Daniel Dwight Smeak

OBJECTIVE: To compare 3 anal purse-string suture techniques for resistance to leakage and to identify the suture technique requiring the fewest tissue bites to create a consistent leak-proof orifice closure. ANIMALS: 18 large-breed canine cadavers. PROCEDURES: 3 purse-string suture techniques (3 bites with 0.5 cm between bites [technique A], 5 bites with 0.5 cm between bites [technique B], and 3 bites with 1.0 cm between bites [technique C]) were evaluated. Each technique involved 2-0 monofilament nylon suture that was placed in the cutaneous tissue around the anus and knotted with 6 square throws. Standardized 2.0-cm-diameter circular templates with the designated bite number and spacing indicated were used for suture placement. Leak-pressure testing was performed, and the pressure at which saline was first observed leaking from the anus was recorded. The median and interquartile (25th to 75th percentile) range (IQR) were compared among 3 techniques. RESULTS: Median leak pressure for technique A (101 mm Hg; IQR, 35 to 131.3 mm Hg) was significantly greater than that for technique C (19 mm Hg; IQR, 14.3 to 25.3 mm Hg). Median pressure did not differ between techniques A and B (50 mm Hg; IQR, 32.5 to 65 mm Hg) or between techniques B and C. CLINICAL RELEVANCE: Placement of an anal purse-string suture prevented leakage at physiologic colonic and rectal pressures, regardless of technique. Placement of 3 bites 0.5 cm apart (technique A) is recommended because it used the fewest number of bites and had the highest resistance to leakage.

The perineal urethrostomy (PU) technique has only been vaguely described in the dog. Additionally, details of short- and long-term postoperative complications are not well documented. The purpose of this study was to provide a detailed description of PU in male dogs and describe the postoperative course. Eight adult, intact, male, mixed-breed dogs were used for this study. A perineal urethrostomy was performed on each, using the described technique. Dogs were assessed daily for 70 to 419 d after surgery, and stoma site patency was assessed at planned intervals using a 12 French Foley catheter as well as a 5.5-mm rigid cystoscope. Surgical time and short- and long-term complications were recorded. The perineal urethrostomy stoma sites of all 8 dogs were determined to be patent and no strictures were identified during the entire time course of this study. No major complications occurred during the follow-up period. Three dogs developed minor, self-resolving incisional dehiscence. The mean surgery time was 62.9 +/- 14.1 minutes (mean +/- SD). Canine perineal urethrostomy as described can be performed with minimal short- and long-term complications.

OBJECTIVE To compare the volume of saline (0.9% NaCl) solution required to reach a maximum intraluminal peristaltic pressure of 25 mm Hg in dogs of various sizes. SAMPLES 25 grossly normal jejunal segments from 6 canine cadavers < 20 kg (small dogs) and 25 segments from 5 cadavers >= 20 kg (large dogs). PROCEDURES Jejunal specimens were obtained within 1.5 hours after euthanasia. Harvested tissue was transected into 12-cm-long segments, mesentery was trimmed, and each segment was measured from the antimesenteric to mesenteric serosal edges. A 10-cm segment was isolated with Doyen forceps, securing a pressure sleeve within the lumen. Intraluminal saline was infused, and the volume was recorded when a pressure of > 25 mm Hg was achieved. Data were analyzed only from specimens in which the pressure remained between 24 and 26 mm Hg for > 5 seconds. RESULTS Mean +/- SD intestinal measurement for large dogs (17.82 +/- 1.44 mm) was greater than that for small dogs (12.38 +/- 1.38 mm) as was the volume of saline solution infused (17.56 +/- 7.17 mL vs 3.28 +/- 1.41 mL, respectively). The volume infused increased by 1.31 mL (95% CI, 1.08 to 1.18) for every 1-mm increase in intestinal measurement and by 1.06 mL (95% CI, 1.052 to 1.068) for every I-kg increase in body weight. CONCLUSIONS AND CLINICAL RELEVANCE The volume of saline solution used for intestinal leak testing should be determined on the basis of patient intestinal measurement or body weight. In vivo studies are necessary to establish the optimal volume for intestinal leak testing.

Objective To compare the detection of gaps in jejunal continuous anastomoses by probing (PT) versus leak testing (LT). Study Design Experimental study. Animals Normal jejunal segments (n = 24) from two fresh canine cadavers. Methods Intestinal segments were randomly selected by four volunteers who created six simple continuous anastomoses: two constructs using standard technique with 2–3 mm suture spacing (ST, 8 total), and four constructs with one 4-mm gap (IG, 16 total). All 24 anastomoses were examined with PT (1 volunteer) prior to LT (3 volunteers). LT was performed within a maximal peristaltic pressure range (34–54 cmH₂O). The presence and location of anastomotic leaks (L_A) detected with LT were compared with gaps detected with PT. Results Nineteen out of twenty-four (79.2%) samples had at least one probe drop, and four out of twenty-three (17.4%) samples leaked. LT results from one sample were excluded due to iatrogenic suture failure. PT was 100% sensitive (95% CI: 51.01, 100%) with a 100% negative predictive value (95% CI: 56.55, 100%) at detecting gaps compared with LT. The location of all L_A was accurately identified with PT and confirmed during LT. Conclusion PT was highly sensitive at detecting gaps compared with LT. All L_A were accurately detected by PT. None of the segments negative during PT leaked. Clinical Significance The diagnostic value of PT appears adequate to recognize gaps in cadaveric small intestinal anastomoses. PT offers surgeons an alternative to detect suture gaps that may contribute to postoperative dehiscence of intestinal anastomoses.

OBJECTIVE: To determine whether jejunal serosal patches could securely seal large, open defects in duodenal segments harvested from canine cadavers and to compare intraluminal pressures at which leakage first occurred and maximal intraluminal pressures for repaired duodenal segments between 2 suture patterns. SAMPLE: Duodenal and jejunal segments from 9 canine cadavers. PROCEDURES: 20 constructs were created through repair of large, open duodenal defects with circumferential suturing of an intact jejunal segment (jejunal serosal patch). Constructs were randomly assigned to have the serosal patch anastomosed to the duodenal segment by a simple continuous or simple interrupted suture pattern. The pressure at which the first leakage was observed and the maximum pressure obtained during testing were recorded and compared between suture patterns. RESULTS: Initial leakage pressure was significantly higher with the simple interrupted pattern (mean ± SD, 68.89 ± 5.62 mm Hg), compared with the simple continuous pattern (59.8 ± 20.03 mm Hg). Maximum intraluminal pressures did not significantly differ between the simple interrupted (91 ± 8.27 mm Hg) and simple continuous patterns (90.7 ± 16.91 mm Hg). All constructs, regardless of suture pattern, withstood supraphysiologic pressures. CONCLUSIONS AND CLINICAL RELEVANCE: Jejunal serosal patches adequately sealed large, open duodenal defects and prevented leakage in these constructs. Constructs with simple continuous or simple interrupted suture patterns withstood physiologic and supraphysiologic intraluminal pressures, although constructs with a simple interrupted suture pattern initially leaked at higher pressures. (Am J Vet Res 2020;81:985–991)

OBJECTIVE To evaluate holding security of 4 friction knots created with various monofilament and multifilament sutures in a vascular ligation model. SAMPLE 280 friction knot constructs. PROCEDURES ...

Objective To determine the value of initial aerobic bacterial cultures of acute open traumatic wounds to predict bacterial species in wounds that become infected. Study design Prospective clinical trial. Animals Sixty-four dogs with naturally occurring acute cutaneous traumatic wounds (2017-2018). Methods Initial swabs were taken from each wound prior to and after lavage and debridement for quantitative and qualitative aerobic bacterial culture. Cultures were repeated on wounds that displayed any clinical sign of infection within 14 days of presentation. Results Fewer bacteria were cultured from postlavage than from prelavage swabs in 43 of 50 (86%) acute wounds. All primary clinicians prescribed beta-lactam antibiotics to the dogs at initial presentation. All bacteria cultured from postlavage/debridement cultures at initial presentation were susceptible to the prophylactic antimicrobial prescribed. Postoperative infection was subsequently diagnosed in 14 of 64 (22%) dogs; 13 of these dogs had positive culture results. No correlation was detected between the results of initial wound cultures and the subsequent development of wound infection. Bacterial species present in the initial wound swab did not correlate with those subsequently cultured from infected tissues. Conclusion Results of pretreatment wound cultures from open traumatic wounds in dogs were not predictive of bacterial species subsequently recovered from infected wounds. The bacterial burden present in pretreatment wounds was not predictive of whether wounds would ultimately become infected after surgical management. Clinical significance Routine bacterial culturing of acute wounds is not likely to help predict subsequent wound infection, nor is it likely to accurately guide early selection of antimicrobials to treat wounds that become infected.

Objective: To evaluate the mechanical properties, strength, and quality of seal provided by continuous intradermal suture lines closed with barbed suture vs monofilament suture.Study design: Experimental study.Sample population: Forty‐eight full‐thickness wounds in canine cadavers.Methods: Four‐centimeter‐long parasagittal cutaneous wounds were created in canine cadavers. Each intradermal closure was closed with smooth monofilament suture and terminated with a 2 + 1 Aberdeen knot (n = 24) or a unidirectional barbed suture terminated with a single end pass (n = 24). Wounds (n = 12/group) were harvested, and a servohydraulic machine applied tensile load perpendicular to the long axis of the suture line. A load–displacement curve was generated; maximum load, displacement, stiffness, and mode of construct failure were recorded. Harvested wounds were placed in a watertight construct to measure the volume of fluid leaking over 3 minutes at 1.0 ± 0.1 psi.Results: Stiffness did not differ between constructs (P > .05). Incisions closed with monofilament sutures sustained higher maximum load (311.21 N ± 87.40) and displacement at failure (21.19 mm ± 4.51) compared with those with barbed sutures (116.38 N ± 42.82 and 15.03 mm ± 2.32, respectively, P < .05). Closures with monofilament sutures leaked more (4.38 mL ± 7.90) compared with those with barbed sutures (0.15 mL ± 0.43, P < .05).Conclusion: Monofilament sutures resulted in stronger constructs, whereas barbed suture constructs provided a better watertight seal.Clinical significance: While unidirectional barbed sutures may improve watertight skin closure, surgeons should consider using conventional monofilament sutures when mechanical strength of the closure is of primary concern.

This case report documents a novel late surgical complication in a 2 yr old dog following an enterotomy to remove a jejunal foreign body. Twenty-six days following the original surgery, the dog was re-presented with signs consistent with an intestinal obstruction. A mural intestinal abscess was found as the cause of the obstruction during exploratory surgery, and the site was successfully removed with a resection and anastomosis. Histopathology showed multifocal abscessation with cyst-like structures partially lined with mucosa. The dog recovered without complication and remains healthy 4 mo later. The exact cause of the lesion is not known; however, local contamination through a focal mucosal defect or complications related to the use of barbed suture in the original enterotomy repair may have contributed.

OBJECTIVE To compare security of continuous intradermal suture lines closed by use of barbed suture with 3 end-pass configurations or without an end-pass configuration. SAMPLE 40 full-thickness, 4-cm-long, parasagittal wounds in canine cadavers. PROCEDURES Each continuous intradermal closure was terminated with 1 of 3 end-pass techniques or without an end-pass configuration (control group). A servohydraulic machine applied tensile load perpendicular to the long axis of the suture line. A load-displacement curve was generated for each sample; maximum load, displacement, stiffness, mode of construct failure, and load at first suture slippage at termination (ie, terminal end of the suture line) were recorded. RESULTS Values for maximum load, displacement, and stiffness did not differ significantly among the 3 end-pass techniques, and load at first suture slippage at termination was not significantly different among the 4 groups. A 1-pass technique slipped in 5 of 9 samples; 3 of these 5 slips caused failure of wound closure. A 2-pass technique slipped in 3 of 9 samples, none of which caused failure of wound closure. Another 2-pass technique slipped in 4 of 10 samples; 2 of these 4 slips caused failure of wound closure. The control group had slippage in 10 of 10 samples; 9 of 10 slips caused failure of wound closure CONCLUSIONS AND CLINICAL RELEVANCE An end-pass anchor was necessary to terminate a continuous intradermal suture line, and all 3 end-pass anchor techniques were suitable to prevent wound disruption. The 2-pass technique for which none of the suture slippages caused wound closure failure provided the most reliable configuration.