Category: Nephrology and Dialysis · Hemodialysis
First Hemodialysis Through a Neck Catheter, but the Peritoneal Dialysis Catheter Is Still In: Why Doctors Wait, How Much Online HDF Helps the Heart, and Planning Permanent Access
AI Overview / Quick Answer (BLUF)
After switching from peritoneal dialysis to hemodialysis, doctors often keep the abdominal catheter briefly until the neck catheter works reliably, as a backup, and until surgery can remove its cuffs, unless peritonitis is refractory or fungal. High-volume online HDF lowered all-cause mortality about 23%.
patients and families who have just switched from peritoneal dialysis (CAPD) to hemodialysis through a neck catheter — why the abdominal catheter is still in, when it should come out quickly, online HDF evidence for heart patients, reducing blood pressure drops during dialysis, and preparing permanent access.
Fungal peritonitis? Read
fungal peritonitis on peritoneal dialysis ·
Red flags ·
Transition steps table ·
Dialysis comparison table ·
Access table ·
FAQ
From a kidney patient family: Dad has heart disease, just had his first hemodialysis through a neck catheter, and it is the second night — why is the abdominal catheter still in?
Direct answer: keeping the abdominal catheter in during the first days of hemodialysis is common and usually has a medical reason, but families have every right to ask the doctor directly what the reason is for this patient and when removal is planned, especially if the switch was caused by an abdominal infection.
The son of a patient in a kidney patient group wrote: “Dad also has heart disease. He just had his first dialysis through a neck catheter, but the hospital has not removed the abdominal dialysis catheter yet, and I am not sure why. I read that online dialysis reduces the load on the heart, and I would like Dad to have that.”
Changing kidney treatment raises many questions for families. This article summarizes the research to help you talk with the care team more precisely.
Red flags: tell the nurse now, or call emergency services if at home
Direct answer: while both the neck and abdominal catheters are in place, these symptoms need urgent care.
Urgent now
- Chest pain or pressure, breathlessness, unable to lie flat, palpitations or an irregular heartbeat
- Feeling faint, confusion, or drowsiness during or after dialysis
- Bleeding from the neck catheter that will not stop, or a displaced catheter — press on the site and call for help
- Fever or chills, especially when dialysis starts — possible catheter bloodstream infection
- Sudden swelling of the face, neck, or arm on the catheter side — possible vein clot
Symptoms from the abdominal catheter still in place
- Abdominal pain, fever, or cloudy fluid — possible peritonitis
- A red, swollen, painful, or pus-draining exit site
1. Why doctors do not remove the abdominal catheter right after starting neck-catheter hemodialysis
Direct answer: there are three main reasons — confirming the neck catheter works, keeping a backup, and waiting for surgical removal that must take out the cuffs completely. But if the switch was caused by refractory or fungal peritonitis, international guidance recommends prompt removal.
Reason 1: making sure the neck catheter works well
A temporary neck catheter can clot, deliver too little blood flow, or need repositioning early on. Doctors usually watch several sessions for good flow, stable blood pressure, and tolerance before giving up the other option.
Reason 2: a backup, or a possible return to peritoneal dialysis
If the neck catheter fails, the abdominal catheter still allows dialysis while it is fixed. And if the reason for switching is temporary, such as a hernia, a fluid leak, or recent abdominal surgery, some people can return to peritoneal dialysis, so doctors may not rush removal.
Reason 3: removal is surgery that must take out the cuffs completely
A Tenckhoff catheter has fabric cuffs that tissue grows into under the skin, so removal is done in an operating or sterile procedure room.
A follow-up of 278 patients who left peritoneal dialysis (1990)
found later complications after removal in 4.3%, mostly abscesses at the old catheter site and some retained cuffs, occurring on average about 541 days after removal.
Scheduling the operating room and spacing removal from the anticoagulant used during dialysis are reasons for the wait.
the ISPD 2022 guideline
recommends removal for refractory peritonitis, meaning the fluid is still cloudy after 5 days of appropriate antibiotics, and immediate removal once fungi are found.
If your father switched to hemodialysis because of an abdominal infection, ask the doctor whether this applies.
Typical steps when switching from peritoneal dialysis to hemodialysis (cards on mobile)
| Step | What doctors assess | Patient care | Typical timing |
|---|---|---|---|
| Neck dialysis catheter placed | Catheter position, bleeding, chest X-ray | Keep the dressing dry; never pull or open the caps | Day one |
| First hemodialysis sessions | Adequate flow, blood pressure and symptoms during dialysis | Shorter sessions with less fluid removal at first; report symptoms immediately | Several sessions in the first week |
| Decision on the abdominal catheter | Reason for switching, permanent or temporary, any refractory or fungal infection | Care for the exit site as taught; no exchanges unless ordered | Refractory or fungal infection: remove promptly / Otherwise: per the doctor’s plan |
| Surgical catheter removal | Operating-room slot, clotting tests, timing relative to dialysis | Watch the wound; look out for fever or pus long-term | Per surgical schedule |
| Permanent access preparation | Arm vessels, heart disease, long-term plan | Protect the planned access arm; no blood draws or IV lines on that side | AVF ready in about 6–12 weeks / AVG about 2–4 weeks |
2. How much online HDF helps the heart: evidence and limits
Direct answer: online HDF adds convective clearance using ultrapure replacement fluid the machine makes during treatment. The strongest evidence is for high-volume online HDF, which lowered overall and cardiac mortality, but it depends on access with strong blood flow.
Effect on mortality
The CONVINCE trial (2023)
randomized 1,360 patients with a mean convection volume of 25.3 liters per session; 17.3% died in the HDF group versus 21.9% with standard hemodialysis (HR 0.77).
A pooled analysis of 2,793 patients (2016)
found 14% lower overall mortality and 23% lower cardiovascular mortality, with the greatest benefit above 23 liters per session.
And a cause-specific analysis (2017)
found the reduction came mainly from fewer cardiac deaths.
Limits to know
The ESHOL trial (2013)
of 906 patients lowered overall mortality by 30%, but the effect on cardiovascular mortality (HR 0.67) did not reach statistical significance.
The Cochrane review (2015)
found convective dialysis lowered cardiovascular mortality (RR 0.75) but the effect on overall mortality was unclear (RR 0.87), and most studies involved patients who already had adequate access.
A temporary neck catheter may not deliver enough flow for high convection volume, and availability depends on the unit and your coverage.
How urgent are the kidney patient’s symptoms at home, and when not to wait?
Get a severity check and personalized guidance from our Advisory team — the assessment helps you see how closely symptoms match kidney-care warning signs, which band they fall in, and when to see a doctor soon. Use it alongside the red-flag section above; it does not diagnose any disease.
3. Reducing blood pressure drops during dialysis in heart patients
Direct answer: a blood pressure drop during dialysis briefly reduces blood flow to the heart. Online HDF reduces it partly, but measures that work with any method are limiting weight gain between sessions, adjusting blood pressure medicines, and adjusting dialysate temperature.
Locatelli’s randomized trial (2010)
of 146 patients found sessions with symptomatic hypotension fell from 10.6% to 5.2% with HDF, while standard hemodialysis rose from 7.1% to 7.9%.
Cochrane found about 28% lower risk of hypotension during dialysis (RR 0.72).
And a 2025 meta-analysis
notes that guidelines recommend a dialysate temperature of 35.0–35.5 °C instead of 36.5–37.0 °C to reduce intradialytic hypotension.
- Limit salt and fluid between sessions so less fluid has to be removed quickly in one session
- Ask whether blood pressure medicine should be delayed before dialysis; never skip it on your own
- Tell the nurse at once about yawning, cramps, dizziness, blurred vision, or chest tightness
- Have the nephrologist and cardiologist plan together, including scheduled echocardiograms
Comparison of dialysis methods and blood pressure measures for kidney patients with heart disease (cards on mobile)
| Method | Mechanism | Evidence | Limits |
|---|---|---|---|
| Standard hemodialysis (high-flux HD) | Removes small molecules by diffusion across the filter | The comparator in all trials | Removes fewer middle molecules |
| High-volume online HDF | Adds convection with ultrapure replacement fluid; removes more middle molecules | CONVINCE 23% lower overall mortality / pooled 4 trials 23% lower cardiovascular mortality | Needs more than 23 liters convection and strong blood flow; depends on the unit |
| Cooler dialysate | Better vessel constriction, steadier blood pressure | Guidelines recommend 35.0–35.5 °C to reduce hypotension | Some feel cold; adjusted to tolerance |
| Limiting weight gain between sessions | Less fluid to remove per session | Core dialysis unit care principle | Requires salt control, not just fluid restriction |
| Longer or more frequent sessions | Slower fluid removal per hour | Used for patients with frequent hypotension | More time at the unit; depends on slots and coverage |
| Returning to peritoneal dialysis (if suitable) | Slow, continuous fluid removal through the day | An option when the reason for switching was temporary | Not possible if the peritoneum is damaged or severely infected |
4. Neck catheter care and planning permanent access (AVF/AVG)
Direct answer: a non-tunneled neck catheter is for short-term use. If hemodialysis will continue, plan permanent access soon — it carries less infection risk than a catheter and gives enough flow for high-volume online HDF.
The KDOQI 2019 vascular access guideline
recommends choosing access according to each patient’s life plan (ESKD Life-Plan), considering other conditions, vessels, and expected dialysis duration. People with severe heart failure should be assessed before choosing, because very high-flow access can add to the heart’s workload.
Types of dialysis access and considerations in heart patients (cards on mobile)
| Access type | Ready when | Infection risk | Heart considerations |
|---|---|---|---|
| Non-tunneled neck catheter | Immediately, for short-term use | Highest | Flow may be too low for high convection volume |
| Tunneled cuffed catheter | Immediately, while awaiting permanent access | Lower than non-tunneled, higher than arm access | Does not add cardiac workload |
| Arteriovenous graft (AVG) | About 2–4 weeks | Lower than catheters | Enough flow for HDF; doctor assesses cardiac load |
| Arteriovenous fistula (AVF) | About 6–12 weeks | Lowest | Suits long-term HDF; assess first if heart failure is severe |
Caring for the neck catheter meanwhile
- Keep the dressing completely dry; sponge-bathe or protect the site from water
- Reserve the catheter for dialysis only; never open the caps or touch the ends
- Protect the arm planned for permanent access; no blood draws or IV lines on that side
5. Questions families should ask the care team
Direct answer: precise questions get clearer answers and help the doctor understand what the family is worried about.
- Why did he switch to hemodialysis? Is it permanent or temporary? Is there a refractory or fungal infection?
- When is abdominal catheter removal planned, and how should it be cared for meanwhile?
- What type of neck catheter is it, how long can it stay, and what permanent access is planned and when?
- Does the unit offer online HDF, does our coverage include it, and should it start once permanent access is in place?
- Is the cardiologist aware of the dialysis plan, and how should heart or blood pressure medicines be adjusted on dialysis days?
Ask politely and write down the answers. If they are still unclear, ask to speak with the attending physician or the dialysis unit nurse again.
Frequently asked questions (FAQ)
Questions families often ask when switching from peritoneal dialysis to hemodialysis
After the first hemodialysis through a neck catheter, why has the peritoneal dialysis catheter not been removed?
Common reasons are that doctors want to see the neck catheter work well, with adequate blood flow and stable blood pressure, over several sessions first; they keep the abdominal catheter as a backup in case the neck catheter clots or gets infected, or in case the patient can return to peritoneal dialysis if the reason for switching is temporary; and removal is minor surgery that must take out the catheter cuffs completely, so it needs an operating-room slot. Families can ask the doctor directly what the reason is for this patient and when removal is planned.
When should the peritoneal dialysis catheter come out quickly rather than wait?
The 2022 International Society for Peritoneal Dialysis (ISPD) guideline recommends removal for refractory peritonitis, meaning the fluid is still cloudy after 5 days of appropriate antibiotics, and immediate removal once fungi are identified. If the switch to hemodialysis was due to an abdominal infection, ask the doctor whether this applies, and report fever, abdominal pain, or pus at the exit site right away.
Does online HDF really reduce strain on the heart and lower mortality?
There is evidence that it helps, but the benefit depends on convection volume. The CONVINCE trial of 1,360 patients found that high-volume online HDF lowered all-cause mortality by about 23% compared with standard hemodialysis, and a pooled analysis of 2,793 patients found cardiovascular mortality 23% lower. The benefit was clearest above 23 liters per session, which requires vascular access with strong blood flow.
Does online HDF prevent blood pressure drops during dialysis?
Partly. In Locatelli’s randomized trial, the share of sessions with symptomatic hypotension fell from 10.6% to 5.2% with HDF, and the Cochrane review found about 28% lower risk of hypotension during dialysis. It still needs to be combined with limiting weight gain between sessions, adjusting blood pressure medicine timing, and adjusting dialysate temperature as the doctor sees fit.
Which dialysis method suits a kidney patient who also has heart disease?
No single method suits everyone. The nephrologist looks at the type and severity of heart disease, blood pressure during dialysis, the available access, and what the unit offers. High-volume online HDF is a well-supported option when available; longer or more frequent sessions allow slower fluid removal; and some people can return to peritoneal dialysis, which removes fluid slowly and continuously. The nephrologist and cardiologist should plan together.
Can we simply request online HDF?
You can ask, but it depends on whether the unit has the machines and ultrapure water system, whether your coverage includes it, and whether the access delivers enough blood flow. Most studies were done in patients who already had good access. A temporary neck catheter may not deliver enough flow for high convection volume, so the benefit is usually clearer once a permanent arm access is in place.
How long can a neck dialysis catheter be used, and when should permanent access be made?
A non-tunneled neck catheter is for short-term use. If hemodialysis will continue, doctors usually switch to a tunneled cuffed catheter and plan permanent access soon. An arteriovenous fistula (AVF) made from the patient’s own vessels usually takes about 6–12 weeks to be ready, while a graft (AVG) can often be used within 2–4 weeks. The KDOQI 2019 guideline recommends choosing the access type according to each patient’s life plan and other conditions.
How should both the neck catheter and the abdominal catheter be cared for in the meantime?
Keep the neck catheter dressing completely dry, never open the caps or touch the ends, and reserve it for dialysis only. Care for the abdominal catheter exit site as the peritoneal dialysis unit taught you, and do not use it for exchanges unless the doctor says so. Report fever, chills during dialysis, bleeding at the neck, a displaced catheter, abdominal pain, or pus at either site right away.
Scientific mechanism in brief
Summary by Asst. Prof. Dr. Norawit Raatpiboon:
standard hemodialysis removes waste by diffusion, which works well for small molecules such as urea but clears middle molecules such as beta-2 microglobulin and inflammatory mediators only to a limited extent.
Online HDF adds convection by pulling a large volume of plasma water across the filter and replacing it with ultrapure fluid the machine produces from dialysate during treatment, so more middle molecules are carried out.
This approach also cools the blood slightly through the replacement fluid, improves vessel constriction, and keeps sodium balance steadier, so blood pressure falls less, reducing repeated episodes of temporary heart-muscle ischemia during dialysis (myocardial stunning).
The benefit depends on convection volume, which scales with blood flow through the machine, so access with strong flow is a key condition.
A Tenckhoff catheter has fabric cuffs that tissue grows into to block infection and prevent displacement, so removal must dissect the cuffs out completely in an operating room; otherwise a retained cuff can later become a focus for abscess.
Academic references (E-E-A-T)
- Li PK, et al. ISPD peritonitis guideline recommendations: 2022 update on prevention and treatment. Perit Dial Int 2022.
- Complications of Tenckhoff catheters post removal. ASAIO Trans 1990.
- Blankestijn PJ, et al. Effect of Hemodiafiltration or Hemodialysis on Mortality in Kidney Failure (CONVINCE). N Engl J Med 2023.
- Maduell F, et al. High-efficiency postdilution online hemodiafiltration reduces all-cause mortality in hemodialysis patients (ESHOL). J Am Soc Nephrol 2013.
- Peters SA, et al. Haemodiafiltration and mortality in end-stage kidney disease patients: a pooled individual participant data analysis from four randomized controlled trials. Nephrol Dial Transplant 2016.
- Nubé MJ, et al. Mortality reduction by post-dilution online-haemodiafiltration: a cause-specific analysis. Nephrol Dial Transplant 2017.
- Locatelli F, et al. Hemofiltration and hemodiafiltration reduce intradialytic hypotension in ESRD. J Am Soc Nephrol 2010.
- Nistor I, et al. Haemodiafiltration, haemofiltration and haemodialysis for end-stage kidney disease. Cochrane Database Syst Rev 2015.
- Clinical Outcomes of Patients undergoing Hemodialysis with Cool versus Standard Dialysate: A Systematic Review and Meta-Analysis. Am J Nephrol 2025.
- Lok CE, et al. KDOQI Clinical Practice Guideline for Vascular Access: 2019 Update. Am J Kidney Dis 2020.
Compiled and reviewed by Asst. Prof. Dr. Norawit Raatpiboon · Generic drug names only; no trade names.
Medical disclaimer
This article is general education based on research. It is not a diagnosis and does not replace the decisions of the attending physician, who has the full picture of the patient. The timing of catheter removal, the dialysis method, and the right access depend on the reason for switching, heart disease, and what each hospital offers. Do not adjust or stop medicines yourself. If any symptom in the red-flag section appears, tell the nurse immediately or call emergency services.