Beginner with OB epidurals

there are 2 main types of catheters, one has a guidewire and is a "stiffer" plastic, one is very pliable. i have been told that the one with the guidewire that is stiffer has a higher incidence of migrating into the sub arachnoid space. if you dont get flow through the tuohy it's kinda hard to say exactly how you wet tapped. i had a similar occurance not long ago, little old lady got a t12 level after the test dose, complained of a h.a. went throught the whole deal where is the cath etc. well we dosed it slowly and it was fine.

good luck,

ps i find that using the portex plastic syringe with water and a continous pressure tech works well for me.

d

I have just completed my first week of a 7 week OB rotation and I finished it off with a "wet tap" instead of an epidural. The patient was a 19 y/o who was 5'5" and 135 pounds. I had no trouble with the placement at L4-5; the catheter threaded great, the 3cc test dose was negative and I had negative aspiration of the catheter while sitting so I taped the catheter in place. BEFORE dosing the catheter, we turned the patient supine and then she started saying her feet were getting numb and her BP dropped and she got "sleepy". Then when I aspirated the catheter I got fluid. We immediately did a blood patch, pulled the catheter and waited 1 1/2 hours before trying again. Although I was "gun shy" about it, I again did the epidural at L3-4 and had no trouble advancing the Touhy and got good LOR, negative aspiration and threaded the catheter easily and instantly got + aspiration in the catheter. It took the MDA another 20 minutes to get a working epidural.

Needless to say I ended the week on a down note and am quite frustrated with the epidural. I know it takes practice and you pretty much have to just do them to learn how. Does anyone have any suggestions on learning how to place an epidural? How did you learn how to do them? My preceptor and MDA both said my technique was very good and they don't know what happened. On a good note, I did sucessfully place 3 others this week (how I don't know). Any advice or personal stories would be great!

Sprout

Sprout, your second catherter may have not been intrathecal. After placing the toughy needle the first time if you bolused the needle (like many including myself do) then that fluid plus the fluid from the first leak would be in the epidural space. The positive aspiration could have been CSF and local anesthetic in the epidural space. A trick is to set the catheter down and see if fluid spontaneously comes from it. This is a gut feeling situation determined by the way the toughy felt going in and the flow of fluid coming out but at times a difference between epidural fluid and intrathecal CSF can be known, a test dose will confirm either.

On another note you are in Birmingham. I did my anesthesia residency there and graduated in 2003 by your username I think I may know you. Send me PM.

hmm... so you had an intra-thecal catheter... no biggie, just wait till the motor blockade resolves then run it as an intra-thecal labor analgesic.... patients LOVE those, so much better than an epidural... Just make sure everybody knows it is intra-thecal so that there are no inadvertent spinal boluses :) .... by the way, doing a prophylactic blood patch is not based on current evidence based medicine....

Where I'm training intrathecal cathetes are a no-no, d/t a high than acceptable level of permanent nerve damage, which I thought was the case nation wide.

I agree with prophylactic blood patches not supported by evidence...but probably a clinical call in this situation, where you have two wet taps in a row.

Interesting case.

I've done a few more than 50 epidurals so far in my training, and I was just saying the other day that statistically im due for a wet tap. Especially now that I'm getting braver and not taking out my stylet until I've reached ligamentum flavum.

.... by the way, doing a prophylactic blood patch is not based on current evidence based medicine....

It was the idea of the MDA that was with us, he's been doing this for MANY years and was adamant we do one.....oh well.

Tomorrow starts another new day in the wonderful world of OB anesthesia......let's hope for better "luck" this week and the next 6 weeks of my rotation! :)

Sprout

Where I'm training intrathecal cathetes are a no-no, d/t a high than acceptable level of permanent nerve damage, which I thought was the case nation wide.

I agree with prophylactic blood patches not supported by evidence...but probably a clinical call in this situation, where you have two wet taps in a row.

Interesting case.

I've done a few more than 50 epidurals so far in my training, and I was just saying the other day that statistically im due for a wet tap. Especially now that I'm getting braver and not taking out my stylet until I've reached ligamentum flavum.

The reports of permanent nerve damage stem from the use of microbore catheters and high concentration lidocaine. Not the catheters or local anesthetic concentrations in use currently.

Mike

Just wanted to add, why change something that is working (I.E. removing the stylet before reaching flavum).

Just my thoughts,

Mike

I'm not questioning the technique of intrathecal catheters or the cause of complications associated with their use, but rather the medicolegal situation one is placed in if he/she chooses to use the anesthesia technique. It was my understanding that the microcatheters were no longer for sale in the USA, due to the incidence of cauda equina syndrome.

Are other practioners using intrathecal catheters in the US? Perhaps we are behind the times.

Regarding the change in technique... I gradually changed my technique because as I gained expereince I was better able to differentiate the ligaments as I passed the needle. Removing the stylet as I reach flavum not only results in a faster epidural (a bonus for laboring women), but I am more confident in the correct placement.

Sprout

Relax. Enjoy this rotation. I went into it dreading OB, because I hated it so much in nursing school. I found that I loved doing OB anesthesia, though, and still do. (OK, well, maybe if our patients could be a little more timely in thier deliveries, but I digress.) I got one wet tap in school, and have had one since I got out of school. They happen. Don't let that rattle you. The truth is that if you haven't had a wet tap, you just haven't been doing epidurals very long.

As to intrathecal catheters, they seem to be coming back into fashion. We have discussed them here where I work. No one wants to put one in intentionally, but if it's there, why not use it? There seems to be some pretty strong evidence that suggests that the presence of the catheter may cause some irritation to the dura, leading to better healing once the catheter is removed, and reducing the need for blood patches.

Anyway, I'm going to an OB anesthesia conference this week in San Francisco. If this is discussed, I'll put more up here later.

Kevin McHugh

Sprout

Relax. Enjoy this rotation. I went into it dreading OB, because I hated it so much in nursing school. I found that I loved doing OB anesthesia, though, and still do. (OK, well, maybe if our patients could be a little more timely in thier deliveries, but I digress.) I got one wet tap in school, and have had one since I got out of school. They happen. Don't let that rattle you. The truth is that if you haven't had a wet tap, you just haven't been doing epidurals very long.

Anyway, I'm going to an OB anesthesia conference this week in San Francisco. If this is discussed, I'll put more up here later.

Kevin McHugh

Thanks for the words of encouragement! Today I made 4 attempts and successfully placed 1 without any help at all.

I just keep on keeping on......

Sprout

like said above.... the catheter issues are old... In fact, microcatheters are BIG in Europe now and are on their way through the FDA process - some of the microcatheters are 32 Gauge!!!! In fact most major OB insitutions (>10,000 deliveries/year) such as Parkland, Brigham & Women's etc routinely place Arrow catheters upon wet-tapping - unless advancing the catheter is painful to the patient (against a nerve).

Prophylactic blood patches have been tried... Does not necessarily decrease the likelihood of a PDPH, and in fact there are reports of the blood entering though the dural hole and causing arachnoiditis so early in the game.... The other issue is that you are now putting the patient into an awkward situation where you are introducing a possibly contaminated blood product in the epidural space/risking a repeat wet-tap in a situation when there is NO clinical indication --- In fact, the reported PDPH rate is lower than previously reported. Most studies show that it is more like 50-60% instead of the 75-80% that we used to think was the common incidence. So in fact, the patient may NOT even develop a PDPH and she has now been exposed to an intervetion she didn't need....