The CO2 laser-assisted no-gauze spay

    By Dr. Masahiro Seki, DVM For the Education Center

    Originally Published in Veterinary Practice News, February 2013 – Download as a PDF

    At our small animal clinic we perform multiple surgeries a day. Our routine usage of Aesculight surgical CO2 laser allows for greatly simplified soft-tissue surgeries, such as femoral head osteotomy and enucleation surgery[1] and ovariohysterectomy (OHE) described in detail in this article.

    Background

    Dr Masahiro Seki, DVM, DABLS

    Dr Masahiro Seki, DVM, DABLS

    OHE is a fundamental abdominal surgery and is one of the most frequently performed soft tissue surgeries in veterinary practices today.

    The main complications of OHE, traditionally performed with a steel scalpel and electrocautery, are postoperative pain, hemorrhage, swelling and infection[2]. At our clinic we perform all OHE procedures with a CO2 surgical laser because this technique addresses all of the aforementioned complications.

    Pets undergoing CO2 laser-assisted OHE appear to feel less to no pain, and they recover and resume their usual activities faster than after the same procedure done with a scalpel and electrocautery.

    Below is a step-by-step description of the “nogauze” spay procedure performed with CO2 laser on a young female cat. We refer to this procedure as nogauze as there is no need to use gauze to manage bleeding, and we only use one or two moist gauzes as a backstop and for wiping off the “char”.

    ‘No-Gauze’ Spay

    Step 1: Initial skin incision

    The skin is incised (Figure 1) with the CO2 laser set to 20 watts in the Super Pulse mode (Figure 2) with 0.25mm focal spot size. High power Super Pulse (SP) is especially effective as it assures minimum thermal damage to adjacent tissues. High power SP mode permits a surgeon to move the laser handpiece much faster, which minimizes thermal necrosis.

    Figure 1 - Laser Initial Skin IncisionFigure 2 - Aesculight Laser Settings Figure 3 - Laser Subcutaneous Tissue Avulsion

    Step 2: Subcutaneous tissue avulsion

    After the skin is incised in high power SP mode, the subcutaneous tissue is avulsed with Metzenbaum scissors; then the scissors are inserted under the subcutaneous tissue as a backstop and a laser incision is made (Figure 3), also with 0.25 mm spot size at 20 watts SuperPulse. Note the completely blood-free surgical field.

    Figure 4 - Linea alba is located and carefully picked up with forceps Figure 5 - Incision of Abdominal Muscle Diagram

    Step 3: Abdominal muscle incision

    Linea alba is located and carefully picked up with forceps (Figure 4). The muscle tissue is pulled outward and laser beam is directed horizontally from the side so that the beam cannot pass through to the intraperitoneal organs (Figure 5) Then, a small hole is made through linea alba with 0.25mm spot size, using CO2 laser setting 20W SP (Figure 6). Next, the winged groove director is inserted along peritonea, tension to membrane is applied and a laser cut is made (0.25mm spot size, 20W SP) (Figures 7 and 8).

    Figure 6 - Abdominal Muscle Incision 1Figure 7 - Abdominal Muscle Incision 2 Figure 8 - Abdominal Muscle Incision 3

    Step 4: Cutting the suspensory ligament

    Figure 9 - Cutting The Suspensory Ligament 1Figure 10 - Cutting The Suspensory Ligament 2The suspensory ligament is cut with a CO2 laser after pulling the ovary out (Figure 9). The power setting of the laser is 8-10W CW, and the spot size is increased to 0.4-0.8 mm. The coagulation effect of the lower power density continuous wave (CW) mode on small blood vessels is more effective, and is recommended for the best hemostasis in highly vascular tissues. It is a much safer method with no bleeding, compared to the usual breaking of the ligament with the index finger.

    Step 5: Ligation and cutting of the blood vessel

    A figure-eight ligature is placed at the site. Then, using moistened gauze as a backstop, the blood vessel is cut with the laser beam (0.4-0.8 mm spot size, 8-10W CW) for coagulation (Figure 10).

    Step 6: Cutting the broad ligament

    The broad ligament is cut without ligation using 0.4- 0.8mm spot size and the lower power setting of 6-8W CW. Note the complete lack of bleeding in the absence of ligatures (Figure 11).

    Figure 11 - Cutting The Broad Ligament Figure 12 - Cutting The Uterine Body

    Step 7: Do the other ovary the same way

    Step 8: Cutting the uterine body

    Ligation is done with a modified Miller’s knot (Figure 12) and the uterine body is cut off using 0.4-0.8mm spot size and 8-10W CW setting of the CO2 laser (Figure 13). Laser energy is applied to the uterine stump to contract and sterilize.

    Step 9: Closure

    Figure 13 - Closure Figure 14 - Post Op

    The abdominal walls are closed and the skin is sutured (Figure 14); wiping skin margins with moist Gauze sometimes is desirable if char traces are present. Stainless suture wire or skin stapler is used for suturing because they do not cause foreign body reaction and the animal doesn’t want to lick the wound. Another advantage of suture wire is that it retains its oval loop shape which helps to avoid over-restriction of the skin. It makes the wound site heal beautifully.

    Summary

    A CO2 laser assisted no-gauze spay is performed much faster than the conventional OHE procedure, and without the risk of post-operative complications and bleeding, allowing us to avoid post-surgery hospitalization. It is much appreciated by the pet owners and clinical personnel alike.

    References

    1. Seki, Masahiro. “Introducing Veterinary CO2 Laser Surgery in Japan.” Veterinary Practice News, Oct. 2012, p. 24.
    2. Welch Fossum Theresa, et al. Small Animal Surgery. 3rd ed, St. Louis: Mosby, 2007, p.726.

    Dr. Masahiro Seki is the owner of a small animal clinic Animal Laser Center in Nagoya, Japan. He is the first board-certified veterinary laser surgeon in Japan. Dr. Seki is a diplomate of the American Board of Laser Surgery, and a director at the Japanese Laser Veterinary Science Society

    This Education Center article was underwritten by Aesculight of Bothell, Wash., manufacturer of the only American-made surgical veterinary CO2 laser