Performance and microbiological safety testing after multiple use cycles and hydrogen peroxide sterilization of a 5-mm vessel-sealing device

Incidence of residual biologic debris and contamination of reused bipolar vessel sealing devices after ethylene oxide sterilization following splenectomy

OBJECTIVE

The aim of the present study was to quantify the amount of biologic debris present within disposable bipolar vessel sealing devices after each use for canine splenectomies and determine the aerobic bacterial load of the debris following instrument resterilization with ethylene oxide.

STUDY DESIGN

Prospective observational clinical study.

STUDY POPULATION

Client-owned dogs (n = 40) presenting to a single specialty hospital for open, routine, or emergency splenectomies.

METHODS

A total of 16 bipolar vessel sealing devices were randomly assigned to undergo one, two, three, or four splenectomies, manual hand cleanings, and ethylene oxide sterilizations before being dismantled. After final use and sterilization, each handset was agitated in phosphate-buffered saline before disassembly, which was submitted for aerobic culture. Following aseptic disassembly, all biological residue was photo-documented, collected, quantified using a subjective scoring system, and submitted for culture.

RESULTS

Biologic debris was present within the inner mechanics of all devices, specifically under the blade used for vessel transection. A linear increase in debris was not appreciated amongst devices used once versus devices used multiple times. None of the devices nor any of the biologic debris cultured positive following sterilization with ethylene oxide.

CONCLUSION

The presence of biologic debris was documented after the initial use of disposable bipolar vessel sealing devices, but no devices or debris yielded positive culture results following ethylene oxide sterilization after splenectomies.

CLINICAL SIGNIFICANCE

Increased risk of iatrogenic surgical site contamination from reused vessel sealing devices is unlikely when they have been cleaned and sterilized with ethylene oxide after up to four splenectomy surgeries.

Augmenting Veterinary Minimally Invasive Surgery: Evidence-based Review of Foundational and Novel Devices and Technology

Veterinary minimally invasive surgery continues to grow as a specialty. With increasing experience in this field, comes improved accessibility as well as progressive complexity of procedures performed. Advancement in technology has been both a response to the growth and a necessary driver of continued refinement of this field. Innovative research leading to advancements in surgical equipment has led to the development of novel image acquisition platforms, cannulas, smoke evacuation systems, antifog devices, instrumentation, and ligating/hemostatic devices. These innovations will be reviewed and potential clinical applications are discussed.

Comparison of two advanced bipolar tissue sealer/dividers for laparoscopic ovariectomy in dogs: articulating enseal G2 versus Ligasure Maryland device

BACKGROUND

Advanced bipolar tissue sealer/dividers provide the most reliable and efficient means of tissue dissection and blood vessel sealing in laparoscopic surgery and the techniques are continuously improved. In veterinary practice, cost-effectiveness is of major impact, leading to re-use of instruments designed and sold for single use. Two high-end devices were evaluated and compared in a highly standardized laparoscopic ovariectomy procedure in dogs: The new generation Ligasure Maryland Sealer/Divider (LMSD) with improved atraumatic curved jaw shape for delicate tissue handling and dissection and non-stick nanocoating, and the new-generation Articulating Enseal G2 (AENG2) with several proclaimed features improving surgical performance, including articulation of the forceps tip; improved tissue compression during sealing; unique offset electrode configuration; and specific nanoparticle coating minimizing thermal spread and tissue sticking. Twenty-one client-owned dogs admitted for elective laparoscopic ovariectomy were randomly assigned to one of two groups: ovariectomy using AENG2 on the left ovary and LMSD in the right ovary or vice-versa. Procedural video recordings were used to assess ovarian ligament fat score, smoke formation, occurrence of bleeding, and excision duration. Excised tissues were examined histopathologically and collateral thermal damage was scored in three anatomic zones: suspensory ligament, vascular pedicle, and uterine junction. Tissue sealers were used repeatedly following standardized cleaning protocol with instrument washing machine and ethylene oxide gas sterilization and the number of uses until device failure was recorded.

RESULTS

Excision times were significantly increased for AENG2 (median 01:35 min) compared to LMSD (median 01:00 min). Minor hemorrhage from incomplete sealing occurred in 3 sites in 2 patients (2x AENG2, 1x LMSD) and was not significantly different between groups. Smoke production as scored on videos and thermal tissue damage scores on histopathology also did not differ between AENG2 and LMSD. Both vessel sealers could be re-used repeatedly.

CONCLUSION

AENG2 provides a good alternative to LMSD in laparoscopic ovariectomy, with only minor differences in measured variables. Subjectively, the articulating feature of AENG2 did not improve surgical performance in laparoscopic ovariectomy and the use of LMSD appeared more straight-forward for this specific procedure. However, differences in operating these devices may be subject to personal preference.

3D printed cannulas for use in laparoscopic surgery in feline patients: A cadaveric study and case series

OBJECTIVE

To evaluate custom 3D printed laparoscopic cannulas (3DPC) in a feline cadaveric abdominal surgery model and report their use in two live feline subjects.

STUDY DESIGN

Experimental cadaver study, live subject case series.

ANIMALS

Ten feline cadavers; two feline subjects.

METHODS

Custom 3DPCs were initially modeled in a PLA filament material and then created in an autoclavable dental resin for use in live patients. The surgery time, number of surgical collisions and cannula complications were recorded during cadaver procedures before and after use of 3DPCs. Cannula complications were recorded during live procedures and patients were followed to suture removal to record any incisional complications.

RESULTS

There was a significant reduction in mean surgical time (125.6 vs. 95.2 min, p = 0.03), mean number of instrument collisions (6.8 vs. 2.6, p = 0.03), and mean number of cannula complications (10 vs. 2.2, p = 0.03) with the use of only 3DPCs during the procedure. During the live procedures the use of the 3DPCs was successful and no postoperative complications occurred at the incision sites.

CONCLUSION

The use of customized 3DPCs may improve surgical dexterity and decrease complications in advanced procedures and was not associated with any clinical complications in two cats. The use of 3DPCs in veterinary medicine may allow for wider practice of laparoscopic techniques in small animals.

Comparison of conventional ligatures and a vessel sealing device for haemostasis during open ovariohysterectomy in rabbits

AIMS

To compare surgical times and rates of intra-operative and post-operative complications for open ovariohysterectomy (OVH) in female rabbits using conventional ligatures or a vessel sealing device (VSD) for haemostasis.

METHODS

Female pet rabbits (n = 23) presented for OVH for either desexing or treatment of reproductive disorders were randomly assigned to a conventional ligatures (CL) group (n = 12) or a LigaSure 5-mm (LS5) group (n = 11). In the CL group, the ovarian pedicles were ligated with a single surgeon's knot. After transection of the ovarian pedicles, the broad ligament was manually broken down along the uterine horns to their respective cervices. In the LS5 group, both ovarian pedicles and the broad ligaments were sealed with a LigaSure Dolphin Tip VSD with 5-mm forceps. All the rabbits were hospitalised for 24 hours after surgery. Two weeks after discharge, a clinical recheck examination was performed. Incision length, overall surgical time (from initial incision to completion of intradermal suturing), OVH time (from identification of the first ovary to transection of the vaginal vault), and intra- and post-operative complications were recorded and compared between groups, using the Student's t-test for normally distributed continuous data, the Wilcoxon-Mann-Whitney test for non-normally distributed continuous data and Pearson's χ2 test for categorical data.

RESULTS

The mean overall surgical time was 14.1 (SD 4.4) minutes. The surgery took 15.0 (SD 4.9) minutes in the CL group and 13.1 (SD 3.8) minutes in the LS5 group (p=0.10). The OVH time was shorter in the LS5 group (mean 4.2 (SD 0.9) minutes) than in the CL group (mean 6.3 (SD 1.7) minutes; p = 0.005). No intra-operative complications were encountered in the LS5 group. Haemorrhage occurred in three rabbits in the CL group. One rabbit in the LS5 group developed steatonecrosis post-operatively. There was no evidence of a difference in the proportion of rabbits that experienced intra- and post-operative complications (p = 0.25 and p = 0.94 respectively) between groups.

CONCLUSIONS

The use of a LigaSure 5-mm VSD and conventional ligatures during open OVH were both associated with similar overall surgical times and complication rates. The OVH times were shorter in the LS5 group compared to the CL group.

CLINICAL RELEVANCE

Use of the LigaSure 5-mm VSD allows efficient haemostasis while performing open OVH in female pet rabbits.

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.

Pet-owner perceptions of laparoscopy in an urban hybrid veterinary practice

OBJECTIVE

To investigate owner perceptions of laparoscopic surgery, including attitudes towards paying more for minimally invasive surgery (MIS).

STUDY DESIGN

Randomized cross-sectional prospective survey.

SAMPLE POPULATION

One hundred owners presenting at a combined general and specialty practice.

METHODS

Participants were interviewed using a survey tool to assess prior knowledge of laparoscopic procedures, attitude for or against these procedures, reasons for this attitude, and whether they would pay more for these procedures. Demographic data were collected.

RESULTS

Fifty-five percent of owners had previous knowledge of laparoscopy. Ninety-two percent of owners would choose laparoscopy over an open procedure for their pet. Reasons given for preferring laparoscopy: less postoperative pain (66.3%), shorter length of hospitalization (26.1%), better cosmesis (20.1%), perception of lower cost (15.2%), faster return to function (14.1%), length of anesthesia (5.4%), and other reasons (26.1%). Ninety-one percent of owners were willing to pay more for MIS. Among owners who indicated they would be willing to pay more, owners presenting with dogs were 2.5 times more likely to be willing to pay at least $1000 more than owners presenting with cats.

CONCLUSION

The majority of owners surveyed at a large hybrid hospital in an urban setting choose laparoscopic over open procedures and are willing to pay more for them.

CLINICAL SIGNIFICANCE

The results highlight the importance of client and veterinarian education regarding the options of MIS for pets, as owners who are informed may prefer referral for these procedures. The financial investment to build a MIS practice may be justified.

Comparison between intracorporeal and extracorporeal ligations in a laparoscopic ovariectomy model in dogs

OBJECTIVE

To compare the influence of extracorporeal and intracorporeal ligations on the duration of and complications associated with laparoscopic ovariectomy in dogs.

STUDY DESIGN

Prospective randomized experimental study.

ANIMALS

Healthy intact female dogs (n = 18).

METHODS

The left and right ovarian pedicles of dogs undergoing laparoscopic ovariectomy were randomly assigned to intracorporeal (n = 18) or extracorporeal (n = 18) ligation groups. Surgeries were performed by two American College of Veterinary Surgeons (ACVS) diplomates and two ACVS residents. The time required to place extracorporeal and intracorporeal ligations, duration of surgery, and intraoperative complications were compared between ligation techniques. Postoperative complications were recorded.

RESULTS

The time required for intracorporeal ligation (17.3 ± 8.7 minutes) did not differ from that required for extracorporeal ligation (15.1 ± 6.1 minutes; P = .38). The total duration of surgery was 102.7 ± 28.7 minutes including portal placement and veterinary student closure of incisions. Ligation of the ovarian pedicle was successful in 16 of 17 dogs. Intraoperative hemorrhage occurred in three dogs, and postoperative complications were noted in three dogs, without apparent difference between ligation techniques.

CONCLUSION

No difference was identified between extracorporeal and intracorporeal ligations of ovarian pedicles.

CLINICAL SIGNIFICANCE

This study does not provide evidence to support one ligation technique rather than the other.

Ex vivo comparison of sliding knot ligatures vs. haemostatic clips for equine small intestinal mesenteric vessel occlusion

BACKGROUND

In equine abdominal surgery, resection and anastomosis of strangulated intestine is a commonly performed procedure. To date, ligatures, vessel sealing devices and the ligate-divide stapler have been described for this use in horses. The objective of this study was to compare the application of haemostatic clips and ligatures to occlude equine mesenteric vessels. Portions of jejunum with ten associated mesenteric vessels were collected from 12 horses at a local abattoir and divided into two groups. Portions of intestine were divided into two sections comprising five vessels each and assigned to Group A or Group B. Each vessel was occluded with a triple ligature. In Group A, vessels were ligated with three circumferential ligatures tied with a sliding knot with two overthrows. In Group B, vessels were occluded with application of three haemoclips. The procedures were performed by the same experienced surgeon. Intestinal length, construction time and vessel leaking pressure were measured and compared between groups.

RESULTS

The intestinal length (mean ± SD) was 3.78 ± 0.43 m in Group A and 3.04 ± 0.83 m in Group B. The difference was not significant (p = 0.297). The construction time (mean ± SD) was 7.03 ± 0.34 min in Group A and 2.40 ± 0.43 min in Group B. The difference was significant (p < 0.0001). The leaking pressure was 1000 (750-1050) mmHg (median, IQ range) in Group A and 1050 (800-1050) mmHg (median, IQ range) in Group B. The difference was not significant (p = 0.225).

CONCLUSIONS

Haemoclip application is comparable in terms of leaking pressure but quicker than sliding knots to apply.

Evaluation of the performance of an endoscopic 3-mm electrothermal bipolar vessel sealing device intended for single use after multiple use-and-resterilization cycles

OBJECTIVE

To evaluate the performance of an endoscopic 3-mm electrothermal bipolar vessel sealing device (EBVS) intended for single use after multiple use-and-resterilization cycles.

STUDY DESIGN

Ex vivo study.

SAMPLE POPULATION

Eight 3-mm EBVS handpieces.

METHODS

Handpieces were subjected to a maximum of 15 cycles of testing, including simulated surgery, sealing and burst pressure testing of porcine carotid arteries, reprocessing, and hydrogen peroxide plasma resterilization. Failure was defined as two sequential vascular seal leakage events occurring at <250 mm Hg. Histological evaluation, maximum external temperature of the jaws, sealing time, tissue adherence, jaw surface characterization, and mechanical deterioration were studied. Failure rate was analyzed by using a Kaplan-Meier curve. Linear and ordinal logistic mixed models were used to analyze sealing time, handpiece jaw temperature, and adherence score.

RESULTS

Mean ± SD diameter of arteries was 3.22 ± 0.35 mm. Failure was observed starting at cycle 10 and going up to cycle 13 in 37.5% (3/8) of the handpieces. Tissue adherence increased after each cycle (P < .001). Maximum external temperature (79.8°C ± 13.9°C) and sealing time (1.8 ± 0.5 seconds) were not significantly different throughout cycles up to failure. A flatter surface and large scratches were observed microscopically throughout the jaw surface after repeated use and resterilization.

CONCLUSION

The 3-mm EBVS handpiece evaluated in this study can be considered safe to use for up to nine reuse-and-resterilization cycles.

CLINICAL SIGNIFICANCE

These data provide the basis for establishing preliminary guidelines for the reuse and hydrogen peroxide plasma resterilization of an endoscopic 3-mm EBVS handpiece.

Partial cystectomy with a bipolar sealing device in seven dogs with naturally occurring bladder tumors

OBJECTIVE

To describe the use of a bipolar sealing device (BSD) for partial cystectomy in dogs undergoing excision of bladder tumors.

STUDY DESIGN

Multicenter, prospective, clinical pilot study.

SAMPLE POPULATION

Seven client-owned dogs with nontrigonal urinary bladder lesions.

METHODS

Dogs underwent a sealed partial cystectomy with a BSD, with or without cystoscopic guidance of the resection. The sealed cystectomy site was oversewn with a single-layer simple continuous pattern with monofilament absorbable suture.

RESULTS

Sealed partial cystectomy was successfully performed in all dogs, with a median surgical duration of 69 minutes (range, 50-120). Lesions were located at the apex in six dogs and on the ventral midbody of the bladder in one dog. No urine leakage from the BSD luminal seal was visible prior to suture closure in three dogs, while varying amounts of urine leaked from the sealed site in four dogs. Suture was placed over the seal in grossly normal bladder tissue in six dogs and in the BSD peripheral thermal effect zone in one dog; in this latter dog, revision cystorrhaphy was required 3 days later because of uroabdomen. The other six dogs had no clinical evidence of urinary bladder healing complications.

CONCLUSION

The integrity of the seal generated by the BSD tested here on partial cystectomies varied between dogs and was unpredictable.

CLINICAL SIGNIFICANCE

Sealed partial cystectomy with a BSD may reduce exposure of urinary bladder luminal contents to the surgical site. However, the placement of sutures over the seal and through grossly normal bladder tissue is recommended to prevent postoperative uroabdomen.

Effect of multiple use and sterilization on sealing performance of bipolar vessel sealing devices

Background

Advanced bipolar vessel sealing devices are widely used in human and veterinary medicine to reduce the operation time and intraoperative blood loss. Because most devices are made for a single use, their application is cost intensive. The aim of this study was to investigate the influence of multiple uses and sterilization on the performance of bipolar vessel sealing devices.

Methods

The burst pressure of sealed porcine renal arteries was compared between the disposable devices „LigaSure”(Valleylab) and „Caiman“(Braun Vetcare) and the reuseable device „MarSeal”(KLS Martin). Additionally, the influence of the sterilization process was investigated, and the sealing time, number of cutting activations and tissue sticking were noted.

Results

The disposable devices showed reliable performances over multiple activations and sterilization cycles, except for one Caiman device. Seals created with all devices achieved supra-physiologic burst pressures, with the highest pressure measured in a cycle using a MarSeal device.

Discussion

During 25 activations with and without intermittent sterilization, no correlation was found between increasing seal numbers and decreasing burst pressure. However, the number of cycles in our study was limited to five.

Conclusion

For limited numbers of cycles and sterilization procedures, seals created with the disposable vessel sealing devices LigaSure and Caiman achieved burst pressures comparaable to those produced with the reuseable MarSeal.