Alteplase for Blood Flow Restoration in Hemodialysis Catheters

Study Overview
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Brief Summary
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We are investigating a new way of administering alteplase to remove clots from hemodialysis catheters. Currently, alteplase is left to dwell inside the catheter between dialysis treatments to dissolve the clot and restore blood flow through the catheter. We have developed a new way to administer alteplase by advancing it to the tip of the catheter at regular 10 minute intervals. We hypothesize that our new push protocol will dissolve clots in hemodialysis catheters better and faster than the current dwell method.

Detailed Description
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Central venous catheters are commonly used for vascular access in the hemodialysis population. A common complication is low / no blood flow through the catheter due to clots. These are serious situations because patients may miss dialysis sessions and suffer significant morbidity. In an attempt to dissolve the clots and restore blood flow, thrombolytics are frequently instilled into the catheters between dialysis sessions . However, we have developed and new push protocol that advances fresh thrombolytic (alteplase) to the tip of the catheter in order to facilitate more effective and faster removal of the clot. We hypothesize that our new push protocol will dissolve clots in hemodialysis catheters better and faster than the current dwell method.

Official Title
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Alteplase for Blood Flow Restoration in Hemodialysis Catheters: A Randomized Prospective Clinical Trial

Conditions
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Thrombosis

Intervention / Treatment
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* Drug: Alteplase push protocol
* Drug: alteplase dwell arm


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adults > 18 yrs old Hemodialysis patients Vascular access with a permanent catheter No prior rt-PA use in the catheter over the previous 21 days One rt-PA instillation per catheter (i.e. we will only document the results of 1 rt-PA instillation per catheter. Numerous rt-PA instillations in the same catheter will NOT be considered new events, and not entered into the study) Exclusion Criteria: Critically ill patients in the ICU setting. Contraindications / cautions with alteplase use including: known hypersensitivity to alteplase or its components (l-arginine, phosphoric acid, polysorbate 80), patients with known conditions associated with bleeding events (e.g.intracranial bleed in last 4 weeks, major hemorrhage in last 4 weeks (Hgb drop of 20 g/L)), recent surgery (<48 hours), recent biopsy (<48 hours), hemostatic defects including severe hepatic disease, or current intracranial / intraspinal neoplasm. Hemodialysis catheter has been in the patient less than 14 days.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

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


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: 1<br>Alteplase used by normal dwell procedure | Drug: alteplase dwell arm<br>* alteplase 2 mg / lumen. Instill and let it dwell for 30 minutes. Assess catheter and allow to dwell for a total of 2 hours if necessary<br>* Other names: rTPA;|
| Experimental: 2<br>Alteplase given by an new push protocol | Drug: Alteplase push protocol<br>* alteplase 2 mg / lumen. Instill and wait 10 minutes, instill 0.3 ml normal saline, wait 10 minutes, instill 0.3 ml of normal saline, wait 10 minutes and aspirate.<br>* Other names: rTPA;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Proportion of patients with pre-thrombolytic blood flows less than 200 ml/min achieving a sustainable post thrombolytic blood flow > or = 300 ml/min. |  | 4 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Highest recorded sustainable blood flow (ml/min) pre- and post- thrombolytic administration. |  | 4 hours | 
| Change in Kt/V from the treatment before thrombolytic administration compared to the treatment after thrombolytic administration. |  | 72 hours | 
| Change in litres processed / time from the treatment before thrombolytic administration compared to the treatment after thrombolytic administration. |  | 72 hours | 
| Serious adverse events including major bleeding within 24 hours of alteplase administration |  | 30 days post-last dose | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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catheter, hemodialysis, dysfunction, thrombolytic, alteplase