Simulation
Description
The OB laceration lab should start with a review of the PowerPoint presentation to ensure that all learners have reviewed the anatomy, physiology, and steps of the repair. The OB laceration lab can be set up with four stations to include all levels of learners from medical student to senior resident. The four stations include the following:
- Needle handling and basic suturing
- Repair of the second degree laceration
- Repair of the obstetric anal sphincter injury, Sultan model
- Repair of the obstetric anal sphincter injury, porcine model
Once the didactics have been reviewed, the learners should rotate through all level-appropriate stations.
The low-fidelity trainer for the second-degree laceration is the Perineal Laceration model from Nasco. It allows for the learner to identify the second-degree laceration.
Residents can then practice the steps of a simple second degree repair including placing an initial suture above the apex, reapproximating the vaginal laceration and the perineal body, and completing a subcuticular stitch. The two high fidelity models are described below with advantages and disadvantages listed.
Materials
The following is a list that accommodates supplies for 10 active learners (three of whom are novice — either medical students or PGY1) at one time. More stations can be set up based on the institution's needs. Of note, many instruments and suture could be borrowed from the clinical setting as well.
- Obstetric laceration repair — first and second degree perineal models
Item Cost Obstetrical laceration models (3)
Each perineal model can be used for about 10 repairs - five on either side$187/model; $100/refill Needle drivers (3) In instrument kit with model Forceps (3) In instrument kit with model Suture scissors (3) In instrument kit with model Suture (varying sizes) Nonsterile gloves Sharps container - Sultan Trainer
Item Cost Sultan trainer
Each perineum can be used for approximately eight repairs - four on either side$1,006/trainer kit Sultan replacement block $170/perineal refill Needle driver (1) Forceps (1) Suture scissors (1) Suture (varying sizes) - Pig prosections
Item Cost Absorbent pads (3) $90/prosection Pig prosections (3)
Prosection cost will vary. Price estimate from a university animal lab.Suture (varying sizes) Needle drivers (3) Forceps (3) Suture scissors (3) - Needle handling, knot tying
Item Cost Suture mats (surgical towels can also be used) $32/mat Suture (larger sizes) Needle drivers Forceps Suture scissors
Preparation
In a conference room, or similar space, set up each station. Room should have adequate seating, chairs and tables, and be well lit.
For the suturing and knot tying station, suture mats (or blue towels) should be placed one per chair; one learner for each mat. Each mat should have a needle driver, forceps, and suture scissors. Larger suture should be available for each learner to practice. We also recommend having nylon or silk available for novice learners to practice knot tying. One facilitator should be at this station during the hands-on portion. This can be either a faculty member or an upper level resident.
For the second-degree laceration station, secure a perineal model in front of each chair. One learner per perineal model. A needle driver, forceps, and suture scissors should be available for each model. A laceration should be made in each model before the lab congruent with a second-degree laceration. Various suture should be made available to allow for the learner to choose the size and type of suture to better understand appropriate suture selection. One faculty member should be present at this station during hands-on portion.
For the Sultan trainer, a fourth-degree laceration should be created in the perineal block before the lab. Two learners should be at the model; one doing the primary repair, and one assisting (tying knots, cutting suture, retracting). A needle driver, forceps, and scissors should be available. Various types of suture also should be available to help the learner understand which suture is suitable for each step. A faculty member should be present at this station during the hands-on portion.
For the pig prosections, contact either an animal lab that conducts porcine surgical labs or local slaughterhouse. The specimen needed is the perineum of the pig which can be dissected away from the undersurface of the tail. If the pig prosection is to be included, each prosection should be set up on an absorbent pad. A fourth-degree laceration can be created in each prosection. A needle driver, forceps, and suture scissors should be available at each prosection with a variety of suture types. A second-degree laceration cannot be repaired with this model because of the anatomy of a pig. See also tutorial, repair of 4th degree perineal tear, pig model at https://www.youtube.com/watch?v=II4zIQQj2Og. Each station can accommodate one primary learner and one assistant (to tie suture, cut suture, and retract). One faculty member should be present at this station during the hands-on portion.
- Set up time: The lab can be set up with eight stations as described in approximately 30-45 minutes by two facilitators.
- Lab time: The hands-on portion of the lab should last approximately 2 hours to accommodate 20 learners with additional time as needed for a review of the didactic material and/or for larger groups.
High Fidelity
There are a variety of high fidelity models that exist for this training model. In regards to synthetic models, we describe the Sultan Anal Sphincter Trainer from Limbs and Things. http://limbsandthings.com/us/products/sultan-anal-sphincter-trainer
An advantage of this trainer is that it provides a clear depiction of the anatomy to allow learners to practice each step of the repair. Further, it is reusable for at least eight repairs as the insert can be flipped over and used for more repairs. The disadvantage to this model, and all synthetic models like it, is cost. In researching the models, most cost about $1,000 and require ongoing cost ($100-$300) for replacement parts.
The other high fidelity model option is that of cadaveric models — particularly porcine. The advantage is that this model demonstrates the fragility of working with tissue during a repair. It also forces the learner to identify structures when they are not easily color-coded as with the synthetic models. The disadvantages are twofold: first, it can be more difficult to find a location from which to purchase prosections, and second, the models can only be reused in one lab setting, thus requiring a purchase before each lab.
Links to other models mentioned:
- Suture pads: https://www.3-dmed.com/product/soft-tissue-suture-pad
- Perineal models (low fidelity): https://www.enasco.com/product/LF01044U
Assessment Tools
Two tools can be used for assessment. First, Resnick’s objective structured assessment of technical skills (OSATS) can help assess general surgical principles. Second, the task-specific evaluation checklist (part 5 of this unit) can assess steps of a standard second-degree laceration repair.
The CREOG Surgical Skills Task Force created this simulation as part of a standardized surgical skills curriculum for use in training residents in obstetrics and gynecology.