Transcript Slide 1

Vascular Access
Laurie Vinci RN, BSN, CNN
September 17, 2011
OBJECTIVES
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Discuss vascular access options
Describe essential components for
vascular access assessment
Discuss vascular access complications
and appropriate interventions
A Patient’s Survival
Depends on Proper
Functioning
of His Lifeline
Vascular Access Options
Arteriovenous Fistula (AVF)- Surgically created
connection between an artery and a vein
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Arteriovenous Graft (AVG)-Synthetic or biologic material
implanted subcutaneously and interposed between an artery and a vein
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Tunneled cuffed catheter
Non-tunneled, non-cuffed catheter
A-V Fistula First Breakthrough
Initiative (FFBI)
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Objective: To ensure that people receiving
hemodialysis be given the opportunity to be
evaluated for an AVF first
A functional fistula is the goal, not the insertion of
a fistula with a poor chance at maturing
In April 2005, the CMS announced that all dialysis
units improve AVF prevalence rates to 66% by end
of 2009
Diagnostic Evaluation in
in Preparation for an Access
Preferred method: Duplex ultrasound mapping of
the upper extremity arteries and veins for all patients
 To evaluate central veins:
1) Duplex Ultrasound
2) Venography
3) Magnetic Resonance Angiography (MRA)
Should be done on patients with pacemakers or prior
catheters
NKF KDOQ, 2006, CPG 2
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AVF placement in order of priority
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A wrist (radiocephalic) primary fistula
An elbow (brachiocehalic) primary
fistula
A transposed brachial basilic vein fistula
NKF KDOQI, 2006, CPG 2
Advantages of the AVF
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Lowest rate of thrombosis, require the fewest
interventions, longer survival of the access
Lower rates of infections than AVG/Catheters
Associated with increased survival and lower
hospitalization rates
Cost of implantation and access maintenance are the
lowest long term
Outflow veins are autogenous tissue which seals and
heals after cannulation. Synthetic grafts only seal by
means of a fibrin plug.
Can utilize the buttonhole cannulation technique
Disadvantages of the AVF
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Vein may fail to enlarge or increase wall thickness
Long maturation times: weeks to months following
creation of AVF before they can be used
In some, the vein may be more difficult to cannulate
than an AVG
Thrombosed AVF may be more difficult in which to
restore flow
The enlarged vein may be visible and perceived as
cosmetically unattractive by some individuals
Potential for a “steal syndrome” in patients with
compromised peripheral vasculature
Arteriovenous Graft (AVG)
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1) Forearm loop graft, preferable to a straight
configuration
2) Upper arm graft
3) Chest wall or “necklace” prosthetic graft or lower
extremity fistula or graft (all upper-arm sites should
be exhausted)
Advantages of the AVG
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Large surface area for cannulation
Technically easier to cannulate than new AVFs
ePTFE grafts: No less than 14 days, ideally 3-6 weeks
before cannulation to allow healing of incision and
resolution of pain and swelling
Placed in many areas of the body
Variety of shapes to facilitate cannulation
Easier for surgeon to handle, implant, and construct
the vascular anastomoses
Disadvantages of the AVG
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Increased incidence of thrombosis and
infection over an AVF
Patients have a higher mortality risk than
those dialyzed with an AVF
Shorter patency rates than an AVF
Cannulation sites seal but do not heal
Potential for allergic response
May cause “steal syndrome” if compromised
peripheral vasculature
Assessment of AVF or AVG
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Assess access vessel:
1) Redness, bruising, hematoma, rash or
break in skin, bleeding, exudate, atypical
warmth, tenderness/pain, aneurysm or
pseudoaneurysm
2) Maturation of the vessel, direction and
characteristics of the flow (thrill), auscultate
for bruit noting changes in pitch
3) Identify cannulation patterns: rotation of
site, presence of buttonholes
Cannulation of AVF and AVG
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Confirm direction of blood flow
Select sites away from recent entries
Arterial needle (pull) can be against the flow
(retrograde) or with the flow (antegrade)
Venous needle (return) always with the flow
and above the arterial needle
Never cannulate into anastomoses,
aneurysms, or pseudoaneurysms
USE ASEPTIC TECHNIQUE
Cannulation AVF and AVG
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For AVG cannulation: Angle of needle insertion is
approximately 45 degrees. First cannulation can be 2
weeks post-op for most grafts using needles of the
standard size.
For AVF cannulation: Always use a tourniquet.
Angle of insertion is approximately 25 degrees.
Rotate sites using ROPE LADDER TECHNIQUE or
buttonhole cannulation
First cannulation of newly matured AVF: if
functioning catheter, use a #17 ga. needle for
arterial pull and venous return via catheter.
Do not “flip” needles. This risks cutting or coring the
endothelium of the vessel
Post dialysis AVF/AVG
Care
Remove needles at same angle as entry, use needle safety device
and discard into sharps container immediately
Compress with 2 fingers following complete removal of the
needle to prevent pain and damage to the vessel
Optimal to remove one needle at a time. Clamps should be used
only if there is no alternative (one site at a time)
Do not occlude blood flow in peripheral access, check thrill distal
to site of pressure
Sites can be dressed with adhesive bandage, guaze, and tape but
should never be circumferential nor tight
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AVF: INFECTION/INTERVENTIONS
Rare, but most often occur at cannulation site
Should be treated as a subacute bacterial endocarditis
with 6 weeks of antibiotic therapy
 Avoid cannulation at the infected site and rest arm
 Take blood/wound cultures, then initiate antibiotic
therapy with broad spectrum Vancomycin plus an
aminoglycoside
 Convert to appropriate antibiotic upon culture results
 Fistula surgical excision in cases of septic emboli
NKF KDOQI, 2006, CPG 5
INFILTRATION: AVF/AVG
INTERVENTIONS
Pain and swelling (hematoma) at time of cannulation or during the
dialysis treatment. On dialysis: low arterial pressure alarm may
indicate arterial needle infiltration, high venous pressure
alarm may indicate venous needle infiltration
At time of cannulation: remove needle, hold firm pressure until
bleeding stops and apply ice. If hematoma is large, ice pack x 15
mins. before trying site again. If venous needle, cannulate above
site to avoid feeding into infiltrated area.
On dialysis: blood pump off, insert another needle, leave original
needle in place unless hematoma enlarges, apply ice to area of
infiltration
Instruct patient on application of ice intermittently for first 24 hrs.,
then warm compresses
AVF/AVG STENOSIS
Findings indicative of a stenosis:
Decreased flows, increased pressures, arm edema
Central vessel stenosis: breast, neck, chest, face swelling
Appearance of collateral veins
AVF does not collapsed with arm elevation
Increase in post dialysis bleeding time
Difficulty with cannulation
Pain
Altered characteristic of thrill or bruit
Recent pseudoaneurysm formation in AVG
AVF/AVG STENOSIS
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Underdialysis can be minimized or avoided and the rate of
thrombosis reduced via access monitoring and surveillance for
vascular access stenosis
Interventions
Doppler ultrasound or Fistulogram to measure flow and detect
stenosis
Treatment for hemodynamically significant stenosis (> 50%) is
balloon angioplasty. Stenting is sometimes warranted.
Follow-up fistulograms may be scheduled.
Depending on fistulogram findings, surgical revision may be
necessary
Venous hypertension: arm elevation above level of heart
Nontunneled, Noncuffed
Acute Catheters
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Can be inserted at the bedside, only in hospitalized
patients and used for no more than one week
Catheter tips should be in the superior vena cava
(SVC); confirmed by CXR or fluoroscopy at time of
placement
Uncuffed femerol catheter should only be used in
bed-bound patients , left in place for no more than 5
days. Highest infection rates
NKF KDOQI, 2006,CPG 2
Tunneled, Cuffed Catheters
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Long term use only in patients:
1) not suitable for AVF or AVG
2) has AVF or AVG planned
3) AVG or AVG waiting to mature
4) waiting for scheduled live donor transplant
Preferred site is right internal jugular vein: more
direct route to right atrium and lower risk of
complication compared to other sites
Other options: Rt. External jugular, Lt. internal and
external jugular veins, subclavien veins, femerol
veins, translumbar and transhepatic access to IVC
Should not be placed on same side as maturing
AV access
Tunneled, Cuffed Catheters
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Ultrasound guidance and fluoroscopy
used for placement of the catheter
Tip of the catheter should be in right
mid-atrium
Fibrous cuff, about 1 cm from exit site
inside tunnel; designed to create a
barrier to organism entry and prevent
catheter dislodgement
Advantages of Tunneled, Cuffed Catheters
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Can be inserted into multiple sites
relatively easy
No maturation time, can be used
immediately
Cause no changes in cardiac output or
myocardial load
Provides access for months permitting
AVF maturation
Disadvantages of Tunneled Cuffed Catheters
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High morbidity due to thrombosis and
infection
Risk of central venous stenosis or occlusion
Frequent episodes of occluded catheters due
to thrombosis or fibrin sheaths:
1) lytic agent or interventional procedure
2) leads to reduced dialysis adequacy
associated with increased morbidity and
mortality
Catheter
Assessment
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Absence of:
1) Facial/neck edema, respiratory distress, cardiac
arrhythmia
2) Catheter occlusion: inability to withdraw
anticoagulant and blood
3) Fibrin sheath with tail blocking the tip holes:
ability to push saline but inability to pull
4) Integrity of the catheter, well healed exit site:
absence of redness, swelling, discoloration, drainage,
bleeding or catheter migration such as a visible cuff
INFILTRATION: AVF/AVG
INTERVENTIONS
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If new access and patient has a catheter
access, do not recannulate till swelling has
receded
If unable to clearly feel or see the vessel, the
patient has no catheter and needs dialysis:
consider use of short-term catheter
REMEMBER TO MAINTAIN VISIBILITY OF THE
ACCESS AND CONNECTIONS AT ALL TIMES
CATHETER (CVC) DYSFUNCTION
Dysfunction defined as failure to attain and maintain
blood flow rate of 300ml/min or greater at a prepump
arterial pressure less than -250 mmHg.
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Signs of CVC dysfunction: low arterial pressure alarms and
high venous pressure readings (greater then 250 mmHg)
limiting blood flow rates which are not responsive to patient
repositioning or catheter flushing, unable to aspirate blood
freely
Causes: Mechanical (kinks or dislodgement), misplaced
sutures, catheter migration, drug precipitation, patient position,
catheter integrity, holes/cracks, partial or complete occlusion
due to a thrombus or fibrin sheath
NKF KDOQI, 2006, CPG 7
CATHETER (CVC) DYSFUNCTION
INTERVENTIONS
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Check for and correct mechanical obstruction such as
kinking of catheter, lines or clamp indentation
Check for dislodgement evidenced by cuff extrusion
Tape in place and report to vascular team
Reposition the patient: supine returns the patient to
the position when the catheter was inserted, may
reposition tip of catheter in Rt. atrium. Central veins
also maximally engorged in this position. Change
position of the head or have the patient cough
CATHETER (CVC) DYFUNCTION
INTERVENTIONS
Flush each lumen with 10 ml of normal saline
 Reverse lines using aseptic technique
 If flow problem persists, likely thrombus in lumens,
on the wall of the vessel or a fibrin sheath. Use
thrombolytic agent per MD order
 May need to change the catheter
All catheters “locked” with some anticoagulant
to prevent thrombus. Firmly infuse to the
volume of the lumens, then quickly reclamp
lumen to prevent negative pressure in catheter
pulling blood in the side holes.
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