Chronic Hemodialysis Without Systemic Heparinization : a Randomized Study

Study Overview
=================
Brief Summary
-----------------
Conventional hemodialysis requires transient systemic anticoagulation to prevent blot clotting after contact with the extracorporeal circuit. However, low molecular weight heparin (LMWH) or unfractioned heparin are contra-indicated in dialysis patients at risk for hemorrhagic complications. In this setting, several procedures theoretically allow dialysis without systemic heparinization, but randomized studies to compare them are lacking. The gold standard is the use of iterative rises of the extra corporeal circuit with isotonic saline ( rises ). Two emerging procedures are increasingly used : continuous pre-dilution of the arterial line ( pre-dilution ) and the use of a specific dialysis membrane (NEPHRAL 400 ST) coated with heparin immediately before use ( heparin adsorption ).

Detailed Description
-----------------
Conventional hemodialysis requires transient systemic anticoagulation to prevent blot clotting after contact with the extracorporeal circuit. However, low molecular weight heparin (LMWH) or unfractioned heparin are contra-indicated in dialysis patients at risk for hemorrhagic complications. In this setting, several procedures theoretically allow dialysis without systemic heparinization, but randomized studies to compare them are lacking. The gold standard is the use of iterative rises of the extra corporeal circuit with isotonic saline ( rises ). Two emerging procedures are increasingly used : continuous pre-dilution of the arterial line ( pre-dilution ) and the use of a specific dialysis membrane (NEPHRAL 400 ST) coated with heparin immediately before use ( heparin adsorption ). We propose a monocentric prospective randomized open study to compare  rises ,  pre-dilution  and  heparin adsorption  in chronic hemodialysis patients with contra-indication to the use of LMWH. Main criteria will be extra-corporeal circuit clotting, with dialysis efficiency and tolerance as secondary criteria. Comparison will be made on grounds of  n-of-1  trial, i.e. series of randomized cross-over tests in individuals. We have planned to include 75 patients in this study, with 1050 LMWH-free dialysis sessions. We hope to demonstrate chat by comparison wit rises, pre-dilution and heparin absorption techniques reduce the rate of extra-corporeal circuit by 30 and 50% respectively. We also hope to show that heparin adsorption (i) better preserves membrane integrity throughout the dialysis session, resulting in enhanced dialysis efficiency ; (ii) avoids extra fluid infusion and ultrafiltration, resulting in better dry weigh achievement and better clinical tolerance.

Official Title
-----------------
Chronic Hemodialysis Without Systemic Heparinization : a Randomized Study

Conditions
-----------------
Contra-Indication to the Use of Low Molecular Weight Heparin

Intervention / Treatment
-----------------
* Procedure: Dialysis without systemic heparinization


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Chronic hemodialysis patient Low molecular weight heparin contra indicated for at least 3 consecutive hemodialysis sessions. Exclusion Criteria: Acute renal failure Access flow < 250 ml/mn) Per dialytic Blood transfusion or parenteral nutritional support Systolic BP < 80 mm Hg Hemoglobin > 13 g/dl

Ages Eligible for Study
-----------------
Minimum Age: 18 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Dialysis without systemic heparinization<br>Dialysis without systemic heparinization | Procedure: Dialysis without systemic heparinization<br>* Dialysis without systemic heparinization<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Need for stopping the meeting for coagulation of the circuit of dialysis: -either complete coagulation of the circuit |  | during dialises | 
| or coagulation partial of the circuit (a clot is noted in the lines or the trap with bubbles |  | during dialeses | 
| -or increase in the venous pressure (statement) of the circuit of more than 50 that is to say increase in the venous pressure (statement) of the circuit of more than 50 % beyond its initial value |  | during the dialeses | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Loss of effectiveness of dialysis? dialysance of urea during the meeting (online measurement carried out by the generator of dialysis) |  | during the dialeses | 
| Loss of effectiveness of dialysis overloads hydro-sodic persistent (weight of the patient at the end of the meeting: + 500 grams compared to the basic weight) |  | during the dialeses | 
| Tolerance of the meeting of dialysis clinical side effects (cephalgias, cramps, arterial hypotension |  | during the dialeses | 
| Tolerance of the meeting of dialysis hemorrhagic accidents to at the time the 48 hours following the meeting of dialysis |  | 48 hours following the meeting of dialysis | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Hemodialysis, Heparin, Clotting