Departments of Gynecology and Obstetrics (Dr. Romeo), University of Torino, Torino, Italy; Project Leader REC Research Educational Centre Department of Gynecology and Obstetrics University of Torino (Dr. Romeo), Torino, Italy.
University of São Paulo (Dr. Fernandes), Sao Paulo, Brazil.
J Minim Invasive Gynecol. 2020 Sep-Oct;27(6):1395-1404. doi: 10.1016/j.jmig.2019.09.782. Epub 2019 Sep 20.
To investigate why security of identical knot sequences is variable and how to avoid occasionally insecure knots.
A factorial design was used to assess factors affecting the security of half knot (H) and half-hitch (S) knot combinations. The effect of tying forces and the risk factors to transform H knots into S knots were investigated. The risk factors evaluated were as follows: starting with an H1 or H2 instead of an H3 knot, inexperience, short sutures, and monomanual knot tying. Security of transformed knots, S2S1 and S2S2 knots, and their recuperation with 2 additional half hitches, SSb or SbSb, were evaluated.
Training center for laparoscopic suturing.
Not applicable.
Security of knots was evaluated in vitro.
The forces that caused knot combinations to open before breaking of the suture were used to calculate the risk of opening with low forces. Tying more strongly increased the security of half knots (H2H1sH1s) (p <.02) and half hitches (p <.001). The forces needed to transform an H3 into an S3 are higher than those for an H2 (p <.001), and the risk increases when the surgeon is inexperienced (p <.001), when sutures are short (p <.001), and when monomanual knot tying (p <.001) is used. Inadvertently made S2S1 and S2S2 knots are dangerous, with the exception of the symmetric S2S2, which is stable. Unstable knots such as S2S1a and S2S2a knot combinations improve with 2 additional blocking half hitches (SbSb), but S2S2aSbSb remains occasionally insecure.
To reduce the risk of accidentally transforming a first H into an S knot, it is recommended to start with an H3, tie with force, avoid short sutures, and use bimanual suturing. This permits the recommendation to use preferentially H3H2 knots or 5 half hitches (SSSbSbSb). When in doubt, half knot combinations should be secured with at least 2 blocking half hitches.
探讨相同结序列的安全性为何存在差异，以及如何避免偶尔出现不安全的结。
采用析因设计评估影响半结（H）和半结（S）结组合安全性的因素。研究了打结力的影响以及将 H 结转变为 S 结的危险因素。评估的危险因素如下：从 H1 或 H2 开始而不是 H3 结，缺乏经验，缝线短，单手打结。评估转变后的结，S2S1 和 S2S2 结，以及用另外两个半结，SSb 或 SbSb 进行恢复。
腹腔镜缝合培训中心。
不适用。
在体外评估结的安全性。
用于计算低力打开结组合的力来计算低力打开的风险。更强的打结会增加半结（H2H1sH1s）的安全性（p <.02）和半结（p <.001）。将 H3 转变为 S3 所需的力高于 H2（p <.001），当外科医生缺乏经验（p <.001）、缝线较短（p <.001）以及单手打结（p <.001）时，风险会增加。无意中形成的 S2S1 和 S2S2 结是危险的，除了对称的 S2S2 结是稳定的。不稳定的结，如 S2S1a 和 S2S2a 结组合，用另外两个阻塞半结（SbSb）改善，但 S2S2aSbSb 偶尔仍不安全。
为了降低意外将第一个 H 转变为 S 结的风险，建议从 H3 开始，用力打结，避免缝线短，并使用双手缝合。这允许建议优先使用 H3H2 结或 5 个半结（SSSbSbSb）。如有疑问，半结组合应至少用 2 个阻塞半结固定。
