Case Report: IV access in a dialysis patient: An Evidence free zone!

So the below is only my opinion! We are definitely in an evidence free zone and this is not meant to guide management! However this is my nightmare. 

A 53 yo ESRD is BIB EMS to a small community hospital. Her chief complaint: missed dialysis. She reports staying at her NH and not having been picked up for dialysis for the past week. She is on HD, Tues, thurs, and Saturday. Her last IHD was a week ago and her most recent one was unable to be continued because her graft had clotted off. She does not feel short of breath but does note her body is more swollen. SHe has no other symptoms. Past medical history includes (but not limited to): DM, HTN, ESRD on HD, and a right sided CVA with deficit on the right side. On exam her BP is 224/112, HR is 78, RR 20 (as usual), and afebrile. On exam she is in no acute distress and non-toxic appearing, she is morbidly obese, she speaks in full sentences, she has keloid formation on both sides of her neck and anterior chest wall. She has a moderate contracture on the right arm from her prior CVA, she has a Arteriorvenous graft (AVG) on the left arm with no palpable thrill or bruit. She further has bilateral above the knee amputations. Bilateral radial vessels are palpable no other findings. The nurses are unable to find a vein on the arm with the CVA and tell you they cannot do an IV on her arm with the graft. The lab tech is unable to obtain a blood draw given her skin changes and lack of venous access.  You are asked to obtain blood and you do so by radial arterial draw. Her ECG shows no peaked T waves and her Potassium (K) is 6.8.

So, to sum up this is a 53 yo female on dialysis with a clotted graft, no accessible veins peripherally by 2 different nursing attempts and the charge RN, no accessible EJ on the neck (visually or by US) due to keloid, no accessible mammary veins on the chest due to b/l keloid, no legs, an AV graft on the left arm and the right arm is fixed ADducted and held in flexion and cannot be straightened due to the stroke.

What do you do? Where and How do you get IV access? Do you put in a central line? If so where?

WELCOME TO MY NIGHTMARE AND A COMPLETELY EVIDENCE FREE ZONE!!!!

Where do we start?

As far as IV access goes, we are all aware that we “shouldn’t” use the arm with the AV graft (AVG) or fistula (AVF). But when we NEED blood and IV access as in the above case where do we start? Let’s look at this.

There are slim to none guidelines in this area. The only semblance of guidelines is from the 2006 KDOQI (Kidney Disease Outcomes Quality Initiative, http://www.KDOQI.org). In the section on “Clinical Practice Guidelines for vascular access”, pg 340 states “1.1 The veins of the dorsum of the hand should be the preferred site for IV cannulation.” And  under patient preparation for permanent access states “ In patients with CKD stage 4 or 5 forearm and upper-arm veins suitable for placement of vascular access should not be used for venipuncture or placement of IV catheters, subclavian catheters, or PICCs)

Does this mean both hands? Does this mean after or before placement of the AV access. No one will ever know…

The rationale for these recommendations are for PRESERVATION of the veins to create an AV fistula or graft, and maximize chances or successful fistula placement and maturation. Furthermore it is for prevention of thrombosis. These are the reasons for the PIV cautions. They report the incidence of central vein stenosis and occlusion after upper extremity placement of PICC and venous ports is 7% in 1 retrospective series of patients. PICCs are also associated with an incidence of upper extremity  varies between 11% and 85%. Thus PICCs should not be used in CKD.

And that sums up all the recommendations!

At kidney.org, the housing site for the KDOQI guidelines, there is a post that states:

“Post date: February 10, 2014

I have permitted peripheral IV access in the back of the hand on the same side as the AV fistula. I do not permit IV access above the wrist on the same side as the fistula. I do not permit Peripherally Inserted Central venous Catheters (PICC) access to be placed in any dialysis patient with a fistula. I only permit centrally lines in the Right Internal Jugular position. The KDOQI guidelines recommend right sided central venous catheters, avoiding subclavian catheters and avoiding peripheral IV access in any dialysis patient or pre-dialysis patient. They also mention using the back of the hand veins for peripheral access but avoiding the arm veins for peripheral IV access.”

Obviously not high quality data…

The nurses were unable to obtain IV access or blood from either hand or veins on the chest wall.

Next step for me was to look for an EJ… sadly, no luck too much keloid formation over both sides of the neck nor could I find distended EJ’s visually  or by ultrasound.  Because of the left arm contracture and her soft tissue edema I had a very difficult time finding a deep brachial vein. In my own personal experience I feel the basilic vein is more likely to infiltrate whether you happen to “back wall” the vessel or not. However, after getting more help positioning the patient and have a few people hold her I was able to get a peripherally inserted 20 ga 1.88” (48mm) Angio catheter in the most anterior deep brachial at the level of the mid bicep. Now to find a new pair of underwear!

If that failed, I guess I would have done a right IJ since her graft is on her left arm and guidelines say to avoid Subclavian vessels. Also theoretically, an IO of the right humerus could be done emergently but being a renal patient I’m sure her bone strength is minimal.

So in summary, obtaining IV access in an HD patient would be in the following order:

  1. Dorsal veins in the hand
  2. Peripheral on the contralateral AVF/AVG side
  3. External Jugular (either
  4. IJ contralateral to the AVF/AVG; if CKD 3-5 then Right IJ preferred but either is Ok
  5. If PICC is needed substitute in a tunneled EJ/IJ catheter by IR

Avoid

  1. Above the wrist on the AVF/AVG side
  2. Subclavian central line
  3. PICC

In case you were wondering what the steps are for accessing a fistula I found this wonderful article, by Manning, on how to do that:

Any gauge and type of needle may be used, although a large-bore (14, 16, or 18 gauge) needle is recommended in emergency circumstances. A needle is preferable to an angiocatheter because it is easier to secure with tape under the high pressure of the fistula. A tourniquet should be used when cannulating an AV fistula and removed immediately after cannulation. The tourniquet should be placed in the axilla area and applied lightly. These precautions will help prevent thrombosis, the most common cause of AV fistula and AV graft failure. One should scrub the skin at the puncture site with povidone-iodine, allow the skin to dry, and follow with a scrub using isopropyl alcohol.  The needle should be inserted into the AV fistula at an angle of 20 to 35 degrees until a flashback of blood is noted (The angle should be increased to 45 degrees if the nurse is cannulating an AV graft.) After the flashback, insert the needle up to 0.32 cm (1/8 inch) further and decrease the angle until the needle is flat with the skin. The needle or catheter should be advanced to the hub to prevent bleeding around the insertion site. If using an intravenous catheter, one should be prepared to attach intravenous or saline lock tubing quickly to avoid unnecessary blood loss. Blood flowing through the AV fistula travels at a high velocity, so fluids need to be infused under pressure. One must take care to tape the needle or catheter to the skin securely in a chevron fashion to prevent dislodging.

If the fistula has been accessed in the previous 24 hours and the needle puncture sites are visible, the nurse should take care to access the fistula at least 2.5 cm (1 inch), either proximal or distal, from the previous site to allow healing time and to avoid the formation of an aneurysm. Prior to and after cannulation, the emergency nurse should assess the AV fistula for a thrill and document its presence. The AV fistula can be de-accessed in the same manner as a peripheral intravenous line, with pressure applied after the needle or catheter has been removed. The nurse should take care to hold gentle, nonocclusive pressure for a full 10 minutes at the insertion site.

References:

  1. Manning, M. Use of dialysis access in emergent situations.J Emerg Nurs 2008;34:37-40. Available online 18 October 2007. doi: 10.1016/j.jen.2007.03.018. PMID: 18237665
  2. https://www.kidney.org/blog/ask-doctor/what-recommendation-peripheral-iv-placement-dialysis-patients-avf-and-avg-i-am
  3. February 2012 ASN kidney news. The PICC conundrum: Vein preservation and Venous Access. https://www.kidneynews.org/kidney-news/special-sections/interventional-nephrology/the-picc-conundrum-vein-preservation-and-venous-access

JULY ECG: A BLOCK PARTY

IMG_1377CASE: A 70 yo male presents to the ED with dizziness. He has normal vital signs and his ECG appears as below:

AVD original

ANSWER:

AV Dissociation without complete heart block

DISCUSSION ON COMPLETE AND INCOMPLETE HEART BLOCK

Remember that AV dissociation can occur WITHOUT complete heart block. Let’s discuss blocks. The definition is the every QRS is related to a P and every P is related to a QRS. What we are talking about here is does every P wave produce a QRS complex on the ECG. Now remember even though we are speaking mostly about a test (the ECG) we have to remember that the test does not live in isolation of the physical exam. It’s like looking at an abg where the pH is 7.0 and not asking what the clinical situation is. If its DKA that’s bad, if it’s a seizure, well, that abg will get better on its own.

I think the biggest problem in understanding ECG’s is the terminology. So that will be a big part of this discussion. So just to point out how confusing the terminology is we won’t be discussing bundle branch block. So really when we refer to “heart block” what we are really speaking about is a delay or obstruction in conduction either at the AV node (nodal) or just below the AV node (infranodal) in the bundle of his. AV blocks are usually thought of in “degree’s” of block from first to second. It is a sort of continuum from first degree AV block which is essentially forgettable to complete heart block which can be lethal.  But here again the terminology is confusing. First degree heart block isn’t really block. It’s just conduction at the AV node that is slowed. So, a p wave always produces a QRS but it just might take longer than normal (>200 ms). Also, it essentially has no clinical context and so we won’t give it another thought.

TERMINOLOGY

A note on terminology. When we say conduction in the context of conduction ratios in AVBs, we are refering to the ratio of P waves that conduct to the ventricles. Thus, a 3:2 conduction means that, there are 3 P waves, 2 of them conduct normally to create QRS complexes. This is different than block when we are comparing the number of P present to the number of P waves that have been blocked. For example, a 3:2 block means that for every three P waves, two get blocked and only one gets through to create a single QRS complex 1.

SECOND DEGREE HEART BLOCK

It’s a Second because only Some of the P waves are conducted through. This degree comes in 2 flavors. The first type has a lengthening PR interval (You’d think a PQ interval but often there aren’t Q waves and there are more often R waves) until one finally drops. The PR interval is progressively lengthening as though it were giving you warning until it eventually drops the QRS. This give us time to figure out what to do… as in time to follow up with cardiology it the patient is not symptomatic. This is in contrast to the type II where the QRS suddenly drops off without warning and therefore needs something done immediately1.

PEARL: The difference between Mobitz Type I and Type II: A QRS that gets progressively longer and then drops (Mobitz Type I aka Wenckebach) is not as bad as one that just drops suddenly (Type II)

MOBITZ TYPE I (Wenckebach)

Let’s start with Mobitz Type I (or the Wenckebach phenomenon). Here the P-P interval is constant but R-R intervals shorten between each complex in a group. Note that these rhythms exhibit a grouped appearance. The groupings can occur at any conduction ratios. However, there will always be one less QRS complex than there are P waves. The first PR interval is the shortest. The longest PR interval is the last one. The key to this diagnosis is the lengthening PR 1.

PEARL: The key to diagnosing Type I Block is a changing PR interval

MOBITZ TYPE II

Simply stated, Mobitz II second-degree AVB is diagnosed when you have non-conducted P waves with constant PR intervals. In Mobitz II, the QRS complexes can either be narrow or wide, depending on the location of the conduction block. However, since Mobitz II rarely occurs in the AV node the QRS complexes in Mobitz II are usually wide.

PEARL: Mobitz II has a CONSTANT PR Interval and will often have a wide complex QRS

BLOCKED PAC vs MOBITZ II

Sometime PAC’s are present and then are blocked from depolarizing the ventricles for whatever reason. The net result is that the P wave will be visible, but the QRS complex will not be. This may resemble a Mobitz II block if not thought out. Remember, the P-P interval in Mobitz II is very, very regular. If you see a prematurely occurring P wave that is blocked and the P-P interval is not the same, think blocked PAC 1.

PEARL: A blocked PAC can be differentiated by measuring the PR interval

HEART BLOCK IN AMI

This is an important distinction. In a patient with an acute MI, type I AV block usually accompanies inferior infarction (especially if a right ventricular infarct occurs). This however is transient and does not require temporary pacing. Conversely when a type II AV block occurs in the setting of acute anterior MI, this will require temporary or permanent pacing, and is associated with high mortality2.

PEARL: TYPE II BLOCK IS ALWAYS WORSE THAN TYPE I ESPECIALLY IN AMI

COMPLETE HEART BLOCK

This lack of conduction is typically due to a defect in the (infra-nodal) ventricular electrical conduction system. Therefore, there must be TWO separate pacemakers. This is why it is said that the P’s and QRS’s march out but aren’t related. One pacemaker is supraventricular (sinus, or atrial). The other is ventricular and is mandatory in order to maintain cardiac output1. On the ECG you will see, constant P-P intervals (supraventricular pacemaker) and constant R-R intervals (ventricular pacemaker). The difference is that the PR interval is completely changing and never exactly repeats throughout the entire strip. The morphology of the final rhythm will depend on the two individual rhythms that make it up. The rate of the ventricular rhythm will depend on location of the pacemaker. A junctional pacemaker will typically have narrow QRS complexes that are between 40 and 60 BPM. A ventricular pacemaker will typically have wide QRS complexes and a rate between 30 and 45 BPM. However, any pacemaker can have accelerated automaticity or may trigger a reentry circuit. In those cases, the ventricular rhythm may be tachycardia 1.

Complete Heart Block (CHB) vs AV Dissociation (AVD)

The difference between CHB and AVD is important and not just semantical. You CAN have AVD without CHB, but not vice versa.

In CHB none of the atrial beats are conducted to the ventricles. Furthermore, because the problem in CHB is usually infra-nodal you should see wide complexes and the pacemaker rate should only be idioventricular or junctional. Therefore, the atrial rate should be much faster than the ventricular rate. CHB: because of two separate pacemakers one in the atria and one in the ventricle there should be constant P-P intervals and R-R intervals but a varying P-R interval.

Conversely, in AVD you will have the occasional conducted beat even though the atria and ventricles frequently still beat independent of each other. In AVD you will likely have narrow QRS complexes with changing morphologies.  Additionally, since conduction across the AV node is still possible, you may have the ventricular rate the same or faster than the atrial rate. Lastly in AVD the P-P and R-R intervals may be not exactly constant because of conducted escape beats that skew the timing.

PEARL: AVD can be distinguished on the ECG from CHB by finding conducted P waves, a ventricular rate at least as fast as the atrial rate, and possibly varying QRS morphologies.

 FINAL PEARL: CHB IS VERY SYMPTOMATIC AND ALMOST ALWAYS HAS LOW BLOOD PRESSURE AND BRADYCARDIA

BACK TO OUR ECG EXPLANATION:

AVD annotated answer

In our ECG we see P wave (BLUE ARROW) that appears to be conducted. We see an R-R interval (YELLOW) and P-P interval (RED) that is slightly different after the conducted P waves (YELLOW VS RED). We also see a ventricular rate that is similar or faster than atrial rate. Finally, when looking at the monitor (not shown here) the patient had converted back to sinus.

SUMMARY TABLE

Complete Heart Block

(a condition like influenza)

AV dissociation

(a symptom like fever)

Definition All atrial impulses blocked Ventricle is “separated” from atria by a different focus arising from AV junction or ventricle
Clinical Findings Bradycardia

JVP with cannon a waves

No Response to atropine or exertion

Occurs at any HR

Response to atropine or exertion.

Converts to sinus

Atrial vs Ventricular Rate High/Low Equal or Low/High

REFERENCES

  1. Garcia, T. B. Introduction To 12-Lead ECG: The Art Of Interpretation (Garcia, Introduction to 12-Lead ECG) (Jones & Bartlett Learning, 2002).
  2. MD, D. P. Z., PhD, P. L. M. D., MS, R. O. B. M. D., MD, D. L. M. & MD, G. F. T. Braunwald’s Heart Disease: A Textbook of Cardiovascular Medicine, 2-Volume Set, 11e (Elsevier, 2018).