Effect of presurgical storage conditions on leakage pressures of enterotomy sites closed with unidirectional barbed suture material in fresh, chilled, and frozen-thawed cadaveric canine jejunal specimens

Influence of barbed suture oversew of the transverse staple line during functional end-to-end stapled anastomosis in a canine jejunal enterectomy model

Objective

To evaluate the influence of barbed suture oversew of the transverse staple line during functional end‐to‐end stapled anastomosis (FEESA) in dogs.

Study design

Randomized, experimental, ex vivo.

Animals or sample population

Grossly normal jejunal segments from 14 adult canine cadavers.

Methods

Ninety‐eight jejunal segments (n = 14/FEESA group, n = 14 controls) were harvested and randomly assigned to a control group, FEESA + monofilament suture oversew, FEESA + unidirectional barbed suture oversew or FEESA + bidirectional barbed suture oversew. Oversew techniques were performed using a Cushing suture pattern. Initial (ILP) and maximum leakage pressure (MLP), repair time (s), and location of observed leakage were recorded.

Results

No differences were detected in ILP (p = .439) or MLP (p = .644) respectively between experimental groups. Repairs times using barbed suture were ~ 18% faster (~25 s faster; p < .001) compared to monofilament suture. There was no difference between barbed suture types (p = .697). Mean ILP (p < .001) and MLP (p < .0001) were 6.6x and 5.1x greater respectively in the control group. Leakage location occurred predominately at the crotch of the FEESA in all groups.

Conclusion

FEESAs closed with a transverse staple line oversew using barbed suture, regardless of barb orientation, were completed faster and resulted in similar resistance to anastomotic leakage compared to monofilament suture.

Clinical significance

Oversewing the transverse staple line following FEESA using barbed suture offers similar resistance to anastomotic leakage, and may be associated with decreased surgical times in dogs compared to monofilament suture. Further studies are necessary to determine the benefits of barbed suture use in both open and laparoscopic gastrointestinal surgical applications following FEESA in dogs.

Ex vivo comparison of different thoracoabdominal stapler sizes for typhlectomy in canine cadavers

OBJECTIVE

To determine the influence of staple size on leakage pressure of typhlectomy sites in canine cadavers.

STUDY DESIGN

Randomized, experimental cadaveric study.

ANIMALS

Twenty-four fresh canine cadavers.

METHODS

Ileocecocolic segments were exteriorized following right paracostal laparotomy after euthanasia. Cecal base length and wall thickness were measured. Each cecum was randomly assigned to 1 of 3 groups (TA 30 V3 2.5 mm, TA 60 3.5 mm, and TA 60 4.8 mm). The cecal base was stapled and the cecum was removed. A 10 cm segment including the stapled cecal excision site was tested for initial leak pressure.

RESULTS

The mean ± standard deviation body weights across the groups were 18.7 ± 6.1 kg, 16.2 ± 7.5 kg, and 14.2 ± 5.5 kg for the TA 30 V3 2.5 mm, TA 60 3.5 mm, and TA 60 4.8 mm groups, respectively (P = .48). There were no differences for mean cecal base length or wall thickness. Mean initial leak pressure (ILP) across groups was 182 ± 111 mmHg (TA 30 V3 2.5 mm), 112 ± 57 mmHg (TA 60 3.5 mm), and 77 ± 60 mmHg (TA 60 4.8 mm) (P = .78).

CONCLUSION

Each stapler size that was evaluated resulted in a mean ILP in excess of typical intraluminal pressures under normal circumstances. There were no differences among groups.

CLINICAL SIGNIFICANCE

The results of this cadaveric study support the use of any of the stapler sizes evaluated in similarly sized dogs. A prospective study is needed to be able to correlate stapler size and clinical outcome.

Influence of crotch suture augmentation on leakage pressure and leakage location during functional end-to-end stapled anastomoses in dogs

OBJECTIVE

To determine the influence of anastomotic crotch suture augmentation on leakage pressures and leakage location following intestinal functional end-to-end stapled anastomosis (FEESA) in dogs.

STUDY DESIGN

Ex vivo, randomized, experimental.

SAMPLE POPULATION

Chilled jejunal segments from 3 adult dogs.

METHODS

Jejunal specimens were tested within 24 hours of collection. A FEESA was performed and randomly assigned to 1 of 4 treatment groups (n = 12/group): (1) no crotch suture (NCS); (2) simple interrupted crotch suture (SICS); (3) two simple interrupted crotch sutures (TCS) placed laterally on opposing jejunal limbs; (4) simple continuous crotch suture (SCCS) augmentation. Crotch sutures were performed using 3-0 USP polydioxanone. Initial (ILP) and maximal (MLP) leakage pressures (Mean ± SD mm Hg) and leakage location were recorded and compared between groups.

RESULTS

Initial leakage pressure was greater after placement of TCS (37.8 ± 6.4, P < .039) and SCCS (47.6 ± 11.0, P < .002) than NCS (27.1 ± 2.5) and SICS (33.0 ± 6.0). Maximal leakage pressure was greater in specimens including SICS, TCS, and SCCS than those without crotch suture augmentation (P < .043). Leakage occurred at the anastomotic crotch in 8/12 NCS, 6/12 SICS, 11/12 TCS, and 12/12 SCCS constructs (P < .001).

CONCLUSION

Augmentation of FEESA with TCS and SCCS increased ILP and decreased the occurrence of leakage from the anastomotic crotch, while all methods of anastomotic crotch augmentation increased MLP.

CLINICAL SIGNIFICANCE

Augmenting the FEESA with crotch suture(s) improved the resistance of the jejunal anastomosis to leakage in normal cadaveric segments. Placing 2 crotch sutures or use of a simple continuous pattern for anastomotic augmentation appeared to be superior to the placement of a single suture.

Influence of preconstructed effector loop location using a barbed unidirectional suture on leakage pressures following canine enterotomy closure

OBJECTIVE

To evaluate the influence of preconstructed effector loop location using a barbed unidirectional suture on leakage pressures following canine enterotomy closure.

STUDY DESIGN

Randomized, experimental, cadaveric.

ANIMALS OR SAMPLE POPULATION

Grossly normal jejunal segments from three canine cadavers.

METHODS

Jejunal segments were harvested and randomly assigned based upon effector loop location from the beginning of the incisional line. Groups (n = 12/group) included 0 mm, 5 mm, 10 mm, 15 mm, and intact controls (n = 6/group), repaired using a 3-0 unidirectional barbed suture in a simple continuous pattern. Initial leakage pressure (ILP), maximum intraluminal pressure (MIP), repair time, and leakage location were recorded.

RESULTS

Mean ILP for 0 mm group (24.42 ± 8.43 mmHg) was lower (p ≤ .001) compared to all experimental groups with ILP ~40% lower. There was no difference in MIP among experimental groups (p = .239). Repair time increased (p < .0001) as the distance of the effector loop increased ≥5 mm from the beginning of the incisional line. Leakage location differed among groups (p < .001) with leakage in the 0 mm group from the incisional line (75%), compared to leakage from predominantly from the suture holes in other groups, respectively.

CONCLUSION

Effector loop location influenced ILP and leakage location. Effector loops placed at the beginning of the incisional line (0 mm) decreased ILP compared to loops placed at 5, 10, and 15 mm.

CLINICAL SIGNIFICANCE

Effector loop location using a unidirectional barbed suture should be placed ≥5 mm from beginning of the incisional line for enterotomy closure. Further in vivo studies are necessary to determine the clinical significance of these findings.

Ex vivo comparison of hand-sutured versus circular stapled anastomosis in canine large intestine

OBJECTIVE

To compare leakage pressures of colonic anastomoses performed with circular staplers to conventional hand-sewn techniques in dogs.

STUDY DESIGN

Ex-vivo study.

ANIMALS

Colon from 11 canine cadavers.

METHODS

Thirty-two colonic anastomoses were performed. Four segments from each colon were randomly assigned to one of four techniques: hand-sewn colonic anastomoses performed with 4-0 glycomer 631 (G) and 4-0 barbed glycomer 631 (BG), and circular stapled colonic anastomoses using 4.8 mm End-to-End Anastomosis (EEA C4.8mm) and 3.5 mm End-to-End Anastomosis (EEA C3.5mm), 21 mm diameter circular staples in cadaveric canine colon. Leakage pressure was defined as the pressure at which dye-containing solution was first observed to leak from the anastomosis site.

RESULTS

Leakage pressures were 49.5 mmHg (range:16-72) in group G, 45.5 mmHg (range:19-80) in group BG, 5.3 mmHg (range:0-31) in group C3.5mm, and 29.5 mmHg (range:23-50.3) in group C4.8mm. Anastomoses leaked at lower pressures when stapled rather than hand-sewn (C4.8mm-G p = .0313, C4.8mm-BG p = .0131, C3.5mm-G p = .0469, C3.5mm-BG p = .0313). Two of the C3.5mm constructs leaked immediately after saline infusion with 4/6 leaking at <5.3 mmHg.

CONCLUSION

End-to-end colonic anastomoses closed with circular stapler leaked at lower pressures than hand-sutured anastomoses. Use of the EEA stapler with a staple height of 3.5 mm did not result in safe colonic anastomoses.

CLINICAL SIGNIFICANCE

These results provide evidence to support hand-suturing colonic anatomoses with G and BG in dogs. The 4.8 mm staples may be considered in anatomical locations difficult to reach.

Ex vivo comparison of leak testing of canine jejunal enterotomies: Saline infusion versus air insufflation

OBJECTIVE

To compare the ability to detect leakage of enterotomy closures by intraluminal injection of saline or air.

STUDY DESIGN

Ex vivo study.

ANIMALS

Grossly normal jejunal segments (n = 60) from five fresh canine cadavers.

METHODS

Eight-centimeter jejunal segments were randomly assigned to two control (saline control [n = 5], air control [5]) and two treatment groups (injection of saline [n = 25] or air [25] after enterotomies were closed in a simple continuous pattern using 4-0 glycomer 631). Initial leak pressure (ILP, mean ± SD), maximum intraluminal pressure (MIP), and leakage location were compared. For all air insufflation constructs, the volume of air insufflated at the time of initial leakage was recorded.

RESULTS

The ILPs of control segments did not differ whether injected with saline (405.71 ± 56.97 mmHg) or air (376.84 ± 42.54, p = 1.00). Enterotomy closures leaked at lower pressures when injected with air (ILP: 68.52 ± 6.56) compared to saline (87.76 ± 5.20, p = .03). Similar results were obtained when comparing MIPs. A moderate association (r = .51) was identified between volume of air infused and ILPs. The strength of the association improved when stratified by cadaver. The location of leakage-most commonly suture tracks-was identified for all air constructs and for 14 of 25 saline constructs.

CONCLUSION

Enterotomy closures leaked at lower pressures after intraluminal injection of air compared to saline.

CLINICAL SIGNIFICANCE

Intraoperative leak testing of small intestinal enterotomy closures may be rendered more sensitive and precise by the use of air instead of saline as the infusate.

Biomechanical properties of canine staphylectomies closed with barbed or smooth suture

OBJECTIVE

To compare the duration of closure and biomechanical properties of staphylectomies closed with absorbable bidirectional barbed suture or smooth monofilament suture in a simple continuous or interrupted pattern STUDY DESIGN: Ex vivo study SAMPLE POPULATION: Soft palates (n = 60) harvested from mesaticephalic canine cadavers METHODS: One centimeter of tissue was excised from the caudal border of each soft palate, and the oral and nasopharyngeal mucosal surfaces were apposed with 2-0 bidirectional Quill Monoderm knotless closure device barbed suture (Q), 3-0 Monocryl in a simple continuous (MC) pattern, or 3-0 Monocryl in a simple interrupted (MI) pattern (n = 20 per group). Duration of closure was compared between groups. Tissues were tested under tension to failure, and mode of failure data were collected by video capture.

RESULTS

Closure time was longer for MI closures than for Q and MC closures, with means of 259.9, 215.4, and 196.7 seconds, respectively (P < .0001). No difference was detected in yield force, force to first tissue rupture, maximum force, and energy required for yield and maximum force between groups. Energy to yield was 190.0, 167.8, and 188.95 N-mm for MI, Q, and MC closures, respectively.

CONCLUSION

Biomechanical properties of staphylectomies closed with barbed or smooth sutures did not differ in this cadaveric model.

CLINICAL SIGNIFICANCE

Barbed suture can be considered as an alternative for closure of canine staphylectomies. These results provide evidence to justify additional research to evaluate clinical outcomes in dogs undergoing staphylectomy.