Paracentesis
Paracentesis is performed for diagnostic or therapeutic drainage of ascites. Similarly to thoracentesis, there are no absolute contraindications to thoracentesis. Patients with thrombocytopenia (< 50k) or other bleeding risk should be discussed with hematology for consideration of pretreatment with FFP. If there is significant bowel distention, decompression with NG tube may be indicated, though paracentesis can still be safely performed under US guidance.
Although dullness to percussion is commonly used to determine optimal site of needle insertion, US should be utilized for this purpose if available. As with thoracentesis, it is not necessary to perform the entirety of the procedure under US guidance.
Complications
- The most common complication of paracentesis is persistent fluid leak. This can be mitigated by use of Z-track during needle insertion, and typically resolves over several days.
- Although serious complications are rare, perforation of vessels can cause serious bleeding.
- Infection of the ascetic fluid is possible though rarely occurs unless there is bowel perforation. If bowel is perforated, patient is monitored and treated for infection if it develops.
Technique
- Position patient in supine position.
- Using ultrasound with phased array (cardiac) probe, determine where the deepest fluid pocket is in either the RLQ or LLQ abdomen.
- Prep skin with chlorhexidine or povidone-iodine and patient is sterilely draped.
- Inject a small amount of lidocaine at point of entry and injected until at the level of the peritoneum.
- Attach a 3 way stopcock and syringe to the paracentesis needle.
- Insert the paracentesis needle slowly while pulling back on the syringe, using the Z-track method.
- Once fluid is obtained, keep the needle in place and push the catheter over the needle and into the abdominal cavity.
- Drain as much fluid as necessary, then remove drain and cover with dressing.
- Send fluid for appropriate testing- - most of which is the same as for thoracentesis and is available under the ‘ED Thoracentesis’ order set.
The administration of albumin following paracentesis is controversial as there is no demonstrated survival benefit to administration. It is generally accepted that up to 5 L of fluid may be removed without replacement of colloid. If greater than 5 L are removed, providers may consider giving 6-8 g/L of albumin (25% concentration).
Resources/References
- UCSD Standardized Procedure Peritoneal Paracentesis (Adult, Peds)
- Thomsen et al. Paracentesis. N Engl J Med 2006; 355:e21. DOI: 10.1056/NEJMvcm062234 (Video)
