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.

May Case #1: Abdominal Pain- Discussion

This patient has splenomegaly due to hyperviscosity syndrome.  She had a relapse of her leukemia and developed tumor lysis syndrome due to her overwhelming tumor burden while in the hospital.  She was noted initially to be anemic and thrombocytopenic and later required transfusions of both PRBCs and platelets. 

Splenomegaly

On ultrasound, splenomegaly is defined as a longitudinated measurement of the spleen greater than 13 cm (in adults). 

Although it is not a disease state itself, it is usually a response to underlying pathology.  Causes of splenomegaly include:

• neoplasm or myeloproliferative disorders (lymphomas, leukemias, metastatic disease)
• infectious processes (TB, EBV, CMV, HIV, Lyme disease, RMSF)
• portal hypertension or systemic congestion (CHF, cirrhosis)
• chronic transfusion

Hypersplenism is indiscriminate destruction of the formed elements of the blood by an enlarged spleen.  Any blood line can be affected (erythrocytes, neutrophiles or platelets) alone or in combination.  Splenic hypertrophy leads to premature destruction of cells by splenic macrophages, an exaggeration of the spleen's normal function of removing senescent cells.  Splenectomy may correct cytopenia.

May Case #1: Abdominal Pain

40 y/o AAF presents with c/o abdominal pain, constipation and occasional vomiting over approximately 1-2 days.  She also c/o generalized weakness and occasional headaches with blurry vision.
PMHx:  Leukemia (last chemo about 2 months prior), chronic pain syndrome, depression
Meds:  oxycontin, lortab, stool softener
SocHx:  denies tobacco or ETOH
FamHx:  HTN, DM
All: NKDA

PE: BP 110/62, P 89, R 20, T 99, POx 99%
GEN: WNWD, AAF, moderate distress
CHEST:  CTA B, non labored
CV:  RRR, no M/R/G
ABD:  distended, fullness in L hemi-abdomen with diffuse TTP, no rebound or guarding, +BS
EXT:  no C/C/E
SKIN:  no rashes noted

Bedside ultrasound is performed:

 

What is the abnormality visualized here?
What is the diagnosis?

Special thanks to Dr. Erin McBride for this case write up!

January Case #3: Abdominal Pain-Discussion

The patient has appendicitis with a fecolith visualized in the appendiceal lumen. He under went a laproscopic removal of his appendix and was discharged home in 2 days.

Appendicitis

Using ultrasound to diagnose appendicitis is not a new technique, having first appeared in the literature in 1986. Multiple studies have illustrated the benefits of graded compression ultrasound to diagnose appendictis, with sensitivities ranging from 89-95% and specificitites of 95-100%. In this technique, the sonologist uses a linear high freqency transducer to apply a constant pressure to the right lower quadrant. Bowel loops will normally compress or become displaced from view when pressure is applied. In the case of appendicitis, the appendix is inflamed and non-compressible. It appears as a blind ended tubular pouch, which lacks peristalsis and compressibility. It should measure >6mm in diameter and may contain a fecolith, which will appear as a hyperechoic structure in the lumen with distal shadowing. Other signs that confirm appendicitis are an increase in the brightness or echogenicity of the periappendiceal fat. When color flow is applied to the acutely inflamed appendix, there may be a increased amount of flow in the wall circumferentially.

The easiest way to perform graded compression ultrasound to diagnose appendicitis is to have the patient localize their maximal point of pain with 1 finger. This has been shown to increase the ability to find the appendix and also can reduce exam time. Using a constant pressure to displace overlying bowel, the RLQ should be interrogated in both longitudinal and transverse planes. The appendix is easiest to identify in the transverse plane, appearing as a target with multiple layers of echogenicity, corresponding to the different layers within the bowel wall.
Once it has been identified, it should be examined in both planes. Attempts at compressibility should be made- if the appendix compresses or "winks" at you, then it is unlikely to be appendicitis. In appendicitis, the appendix may be displaced posteriorly, but the walls should not compress. Measurements of the diameter should be taken and color flow may also be placed on the appendix to denoted an increase in color flow (http://www.radiologyworld.com/appendicitis.gif). Interrogate the entire appendix before making your final diagnosis to ensure that you are not missing a fecolith or fluid collection that may indicate and abscess.


Puylaert JB. Acute appendicitis: US evaluation using graded compression. Radiology. 1986; 158(2):355 -60

January Case #3: Abdominal Pain

25 y/o WM presents to the ED with complaints of periumbilical abdominal pain for 2 days, which is now moved to his RLQ. He denies N/V, F/C.

PMHx: Asthma
PSHx: none
Meds: none
Allergies: NKDA
Soc Hx: denies ETOH, drugs or tobacco

PE:
VS: BP 125/70, P 90, R 18, T 98.5
GEN: WNWD, WM, NAD
CHEST: CTA B, nonlabored
CV: RRR, no M/R/G
ABD: TTP RLQ, garding, no rebound, +BS, guiac-
EXT: no C/C/E

Bedside ultrasound is performed:


What is the diagnosis?

What is the hyperechoic structure within the lumen?


Special thanks to Ruben Font for submitting this case!