Microbubbles may occur in the organs in hemodialysis patients, a case report

[greg10]

Microbubbles may occur in the organs in hemodialysis patients, a case report

Summary:  This case strongly support the MB (micro bubbles) contaminate blood in the tubes of the HD device.  Besides into the lungs, MB pass the lungs, into the arteries, and can be dispersed throughout the body.  These data strongly support that MB cause embolies and organ impairment.  Industry should focus to minimize this side effect of HD.

http://journals.lww.com/asaiojournal/Citation/2011/03000/Asaio_Renal_Abstracts.4.aspx


From the same group:
Microemboli, developed during haemodialysis, pass the lung barrier and may cause ischaemic lesions in organs such as the brain
http://ndt.oxfordjournals.org/content/25/8/2691.abstract

Ulf Forsberg1, Per Jonsson2, Christofer Stegmayr2 and Bernd Stegmayr2
+ Author Affiliations

1Medicin-Geriatriska Kliniken, Skellefteå lasarett, Lasarettsvägen 29, 931 86 Skellefteå Sweden
2Department of Internal Medicine, Division of Nephrology, Norrland University Hospital, Umeå Sweden
Ulf Forsberg; E-mail: ulf.forsberg@gmail.com
Received November 15, 2009.
Revision received February 1, 2010.
Accepted February 12, 2010.
Abstract

Background. Chronic haemodialysis (HD) may relieve some medical problems of terminal uraemia, but the life expectancy of patients is still significantly shortened, and there is a greatly increased morbidity. This includes pulmonary morbidity and chronic central nervous system (CNS) abnormalities. Previous studies have shown that a considerable amount of air microbubbles emanate within the blood lines of the dialysis device and pass the air detector without sounding an alarm. The aim of this study was to investigate whether microemboli can pass to the patient and whether they could be detected in the carotid artery.

Methods. A total of 54 patients on chronic HD (16 with central dialysis catheter) were investigated with an ultrasound detector (Hatteland, Røyken, Norway) for the presence of microemboli at the arteriovenous (AV) fistula/graft and at the common carotid artery before and during HD. Measurements were taken for 2 and 5 min, respectively. Non-parametric paired statistics were used (Wilcoxon).

Results. The median number (range) and mean ± SD of microembolic signals detected at the AV access site before commencing dialysis and during HD were 0 (0–3) and 0.2± 0.5 versus 4 (0–85) and 13.5 ± 20 (P = 0.000); at the carotid artery, 1 (0–14) and 1.7 ± 2.9 versus 2 (0–36) and 3.5 ± 5.8 (P = 0.008).

Conclusions. The infused and returning fluid from HD devices contains air microbubbles that enter the patient without triggering any alarms. These small emboli pass the lung and may cause ischaemic lesions in organs supported by the arterial circuit, such as the brain.

[jbeany]

Huh.  I could have used this when I got witched at for clamping my own line when a tech returning my blood at the end of run was totally ignoring the amount of air going in with it.  "It won't hurt you!"  Uh-huh.  Easy for you to say!

[tyefly]

Micro-bubbles that end up in the blood system should be eliminated to the best that you can.  Quite simply, you cannot get rid of them all.  The drain line is a non issue since that is the waste line, but the saline line is not.

I snap and tap all of my lines together, not separately after letting them "cook" for a while as the small bubbles come together into larger bubbles. Some studies have shown you can get rid of about 70% of the bubbles or more with close attention.  That is 70% less bubbles impacting your lungs causing small micro clots at the level of the lung. I start with the three saline/blood lines closest to the saline bag and then work over to the other end. I don't worry about the yellow line.  I tap the pressure pod which collects air and then I go to the artificial kidney and tap it into the palm of my hand, I don't tap it against an object to avoid any cracks in the material.  I repeat this before I pick my scabs and after I pick my scabs before hitting the stop button on the 23 prime.

The Saline line is another issue.  After I have hooked yellow to yellow, green to green and white to white, I do tap from the bottom to the top of the line all the bubbles I can see. You simply cannot hook up any of these lines and not get some small amount of air in the line, especially with the blood lines. It takes about one minute with the saline line simply leading the bubbles all the way up the line and tapping at the spike to get them all the way out.  I have lost a couple "doses" of my blood by an 11 Alarm when I start my rinse back because of air in the saline line.  Paying close attention at the start of dialysis to the saline line avoids this complication and helps me keep my precious little blood at the highest possible level.

I should note that I don't use the standard disconnect of the arterial blood line for my rinse back, but instead, use the saline line to clean the venous end and then the arterial end.  I place a hemostat below the saline infusion point so that it stops bringing in arterial blood, any small clots in the saline line and any small bubbles goes into the kidney as you start to rinse the venous line and the upper part of the arterial line.  I then stop the rinse back and place the hemostat above the saline infusion port and let gravity clear the lower arterial line.  I then place the hemostat below the saline infusion port and use the machine to clean the rest of the upper arterial line going by the pressure pod, the kidney and the venous line.  I avoid breaking the lines to do the rinse back because that is another point of possible blood contamination.  I can completely clean my lines with them still closed and then once they are clean, I open and disconnect them without any further rinsing once again to avoid possible blood line contamination. 

One of the biggest risks of dialysis is blood borne infections.  In my opinion, this helps reduce that risk significantly. The number of bacteria that reside on the size of a pin head would astound you.  It doesn't take a large contamination to cause an adverse outcome.  I don't believe that is taught as a rinse back method to most folks, but some may remember this as the standard in-center rinse back for a lot of folks.  It may take  more saline to accomplish than the other method, but for my own use, that is not an issue since I don't have fluid restrictions at this time.  As with all issues, it may not apply to your situation so discuss any information placed here with your own medical team first.  In my opinion, it just helps reduce the daily risk of blood borne infections which can be deadly.  Be careful out there folks, it is a daily battle.

This is what Hemodoc wrote in a thread talking about snap and tap...to add to the topic.... 

    Great info  Greg10

[boswife]

Im big on the "cooking" and much snap and tapping..  Another thing that i think 'dan" said was during the 23, pinch the red line for just a second.  It creates a vacume effect and watch those bubbles flow through that blue line.  So tye, do you 'rince back' like suggested?  I just had asked about that on the nxStage site but havent used as yet. 

Nice, well actually yucky,  important info greg10....  Thanks for sharing!