Procedure: Paracentesis

A patient presents to the ED with complaints of gradually worsening shortness of breath and abdominal pain.  He admits to daily alcohol use and abdominal fullness.  You note that his abdomen is distended with a fluid wave and diffuse tenderness to palpation.  You are concerned about new onset ascites and spontaneous bacterial peritonitis.  So how do you tap his belly?

Paracentesis

If the patient has been tapped previously, then using the previous site is preferable.  Now in this instance, there is no previous site, so there are 2 preferred sites.  The first is the infraumbilical approach, which is located about 2 cm below the umbilicus.  The other choice is the lateral approach, 4-5 cm cranial and medial to the anterior superior iliac spine in the lower quadrants.  If using the infraumbilical approach, be sure to make sure the bladder is empty.

Now, ultrasound certainly makes positioning much easier.  Using a low frequency 3-5 MHz transducer, scan through the abdomen to find the largest pocket of fluid.  Now, without moving the patient, prep the area and sheath the probe with a sterile cover.  Now place the probe in a longitudinal plane (probe indicator to the pt's head) and find the largest pocket of fluid.  Insert the needle in alignment with the midline seam on the probe.  The needle is then advanced in real time through the abdominal wall, watching the needle (hyperechoic structure) enter the peritoneum on ultrasound.  By using this technique, you are able to stay away from bowel or when using the infraumbilical approach, bladder.


Ultrasound Guided Paracentesis from Jax Emergency Medicine on Vimeo.

Ski Lift

Ever had a problem placing an IJ under ultrasound guidance in a patient with a short neck?  So here is a little trick to get great visualization in the longitudinal or sagital plane.  I know what most of you are thinking, "Did you say long axis for IV placement?  That's really hard!" 

This technique is nicely descrbed by Jason Nomura in his blog and includes a video illustrating the technique.  Check it out!

Ski Lift Video