Paracentesis
Background:
Abdominal paracentesis is a common procedure done in the Emergency Department (ED) that must be mastered by EM residents and students. The purpose of a paracentesis is to remove accumulating ascites from the peritoneum. A diagnostic paracentesis is indicated in patients in which the ascites is new or to detect the presence of infection in patients with already known or suspected ascites. Therapeutic paracentesis is often conducted in the ED setting to relieve any cardiorespiratory and gastrointestinal manifestations of tense ascites. While this procedure has been described in modern medical literature for over a hundred years, the addition of ultrasound can enhance the safety of the procedure and can help detect as little as 100 ml of fluid.
This paracentesis simulator uses porcine skin with underlying muscle and fascia to replicate the feel of a real human undergoing this procedure. A gallon water jug is used to simulate the peritoneal cavity filled with ascites. Placing a small hand towel or sterile blue towel in the water jug acts as a wonderful mimic of bowel loops "floating" in the peritoneal fluid when ultrasound is used. A layer of ulrasound gel is placed liberally on one side of the water jug and then the pork belly is layered on top of that. This tissue is secured to the jug with 3M microfoam surgical tape (or other adhesive like duct tape). This model has a realistic feel and can be used with ultrasound to replicate intraperitoneal contents. The thickness of the plastic jug will give a realistic "pop" into the peritoneum with the paracentesis needle. In addition, this trainer can be used multiple times by different learners before being replaced. This model will allow the learner to conduct a realistic paracentesis procedure, while removing actual fluid.
Supplies:
1. 1 gallon jug of water ($1 from local grocery store)
2. Sterile blue towel or hand towel
3. Pork Belly with skin still attached, about a 15 cm x 15 cm piece ($5 from Asian market or local meat market)
4. Ultrasound and ultrasound gel (OPTIONAL)
5. Roll of 3M Microfoam Surgical tape (or duct tape, $3-4 from local hardware supply store)
6. Mannequin head and torso with blue surgical drapes (OPTIONAL)
7. Paracentesis kit
Instructions:
- Open gallon water jug and place blue sterile towel into the jug. May need to pour some of the water out so the towel does not displace the water inside and make a mess. Next, top off the jug by adding more water to completely fill it, to eliminate any air pockets that will interfere with the ultrasound images.
- If cap is not a screw-on type, then tape cap shut. Allow gravity to bring towel to bottom of water jug.
- Apply a liberal amount of ultrasound gel to one side of the water jug.
- Layer a piece of pork belly on top of the ultrasound gel.
- Secure piece of pork belly to water jug with 3M Microfoam Surgical tape or duct tape.
- Place the apparatus adjacent to a mannequin torso and secure with tape (optional). Then cover the apparatus with blue drapes for a more realistic effect.
- Simulation model is ready. Learner can use ultrasound to confirm presence of ascites and loops of intestines by placing curvilinear ultrasound probe on the pork belly.
- They can then use a paracentesis kit to practice drawing out peritoneal fluid. There will be a realistic feel to the needle insertion into actual skin and tissue and a realistic "pop" into the peritoneal cavity.
Paracentesis Publication in the Journal of Education and Teaching EM