly from standard electrocautery in that its cutting action is produced by vibration, instead of electric current, which involves greater production of heat.
“The harmonic scalpel relies on piezoelectric stacks that convert electricity into mechanical energy, causing the tip to oscillate between 55 and 90 micrometers, side to side, at a rate of 55,500 times per second,” explains Mohan Thomas, M.D., director of the Cosmetic Surgery Institute in Mumbai, India.
Dr. Thomas, who has used the harmonic scalpel in his cosmetic surgery practice for two years, says a key advantage of the scalpel is that it causes minimal lateral tissue damage, compared to electrosurgery.
“The scalpel causes thermal damage to only 1 to 2 millimeters of adjacent tissue, and causes coagulation of hemoglobin within small vessels at the moment they are divided, resulting in hemostasis with little epidermal and dermal injury,” he says.
The device has four capabilities, which can be achieved individually or in combination: cutting, coagulation, coaptation and cavitation, and the actions are typically applied consecutively, according to Ethicon Endo-Surgery’s Web site.
As opposed to electrocautery, harmonic technology doesn’t send an electric current through the body, reducing the risk of cautery burns, Dr. Thomas explains.
“There is minimal charring of tissue and markedly reduced collateral damage to tissues when compared to regular electrocautery,” he says.
The harmonic scalpel was introduced in the United States in 1992 at a meeting of the Society of American Gastrointestinal Endoscopists after it received Food and Drug Administration (FDA) clearance for traditional surgery and laparoscopic use. Since then, Ethicon Endo-Surgery has introduced a newer line of Synergy blades designed specifically for creating skin flaps in plastic surgery.
More comfort, less drainage
Luis A. Vinas, M.D., a plastic surgeon practicing in Palm Beach, Fla., says he uses the harmonic device for everything from tummy tucks to breast reduction, and the absence of heat translates to substantially reduced discomfort following the procedure.
“In surgeries where there is a lot of dissection, such as abdominoplasties, patients often complain about a strong burning sensation and pain in the lower abdomen in the days following the procedure due to the actual burning of the electrocautery,” he says. “With the harmonic technology, however, there is no burning sensation and patients may just experience some tightening of the muscle.”
And because there is only minimal burning of fat and tissue, the formation of fluid or other aspects of healing are reduced, resulting in less drainage in breast and body procedures, he added.
“This really helps for people who want to go back to work sooner,” Dr. Vinas says. “The dissection is very clean and I will often tell patients they may be able to go back to work in as soon as five to seven days, whereas otherwise it may have taken three weeks to reach the same level of healing.”
A spokesperson for Ethicon Endo-Surgery says that the company does not have the clinical evidence to prove consistent recovery in such a short time, but its data does indicate that the harmonic technology provides a generally faster recovery time, with reductions in postoperative pain and drainage, compared to electrocautery.
The use of harmonic blades also does not cause the smoke that occurs with electrocautery, offering surgeons an improved view of the surgical site. In addition, the harmonic technology works exceptionally well in fluid.
“Since it doesn’t conduct electricity in fluid, electrocautery does not cut tissue when it is wet, but the harmonic scalpel actually works perfectly in fluid,” Dr. Vinas says.
Learning curve
Dr. Vinas, who trains surgeons in the harmonic technique, says the technology isn’t without its own risk of burning, which even the vibration can cause, but most adverse events are the result of poor training.
“There is a learning curve to this because doctors are used to electrocautery,” he says. “If you turn the machine on, for instance, and you hit the skin for a microsecond, there won’t be any burning, but if you dissect the same area over and over again, for five or 10 seconds at a time, the heat will build up from the vibration, and that’s just a matter of improper technique.”
The device sells for approximately $10,000 for the machine, and blades are an additional cost. Ethicon Endo-Surgery also provides surgeons interested in trying out the harmonic device the option of leasing. Most hospitals already have the part of the device that transfers the energy, in which cases surgeons would only need to provide the handpiece. Dr. Vinas says he charges patients an additional $270 or $280 to have their procedure performed with this scalpel.
Dr. Thomas notes that, despite the increase in cost overhead, he expects the harmonic technology to gain more users in aesthetic surgery, particularly because the cost becomes negligible in a hospital setting and the device can be useful for a variety of procedures.
“The harmonic scalpel would be appropriate for various aesthetic surgeries,” he says. “I would use it any surgery that requires open dissection and excision of tissues, such as breast reduction, tummy tucks and body lifts.”
Disclosures: Dr. Vinas discloses that he is a consultant and faculty with Ethicon Endo-Surgery. Dr. Thomas reports no relevant financial disclosures.
