It has been suggested that the home healthcare nurses use the 'POP' technique to resolve catheter occlusions in Groshong PICCs (attaching an empty syringe to the catheter, pulling back on the plunger to create negative pressure, then releasing the plunger to send a vibration down the line that may breakdown the blockage after multiple pulls). This is in an effort to promptly resolve catheter occlusions in the home rather than waiting for them to be seen by the vascular access service (Alteplase is not available in the home setting due to lack of drug coverage).
The nurses are questioning whether this is best practice. There are 2 articles supporting this. But is there a concern of weakening the catheter wall with all of this manipulation or embolizing the occluding material.
Would appreciate expert opinion and perhaps Bard's representative comments as well.
Many thanks,
Daphne
I would never, ever, under any circumstances use this technique. When one of those studies was released about this technique, I wrote a long letter explaining the issues with this procedure. It is far too risky to the catheter and patient. I would flatly refuse to do it unless the individual catheter manufacturers supply a statement supporting that their catheter can tolerate this procedure. I seriously doubt that any of them will provide such information, but if they do, I might reconsider. It is not included as safe method for catheter clearance in the INS standards. So I will not do it. Lynn
Lynn Hadaway, M.Ed., RN, NPD-BC, CRNI
Lynn Hadaway Associates, Inc.
PO Box 10
Milner, GA 30257
Website http://www.hadawayassociates.com
Office Phone 770-358-7861
My vote is with Lynn on this one. Yes they restored patency in the summary below but where'd the clot go? Was the catheter damaged in some way or weakened? The questions are endless. Genentech must have loved that one.
Peripheral-inserted central catheters (PICCs) offer a successful alternative to peripheral venipuncture for long term medication therapy. When catheters become occluded, the nurse must intervene to avoid delayed or missed treatments. Pharmacological interventions are costly and not without risks. The purpose of this exploratory study was to test a mechanical percussive POP technique to restore patency. Thirty PICC catheters were clotted with human blood and incubated for 8 hours in a 35° saline bath. Using the percussive POP technique, a 10-mL syringe with 1 mL of saline restored patency in 86% of the occluded catheters. The safety and effectiveness of the POP technique in vitro was established.
Rich Lewis, RN
Below is from the Groshong NXT IFU. Silicone catheters typically have a low PSI tolerance with ratings between 30-40PSI. This "POP" technique will increase intraluminary pressure dramatically potentially causing catheter damage anywhere along the catheter length. Any irritant or vesicant nature infusate could cause injury on subsequent infusions. I strongly DO NOT support this technique at all, would not perform on any power injectable PICC including the Power Groshong.
• Occluded or Partially Occluded Catheter
Catheters that present resistance to flushing and aspiration may bepartially or completely occluded. Do not flush against resistance. If
the lumen will neither flush nor aspirate and it has been determined that the catheter is occluded with blood, a declotting procedure per
institution protocol may be appropriate.
Timothy L. Creamer RN, CRNI
Clinical Specialist, Bard Access Systems
Florida Division
that strongly support NOT doing this. It's a recipe for success only in giving the patient a thromboembolus and/or catheter embolus.
Mari Cordes, BS RNIII VA-BC
Vascular Access Department
University of Vermont Medical Center
Dear listers,
Fetzer and Manning in 2004 tried the POP technique (10 ml luer lock syringe with 1 ml saline, pull back fully and release up to 30 times) in an in vitro setting. They used blood to clot up 13 3 Fr and 17 4 Fr single lumen groshong piccs. Patency was restored in all 4 Fr catheters and in 11/13 3 Fr catheters. There was no damage to the catheters and no clot material released into the saline bath that the catheters were put in. They refer also to an article by Stewart from 2001. He had used the technique for 4 years in over 50 CVCs, of which 3 failed. They saw no adverse effects, including no catheter damage in the first ten, which they inspected. I took a 4 Fr single lumen gorshong picc and used a 20 ml syringe and "pop"ed it 200 times in under 3 minutes (greater aspiration force in larger syringe) without damage to the catheter. I know, small study, but still.
Is this really so risky? Could it not in fact be added to the arsenal of methods for restoring patency in occluded catheters? Having to pull and insert a new line is not without risk, that we know. I can send the refs to any who wants them.
Mats in Stockholm
Refs:
Fetzer SJ and Manning GPD 2004, Safety and efficacy of the POP technique for restoring patency to occluded PIC catheters, Appl Nurs Res 17(4)297-300
Stewart D 2001, The percussion technique for restoring patency to central venous catheters, Care of the Critically Ill 17(3) 106-7
I read the 2004 article, found numerous problems with it and wrote a letter to the editor at that time. I don't think they ever published it, but this is not the safe technique those authors made it sound like it was. It has been a long time, so don't remember the points I made in my letter. But I definitely would not regard this study as establishing that this is a safe procedure. Also, there are no catheter manufacturers, to my knowledge, that include this technique in their instructions for managing catheter clearance. That means that this practice is not supported or endorsed by the catheter manufacturer. If you did this technique and cause a serious negative outcome for your patient and there was a lawsuit, the catheter manufacturer would be removed from the lawsuit because the nurse performed this procedure that was not recommended by the manufacturer. This means that the nurse and the employer would bare the entire legal burden for the patient injury. This is a critical element in the US.
Occluded catheters do not always mean catheter removal and reinsertion. There are many techniques for restoring patency other than this pop method. These methods require a thorough assessment of what lead up to the occlusion problem so that the appropriate solution for instilling into the lumen can be chosen. The Catheter Clearance Standard from the Infusion Nursing Standards of Practice does not include this as a safe alternative. Occlusion is frequently in the vein around the catheter, not inside the catheter lumen itself. This technique would not address this problem and could be dangerous. So in my opinion there are many reasons to reject this practice. Lynn
Lynn Hadaway, M.Ed., RN, NPD-BC, CRNI
Lynn Hadaway Associates, Inc.
PO Box 10
Milner, GA 30257
Website http://www.hadawayassociates.com
Office Phone 770-358-7861
Thanks Lynn,
I agree that manufacturers not endorsing it is of course an important issue, but have any manufacturer specifically said that it is unsafe?
I agree that assessment of what could have lead up to a problem always must be done prior to any intervention. But that is a universal fact and not specific for the pop technique or any other practice. Also, I think, the established method of tPA instillation should be tried first if an intraluminal clot is thought to be the most likely cause of dysfunction. But my experience is that if you have a long intraluminal blood clot, chances are that tPA instillation will not be able to restore patency. Could this not be something to try if nothing works and the only other choice would be pulling the line?
Lynn, please let me know what you see as the dangers with the pop technique, what the possible serious negative patient outcomes might be.
How could we prove if the technique is safe or unsafe without having to wait for the manufacturers to take the initiative?
Anyone else with thoughts on this?
Mats
I had to do some digging to find my original letter to the editor of Applied Nursing Research about this study. Here are the highlights of what I wrote.
1. The study was done with Groshong, therefore the presence of the valve prevents the generalization of this technique to all catheters without internal valves.
2. The researchers made no attempt to measure the pressure generated by this technique, so there is no way to determine if this was or was not within the max limits recommended by the manufacturer.
3. In vitro conditions can not duplicate in vivo conditions. After days, weeks, months of use, there could easily be weakened areas in any catheter and these areas could rupture with this technique.
4. The researchers neglected the whole issue of breaking biofilm, present in all in vivo catheters but not in the in vitro study. Biofilm breakage is thought to be the primary cause of attached biofilm moving into the bloodstream and causing a BSI. Thrombus and biofilm are well documented to be intermingled within the catheter lumen. This is the primary reason that Genentech's instructions for Cathflo state to aspirate the catheter before flushing when the declotting procedure is used.
5. Their published study did not address the other causes of lumen occlusion and led one to think that intraluminal blood clot was the only cause - not true. What does this technique do to the other mechanical and drug precipatate causes? For instance, this POP technique performed against a catheter closed with pinch off syndrome could easily result in catheter damage.
6. In the absence of proven safety with this technique, one can only apply our current knowledge which leads me to think that BSI, emboli, and catheter damage are all strong possibilities with this technique.
I did receive a letter from the editors stating they would send my letter to the study authors, but I never received any further information from the authors about my concerns.
I would never expect any of the catheter manufacturers to investigate this technique sufficiently to allow them to add this to their instructions for use. This would need to be cleared by the FDA and I doubt seriously if any manufacturer would undertake this. So even if you did do a study and found there were no negative clinical outcomes with it, you still would not have a catheter manufacturer including it in their instructions. I don't even know how you would conduct such as study. The liability would be so great that I don't think you could get an Investigational Review Board to approved such an in vivo study. Therefore I would stick with the chemical treatments for opening occluded lines. Thanks, Lynn
Lynn Hadaway, M.Ed., RN, NPD-BC, CRNI
Lynn Hadaway Associates, Inc.
PO Box 10
Milner, GA 30257
Website http://www.hadawayassociates.com
Office Phone 770-358-7861
As so many times, lots of knowledge and lots of food for thought.
Mats
Personally I would like to see what the popping technique does to various catheters with a micro manometer attached. I do not understand how pulling a vacumme (negative pressure , psi) on a static clotted line (zero psi) with a saline filled syringe and releasing the plunger, reintroducing the negative psi back to the original static clotted line (zero psi) would create any positive pressure? The notion is that some how we are creating a positive pressure (in a closed system) by pulling and releasing a vacumme? Unless there is some fluid dynamics principle that applies? Do we have any fluid dynamics experts out there?
Peter Marino R.N. BSN CRNI VA-BC Hospital based staff R.N. with no affiliation to any product or health care company.
What are the theoretical basis for this technique to work or not?
Is it possible to say what kind of pressure, how high PSI, it theoretically could generate?
Mats
Mats, try asking over here http://www.forumjar.com/forums/Fluid_mechanics and post the response back here. If I were a betting man, I would be willing to bet there is very little (more like zero) psi generated by pulling and releasing a vacumme in a clotted catheter. Although the rush of fluid MAY create a "shock wave" but again, I don't think the catheter is sustaing any increase in psi.
Peter Marino R.N. BSN CRNI VA-BC Hospital based staff R.N. with no affiliation to any product or health care company.
.
that is not very useful clinically. Popping technique won't get rid of fibrin tails, extraluminal thrombus. Popping might temporarily remove a a small amount of occlusive material, but not a fibrin tail or extraluminal thrombus that would continue to cause problems.
It may be interesting to figure out the fluid dynamics in this situation with different catheters, but if we already have a safe, well-tested and proven technique to clear catheters (cathflo), and we could very well be causing sessile biofilm to become planktonic with popping method, and we don't know for sure if we'd be weakening silastic material over time - why do it?
In addition, withdrawal occlusion and total occlusion are symptoms of catheter malposition - into IJ, azygous, or other smaller vessels. Another reason that we should choose a safe and well tested method to clear catheters.
Mari Cordes, BS RNIII VA-BC
Vascular Access Department
University of Vermont Medical Center
Any time I can discover more information about the dynamics of a catheter, it is useful. Although it may not appear to be useful information in a given circumstance. The information may be useful in the future and possibly applicable to other situations. So I never throw out or disregard data ;~)
Seems to me that the main areas of concern center on the assumption that this pop technique produces a positive pressure in the catheter. If creating and releasing a vacuum with a fluid syringe doesn’t produce pressure. Then the ejection of catheter contents catheter fatigue, rupture or damage from the pop technique is questionable. Wouldn’t the content be aspirated out of the catheter if there is no force applied to the syringe plunger?
Granted that this pop technique will not fix P.W.O. (persistent withdrawal occlusion) caused by fibrin build up, mural thrombus or malposition. The “safety” of cathflo, is dependent on the clinician’s proper use of the product. It is already evidenced based that improper use of cathflo may result in the release of microorganisms into bloodstream (CRBSI). It is the clinician’s technique that makes it safe. This can be said about many things.
Is the pop technique dangerous, is it safe, is it useful or cost saving? The jury is still out for me.
Peter Marino R.N. BSN CRNI VA-BC Hospital based staff R.N. with no affiliation to any product or health care company.
Catheters are plastic tubes. Some have external portions and some do not. Manufactures of catheters do not recommend pushing upon resistance which would the POP method describes. In a port should you push against pressure the weakest link to the port is at the stem where the port attaches to the catheter. Pushing against pressure could cause a hole (it does happen) or a tear or a separation. At this point the infusate may not go into the vascuar system. Any damage to a port is not visualiized. For a catheter with external hubs and tubing what is seen with a forceful push is balloning of the tubing, pinholes in the catheter, break at the bifurcation of the catheter. The result can be an embolized catheter. Not to mention leaking drug, increased risk of infection, line replaceent etc. To use the "POP" method may lead one to patient injury. Mufactures of catheters do not suggest pushing against resistance. For lines totally blocked an infusion of Cathflo may be necessary to open the line versus the POP method.
For patients with a suspected contraindicatoin to CathFlo I sugget a consultative call to the MD to determine the best approach for the patient. As far as septic showers I suggest reading the COOL 1 and Cool 2 trials as the occurence of sepsis in over 1,000 patients was less than 1% of all the declots done in this study.
Kathy Kokotis
Bard Access Systems
I can not find a reference where applying pressure on the syringe plunger is part of the "pop technique". Nor do I see it being suggested for any other type of venous access device other than a PICC. The COOL studies are a moote point as I have already said that CRBSI is an issue if cathflo is NOT used properly. But again, I do question this "shock wave" explanation.
researcharchive.vuw.ac.nz/bitstream/handle/10063/659/thesis.pdf?
Fetzer, S. J., & Manning, G. P. (2004). Safety and efficacy of the POP technique for restoring patency to occluded PIC catheters. Applied Nursing Research, ...
Pg 201
1 Explanation given to patient
2 Hand wash. Don non-sterile gloves
3 Fill 10ml Luer Lock syringe with 1-2mls of Normal saline
4 Ensure extension set is clamped
% chlorhexidine/alcohol swab (Briemarpak) to hold end of extension5 Open out 1
8 Unclamp extension set
9 With syringe tip facing downwards, pull plunger fully back and then release.
Release of the plunger may cause a "Pop" sound, sending a shock wave down the
plunger
10 Keeping tip of syringe facing downwards, repeat this "pull back and release
plunger", at 2 second intervals, up to a maximum of 30 attempts
11 At some stage, you should notice a free flow back of blood through the syringe
due to it being unlocked with this "Pop" technique.
Peter Marino R.N. BSN CRNI VA-BC Hospital based staff R.N. with no affiliation to any product or health care company.