The Double Stitch Everting Technique in the End-to-Side Microvascular Anastomosis: Validation of the Technique Using a Randomized N-of-1 Trial

Abstract

Background The double stitch everting (DSE) technique, in which time is won by leaving the needle inside the vessel wall in-between stitching, is a modification of the end-to-side (ETS) anastomosis in the interest of reducing anastomosis time. This ensures proper wall eversion, intima-to-intima contact, and improved suture symmetry. Materials and Methods We designed an N-of-1 randomized trial with each microsurgeon as their own control. We included 10 microsurgeons of different levels of experience who were then asked to perform classic and DSE ETS anastomoses on the chicken leg and rat femoral models. Every anastomosis was cut and evaluated using blinded assessment. Two-way analysis of variance (ANOVA) and multivariable logistic regression were used to analyze the results and for confounder adjustment. Results A total of 210 anastomoses were performed, of which 177 on the chicken leg and 43 on the rat femoral artery and vein. From the 210 anastomoses, 111 were performed using the classic technique and 99 using the DSE technique. The mean anastomosis time was 28.8 ± 11.3 minutes in the classic group and 24.6 ± 12 minutes in the DSE group (p < 0.001, t-test). There was a significant reduction (p < 0.001, two-way ANOVA) in the number of mistakes when using the DSE technique (mean 5.5 ± 2.6) compared with those using the classic technique (mean 7.7 ± 3.4). Conclusion The DSE technique for ETS anastomoses improves anastomoses times in experienced and moderately experienced microsurgeons while also improving or maintaining suture symmetry and lowering the number of mistakes.

Reduction of the Number of Live Animals Used for Microsurgical Skill Acquisition: An Experimental Randomized Noninferiority Trial

“…Although several studies demonstrated that the additional time spent exercising on nonliving tissue models improves the acquisition of technical skills in microsurgery, [3][4][5] working on living tissue models remained an important aspect. 2 Additional studies were necessary to explore the relationship between training and the number of live animals used.…”

“…We based the training regimen on our experience of 30 years in microsurgical training and microsurgical skill acquisition. 3 According to the availability of each student, there was a minimum of one meeting/week (working weeks). The consecutive order of the training program was followed regardless of the number of weeks missed as a result of holidays.…”

“…We based the training regimen on our experience of 30 years in microsurgical training and microsurgical skill acquisition. 3…”

“…Training on live animals, in particular on live rats, is an essential part of microsurgical skill acquisition. [1][2][3][4][5][6] For the past several decades, microsurgical training hinged on sacrificing a vast number of live rats. Recently, developments in animal welfare and European law have reinforced "the 3 R's of animal experimentation"-Replacing, Reducing, and Refining the use of animals in experiments.…”

Comment on “A modified ‘interrupted’ method with resting of the suture needle on the vessel wall for microvascular anastomosis”

“…We recently validated the double stitch everting technique in a randomized N-of-1 trial and are happy to report that the improvement in both speed and end-result of microvascular anastomoses is considerable (Dindelegan et al, 2020). Publishing new tricks in microvascular anastomoses is important, but validating these in well-designed studies is critical.…”