INS Standard 32.II.B states that midlines are not appropriate for infusates with an osmolality above 600. Below are some common contrast agents and roughly half have an osmo above 600, four more are right on the border. My question is how are clinicians adopting new power midlines into their facilities so as to not violate standards of practice? Are you getting buy in from the radiology departments to switch to low osmo agents? If a patient is injected early on in the stay with a high contrast agent are we setting the midline up for a thrombosis? (Resulting PE's do kill some people right?) Just wondering how others are doing this as we contemplate obtaining these products.
Agent Osmolality
Isovue®-200 (Bracco) Iopamidol Nonionic Low...413
Isovue®-250 (Bracco) Iopamidol Nonionic Low...524
Isovue®-300 (Bracco) Iopamidol Nonionic Low...616
Isovue®-370 (Bracco) Iopamidol Nonionic Low...796
Omnipaque™ 140 Iohexol Nonionic Low.............322
Omnipaque® 180 Iohexol Nonionic Low.............408
Omnipaque™ 240 Iohexol Nonionic Low.............520
Omnipaque™ 300 Iohexol Nonionic Low.............672
Omnipaque™ 350 Iohexol Nonionic Low.............844
Optiray® 160 Ioversol Nonionic Low..................355
Optiray®240 Ioversol Nonionic Low...................502
Optiray® 300 Ioversol Nonionic Low..................651
Optiray® 320 Ioversol Nonionic Low..................702
Optiray® 350 Ioversol Nonionic Low..................792
Oxilan® 300 (Guerbet) Ioxilan Nonionic Low......585
Oxilan® 350 (Guerbet) Ioxilan Nonionic Low......695
Ultravist® 150 Iopromide Nonionic Low.............328
Ultravist® 240 Iopromide Nonionic Low.............483
Ultravist® 300 Iopromide Nonionic Low............ 607
Ultravist® 370 Iopromide Nonionic Low............ 774
Visipaque-320™ Iodixanol Nonionic Low............290
I would think the issue is more about the ability to detect infiltration with an upper arm placement. The rediology departments I have seen do not make any accomodation regarding osmolality when using an antecubital 20 ga PIV. The fluid dyamics would be even more unfavorable with that catheter and the affected vein area would be nearly the same as a 3inch midline in the upper arm basilic. The only thing I can identify that would be different would be the increased difficulty of spotting extravasation in the deeper vein. I think that until radiology departments are on-board with following the standard in using PIVs, there could still be a 'lesser of two evils" advantage to the midline. I would be interested in networking with someone who has gotten buy-in from a radiology department in following the INS Standard.
Daniel Juckette RN, CCRN, VA-BC
If there is an infilitration (or extravasation with some contrast agents)in the axillia it would be harder to detect and possibly a much more serious injury. My concern is now the injured pt.'s legal counsel asks "why did you violate INS standards?"
Also the PIV is a 2-3 day access and the Midline is a 3-4 week access. Injuring the intima without infiltrating with the power injection will cause the PIV to be changed, if not immediately then soon afterward. But the same intimal injury with a midline could brew undetected till there is some major thrombosis.....I think the PIV is the lesser of two evils. It seems to me that people are jumping on the power midline wagon thinking it will make clinicians lives easier. I had a wise old nursing professor who said to me if we put the patients safety first in all our actions, we will have a long and enjoyable career.
Stephen Harris RN, CRNI, VA-BC
Chief Clinical Officer
Carolina Vascular Wellness
The fact remains that these contrast agents, which are considered to be medications, are being given through peripheral veins now. In fact, I would argue that the need for a high flow rate for a CT scan is not sufficient reason to insert any type of CVAD, although a PICC is the most common choice in that situation. It is a matter of risk vs benefit assessment. I think the risk associated with a CVAD insertion only for a CT scan with contrast and there are no other indications for a CVAD is far greater than a catheter in a peripheral vein that is inserted into a vein that has not been punctured recently, that is less than 24 hours old, that is a large vein in the forearm and not in an area of joint flexion, and that is adequately secured. I am very familiar with the INS SOP. But you must also remember that those statements are practice criteria statements using the word "should". They are not standard statements using the word "shall". Also, this is intended to address continuous or repeated infusion and not 1 time injections or infusions. We do not know where the clinical evidence with take us yet for any of the new catheters with a labeled indication for power injection. I do know that the FDA requires a higher level of evidence be presented to them in order to get clearance to market these new catheters and this did include some clinical work. As with most devices, the clinical outcomes are not known when the device is introduced to the market. And clinical outcomes is what we need. If no one "takes a chance" to use new devices, we would never get the needed evidence to know what those outcomes will be. I was in this same situation when the entire concept of midline catheters was first introduced to the market in 1989. A few nurses in home care saw the potential benefit and begain using them and then published their work. The same needs to happen with any new device. Also, on most adults, do you think that a 3 inch catheter inserted in the mid-bicep area would have the tip reach the axilla? I do not think this would occur on most adults, although we do not live in a one-size-fits-all world. 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
Bard was at INS showing posters of the their new CT power midlines - however, in small print they say "not approved in the US".
Interesting marketing...
Yes, there is one already on the market - PowerWand from Access Scientific is a midline catheter with FDA cleared labeled indication for power injection of contrast. 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
I think we will have to agree to disagree on this one. My experience as a Radiology nurse has taught me a few things about power injection. 1. CT machines often have pressure settings in the 300-325psi range. 2. Many times brand new PIV's that have excellent blood return still end up blowing the vein with injection. 3. We know that literally millions of injections have been performed safely in the central circulation. I think there are two things that are working in favor of central injection over midline position. (and most midlines we insert are 6-7 inches long rather than 3inches. 3inches is about 7 cm and most midlines start at 20cm in the kit!). The first thing is all that pressure is being dumped in a 20 mm vessel. Flow dynamics tells us that the pressure gradient will be dispersed more quickly in a larger vessel, and secondly not only is the vessel larger but there is much more flow to "absorb" the high fluid pressure. By the laws of physics an equal pressure injected into a smaller vein with a lower flow will be "harder" on the vessel wall. That is why so many veins blow on the CT table. When we combine this info with nurses frequently using midlines incorrectly on the floor(Vanco, Acyclovir, Gancyclovir, TPN!) I really think a PICC is much less risky. For equal dwell times the infection rates are comparable. I just spoke at INS about all the preventable deaths and injuries that occur in hospitals each year, I think this group of devices might contribute to the injury part.
As far as liability no matter what INS intent any malpractice attorney with a modicum of intelligence will use that 600 osmo cutoff very effectively if a lawsuit should occur.
Stephen Harris RN, CRNI, VA-BC
Chief Clinical Officer
Carolina Vascular Wellness
Have you seen the study that Dr. Gregory Schears did on power injection through PICC lines? It is called The Perils of Power Injection? I would be curious as to what your thoughts were after you watched.
Teresa Kamps, RN, CRNI, VA-BC
Clinical Operations Manager
Access Scientific Inc.
12526 High Bluff Drive, Suite 360
San Diego, CA 92130
I would like to add a few more thoughts to your message based on my experience. While I do not have the comparable experience in Radiology that you do, I have been the expert on at least 9 legal cases involving extravasation of contrast. My understanding is that all power injectors are set to either 300 or 325 as the maximum pressure however reaching this level requires some type of resistance along the fluid flow pathway. Examples would include a kinked IV set or catheter or a positional catheter. If there is no resistance, there is no increase in intraluminal pressure. This is a fact of the physics of fluid flow. So there will always be a rapid flow rate creating a jet effect from the catheter tip, but the high psi levels set by the machine are rarely reached. I would disagree that there are no complications with CVADs and power injection. In an animal lab, I have watched power injections through PICCs whip and flip so badly that they create lacerations of all sizes in the SVC. This adds to the problem of catheter thrombosis, but I would agree that we have no clinical reports of this probably because no one is looking! At a minimum, the tip migrates to a different suboptimal vein. In 9 legal cases, the osmolarity of the contrast agent is put forward as a factor but it is never the primary factor that makes or breaks the case. There are always numerous other factors such as site selection in the wrist or hand, lack of catheter stabilization, no site assessment by manual flush and aspiration for blood return prior to connecting the power injector. I have never had a lawyer argue that the osmolarity was so great that it required a CVAD and a PIV should never have been chosen. The problem with the osmolarity comes after the extravasation when heat is applied, which compounds the osmotic fluid shift and spreads the contrast in the tissue into contact with larger areas. The ACR Manual on Contrast states heat or cold is a controversial issue, however I have found numeorus studies of contrast extravasation reporting success with cold, therefore it is not a controversial issue in my professional opinion. Also, my comments here are based on a presentation I just gave at INS where I looked at the deviations from the standard of care in all of these cases. So yes these agents are usually hyper-osmolar, but giving them through a PIV has never been an issue in any of my legal cases. Giving them through a non-functioning PIV or one that is in a poor location is the most frequent issues. 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
I have a question for the legal team here. How many cases have been defended or prosecuted for CT contrast infiltrations, through a Midline catheter?....I can see the mechanism behing a peripheral IV accidently dislodging, espectially in the wake of a pressured injection. What I'm have difficulty with is how that can happen with a power injectable Midline extending 15-20 cm into the upper arm?
Now, I'm not talking about continued infusion of infusate with osmolarity above 600, I'm talking about a one time CT with a 30 second injection. I'm very interested in how many cases there were?
Jack Diemer
There is really no way to get an answer to this question. You might be able to do a search of some of the legal databases but I don't have access to them. All of my cases have been through short peripheral catheters with very bad choices for site selection such as the volar wrist. Until now, there have been no midline catheters with a labeled indication for power injection. So I hope there have been no midlines used for this purpose and thus no lawsuits. Now we have the PowerWand, a 3.1 inch midline catheter and a midline from Bard pending FDA clearance. We will not see any cases associated with these devices until there is more widespread use of them. Hopefully these devices, along with the BD Nexiva Diffusics catheters will greatly reduce contrast extravasations. Time and clinical outcomes are needed. 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
The upper limits are rarely reached, actually if they are most power injectors are programmed to shut down automatically. However, pressures just under the maximum allowable are very commonly reached. Pressures of 250-290psi are seen everyday with any CT suite.
Porcine animal studies can be very valuable, but logically I think they are misleading in relation to catheter movement in humans. Pigs have such short legs and the resulting distance from insertion to SVC is a completely different ratio. Also pigs are four legged which completely changes the anatomical relationship of heart to SVC for bi-pedal comparison. I think if there was SVC laceration in humans we would have all heard about this loud and clear. In my mind the evidence of millions of CT injections in humans, and the safe continued use of the PICCs after power injection, is much stronger evidence than a medical device company sponsored pig study which showed "whipping". Again where are the reports of human injury?
Osmolarity and it's effect on human tissue is not completly understood but we know that there is a direct relationship between the pH and osmolarity of an infusate and phlebitis. Phlebitis increases as pH and osmolarity increase. My concern with these devices is not the single power injection(although a contrast extravasation is easier to manage in the arm than the axilla) but the fact that floor nurses and doctors will be comfortable using an extended dwell device for inappropriate infusions which will damage the vein and then we power inject, or we power inject and damage the vein and then use the device for inappropriate infusions. Either way is a bad outcome. In my experience very few vascular access teams have the staffing to go back and check if the infusates that are being used are device appropriate. We even have another thread on this site where the hospital is eliminating INS SOP language to stop those pesky nurses from bugging them about the Vanco/Midline dilemma...outrageous! I have no financial relationship with any PICC or midline company. These devices are probably appropriate in some facilities, but it seems clear to me they also create a large potential for patient injury.
Stephen Harris RN, CRNI, VA-BC
Chief Clinical Officer
Carolina Vascular Wellness
Currently, contrast with all of the above osmoality and pH (which you did not mention, many are above 9) are routinely injected through peripheral IVs now. The radiology nurses and technologists that perform these injections are not aware of the INS guidelnes for peripheral IV catheters. I have in past years presented this information at the annual conferences of ARIN, much to the surprise of the audience. They now realize why extravazation is so common. It is up to the vascular access experts to educate the radiology department about the risks of contrast injection, not just with Midlines but also with PIVs and central cathters and make sure they understand what best practices are and how to minimize the risk to the patient and to their licenses.
I would encourage you all to speak at the ARIN conferences, the AVIR conferences and publish in the ARIN and AVIR newsletters and journals about our knowledge in the shared specialty of vascular access.
Chris Cavanaugh, RN, BSN, CRNI, VA-BC