It's interesting that one of the friendlier sisters asked "are you still here doc? Not finished yet?" Well, I'm not the only one who thinks this thing is taking forever. Thank God.
Today is also my eldest sons birthday. Nearing the end of October so I have less than two months to go and the pressure is on. That's a good thing because before this it was getting a bit difficult to make myself move. Now its internal motivation (ok la, external, who am I kidding, dateline is getting closer).
The logbook sort of starts with vascular access so tonight will try to cover the lecture notes on this topic.
Care of AV Grafts and Hemodialysis Catheters
Dr. Yudisthra M. Ganeshadeva MBBS (Mal), MRCP (UK and London), Fellowship in Nephrology (Malaysia)
AV Grafts
What is an AV Graft?
•A Synthetic Tube used to connect an artery to a Vein •Usually made of PTFE or Dacron •Used primarily as access in patients with difficult veins
Surgical Placement
•Can be placed on –Forearm (Forearm loop graft) –Arm –Neck (Necklace graft) –AxilaryArtery to Femoral Vein •The longer the graft –the less likely it is to last.
Time to Maturation
•AV Grafts are usually ready to use within 2-4 weeks from placement •May be used earlier if not much soft tissue swelling.
Determining the Direction of Flow AV Grafts
•Compress the graft in the middle with 2 fingers –milk it both ways with pressure •Release one finger •If the graft fills up again-the limb proximal to that finger is the arterial end.
Determining the Direction of Flow AV Grafts
•Ultrasound technique -can also use dopplerto look at flow •Most surgeons include a diagram
Post Operative Care of AV Graft
•Patient advice –If bleeding –pressure with gauze/kleenexfor 10 mins –Do not get wound soaked or wet for a week post op –Check operation site for redness, swelling, discharge or warmth which may signify infection –First week –need to keep arm elevated above level of heart to minimise
swelling.
Chronic Care of AV Graft
•Avoid on the side of the graft –Taking Blood Pressure –Taking Blood tests •Thrill should be palpable on working AV Grafts
Cannulation of AV Grafts
•Staff : –If hands are visibly soiled, use soap and water. –If not visibly soiled, use an alcohol-based hand rub or soap and water. –Decontaminate hands before and after patient contact, rubbing hands together vigorously for 15 seconds then rinsing. –Staff members who closely follow the policies and procedures of their respective facilities will always use and change gloves when indicated.
Cannulation of AV Grafts
•It is important not to try to cannulate the same site with each treatment as this weakens the access wall –puncture graft in step ladder fashion.
•Patient: It is recommended that patients wash their site arm carefully with soap and water when arriving at dialysis..
Cannulation of AV Graft
•Skin prep –for grafts, best to wash graft arm with non drying soap and water first before skin prep with povidone/chlorhexidine. •Skin pulled taut in opposite direction to needle •Needle inserted at 45 degree angle –once in rotated 180 degrees so that cutting edge faces downwards •Taped in angle of insertion
Removal of needle
•Needle pulled out –then pressure applied to puncture site. •Do not apply pressure before needle removed.
Care of Hemodialysis Catheters
Anatomy of the Neck •The internal jugular is the preferred site of cannulationfor insertion of hemodialysis catheters.
•The Right internal jugular offers a straight path to the atrium.
•The left internal jugular has a more tortuous path
Final Position of the catheter in the right artium
Ultrasound Guidance
•Ultrasound guidance is mandatory cannulationof the internal jugular veins due to markedly variable anatomy. •Realtimeultrasound guidance preferred.
Lin, BS, Huang, TP, Tang, GJ, et al. Ultrasound-guided cannulationof the internal jugular vein for dialysis vascular access in uremicpatients. Nephron1998; 78:423.190 patients undergoing percutaneousinsertion of a temporary catheter into the internal jugular vein compared the complication rates among those using ultrasound-guided placement (104 patients) to those using landmarkguided insertion (86 patients). Significantly superior results were obtained with ultrasound guidance with respect to overall success rate (99 versus 86 percent, P<0 .01="" 11.6="" 2.58="" 35="" and="" attempt="" complication="" first="" of="" p="0.015). </div" percent="" puncture="" rate="" success="" the="" traumatic="" trials="" versus="">
Anatomy of The SubclavianVein
•The subclavian anatomy is more fixed than that of the internal jugular vein.
•Higher risk of pneumothorax as well as bleeding and hemothorax as a result of this being a non compressible site.
•Subclavian cannulation can result in brachiocephalic stenosis on the ipsilateral site obviating the possibility of successful fistula creation on the arm on the same side.
Catheter Care
Care of the Catheter-Patient Info
•No showers for the first 24 hours. •Showers requires catheter and dressing to be wrapped with plastic wrap. •If the catheter comes off –compress the insertion point with a finger until bleeding stops.
Handling the Catheter
•Hemodialysis catheter dressing changes and catheter manipulations that access the patient’s bloodstream should only be performed by trained dialysis staff. •The catheter exit site should be examined at each hemodialysis treatment for signs of infection. •Catheter exit site dressings should be changed at each hemodialysis treatment
Handling the Catheter
•Use of dry gauze dressing combined with skin disinfection, using either chlorhexidine or povidone iodine solution, followed by povidone iodine ointment or mupirocin ointment at the catheter exit site are recommended after catheter placement and at the end of each dialysis session. •Manipulating a catheter and accessing the patient’s bloodstream should be performed in a manner that minimizes contamination.
Decontaminating the Catheter
•Dressing for the catheter at each visit •Povidone soak/ Chlorhexidine soak for hubs prior to dialysis procedure.
Decontamination procedure
•Catheter hubs should be soaked for 3-5 minsin povidoneiodine and allowed to dry prior to seperation •Catheter lumens should be kept sterile. •Catheter tips should remain capped or attached to a syringe while maintaining a clean field. •Patients should wear a mask for all catheter procedures •Dialysis staff should wear a mask and gloves for any procedure related to the catheter. •Gloves need to be changed for each patient.
Other infection prevention methods
•Do not recycle blood lines. •Keep the dialysis unit clean.
Troubleshooting AV Grafts and Fistulas
When to Refer Infected AV Graft
AV Graft Infection –May present with following over graft •Pus •Inflammation •New Onset Pain •Needs inpatient intravenous antibiotics ±debridement/ removal of part or all of graft.
When to refer Graft Thrombosis
•Graft thrombosis is common –no thrill over graft, graft hardened & unable to use for dialysis. •Need to refer early to salvage graft-best to return to surgeon who created graft. •Graft salvage may be done endovascularly or through surgery
When to refer Graft Hematoma
•Graft hematomascan occur due to tears of the graft during needling. •Usually resolve spontaneously •AV graft different from vessels as tears in material cannot seal off.
When to Refer Graft Pseudoaneurysm
•Present with localised pain and swelling. •Pulsatile–external to graft •Usually due to poor needling technique. •Will require referral for repair of graft –if numerous or large. •Avoid areas of pseudoaneurysm for cannulation.
When to refer Infection of AV Grafts •Characterised by –Redness –Pus –Skin Erosion –Exposure of the graft •Associated with –Tenderness over graft –Fever –±fluctuance
When to refer Infection of Grafts
•Entire graft should be removed in the following conditions: –the graft is less than one month old, –graft involvement by infection is extensive and graft infection is accompanied by sepsis or hemorrhage.
When to refer Dialysis Associated Steal Syndrome
•DASS occurs in 2.78% of PTFE grafts. •Subjectively coldness, numbness, tingling, and impairment of motor function (not limited by postoperative pain) •Objectively –Cold peripheries, decreased sensation.
When to refer Dialysis Associated Steal Syndrome
•Left untreated –potential of gangrene •Usually needs surgical procedure to reduce steal by cutting down arterial inflow. •In grafts may occur immediately post surgery when compared to AV fistula where steal may develop over time.
Troubleshooting Hemodialysis Catheters
Immediate Problems
Hematoma
•Hematomascan arise from tears in the jugular vein wall or from punctures into the carotid artery. •Hematomarisk is higher in patients with coagulopathies and uraemia.
Management
•Usually conservative •Cold compress at site of hematoma may help.
Carotid Artery Puncture
•Carotid artery punctures can result in dissection of the artery and formation of pseudoaneurysms •May require placement of covered stentif large or can be filled in with coils
Carotid Artery Dissection
•Carotid artery dissection is as a result of traumatic accidental puncture of the carotid artery and can even result in strokes as well as bleeding.
Carotidojugular Fistulas
•Carotidojugular fistulas can result from the accidental puncture of the carotid and jugular at the same insertion.
•They are usually significant if a dilator or catheter has been passed from the carotid into the jugular or vice versa.
•Treatment can be conservative if the fistula is small –may seal up spontaneously
•Covered endovascular stentmay be needed in some patients where the fistula is large.
•Stent placement will require patients to be on clopidrogrelfor 3 months and aspirin for life.
Pneumothorax
•Rare but dreaded complication of catheter insertion. •More common with subclavian catheters •Usually present within minutes or hours of insertion
Hemothorax
•Can occur with catheter insertion. •Usually accompanied by fall in blood pressure, pallor, tachycardia and difficulty breathing •Can occur within hours to days of catheter insertion
Arrythmias
•Ventricular arrythmiascan arise from catheters placed deep in the ventricles and can be fatal if not identified and terminated immeadiately.
•They can also arise from guidewiresthat irritate the ventricular myocardium
Chronic Problems Flow Issues
Troubleshooting HD Catheters
•Poor flow Red Lumen –May be due to sideholes resting against vessel wall – usually in a narrowed vessel –May be due to intravascular Sheath formation –this is a fibrinous sock that covers the catheter.
•Carotid artery punctures can result in dissection of the artery and formation of pseudoaneurysms •May require placement of covered stentif large or can be filled in with coils
Carotid Artery Dissection
•Carotid artery dissection is as a result of traumatic accidental puncture of the carotid artery and can even result in strokes as well as bleeding.
Carotidojugular Fistulas
•Carotidojugular fistulas can result from the accidental puncture of the carotid and jugular at the same insertion.
•They are usually significant if a dilator or catheter has been passed from the carotid into the jugular or vice versa.
•Treatment can be conservative if the fistula is small –may seal up spontaneously
•Covered endovascular stentmay be needed in some patients where the fistula is large.
•Stent placement will require patients to be on clopidrogrelfor 3 months and aspirin for life.
Pneumothorax
•Rare but dreaded complication of catheter insertion. •More common with subclavian catheters •Usually present within minutes or hours of insertion
Hemothorax
•Can occur with catheter insertion. •Usually accompanied by fall in blood pressure, pallor, tachycardia and difficulty breathing •Can occur within hours to days of catheter insertion
Arrythmias
•Ventricular arrythmiascan arise from catheters placed deep in the ventricles and can be fatal if not identified and terminated immeadiately.
•They can also arise from guidewiresthat irritate the ventricular myocardium
Chronic Problems Flow Issues
Troubleshooting HD Catheters
•Poor flow Red Lumen –May be due to sideholes resting against vessel wall – usually in a narrowed vessel –May be due to intravascular Sheath formation –this is a fibrinous sock that covers the catheter.
Troubleshooting HD Catheters
•Poor flow Blue Lumen –May be due to position of catheter tip –May be abutting structure e.gTricuspid Valve or vessel wall (left sided catheters)
When to refer Central Vein Stenosis
•Long term HD catheter use can result in central vein stenosis. •Difficult to treat –can confound future fistula creation
•Poor flow Blue Lumen –May be due to position of catheter tip –May be abutting structure e.gTricuspid Valve or vessel wall (left sided catheters)
When To Refer Poor Flow Both or Either Lumen
•Can be due to intraluminal thrombus or external thrombus abutting openings •No flow both lumens-new catheter –May be due to catheter malposition –May have dissected through vessel wall during insertion for new catheters. –Needs Exchange
Management
•Rotate Catheter gently until flow improved. •Withdraw catheter 1-2 cm •Still no improvement? Refer –may need urokinase or intraluminal brushing if cuffed catheter •Cathetogram if new catheter or old catheter failing urokinase/intraluminal brushing.
Management
•Usually involves exchange of catheter or reposition of catheter over guidewire for non cuffed catheters.
Other Issues
When to refer Exit site bleeding •Bleeding from the sides of the catheter insertion point •May be due to crack in the Catheter •May be due to downstream stenosis •May be due to large catheter insertion wound – for new catheters •Risk of Infection
Management
•Deeper re-position of catheter for downstream stenosis –May require fluroscopy •Purse String Suture at exit site –usually first line of management
•Long term HD catheter use can result in central vein stenosis. •Difficult to treat –can confound future fistula creation
When to Refer Central Vein Stenosis
•May require plastyin the event arm having fistula is swollen and distressing to patient •May require plastyif stridoror breathing difficulty in patient.
Infections
Infections of Catheters
Exit Site Infections(ESI)
Definition:
•Localized Catheter Colonization
Significant growth of a microorganism (>15 CFU) from the catheter tip, subcutaneous segment of the catheter, or catheter hub
•Exit Site Infection
Erythema or induration within 2 cm of the catheter exit site, in the absence of concomitant bloodstream infection (BSI) and without concomitant purulence
•Clinical Exit Site Infection
Tenderness, erythema, or site induration>2 cm from the catheter site along the subcutaneous tract of a tunneled catheter, in the absence of concomitant BSI
ESI Prevention:Topicalantiobiotic
Polysporintriple antibiotic (Lok2003) –169 patients with TCD, 6 months
Mupirocin(Johnson 2002) –50 HD patients with TCD catheters, 20 months
Topical antibiotics –meta analysis
•Topical antibiotics reduced the rate of:
–Bacteremia •rate ratio, 0.22 [95% CI, 0.12 to 0.40]; •0.10 vs. 0.45 case of bacteremiaper 100 catheter-days,
–Exit-site infection •rate ratio, 0.17 [CI, 0.08 to 0.38]; •0.06 vs. 0.41 case of infection per 100 catheter-days,
–Need for catheter removal, and
–Hospitalization for infection
Tunnel Infections
•Tunnel Infection
Purulent fluid in the subcutaneous tunnel of a totally implanted intravascular catheter that might or might not be associated with spontaneous rupture and drainage or necrosis of the overlaying skin, in the absence of concomitant BSI (blood stream infection)
Blood Stream Infections
•Infusate-Related BSI
Concordant growth of the same organism from the infusate and blood cultures (preferably percutaneously drawn) with no other identifiable source of infection
•Catheter-Related BSI
Bacteremia/fungemia in a patient with an intravascular catheter with at least one positive blood culture obtained from a peripheral vein, clinical manifestations of infections (i.e., fever, chills, and/or hypotension), and no apparent source for the BSI except the catheter.
Vascular access Part 2
PATIENT ASSESSMENT
- History
- Hx of CVC (central venous catheter?)
- Arm dominance
- DM
- Physical Examination
- Venous caliber and patency
- Character of pulse
- DM
- Congestive HF
- Previous vascular access
- Previous arm, neck or chest surgery/trauma
- Anticipated renal transplant
- Allen’s test
- Scar of previous CVC placement
- Presence of collateral veins
- Signs of cardiac failure
What is a arteriovenous fistula?
DOPPS 2007
Access by Etiology of Disease
- 1st preference Radiocephalic
- 2ndpreference Brachialcephalic
- 3rd preference Brachialbasilic
DOPPS 2007
Access by Etiology of Disease
KI 2009; 76: 1040-1048 Hemodialysis Access Failure A call to action -revisited
Why a Native Fistula?
Fewer infectious complications: AVFs: 4.4 -12 x less infection rates than AVGrafts
Fewer interventional procedures to keep patency: AVFs: 2.4 -7.1 x less salvage procedures than AVGs
Better 1 year primary patency in incident HD patients: 68% for AVFs & 49% for AVGs
Lower Risk of CV deaths For patients starting AVF By 90 days of HD
Non Infected Catheters Increases Inflammation
When to Create a Fistula?
30-20-10 GFR guidelines
GFR < 30ml/min, discussions on RRT options
GFR < 20ml/min, strongly advocate placement of vascular access.
4-6 months prior to anticipated use of fistula GFR < 10ml/min, mature fistula should be ready
Role of Mapping
Vascular mapping Pulse examination Differential BP measurement Assessment of palmar arch Arterial Diameter by Dupplex Ultrasonography Arterial Diameter by Dupplex Ultrasonography
Diameter of at least 2mm a/w better success
Functional Fistulas
Rule of 6s’ Flow of at least 600ml/s Diameter of 0.6cm Depth of no more than 0.6cm (0.5-1.0cm)
Straight segment
Accessible in sitting position
Sufficient time for maturation
Mature Arteriovenous Fistula
During AVF Maturation Process
Look, listen, and feel the new AVF at every dialysis treatment
After the scar heals, begin assessing AVF using a “gentle” tourniquet placed high in the axilla area
Instruct patient to start access exercises after healing (check with surgeon first)
Document patient education as well as condition and maturation of the AVF
Fact
Experienced dialysis nurses have an 80% success rate for identifying fistula maturity.
Clinical Clarification
Several studies suggest that performing access exercises after surgery may contribute to the development of the fistula.1-3However, it is important to note that exercise alone will not turn a poor fistula into a good, functional fistula.
During Maturation
Feel for strong thrill at arterial anastomosis
Listen for continuous low-pitched bruit
Document fistula maturation, patient education
During Physical Examination
- Assess AVF for complications
- Thrombosis
- Stenosis
- Infection
- Steal syndrome
- Aneurysms
Select cannulation sites
Fistula Maturation
What diagnostic tools or techniques can be used to determine if an AVF is ready for cannulation?
Can the same tools or techniques be used to select the cannulation sites?
Diagnostic Tools/Techniques to Determine If an AVF Is Ready
- Duplex Doppler study
- Physical exam by the:
- Nephrologist
- Nephrology nurse
- Surgeon
- Angiogram (fistulogram)
Best Tool/Technique?
Physical Exam!
Look, Listen, and Feel
Use Your:
Eyes
Ears
Fingertips
Maturing Fistula Physical Exam
Firm, no longer mushy
Vessel wall thickening
Vessel diameter enlargement (to 4–6 mm)
Absence of prominent collateral veins
If in doubt, “Just Say No”
Inspection
Look for: Changes compared to opposite extremity Skin color/circulation Skin integrity Edema Edema Drainage Vessel size/cannulation areas Aneurysm Hematoma Bruising
Look for Complications
Changes in access
- Redness
- Abscess
- Infection
- Cannulation sites
Distal Areas of Access Extremity
Hands/Feet:
Cold
PainfulSteal
Changes in access extremities •Skin color •Edema •Small blue or purple veins •Hematoma •Bruising
PainfulSteal
Numb Syndrome
Fingers/Toes:
Discolored
Central or outflow vein stenosis
Stenosis
Frequent cause of early fistula failure Juxta-anastomotic stenosis most stenosis most common
26
Juxta-Anastomotic Stenoses
Most common AVF stenosis Vein segment immediately above the arterial anastomosis Stenosis also may be present in artery
Caused by Caused by ? Trauma to segment of vein mobilized and manipulated by the surgeon in creating the AVF
Observe Access Extremity for Stenosis
Before the patient has needles inserted Make a fist with access arm dependent; observe vein filling Raise access arm; entire AVF should flatten/ collapse if no stenosis/obstruction
If a segment of the AVF has not collapsed, stenosis is located at junction between collapsed and noncollapsed segment
Instruct patient to perform this at home
Infection
Lower rate with AVF compared with other access types1,2
Staphylococcusaureusthemost commonpathogen2
Patients and dialysis team personnel have high rates of Staphylococcuson skin3 Staphylococcuson skin3
Handwashing before, after, and between patients is critical4
Steal Syndrome
Shortage of blood to hand
Rare but can be serious
Regularly evaluate sensory-motor changes to hand and condition of skin, especially in diabetic patients
Aneurysm
Localized ballooning
Localized ballooning
Signs and Symptoms of Complications
Differences in extremities
Edema or changes in skin color = stenosis or infection
Access Redness, drainage, abscess = infection
Aneurysms
Aneurysms
Access extremities Small, blue/purple veins = stenosis
Discolored fingers = steal syndrome
Signs and Symptoms of Complications (cont’d)
Temperature Changes
Warmth of extremity = infection
Coldness of extremity may = steal syndrome
Thrill for Stenosis
Abrupt change or loss
Pulse-like
Narrowing of vein = stenosis
Feel for Cannulation Sites
Superficial, straight vein section
Adequate and consistent vein diameter
Palpation
Temperature Change
Warmth = possible infection
Cold = decreased blood supply
Thrill Thrill
Palpation can be started at the anastomosis
Thrill diminishes evenly along access length
Change can be felt at the site of a stenosis; becomes “pulse-like” at the site of a stenosis
Stenosis may also be identified as a narrowed area
Palpation(cont’d)
Feel for Size, Depth, Diameter,and Straightness of AVF
Feel the entire AVF from arterial anastomosis all the way up the vein
Evaluate for possible cannulation sites = superficial, straight vein section with adequate and consistent vein diameter
Auscultation Listenfor the Nature of the Bruit
Auscultation (cont’d)
Listen for Bruit Listen to entire access every treatment
Note changes in sound characteristics (bruit):
A well-functioning fistula should have a continuous, A well-functioning fistula should have a continuous, machinery-like bruit on auscultation
An obstructed (stenotic) fistula may have a discontinuous and pulse-like bruit rather than a continuous one—and also may be louder and high-pitched or “whistling”
Louder at stenosis than at anastomosis
Requirements for Cannulation
Physician order
Experienced, qualified staff person
Tourniquet
Post-Op Follow-up
Communicate assessment findings with access team, including surgeon
Check maturity progress every session
Assure evaluation by surgeon 4 weeks post-op Assure evaluation by surgeon 4 weeks post-op Intervene if there is no progress at 4 weeks or AVF is not mature and ready for cannulation at 6–8 weeks
COMPLICATIONS
Bleeding
Bleeding during treatment (oozing around needle or infiltration) = fragile vessel wall or back wall penetration; don’t flip the needles
Bleeding post–needle removal = fragile vessel wall or needle trauma or inadequate pressure at puncture sites
Review needle-removal technique. Improper pressure with needle withdrawal = vessel damage
A pattern of prolonged bleeding post–needle removal may indicate stenosis or clotting disorder. Evaluate bleeding after 20 minutes
Educate patients about post-treatment hemostasis and what to do at home should the needle site re-bleed
Infiltration = Hematoma
Prevent Cannulation Infiltrations
Don’t flip needle
Don’t lift needle in vein
Flush with NSS
Don’t flip needle
Don’t lift needle in vein
Flush with NSS
Prevent Postdialysis Infiltrations
Apply gauze without pressure
Remove needle at insertion angle
Apply pressure with 2 fingers
Hold pressure 10–12 minutes
Treating Infiltrations
Elevate arm above heart
Ice 20 minutes on/20 minutes off for 24 hours
Warm compresses after 24 hours
Let fistula rest
Second infiltration: Notify vascular access team
Don’t use AVF until directed
Infiltrations in New AVF
Elevate arm above the level of heart
While protecting the skin over access area with a clean cloth, gently apply:
Ice 20 minutes on/20 minutes off for first 24 hours
Warm compresses after 24 hours
Infiltrations in New AVF(cont’d)
If the fistula infiltrates, let it “rest” until the swelling is resolved
If the fistula infiltrates a second time, the staff should notify the vascular access team, including the surgeon, as soon as possible for intervention
Don’t use that AVF until further directed
How to Prevent Infiltrations
Check for flashback and aspirate
Flush with NSS to ensure the needle flushes with ease and there are no signs or symptoms of infiltration
Saline causes much less damage and discomfort than blood if an infiltration occurs
Post-Cannulation Bruising and Hematoma
If bruising or hematoma occurs after dialysis, the surface skin site has sealed but the needle hole in the vessel wall has not
Use 2 fingers per site for hemostasis
It is crucial to apply pressure to both the skin and access wall puncture sites
AVF Bleeding Emergency Kit for Dialysis Patients
Gauze pads to apply to the bleeding site
Tape to apply once the bleeding has stopped
Information Card:
1.Vascular access type/location
2.Name and phone number of the vascular access surgeon and address of the closest hospital, should the bleeding not stop and further assistance be required
Poor Flow
May be due to location or position of needle(s)
May need to change direction of arterial needle
If poor flow persists after next session despite changing needle locations, refer to surgeon for evaluation and possible treatment options
NOTE: Use tourniquet for cannulation only! Do not leave in place for entire treatment!!!
Aneurysm
Caused by stenosis as vessel narrowing increases “back pressure,” causing vessel distension and weakening of vessel wall
May also be caused or aggravated by frequent cannulations in the same area
Stenosis
Most common complication
Causes: IV, CVC, PICC lines
Surgery to create AVF
Aneurysms
May be caused by the back pressure associated with stenosis
Needle-stick injury
Types of Stenoses
Juxta-anastomotic (most common stenosis in AVF)
Mid-access
Outflow
Central-vein
Mid-access
Outflow
Central vessel
Central-vein Stenosis
Distended, Obstructed Left Shoulder Veins Indicative of Central-vein Stenosis
Clues to Stenosis
Clotting of the extracorporeal circuit 2 or more times/month
Persistently swollen access extremity
Changes in bruit or thrill (ie, becomes pulse-like)
Difficult needle placement
Blood squirts out during cannulation
Elevated venous pressures
Clues to Stenosis (cont’d)
Excessively negative pre-pump AP
Decreased blood pump speeds
Inability to achieve BFR
Changes in Kt/V and URR
Recirculation
Prolonged postdialysis bleeding
Frequent episodes of access thrombosis
Observe Access Extremity for Evidence of Stenosis
Perform a physical exam for AVF stenosis Perform before patient has needles inserted Have patient keep access arm dependent and make a fist—observe vein filling Have patient slowly raise the access arm—the entire AVF should collapse if no stenosis; if entire vein is not flat, indicative of stenosis If a segment of the AVF has not collapsed, stenosis is located at junction between collapsed and noncollapsed segment Patient can do this at home
Thrombosis
Surgical/technical problems
Preexisting anatomic lesions (eg, old IV injury)
Premature use
Poor blood flow
Hypotension
Hypercoagulation
Fistula compression
Infection
AV fistulas have lowest risk of infection of any vascular access type.
However… Each pre-and post-treatment exam should include:
Checking for signs/symptoms of infection, including:
Changes of skin over access area
Redness
Increase in temperature
Swelling,
hardness
Drainage from incision, needle sites
Tenderness or pain
Patient complaints without other indications of Malaise Fever
Prevention of Infection
Prevention General hygiene
Pretreatment washing of access extremity
Hand washing, before and after cannulation
No scratching, irritation of skin of access extremity
Precannulation
Appropriate skin antisepsis
Sufficient antiseptic-skin contact time
Cannulate while antiseptic is wet or dry, as directed
Cannulation
Maintain needle sterility
Do not cannulate through scabs or abraded areas
Steal Syndrome/Ischemia
Steal syndrome is a constellation of symptoms related to ischemia (inadequate blood supply to the hand) caused by the AVF “stealing” blood away from the extremity
Steal causes hypoxia (lack of oxygen) to the tissues of the hand, resulting in severe pain and identified by nail bed discoloration, a cool hand, and a weak or absent pulse hand, and a weak or absent pulse
Neurological and soft tissue damage to the hand can occur, resulting in mobility limitations (eg, grip strength, dexterity), loss of function, ulcerations, necrosis
Steal syndrome/ischemia is estimated to occur in approximately 5% of vascular access patients, mostly those with diabetes and peripheral vascular disease (PVD)
Clinical Clarification
Steal syndrome is estimated to occur in approximately 5% of vascular access patients, mostly those with diabetes and peripheral vascular disease.
“Claw Hand” Contracture From Steal Syndrome
Steal Syndrome/Ischemia
Steal symptoms may improve due to the development of collateral circulation
Procedures, such as the DRIL (distal revascularizationinterval ligation), can successfully treat steal and ischemia
Individuals who are at high risk for developing acute steal are: Patients with diabetic neuropathy Patients with PVD
Is Steal Syndrome Serious?
Steal/ischemia may lead to loss of function and amputation if not recognized and treated quickly Necrotic tissue cannot be “fixed”—it must be removed
Steal/ischemia places patients at risk for infection
Infection increases their risk for hospitalization
Hospitalization increases their risk for death!
Patient education
Check fistula daily for a thrill and bruit
Check for signs and symptoms of infection or other complications
Write instructions for infiltrations
Call Nephrologist
Thrill is weak
Signs of obstruction
Patient becomes feverish, dehydrated, or experiences low blood pressure
Thank you
Signs of obstruction
Patient becomes feverish, dehydrated, or experiences low blood pressure
Thank you
Acknowledgement to www.fistulafirst.org
Finished!
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