Usefulness of electrosurgical techniques in thyroid gland surgery

Incidence of and risk factors for surgical site infection following canine limb amputation

OBJECTIVE

To determine the incidence of and risk factors for surgical site infection (SSI) following canine thoracic and pelvic limb amputations.

STUDY DESIGN

Retrospective, multicenter study.

ANIMALS

Dogs (n = 248).

METHODS

Medical records were reviewed for preoperative, intraoperative, and postoperative variables including indication for amputation, amputation type, method of muscle transection, duration of surgery and anesthesia, and wound classification. Follow up was ≥30 days or until SSI development. Logistic regression and Fisher's exact tests were used to compare SSI incidence to variables of interest.

RESULTS

The incidence of SSI was 12.5% for all procedures and 10.9% for clean procedures. Factors increasing odds of SSI were muscle transection with a bipolar vessel sealing device (P = .023 for all procedures, P = .025 for clean procedures), procedure classified as other than clean (P = .003), and indication for amputation of bacterial infection (P = .041) or traumatic injury (P = .003) compared to neoplasia.

CONCLUSION

Use of bipolar vessel sealing devices for muscle transection increased the odds of developing an SSI whereas use of electrosurgery and/or sharp transection did not. Dogs with surgical sites that were other than clean, or with bacterial infection and/or traumatic injury were also at increased odds of SSI.

CLINICAL SIGNIFICANCE

Use of electrosurgery or sharp transection for muscle transection should be considered rather than use of bipolar vessel sealing devices to decrease odds of SSI in dogs undergoing limb amputation. Further studies across a variety of procedures are needed to validate these findings given the increasing popularity of these devices in veterinary medicine.

More compression improves sealing effect on larger pulmonary arteries

BACKGROUND

Small arteries and veins up to 7 mm can be sealed safe and divided with a bipolar sealing instrument. The results for the safe sealing of larger vessels were unsatisfactory in the past. Using an ex vivo pulmonary artery model, we aimed to investigate, if a higher compression force and duration will improve the bursting pressures in case of vessels >7 mm.

MATERIAL AND METHODS

Heart-lung preparations (from 90 kg pigs) were removed en bloc at a slaughterhouse. The whole pulmonary artery was exposed from the pulmonary valve up to the periphery of the left lung. In the laboratory, a digital pressure sensor was implanted in the central end of the blood vessel to measure the bursting pressure (in mbar). The vessels examined were divided into three groups by diameter: 1-6 mm, 7-12 mm and >12 mm. After bipolar sealing, bursting pressures were determined by pneumatic testing. Seals were made using three equal MARSEAL instruments (Gebrüder Martin GmbH & CoKG, Tuttlingen, Germany) with a SealSafe G3 electric current and different jaw compression forces of each 35 N, 45 N, and 55 N. Bursting pressures were also measured for different compression durations (0 s, 5 s, 10 s, and 20 s) with 35 N compression. Mean bursting pressures were calculated for each group (n = 15). Groups were compared using a nonparametric test (Mann-Whitney U test). The significance level was P < 0.05.

RESULTS

Mean bursting pressures in the 1-6 mm blood vessels were 290.5 ± 77.1 mbar (35 N), 323.0 ± 76.0 mbar (45 N) and 301.6 ± 69.9 mbar (55 N). The groups did not differ significantly. Mean bursting pressures in the 7-12 mm vessels were 108.1 ± 19.1 mbar (35 N), 154.3 ± 28.5 mbar (45 N), and 212.4 ± 45.3 mbar (55 N). In blood vessels >12 mm in diameter, we found mean bursting pressures of 77.7 ± 11.7 mbar (35 N), 117.6 ± 27.1 mbar (45 N), and 166.3 ± 56.6 mbar (55 N). The results for the groups with 55 N compression were significantly higher than for the other groups. A compression duration of 5 s led to significantly higher mean bursting pressures than a duration of 0 s but a duration of >5 s did not bring a further significant increase in mean bursting pressure. Histologic staining of the seal zone and microscopic examination did not reveal any differences relating to compression force.

CONCLUSIONS

With a higher compression force, we reached satisfactory bursting pressures in case of pulmonary arteries >7 mm. An additional 5 s of compression before starting coagulation brings a further significant increase in bursting pressure. However, there is no advantage in a longer compression.

A multicenter, randomized, controlled clinical trial of LigaSure small jaw vessel sealing system versus conventional technique in thyroidectomy

The objective of this work was to compare efficacy and adverse effects between vessel sealing system thyroid lobectomy (VSSL) with the new LigaSure™ Small Jaw Instrument and conventional thyroid lobectomy (CTL). This is a multicenter, randomized and controlled study, conducted in the Department of Otolaryngology, King Chulalongkorn Memorial Hospital, Thai Red Cross Society, Faculty of Medicine, Chulalongkorn University, Bangkok and Division of Otolaryngology, Sukhothai General Hospital, Sukhothai, Thailand. Forty subjects with solitary thyroid nodule planned for thyroid lobectomy were enrolled consecutively in both centers. Intervention was randomized by block randomization into two groups (VSSL, CTL). Primary outcomes were operative time and intraoperative blood loss. Secondary outcomes were postoperative blood loss and recurrent laryngeal nerve paralysis. There was clinically significant less operative time (VSSL/CTL = 62.4 ± 15.9/83.3 ± 16.1 min, p < 0.001) and less intraoperative blood loss (VSSL/CTL = 40.5 ± 19.1/63.3 ± 22.4 mL, p = 0.001) in VSSL group compared with CTL group. There was no significant difference of postoperative blood loss (VSSL/CTL = 58.8 ± 30.6/76.0 ± 36.9 mL, p = 0.116) between both the groups. There was one case of permanent recurrent laryngeal nerve injury found in both groups. VSSL with the new LigaSure™ Small Jaw Instrument was better than conventional technique in terms of shortening operative time. It was also better in reducing intraoperative hemorrhage, but this effect did not exceed clinically significant levels. Postoperative blood loss and recurrent laryngeal nerve injury were not significantly different between both the groups.