High-rebound sponge as a simulation tool for perineal suture

Perineal traumas are common and sometimes unavoidable obstetric complications during vaginal childbirth.¹ One systematic review found that approximately 75% of all women who give birth vaginally will have lacerations of various levels of severity in the labia, vagina, and perineum.² The worldwide episiotomy rate for vaginal deliveries is estimated to be more than 50%.³ Perineal traumas can lead to complications during and after the healing process.⁴ Women who give birth vaginally with lacerations or episiotomy are at higher risk of postpartum pain, psychological trauma, and dyspareunia than women who give birth vaginally without lacerations or episiotomy.⁵ Some studies have demonstrated that suture techniques can reduce the risk of complications, including short- and long-term pain.^6,7

Perineal suture is an essential and technical skill to master for students and residents of obstetrics and gynecology and family medicine. This skill requires frequent practice to achieve mastery, but it is not possible or permissible to practise this on patients. Thus, simulation outside of the delivery room is an important component of surgical training. There are a variety of materials and models for simulating repair of the perineum including strips of meat, knitted polyethylene terephthalate (Dacron), polypropylene mesh, and silicone. Pork tissue is often used for suture practice because of its natural tissue properties, but it is not widely available and is costly. Knitted polyethylene terephthalate is readily available and commonly used for suture practice; however, it does not have the same properties as natural tissue. Currently, silicone is a frequently used material for models of perineal suture training. Although silicone does not hold a suture in the same manner as skin, it is thin, transparent, and flexible and can sufficiently emulate closure. However, the cost of silicone models is relatively high. Repeatedly practising stitching can cause damage to the silicone model and leave traces of stitching, thereby weakening the effectiveness of the practice.

Sponges have also been used for suturing practice due to their affordability, elasticity, and recyclability. A high-rebound sponge has excellent breathability, resilience, and durability. A perineal incision and suturing model using a high-rebound sponge block is simple to make, not easy to damage, and can be reused on each side. Bleeding can also be simulated by injecting prepared red liquid into the sponge. Students and residents can also independently create this model and practise perineal suturing repeatedly at home.

Technique

The following technique is recommended:

1. Begin with a high-rebound sponge. Cut a hole in the middle of the sponge (Figure 1A).

2. Cut a wound in the side with scissors (Figure 1B).

3. Prepare all necessary tools for suturing (Figure 2).

4. Perform layered suturing (Figure 3).

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Figure 1.

High-rebound sponge perineal suture model: A) Sponge cut into model of perineum. B) Wound cut on the side of the sponge.

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Figure 2.

Materials required to simulate perineal suture include a high-rebound sponge, forceps, a needle, a needle holder, scissors, and silk thread

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Figure 3.

Layered suturing: A) The bulbocavernosus muscle layer (arrow) during suturing. B) High-rebound sponge after suturing.

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