Perioperative characteristics and long-term outcomes following prophylactic total laparoscopic gastropexy using a novel knotless tissue control device in 44 dogs

Abstract

Objective

To report on operative technique and outcomes following prophylactic total laparoscopic gastropexy (PTLG) using a novel knotless tissue control device (KTCD) in dogs.

Animals

This study included 44 dogs.

Procedure

Medical records were reviewed, and perioperative data were collected. Right-sided incisional gastropexy was performed using 2 strands of KTCD introduced through a 12-millimeter cannula in a single-incision multi-channeled port. Dog owners were contacted to obtain outcome data.

Results

Median age and weight of dogs were 17 mo (6 to 60 mo) and 48.5 kg (14 to 73.3 kg). Median surgical and anesthesia times were 90 min (60 to 150 min) and 195 min (135 to 270 min). Major intraoperative complications were not reported. Follow-up data were available for 40/44 (91%) dogs. Median follow-up time was 522 d (43 to 983 d). Gastric dilatation volvulus (GDV) was not reported in any dog. One dog developed suspected colonic entrapment around the gastropexy that required surgical revision. All owners were satisfied with the procedure and indicated they would repeat the procedure with future pets.

Conclusion

The PTLG procedure using novel KTCD in this cohort of dogs was effective at preventing GDV for the duration of follow-up and was associated with low perioperative complication rate and high owner satisfaction.

Clinical relevance

This retrospective study reports on operative technique and outcomes associated with KTCD use in PTLG. Our findings warrant prospective evaluation of KTCD use in PTLG.

Introduction

Gastropexy is a prophylactic procedure that is considered the standard of care in preventing the occurrence or recurrence of gastric dilatation volvulus (GDV) in at-risk dog breeds (1–3). The gastropexy procedure has been described using a variety of open surgical and minimally invasive laparoscopic techniques (1–7). Total laparoscopic gastropexy has been associated with decreased postoperative pain, as demonstrated by increased willingness to move during postoperative recovery, compared with open and laparoscopic-assisted techniques (4,8). Total laparoscopic gastropexy also allows for the laparoscopic completion of additional procedures, such as sterilization procedures including ovariectomy (9–11), ovariohysterectomy (12), and cryptorchidectomy (13,14).

Total laparoscopic gastropexy techniques have been described using intracorporeal knot-tying (6–8), specialized knot-tying (8), stapling (15), and knotless barbed suture (4,16,17), to create a permanent adhesion between the pyloric antrum’s seromuscular layer and right transversus abdominus. Knotless barbed suture has been demonstrated superior to manual knot-tying of standard suture because it required less significant manual dexterity and is associated with a faster suturing speed and an evenly distributed suture tension (17–22). In addition, compared to intracorporeal knot-tying with standard suture, barbed suture has been shown to have similar (16) or increased (22) biomechanical strength in laparoscopic gastropexy procedures.

Prophylactic total laparoscopic gastropexy (PTLG) has been described using knotless barbed suture in either a single simple continuous line (4) or 2 simple continuous lines between the seromuscular layer of the pyloric antrum and right transversus abdominus muscle. STRATAFIX Symmetric PDS Plus Knotless Tissue Control Device (KTCD) (Ethicon, Johnson & Johnson, Cincinnati, Ohio, USA) is a novel barbed suture that contains unidirectional barbs and has a prominent tab at its terminus (Figure 1) (20). This novel KTCD has been shown to be comparable to the V-Loc 180 Wound Closure Device (Medtronic, Covidien, Cambridge, Massachusetts, USA) when comparing load to failure and handling properties in a canine cadaveric gastropexy model (21). The V-Loc 180 is another type of knotless barbed suture and has been described in PTLG techniques (4). The V-Loc 180 suture also contains unidirectional barbs; however, it has a loop at its terminus (23). The objective of this study was to report on operative technique and outcomes following PTLG using a novel KTCD. It was hypothesized that use of the KTCD in PTLG would be associated with a low perioperative complication rate and be effective at preventing occurrences of GDV in this cohort of dogs within the follow-up period.

Figure 1.

Photograph of the STRATAFIX Symmetric PDS Plus Knotless Tissue Control Device (Ethicon, Johnson & Johnson, Cincinnati, Ohio, USA) used in prophylactic total laparoscopic gastropexy.

Materials and methods

Case selection and medical record review

Medical records in an electronic database were reviewed to identify dogs that underwent PTLG using a KTCD in 2 simple continuous lines between June 2019 and May 2022. Any dogs undergoing open gastropexy or undergoing PTLG using a suture material other than a KTCD were excluded from the study. The duration of surgery, defined as time from initial skin incision to final closure (in min), and the duration of anesthesia, measured from the time of induction to the time of extubation (in min), were recorded. The duration of hospitalization, measured from the time of admission to the time of discharge (in h), was also recorded.

Complications reported during PTLG that resulted in considerable deviation from routine operative technique were classified as intraoperative complications. Complications in the postoperative period were classified as minor or major: Complications that did not require veterinary intervention and resolved with supportive care were classified as minor, and complications that required veterinary intervention were classified as major (24).

Outcome

Survey questions were distributed electronically (via email) or by telephone to owners between January 2022 and June 2022 (see Appendix 1, available online from: www.canadianveterinarians.net), and all answers were recorded. The minimum time to follow-up requirement was 30 d after PTLG, to allow for a period of recovery from the procedure. The date of follow-up with the dog’s owners, defined as date of survey completion, and the total follow-up time, defined as duration (in d) from the date of gastropexy surgery to the date of follow-up, were recorded.

Anesthetic protocol

All dogs were anesthetized with routine, non-standardized anesthetic protocols approved by an American College of Veterinary Anesthesia and Analgesia (ACVAA) Board-certified anesthesiologist. All dogs were intubated with an appropriately sized endotracheal tube and maintained with either isoflurane or sevoflurane delivered on 100% oxygen and titrated to effect to achieve an appropriate anesthetic depth. Cefazolin (22 mg/kg, IV) was given to all dogs 30 min before the first skin incision, and then every 90 min until extubation.

Surgical technique

Total laparoscopic gastropexy using the knotless tissue control device

All procedures were performed by a single American College of Veterinary Surgeons (ACVS) Board-certified surgeon (AS) or by ACVS residents under direct supervision. In each dog, the ventrolateral abdomen from xiphoid to pubis was clipped and aseptically prepared for surgery. The dog was positioned in dorsal recumbency and secured to the operating table. The ventrolateral abdomen was draped in a fashion to perform a celiotomy should conversion to an open procedure be required. A 2.5-centimeter skin and subcutaneous incision was made 2 to 5 cm caudal to the umbilicus and the linea alba was identified. Stay sutures of 0 PDS II (Ethicon, Johnson & Johnson, Bridgewater, New Jersey, USA) were placed on either side of the linea alba. A stab incision was made in the linea alba, the incision was extended to 2.5 cm, and a single-incision laparoscopic surgery port (SILS) (Medtronic, Covidien) was inserted into the abdomen. The abdomen was insufflated with CO₂ to an intra-abdominal pressure of 8 to 10 mmHg using a mechanically regulated insufflator (Karl Storz Endoscopy, Goleta, California, USA) and 3 5-millimeter cannulae were inserted. A 5-millimeter, 30° laparoscope was inserted into the abdomen through the SILS port. One 5-millimeter cannula was removed and replaced with a 12-millimeter cannula. The abdominal viscera, including diaphragm, spleen, liver, gallbladder, stomach, and duodenum, were visualized. Intracorporeal procedures such as ovariectomy (9–11), ovariohysterectomy (12), or cryptorchidectomy (13,14) were performed at this time. Following completion of these intracorporeal procedures, 2 6-millimeter instrument portals were inserted on the ventral midline. A single temporary stay suture using 0 PDS was inserted through the body wall ~2 to 4 cm caudal to the last rib and ~3 to 5 cm lateral to the ventral midline, using endoscopic guidance to confirm landmarks. The needle was left in place at the level of the body wall to allow for accurate instrument portal placement. The 1st instrument portal was placed on the ventral midline perpendicular to location of this stay suture, using endoscopic guidance to avoid the falciform ligament. The 2nd instrument portal was placed on the ventral midline centred between the SILS port and the 1st instrument portal. With the laparoscope in the SILS port, endoscopic needle drivers (Ethicon, Johnson & Johnson) were inserted through the instrument ports. The needle of the stay suture was then grasped, and the stay suture was placed at the most aboral location of the proposed gastropexy site at the pyloric antrum. The needle was then exited transabdominally and grasped extracorporeally. The suture was tightened to elevate the stomach to the level of the body wall.

A 5-millimeter endoscopic J-hook electrosurgery tip (Medtronic, Covidien) powered at 15 W was used to create a 3- to 4-centimeter linear incision through the right transversus abdominus muscle, parallel to its fibres. The same electrosurgery tip at 15 W power was used to scarify a 3- to 4-centimeter linear area at the proposed location of a seromuscular incision between the lesser and greater curvature of the pyloric antrum. Endoscopic scissors were used to create a seromuscular incision through the predetermined scarified region. The terminal tab of the KTCD prevents transabdominal passage, so an alternate strategy was employed to place the suture material transabdominally. The cap of the 12-millimeter cannula in the SILS port was removed and an endoscopic needle driver was pre-placed through the cap. The needle of the size 2-0 KTCD was then grasped with the same needle driver and the suture wound along the tip of the instrument (Figure 2). The cap of the 12-millimeter cannula was placed 4 to 6 cm from the tip of the needle driver, and then the instrument was inserted into the abdomen through the 12-millimeter cannula in the SILS port, with the cap secured rapidly to minimize loss of pneumoperitoneum. The laparoscope was inserted into the middle instrument portal and, using laparoscopic guidance to prevent iatrogenic trauma, the suture needle was visualized as it entered the abdomen and was subsequently grasped using endoscopic needle drivers inserted through the cranial instrument portal. The laparoscope was removed from the middle instrument cannula and a 5-millimeter cannula was inserted in the SILS port. The 2nd endoscopic needle driver was removed from the 12-millimeter cannula in the SILS port and inserted into the middle instrument cannula.

Figure 2.

Photograph of the 2-0 knotless tissue control device needle grasped with the suture wound along the tip of the endoscopic needle driver.

The cranial wound edge of the transversus abdominus and pyloric antrum were opposed using 2-0 KTCD (Figure 1). The initial suture bite was through the seromuscular layer of the stomach, ensuring the tab was fixed to the tissue layer. This suture line was completed with 1 or 2 reverse passes and the needle was cut using endoscopic scissors, leaving a minimum of 1 cm of suture. The needle was then exited transabdominally and grasped extracorporeally. The same procedure was repeated on the caudal wound edges with a second line of 2-0 KTCD inserted into the abdomen as described herein. The initial bite was placed through the body wall, ensuring the tab was fixed to the tissue layer. The needle was exited as described herein. The stay suture on the pyloric antrum was removed and the abdomen was deflated of CO₂ following instrument and SILS port removal.

Postoperative care

All dogs were monitored and received postoperative supportive care in-hospital until the time of discharge. Postoperative analgesia and follow-up recommendations were according to the discretion of the attending clinician.

Statistical analysis

Descriptive statistics, including measures of central tendency (median) and dispersion (range), were calculated for dog age and weight, surgical and anesthesia time, and duration of hospitalization. Numbers and percentages were used to report all categorical variables.

Results

Study population

Forty-four dogs met the inclusion criteria for this study: 23 intact females, 14 intact males, 5 castrated males, and 2 spayed females. Sixteen Great Danes, 6 German shepherds, 5 mixed-breed dogs, 3 Saint Bernards, 3 mastiffs, and 11 dogs of other breeds were included. The median age at time of gastropexy was 17 mo (range: 6 to 60 mo) and the median weight was 48.5 kg (range: 14 to 73.3 kg). All dogs were admitted for PTLG and were confirmed to have an anatomically normally positioned stomach at the time of the procedure.

Surgical approach and concurrent procedures

Prophylactic total laparoscopic gastropexy was successfully completed in all dogs. Forty-one dogs received concurrent procedures. Twenty-three dogs underwent single intra-abdominal laparoscopic procedures, including ovariectomy (15/44), ovariohysterectomy (5/44), gastric/jejunal/ileal biopsies (1/44), umbilical herniorrhaphy (1/44), and colopexy (1/44). Three dogs underwent multiple intra-abdominal procedures, including laparoscopic ovariectomy and umbilical herniorrhaphy (2/44) and bilateral laparoscopic cryptorchidectomy and umbilical herniorrhaphy (1/44). Eleven dogs underwent extra-abdominal procedures, including open pre-scrotal castration (10/44) and upper gastrointestinal endoscopy (1/44). Two dogs underwent both intra- and extra-abdominal procedures, including unilateral laparoscopic cryptorchidectomy, unilateral open pre-scrotal castration, and bilateral dew claw amputation (1/44); and unilateral laparoscopic cryptorchid castration and unilateral open pre-scrotal castration (1/44). The median total surgical and anesthesia times were 90 min (range: 60 to 150 min) and 195 min (range: 135 to 270 min), respectively.

Intraoperative complications and duration of hospitalization

Minor intraoperative surgical complications were reported in 1 dog and included minor hemorrhage of the ovarian pedicle during laparoscopic ovariectomy that was addressed intracorporeally. Mild reduction in PCV was noted immediately after surgery; however, it remained within normal limits and the dog’s anesthetic and surgical recovery were unremarkable. The dog was discharged 24 h after surgery without complication. No dogs required conversion to open celiotomy for PTLG or any concurrent intra-abdominal laparoscopic procedures. All dogs recovered from anesthesia and were discharged from the hospital. The median duration of hospitalization was 24 h (range: 8 to 72 h).

Follow-up

Follow-up was available for 91% (40/44) of the dogs, with a median follow-up time of 522 d (range: 43 to 983 d). Seventy percent (28/40) of dog owners followed up via an electronic survey and 30% (12/40) of owners followed up via a telephone interview. All owners who followed up completed the survey questions in its entirety. No dogs (0/40) were reported to be diagnosed with GDV following PTLG. Two dogs (2/40) reportedly experienced short-term postoperative complications, 1 minor and 1 major. One of these dogs (n = 1, minor) experienced a surgical site infection that resolved spontaneously without requiring veterinary medical intervention. The other dog (n = 1, major) experienced vomiting 3 d after surgery, and abdominal imaging revealed a malpositioned colon. An exploratory celiotomy was performed and there was a colonic volvulus around the original gastropexy site. The colon was repositioned to its proper anatomical site. The gastropexy appeared in a normal location and was intact; however, it was revised and placed in a more cranial location. The dog was hospitalized for 72 h post-celiotomy, recovered uneventfully, and experienced no further complications. No long-term complications were reported in any dog. One hundred percent (40/40) of the dog owners reported that they were satisfied with the outcome of the PTLG procedure, they would elect to have this procedure performed on future pets, and they would recommend this procedure to other dog owners.

Discussion

The results of this retrospective study demonstrated that the use of the KTCD for PTLG in this cohort of dogs was effective at preventing the occurrence of GDV within the follow-up period (43 to 983 d) and was associated with a low rate of perioperative complications and high owner satisfaction. Based on these findings, we accept our hypothesis that using a novel KTCD when performing PTLG is effective at preventing the occurrence of GDV in at-risk dogs.

The KTCD used in this study is an antibacterial, monofilament, absorbable suture containing robust unidirectional barbs spaced 180° apart; and is terminated by a prominent tab (20). Its maximum tensile strength at size 2-0, defined by constant strain until rupture, was 10.72 lbs (SD: 0.8 lbs), which was substantially higher than that of the equivalently sized PDS Plus suture knots, at 7.32 lbs (SD: 0.7 lbs) (20). In a canine cadaveric gastropexy model, this KTCD has been shown to be comparable to V-Loc when load-to-failure, handling properties, and surgical time were evaluated (21). Although KTCD is more expensive than standard PDS suture, there has been a rapid increase in published reports on the use of this novel KTCD in human gynecologic (20), orthopedic (25), and general surgery (26).

In this study, an alternative strategy for inserting the KTCD into the abdomen was required because of the prominent tab at the terminal end of the suture that is used to anchor the line that prevents its transabdominal passage. The prominent tab is an alternative to a welded eyed loop at the terminal end, as used by several other knotless sutures, and requires the surgeon to pass the needle through the eyed loop to anchor the line (4,22,23,27). The eyed loop allows for the suture to be easily passed transabdominally; however, this maneuver can cause deformation and breakage of the eyed loop (27). To pass the KTCD used in this study into the abdomen, it was preloaded onto endoscopic needle-holders and inserted through a 12-millimeter cannula in the SILS port. A 12-millimeter cannula was required to fit the needle of the 2-0 KTCD. Alternatively, a single, 12-millimeter trocar/cannula assembly could have been used in any of the port locations to allow for KTCD insertion. The authors preferred the use of the SILS port as most dogs required concurrent sterilization procedures, which were performed in a single-port fashion before the addition of the 2 instrument portals for the PTLG.

The authors preferred use of the J-hook electrosurgery tip to scarify a shallow mark at the site of incision between the lesser and greater curvature of the pyloric antrum. The purpose of this initial scarification was to minimize bleeding. Endoscopic scissors were then used to ensure full-thickness incision of the seromuscular layer overlying the scarified mark. This technique minimized the risk of incising through the submucosa-mucosa and entering the gastric lumen.

All anesthetic protocols were non-standardized due to variations in patient temperament, comorbidities, and preanesthetic physical examination findings. All dogs received opioid pain medication (hydromorphone, 0.025 to 0.05 mg/kg or methadone, 0.2 to 0.4 mg/kg, IM or IV) as part of their complete anesthetic protocol. Testicular blocks with lidocaine were performed in dogs undergoing concurrent pre-scrotal (bilateral and cryptorchid) open castration (12/44). At the discretion of the attending clinician, postoperative analgesic protocols were also routine; however, these were not standardized due to variations in patient temperament, comorbidities, and any concurrent procedures completed.

Median surgical time for the dogs in this study was 90 min (range: 60 to 150 min), which is similar to that in previous reports on PTLG in dogs; the wide range was likely the result of various levels of resident training during the procedure and the variety of concurrent procedures completed (6,17,24). Based on the retrospective nature of this study, we could not separate surgical times between PTLG and concurrent procedures. However, as performing concurrent sterilization with PTLG is a common clinical scenario, the utility of separating surgical times between procedures is likely minimal. The median hospitalization time of 24 h for dogs undergoing PTLG in this study was consistent with previous reports (4,8).

Intraoperative complications were reported in a single dog that were unrelated to the PTLG but instead were a result of ovarian pedicle hemorrhage at the time of concurrent ovariectomy. The dog recovered without complication and was discharged 24 h after surgery. Intraoperative complications related to the PTLG or KTCD were not reported in any dog, suggesting the KTCD was easy to use and the surgical team was familiar with the PTLG procedure. Previous concerns related to breakage of the welded loop of the terminal end during transabdominal passage of other types of barbed sutures were not encountered due to the tab configuration of the terminal end of the KTCD.

A major postoperative complication encountered in 1 dog was vomiting 3 d after surgery. Malpositioning of the colon was suspected based on abdominal ultrasonography. Open exploratory celiotomy revealed colonic malpositioning or entrapment around the PTLG site. The gastropexy itself was unremarkable but was revised at the time of open celiotomy and the colon returned to its normal anatomical location. Long-term follow up of this dog at 503 d revealed no further abnormalities. Colonic entrapment around a gastropexy site has previously been reported in dogs (28). Although the exact predisposing factors for colonic entrapment around a gastropexy site are unclear, surgeons should ensure appropriate anatomical positioning of the stomach and colon at the time of PTLG.

Follow-up information was obtained from 40/44 (91%) dog owners with a median follow-up time of 522 d (range: 43 to 983 d). All dogs were reported by their respective owners to be currently healthy and not diagnosed with a GDV, suggesting that the use of KTCD during PTLG is effective at preventing GDV in at-risk dog breeds. In addition, and consistent with previous reports, 100% of owners reported that they were satisfied with the outcome of PTLG procedure, they would elect to have this procedure performed on future pets, and they would recommend this procedure to other dog owners (17,24).

Limitations of this study are related to its retrospective nature. Follow-up was performed with the dog owners and not the referring veterinarians, which may have altered minor complication rates. The authors believe that major complications would likely have been noted by owners, who would have needed to seek veterinary attention for issues such as, but not limited to, GDV or wound complications. Ultrasonography of the gastropexy has been reported to evaluate the site with consistency and repeatability (4,8,17,29–31). Within 3 mo after gastropexy, ultrasound findings are expected to show a focal inflammatory hyperechoic tissue line extending from the pyloric wall to the abdominal wall, with or without mild peritoneal effusion (4,17,30). Follow-up ultrasonography was not completed for the dogs in this study; therefore, it cannot be confirmed whether the PTLG has remained intact in each case since the time of surgery. Clinical examinations for suture removal and recovery progress evaluation were completed either by the Ontario Veterinary College Surgery Service (Guelph, Ontario) or by the referring veterinarians, and no occurrences of GDV were reported at these times.

In summary, this retrospective, single-institutional study demonstrated that the use of a novel KTCD for PTLG in dogs was associated with a low rate of perioperative complications and a high rate of owner satisfaction. Future work involving this novel KTCD in PTLG should include prospective investigations that allow for comparisons to additional knotless barbed sutures.