Credit to Keith Ozaki who is co-originator of this information

Apropos discussion of elective vs urgent/emergent cases. – Our program does on average 9-10 cases per day, 1-2 thrombectomies, 2-4 fistulograms with angioplasty that were on the verge of thrombosis, 1-2 tunneled catheter procedures, and the rest more or less elective stuff (not so urgent fistulogram stenoses, central vein recanalization, hand pain [depending on degree of pain may be urgent], etc.).

Our concern has been that we cannot distinguish without patient contact which of the fistulogram referrals are urgent/emergent versus relatively elective. We find that if a dialysis unit thinks there is a problem there usually is a very advanced problem and we know that we cannot deal with 5-6 thrombectomies every day.

For this reason we have made almost all referral indications “high priority” (see pasted below), similary for OR procedures. – We also have access to two procedure rooms and designated one of the rooms a Covid-19-+ve space to brings patients directly into the room, improve staff/provider adherence with PPE policies, and facilitate room cleaning/air exchange [the latter is an overkill policy by hospital that will likely fall by the wayside, it holds true for TB/airborne, but should not apply to Corono/droplet]. – Lastly, all consents are done verbally.

The experience in Asian and Europe suggest a 40-50 days curve without flattening and something (much) longer with flattening. So our question is “Can this access problem wait for 3 months or not?”. Most interventions buy at least 3 months time, so anything we can do now prevents an emergency procedure during a period when everybody is sick, staff is out, providers are cross-covering.

Baseline assumptions:

1. There will be more Covid19 exposed / infected (:= Covid19+) dialysis patients than hospitals can manage to dialyze as inpatients (so admitting all of these patients is unlikely to be a solution)
2. Consequently, some Covid19+ dialysis patients will dialyze in the community, possibly dedicated HD units, and will look for dialysis access care in the usual way
3. There will be a subset of Covid19+ dialysis patients who will require dialysis at hospital after an emergency access procedure due to volume/hyperkalemia/scheduling issues, 20-33% of thrombectomy patients seems a reasonable estimate
4. We will not decline care for Covid19+ patients
5. Care may return to “normal” in 3 months (40-50 days for rise and fall of cases with a tail)

Process of care questions:

1. Is there a way to create/dedicate “isolated” pre-post-evaluation/monitoring space? 
2. What are room cleaning and air exchange requirements after a Covid19+ case?
3. Can procedural space be dedicated to Covid19+ patients?
4. Timing of Covid19+ cases during the day to allow for cleaning procedure if dedicated space limited?
5. Where will Covid19+ outpatients receive emergency post-procedure dialysis ?
6. How is EMS and The Ride handling Covid19+ patients?
7. Will the waiting room be able to accommodate Covid19+ patients in a safe way? If not, what space is available for Covid19+ patients to wait?

Triage Process for Dialysis Access procedures - Endovascular

High Priority (access := fistula/graft/PD catheter/tunneled hemodialysis catheter that are used for dialysis):

1. Outpatient thrombectomies without other access
2. Outpatient bleeding access
3. Outpatient access with clinical/laboratory signs of extreme dysfunction or inability to use
4. Outpatient access with signs and symptoms of cardiac strain, limb ischemia and impending tissue loss (high flow)
5. New initiations with volume or electrolyte emergencies/urgencies
6. AKI in ICU/floor with need for dialysis
7. Outpatient access with new onset arm edema jeopardizing use of access or incapacitating limb use/movement
8. Inpatients thrombectomies
9. Inpatients access dysfunction (may not be as extreme as above) if this keeps patient in hospital
10. Outpatient access, not in use, with impending signs of occlusion
11. Catheter removals (as long as staff and resources available, to prevent infections during time when staff and resources are overwhelmed)
12. Venograms for access creation on specific urging of nephrologist when surgery is also pressing ahead (See Open Surgery HD Access Cases Performance Plan)

Low Priority:

1. Venograms for access placement (occasionally they may be necessary to guide urgent/emergent revision of a dysfunction/non-functional access)
2. Scheduled follow-up exams – institute enhanced screening by phone asking specific data on access function: trend of access flow past 4-6 months, trend of clearance 4-6 months, change in bleeding after needle removal, obtain photo of access  

Open HD Access Cases Performance Plan

Joint HD access clinics will continue with individual visit review the week prior for appropriateness and opportunity for delay/virtual or phone visit

Delay these types of cases:

• New HD access placement in stable, minimally to asymptomatic patients with eGFR of >15
• Permanent HD access placement in patient with functioning catheters and no known issues with catheter infections, thrombotic complications
• Asymptomatic non-used fistula ligation
• Asymptomatic AV access aneurysms without threatening signs (large thrombus, thin skin, etc.)
• Difficult augmentation/cannulation in patient without ESRD

Continue with example cases below:

• Thrombosed/failing access unable to be managed by endovascular approach
• Steal syndrome
• High flow access with complications such as Bleeding, CHF, Steal
• Infection
• Difficult augmentation/cannulation in patient with catheter in place
• Failure to mature with impending access loss
• Procedures requested for expedited care by referring nephrologist
• Inpatients in which access procedure will expedite patient progression
• Tunneled hemodialysis catheter placement or exchange that otherwise cannot be accommodated

To be reviewed real time for iterative as needed modifications

As I mentioned in a previous post, I became enthused about early cannulation grafts because they let me revise or replace a failing access without needing an interval catheter. Then I started using them primarily, first Flixene, then Acuseal when Flixene went into a prolonged backorder situation. Over a ten year period, I put in several hundred of each. Recently, I became concerned about an abnormal rate of repeat thrombosis in relatively new Acuseal grafts. I no longer use them.

Here, I have images of a graft placed in April 2018, and replaced with a Flixene graft (no catheter) this month, lasting less than 2 years. Ironically, her first graft was a Flixene, placed in 2012, and replaced in 2018 with the Acuseal. I took segments out during this last transition because I wanted to know why the Acuseal did not last as long as the Flixene. In one image, fibrosis in the zone of frequent cannulation pushes a partly disrupted silicone layer further into the lumen. In the other, the graft wall is fairly well preserved, but the lumen is full of an amorphous hyaline material, also present in the other image. I don't see many sectioned dialysis grafts, but I have never seen this kind of hyaline material in a newer graft, and especially not where the graft has not experienced heavy use. Remember that these graft segments were running and not thrombosed when they were excised and replaced. Any ideas? I will be reviewing this with a pathologist this week, and may have better images then. The specimens have been preserved if there is an interest.

I will be doing a retrospective review of the Acuseal versus the Flixene, perhaps with a standard PTFE, and a BVT group as well.

https://sites.google.com/site/abigailsarticles/special-edition-january-articles

Brief background: I have been a full-time vascular access surgeon for 20 years, placing grafts, creating fistulas, and performing endovascular maintenance and rescue, including declots. I am a big fan of early cannulation grafts, and have used them frequently since 2011, first Flixene, then after 2015, Acuseal, without major problems. However, in July of 2019 I noticed an unexplained rise in thrombotic events in patients with relatively newly placed grafts, along with some imaging suggesting delamination of the inner PTFE layer of the Acuseal graft. The middle layer of silicone is both ultrasound and radiolucent, and the inner layer of PTFE is quite thin, so imaging is difficult. The only remedy I have found is a covered stent in the zones of cannulation (Fluency). I have stopped using this graft.

Has anyone else had these problems with Acuseal grafts? Are there any insights to share?

A patient on hemodialysis three times a week visited the emergency room

The patient complained of dyspnea and chest x-ray showed cardiomegaly.

Vascular ultrasound was performed on suspicion of vascular access thrombosis.

Radiocephalic fistula had no thrill.

The attached image is an ultrasound examination performed at admission.

The ultrasound waveform is thought to be somewhat different from that of general thrombosis.

In conclusion, the patient underwent pericardiocentesis as an emergency after diagnosis with

acute cardiac tamponade.

I wonder if the shape of the ultrasonic waveform of the attached file is related to the cardiac

tamponade.

Thank you.