A standardized model for in vitro testing of sutures and patches for watertight dural closure

OBJECTIVE CSF leaks are common complications of spinal and cranial surgeries. Several dural grafts and suture techniques are available to achieve watertight dural closure, but the effectiveness of these techniques remains unclear. The authors developed a standardized in vitro model to test available grafts and suture techniques alone or in combination to find the technique with the most watertight dural closure. METHODS A fluid chamber with a dural fixation device, infusion pump, pressure gauge, and porcine pericardium as a dural equivalent was assembled to provide the reusable device for testing. The authors performed dural closure in 4 different fashions, as follows: A) using running versus simple interrupted suture technique and different suture materials to close a 3-cm incision; B) selecting commonly used sealants and dural patches in combination with a running suture; C) performing duraplasty (1.5 × 1.5–cm square defect) with different dural substitutes in a stand-alone fashion; and D) performing duraplasty with different dural substitutes in a double-layer fashion. Each technique was tested 6 times. The hydrostatic burst pressure (BP) was measured and compared using the Kruskal-Wallis test or the Mann-Whitney U-test. Values are reported as mean ± SD. RESULTS There was no significant difference between the running and simple interrupted suture technique (p = 0.79). Adding a patch or sealant to a suture resulted in a 1.7- to 14-fold higher BP compared to solitary suture closure (36.2 ± 24.27 cm H2O and 4.58 ± 1.41 cm H2O, respectively; p < 0.001). The highest BP was achieved by adding DuraSeal or TachoSil (82.33 ± 12.72 cm H2O and 74.17 ± 12.64 cm H2O, respectively). For closing a square defect, using a double-layer duraplasty significantly increased BP by a factor of 4–12 compared to a single-layer duraplasty (31.71 ± 12.62 cm H2O vs 4.19 ± 0.88 cm H2O, respectively; p < 0.001). The highest BP was achieved with the combination of Lyomesh and TachoSil (43.67 ± 11.45 cm H2O). CONCLUSIONS A standardized in vitro model helps to objectify the watertightness of dural closure. It allows testing of sutures and dural grafts alone or in combination. In the authors’ testing, a running 6-0 monofilament polypropylene suture combined with DuraSeal or TachoSil was the technique achieving the highest BP. For the duraplasty of square defects, the double-layer technique showed the highest efficacy.

1314 Ad-Hoc Suturing Course Teaching: A Valuable Tool for A New Starter

Aim The study aims to assess effectiveness of a three-hour suturing skills course for healthcare professionals at a tertiary hospital in London. Intended outcomes were improvement in confidence and proficiency at simple interrupted sutures. Method Four suturing sessions were delivered over five months to healthcare workers new to the clinical setting. The session included lecture, video, and practical skills. Participants completed a pre- and post-course survey to measure confidence levels in suturing using Likert scale. Participants performed simple interrupted sutures for 10 minutes in a pre- and post-course assessment. Performance was assessed using a suturing proficiency proforma. Pre- and post-course data was compared to assess improvement. Results Fifty participants attended the course. 93% had previous suturing teaching. Pre-course confidence in simple interrupted suture was 3.1 (SD = 1.2) and post course was 4.8 (SD = 0.2). One tailed T score was 14.7, and the difference was significant (p &lt; 0.05). Pre- and post-course assessment demonstrated improvement in the following parameters and participant proportions: handling of the needle driver (50%, n = 25), adequate placement of needle driver (68%, n = 34), appropriate needle angle entering skin (60%, n = 30), following needle curve (36%, n = 18), non-touch technique (64%, n = 32), surgical knot tying (56%, n = 28). Average number of sutures completed in 10 minutes increased by 1.9 times. Conclusions The majority of participants had previously been taught suturing in other settings; however, data demonstrated improvement in confidence and performance. Ad-hoc suturing skill teaching is a valuable tool to increase confidence of healthcare workers at early stages in their careers.

344 Managing Clinical Rarities: A Unique Case of Non-Inflamed Appendix in A Port Site Hernia

Introduction Port site hernias containing the appendix are sporadically described in the literature, with most cases presenting with acute appendicitis. Cases of a normal appendix being found in such hernias are extremely rare and rarely published. Here we describe a patient with a port site hernia containing a non-inflamed appendix. The lack of similar recorded cases makes this a unique case to highlight and discuss. Case Description 81-year-old lady, with adenocarcinoma of the upper rectum, underwent a laparoscopic high anterior resection in late 2018. With 12 mm ports placed in Umbilicus and RIF. 5mm ports placed in RUQ and LUQ. The 12 mm ports were closed with deep suture closure and the skin was closed using clips. Computerised tomography (CT) imaging at one year showed local cancer recurrence and a small abdominal wall hernia in the right iliac fossa. During subsequent resection surgery, a RIF port site hernia was identified intraoperatively. The hernia sac consisted of an uninflamed appendix. The hernia was reduced and an appendicectomy was performed with the hernia being closed with interrupted suture closure. Histology of the appendix confirmed no evidence of inflammation. Discussion When a clinical rarity is encountered there is often minimal literature to guide management and decisions must be made based on surgical principles and clinical reasoning. Although here an appendicectomy was performed, resection of a normal appendix remains a contentious point in the surgical field. This case demonstrates a potential management option to guide surgeons who encounter this clinical rarity in their future practice.

The Optimal Surgical Needle for Tendon Suture: Cutting Edge or Reverse Cutting Edge?

Background. Achieving a durable connection between the lacerated tendon ends is difficult. The outcome of treatment depends on many factors. Several authors consider the properties of the surgical needle used for suturing the tendon to be important. The aim of the study— to compare the strength of the tendon suture applied with the conventional cutting edge and reverse cutting edge surgical needles in the experiment.Materials and Methods.We used porcine tendons for the experiment. The tendon fragments were divided into 2 groups of 20 tendons each. On all 40 tendons, the same type of “injury” of the tendon was simulated — using a scalpel. In the first group, the interrupted suture of the tendon was applied with a cutting edge surgical needle, in the second group — reverse cutting edge. Laboratory tests of the tendon sutures strength were performed on the improvised stand.Results.In the first (suture made with a cutting needle edge), diastasis of 2 mm was determined at an average load of 1219.5 g (m = ±76.56, where «m» is the representativeness error). Complete suture failure occurred at an average load of 1770.8 g (m = ±100.02). In this group, the thread rupture was not recorded. In the second group (a suture made with a reverse cutting edge needle), diastasis occurs with an average load of 1754.75 g (m = ±77.32). Complete suture failure occurred at an average load of 2571.25 (at m= ± 103.78). In three cases, the thread ruptured. In the second group (reverse cutting edge needle), the tendon suture strength was statistically significantly higher than in the first group. Conclusion. The tendon suture strength depends on the surgical needle properties. In tendons reconstruction the reverse cutting edge needle use is more preferable compared to the conventional cutting edge needle use.

Plaster technique for filling up a future entry at the suture hole in type A aortic dissection

Although the surgical technique for acute type A aortic dissection markedly improved in the last decade, perioperative mortality and morbidity rates remain dramatically high. Therefore, we introduce the novel “plaster technique” using the single interrupted suture with a felt and plastering the minimum dose of BioGlue® (Cryolife Inc., Kennesaw, GA, USA) into the suture hole in this report. We found that the plaster technique using a felt pledget and minimum dose of BioGlue is effective for fragile aortic walls, as in patients undergoing acute aortic dissection and is a simple, safe, and durable technique to strengthen the suture line.

Mechanical strength and hydrostatic testing of VIVO adhesive in sutureless microsurgical anastomoses: an ex vivo study

Conventional anastomoses with interrupted sutures are challenging and inevitably associated with trauma to the vessel walls. The goal of this study was to evaluate a novel alternative adhesive-based suture-free anastomosis technique that uses an intraluminal stent. Overall, 120 porcine coronary vessels were analyzed in an ex vivo model and were examined for their mechanical (n = 20 per cohort) and hydrostatic strength (n = 20 per cohort). Anastomoses were made using the novel VIVO adhesive with an additional intraluminal nitinol stent and was compared to interrupted suture anastomosis and to native vessels. Sutureless anastomoses withstood pressures 299 ± 4.47 [mmHg] comparable to native vessels. They were performed significantly faster 553.8 ± 82.44 [sec] (p ≤ 0.001) and withstood significantly higher pressures (p ≤ 0.001) than sutured anastomoses. We demonstrate that the adhesive-based anastomosis can also resist unphysiologically high longitudinal tensile forces with a mean of 1.33 [N]. Within the limitations of an in vitro study adhesive-based suture-free anastomosis technique has the biomechanical potential to offer a seamless alternative to sutured anastomosis because of its stability, and faster handling. In vivo animal studies are needed to validate outcomes and confirm safety.

Reduction of Anastomotic Time Through the Use of Cyanoacrylate in Microvascular Procedures

Background: Ever since the description of the first microvascular anastomosis, numerous alternative methods have been described to the classical approach. Tissue adhesive has shown promising result in previous studies and can be a fast and efficient alternative which still requires more studies to allow its clinical implementation. Methods: A randomized comparative experimental study was conducted on rats’ femoral arteries and an end-to-end anastomosis was performed in order to compare 2 anastomosis techniques. In one group, a simple interrupted suture was utilized, whereas in the second group a combination between fewer sutures and tissue adhesive was used. The anastomotic time, total operative time, blood flow velocity before, immediately after and 48 hours after the procedure, as well as an independent grading of the anastomosis immediately after the procedure were performed. Magnetic resonance imaging (MRI) was performed in order to assess the degree of stenosis. After euthanasia, histology and scanning electron microscopy (SEM) were performed on the vessels in order to assess possible complications. Results: A total of 24 anastomoses were performed, of which 12 with a classic technique and 12 with an adhesive technique. All the anastomoses were patent with a significant reduction of anastomotic and total operative time. The grading of the anastomoses showed better results in the classic suture group. The blood flow velocities were not statistically significant between the 2 groups. On MRI there was one stenotic anastomosis, whereas histology and SEM showed more complications on the adhesive group. Conclusion: Anastomotic times were significantly lower with a non-significant trend toward more thrombotic complications in the adhesive group. Further improvement of the glue properties and refinement of the technique will likely make it a viable alternative to interrupted suturing in the future.