My apologies if this is a dumb question, but I've asked around at my children's hospital and haven't found anyone who can answer this. What is the pathophysiology when you're trying to place an IV, no blood return so you're pulling back to try again and you get blood return? (We call this "backing out" of a vein, not sure if everyone calls this the same thing)
Obviously, at some point the vein was nicked or entered, yet there wasn't enough blood return for it to be visible. Almost every time I've seen someone do this (or done it myself), we weren't able to get the IV in. It ends up being blown.
Thanks for your input!
Nov 17, '08
There may be several causes for this phenomena.
1. Since you are in pediatrics the most likely scenario is that you were actually in the vein and without seeing a flashback,you pulled the device back and that is when you got the flashback. Since,you are now entirely out of the vein it is almost impossible to re-enter that vein with that attempt. Sometimes you can anticipate a slow flashback and take some actions and be prepared for it. This can often happen with dehydrated patients,pts with a low BP,pts on inotropes,pts that are very stressed or frightened about the procedure,just to name a few. On some products like the braun intocan or the intima catheter you can remove the flashplug,which will give you a faster flashback. You can also be very aware of where your catheter is during your attempt and if you think you should be in the vein and/or feel the "pop" into the vein....WAIT for that blood return. If no blood always pull back the catheter so very slowly so if you are in the vein you can save it ...sometimes.
2.Sometimes this also occurs when you have nicked the vein at some point but was never fully in it well enough to advance the cannula.
3. The other common reason for this is a through and through puncture. This means you have entered the anterior wall of the vein and also gone through the posterior wall. This can happen when you have entered at a too sharp angle,the pt unexpectedly moves, or you are miscalcualted the size of the vein and have selected a too large cannula. Then when you pull your catheter back...it re-enters the vein on the way back through and you get that flash and then a hematoma.
4. The other thing to consider here is that when you enter the vein you have to go through the muscular layer and that can cause a venous spasm. These can be fairly strong and inhibit blood return. If I have time I like to place a heat pack or heel warmer on my selected site,even if it looks good and increase my odds at success.
There is no specific name for it...some call it blowing the vein....I just say I nicked it or went through it. If you have gone through a vein there is a way to try to get back into it without sticking the patient again. If you have hit a vein and advanced the cannula and pulled back your needle and then when you go to thread it ...it is not advancing and your blood return has stopped......you can often get it back into the vein. Do not recannulate the catheter if you even can most designs no longer allow that)....very slowly pull back your catheter while observing the flashback chamber...when you get a blood return again try sliding it in again....try this about 2-3 times and if you can get back in the vein you probably will not ever,also you do not want to extend any hematoma. PLEASE note: you do not want to perform this technique if you are planning to give any chemotherapy or vesicants,just as an extra safety measure. I always lock the line for 10 or 15 minutes until a good clot can form over the posterior wall of the vein. As you can see.you need to choose this option carefully.
Hope this answers your question Mary
Last edit by iluvivt on Nov 17, '08
Nov 17, '08
Thanks so much for your helpful post! I'm sure you're right, that a lot of times we've nicked the vessel but just don't have enough blood return until we're backing up. Unfortunately, we aren't able to remove the inner component to get a better flash with the catheters we use.
Thanks for sharing your many years of experience and knowledge!!
Nov 18, '08
You are welcome and I did not even go into the difference between a direct and indirect approach. Pediatric starts are such a specialty. I spend many a 10 hour shift starting one pediatric patient after another,until my head was spinning. Many of my co-workers,although they would start babies and children really loathed it. I never did....I could always stay focused and do all the little things that would make me successful. I think at least 40-50% of getting babies and toddlers is to have someone who knows how to hold properly. What may also help you to decrease the chance of nicking veins or pulling catheters out of veins and losing your chance is to approach the vein from the top. This requires that you make your venipuncture at the skin before the vein so it gives you a chance to drop your angle and slide under the skin so you are on top of the vein...(make sure you have made the venipuncture bevel up). Then after you have got to that point and you are right above the vein increase your angle ever so slightly and enter the vein from the top and then drop your angle again and proceed as normal. This technique works very well with small and pediatric veins and also very sclerotic veins. This minimizes greatly you hitting the vein from the side of it and then going through the other side (through and through puncture but from the side to side way. try it it works great and I ahve taught many a nurse this technique. Another tip to remember is that when you get near the outside wall of the vein (tunica adventitia) the patient wil also feel some pain or discomfort. Some nurses get a little uneasy bat this point band pull the catheter back....and I say keep going you are NEAR THE VEIN.
Last edit by iluvivt on Nov 18, '08