Thread by @bourneauguste

1/14
⚡Thread ONE of TWO on troubleshooting PD catheter complications
🗣“Catheter isn’t working, time to switch to hemodialysis”
🗣 “PD catheters can be so frustrating”
Have you heard these 🗣 before?
You are not alone!
#NephTwitter #tweetorial
Got⬇️flow on PD, what's next?

2/14
🔥Maintaining peritoneal access is a lifeline for PD patients

⚡Up to 20% of PD transfers to HD are from catheter complications pubmed.ncbi.nlm.nih.gov/12322816/

⚡Prompt management of catheter complications may prolong patient survival on this modality

3/14

There are 2⃣ types of flow failures:
📌Inflow
📌Outflow

They may occur independently or at the same time ➡️⬅️

In this #tweetorial we will be focusing on the most commonly encountered flow problem in PD, outflow failure

4/14
🤔What is outflow failure?
👉Incomplete recovery of instilled dialysate
👉Reabsorption, pericatheter or dialysate leakage have been ruled out
👉Dialysate reabsorption can occur with low osmotic solutions (eg. 1.5%) after a long dwell (> 6 hours)

5/14
🤔How common is outflow failure?

⚡Occurs in up to 20% of patients but depends also on catheter insertion method
👉Percutaneous 10-22%
👉Laparoscopic 4-14%

pubmed.ncbi.nlm.nih.gov/20630641/

6/14
🤔What are the steps in assessing for outflow failure?

1⃣ Get clinical history
2⃣ Examine for hernias/ leaking near exit site
3⃣ If fluid seen then use a urine dipstick; will turn positive in presence of glucose, confirming a leak
4⃣ Get radiographic imaging

7/14
🤔What imaging do you get initially?

1⃣Start with an abdominal X-ray
✅Check catheter location
✅Check for fecal loading
✅Check for catheter kinks

Below you can see that catheter tip (red arrow) has migrated to RUQ, resulting in poor outflow.

8/14
🤔What if X-ray is normal & outflow problems persist, what next?
👉CT peritoneogram⭐️to look for a leak/encapsulated catheter
👉Esp if patients report difficulty breathing/groin swelling swelling
👉CT below shows left inguinal hernia (red arrow)➡️patent processus vaginalis

9/14
⭐️ Steps in CT peritoneogram
1️⃣ Mix 100mL of contrast with 2L of dialysate
2️⃣ Instill mixture into peritoneum
3️⃣ Ambulation for 2 hours to allow dye to disperse
4️⃣ Then get CT abdomen to find 🔎 contrast outside of peritoneal cavity

10/14

🔥Constipation is the most common cause of outflow obstruction but what’s the mechanism?

@NephroShah explains: renalfellow.org/2018/11/20/let…

📌Constipation➡️Colonic distention➡️Blocks catheter holes➡️Poor outflow

📌As fluid is drained, colon surrounds catheter & reducing flow

11/14
🤔How do I manage outflow failure in PD then?

1⃣ Depends on the underlying cause
2⃣ Some interventions may require surgical manipulation/removal of the catheter or pharmacotherapy with laxatives.

12/14

🤔Should constipation be managed with enemas in PD patients?

PO osmotic agents👍>>> Stimulant laxatives⚠️
⚡⚡Enemas → colon mucosal irritation → transmural bacterial migration → Peritonitis
(pubmed.ncbi.nlm.nih.gov/8863339/)

13/14
Conclusion :
📌20% of PD failure is due to catheter problems
📌Constipation = most common cause of⬇️outflow
📌Catheter migration, leaks, hernias & omental wraps =⬇️outflow
📌Use osmotic laxatives💊 first
⚠️Avoid enemas in PD patients⚠️

14/14
🏁This concludes Part I of catheter complications in PD
⚡Part II will be published within one week. Stay tuned!
💥This happens to be my first #tweetorial & many thanks to @NSMCInternship @captainchloride @amyaimei @drM_sudha & @Nephro_Sparks for the support!