Download Vascular access complications during dialysis

Vascular access complications
during dialysis - II
Dr.
Hemodialysis vascular access
The number of patients with end-stage
renal disease (ESRD) are increasing
The creation and maintenance of
functioning vascular access, along with the
associated complications, constitute the
most common cause of morbidity,
hospitalization, and cost in patients with
ESRD
Vascular Access via Percutaneous
Catheters
useful method of
gaining immediate
access to the
circulation.
associated with
higher risks.
the use-life of this
type of access is
shorter than that of
AVFs.
Noncuffed catheters
Short term: <3 weeks
Vascular Access via Percutaneous
Catheters: cuffed catheters
Cuffed catheters
Patients who will require
long-term access should
have a tunneled catheter
placed.
allow so-called no-needle
dialysis with high flow
rates
eliminate the problem of
vascular steal
placed in a subcutaneous
tunnel under fluoroscopic
guidance
Vascular Access via Percutaneous
Catheters: cuffed catheters
The Dacron cuff allows tissue
ingrowth that helps reduce the risk
of infection when compared with
noncuffed catheters.
Hemodialysis access: Complications
Complications can be divided into those
that occur secondary to catheter
placement and those that occur later
The early complications of subclavian or
internal jugular placement include
– pneumothorax, arterial injury, thoracic duct
injury, air embolus, inability to pass the
catheter, bleeding, nerve injury, and great
vessel injury
Hemodialysis access: Complications
(contd)
A chest radiograph must be taken after catheter
placement to rule out pneumothorax and injury
to the great vessels and to check for position of
the catheter
The incidence of pneumothorax is 1% to 4%,the
incidence of injury to the great vessels is less
than 1%
Thrombotic complications occur in 4% to 10% of
patients
Hemodialysis access: Complications
Infection may occur soon after placement
(3 to 5 days) or late in the life of the
catheter and may be at the exit site or the
cause of catheter-related sepsis
Rate of infection between 0.5 and 3.9
episodes per 1000 catheter-days
Catheter thrombosis increases the
incidence of catheter sepsis
Catheter complications
The causes of haemodialysis catheter
dysfunction are related to the
– Duration of implantation and
– Use
Immediate/early dysfunction usually
results from
– Mechanical problems, such as
Malpositioning of the catheter tip (sucking the wall
of the vein), kinking of the catheter or
Strictures caused by ligatures or aponevrosis
Best Practice & Research Clinical Anaesthesiology 2004;18:159-74
Catheter complications (contd)
Late dysfunction (> 2 weeks) is more often
caused by
– Thrombotic problems:
Partial or total obstructive thrombosis of the
catheter lumen,
Thrombosis or stenosis of the cannulated vein,
External fibrin sheath formation on the catheter
distal end or
Internal coating of the catheter (endoluminal fibrin
sleeve)
Best Practice & Research Clinical Anaesthesiology 2004;18:159-74
Catheter complications (contd)
Endoluminal catheter thrombosis is the most
common thrombotic complication
– Revealed by intermittent or permanent catheter
dysfunction
– Such catheters may be re-opened by mechanical
methods (brush) or chemical methods (fibrinolytic)
External thrombosis, caused by a fibrin sheath
covering the tip of the catheter,
– Requires either fibrinolysis, catheter stripping through
a percutaneous femoral route, or removal and
replacement
Best Practice & Research Clinical Anaesthesiology 2004;18:159-74
Catheter complications (contd)
Thrombosis of the cannulated vein is a
severe complication and a
– Potential source of pulmonary embolism
– The incidence may vary from 20 to 70%
depending on the site and diagnostic modality
used
– Thrombosis of the right atrium is the most
serious and potentially lethal complication
Best Practice & Research Clinical Anaesthesiology 2004;18:159-74
Catheter complications (contd)
Symptoms of thrombosis
– Rare and often deceptive, marked by a catheter
dysfunction, by the onset of ipsilateral limb oedema or
by unexplained fever
– Several factors contribute to the thrombogenicity,
including
The catheter itself (material and composition of the catheter,
softness, aspect and surface treatment), the mode of
insertion, the site of insertion (diameter, local
haemodynamics), the duration of cannulation, the
coagulation and inflammatory state of the patient
(hyperfibrinaemia, inflammatory syndrome,
hyperthrombocytaemia, previous venous thrombosis) and
contamination of the catheter
Best Practice & Research Clinical Anaesthesiology 2004;18:159-74
Catheter complications (contd)
Infections represent a major threat for haemodialysis
catheters in the ICU
Nontunnelled polyurethane catheters, used for shortterm therapy, entail a risk of bacteraemia estimated at
8.5 episodes per 100 patient-months compared to five
episodes per 100 patients-months for cuffed tunnelled
catheters
The incidence of bacteraemia varies greatly according to
units and clinical practices, being higher in teaching
hospitals
Non-tunnelled internal jugular access bears a higher risk
of infection, particularly in patients with a tracheotomy
Best Practice & Research Clinical Anaesthesiology 2004;18:159-74
Catheter complications (contd)
Early infection may be related to problems
associated with catheter placement or to skin
and catheter track infection
Placement of a percutaneous catheter disrupts
the continuous protective layer of the skin
– The skin acts as a bacterial reservoir and contributes
to the subcutaneous penetration of germs along the
catheter pathway, explaining the need to disinfect the
skin carefully prior to any catheter insertion, in order
to prevent the onset of cutaneous lesions, and to
ensure particular care in patients with catheters
Best Practice & Research Clinical Anaesthesiology 2004;18:159-74
Catheter complications (contd)
Late infections are most often associated with
endoluminal catheter contamination
It must be alleviated through suitable nursing
care and handling
Two types of infection are observed:
– Local infection (skin exit, tunnel infection) and
– Systemic infection (bacteraemia, septicaemia,
infected thrombosis)
Skin exit and bacteraemia are the most frequent
forms of infection that may be treated with local
and systemic antibiotic therapy while keeping
the catheter in situ
Best Practice & Research Clinical Anaesthesiology 2004;18:159-74
Catheter complications (contd)
Catheter track infection (tunnellitis), septicaemia,
fungaemia and infected venous thrombosis are
the most severe form of infections requiring both
catheter withdrawal and systemic antibiotic
therapy
Endoluminal contamination from hubs may form
a microbial biofilm. In this case, bacteria entering
the lumen adhere to the catheter surface, grow,
produce glycocalyx (slime) and become
resistant to antibiotics
Best Practice & Research Clinical Anaesthesiology 2004;18:159-74
Catheter complications (contd)
Occasionally, bacteria may be released from this biofilm
(e.g. higher stress conditions due to the blood pump
speed), being the source of bacteraemia and fever
episodes
In the event of an unexplained septic condition, it is
advisable to consider the catheter as a source of
infection
Several authors have proposed catheter replacement
over a guidewire through the same subcutaneous track
– This microbiologically unsafe approach appears undesirable
– Another approach is to change the catheter systematically every
3–4 days and insert it in a different venous site
Best Practice & Research Clinical Anaesthesiology 2004;18:159-74
Catheter complications (contd)
In any case it is essential to culture the
withdrawn catheter
The insertion of soft tunnellized catheters (with
or without anchoring system) for long-term use
appears more suitable to prevent catheter
hazards
Strict aseptic rules (gloves, mask, drapes,
antiseptic) should be followed at all times and
particularly at the time of line connection to
prevent contamination of catheter hubs
Best Practice & Research Clinical Anaesthesiology 2004;18:159-74
Catheter complications (contd)
Stenosis of the host vein is a common
long-term risk of catheters
– It is more common with semirigid catheters
than with soft catheters and more frequently
observed with the subclavian route than with
the jugular one
– This troublesome complication may
compromise the future creation of
arteriovenous fistula in ESRD patients
Best Practice & Research Clinical Anaesthesiology 2004;18:159-74
Catheter complications
In conclusion, catheter-related
complications may be significantly reduced
by
– improving the quality of catheter care and
– implementing a continuous quality
improvement programme with the nursing
staff
Best Practice & Research Clinical Anaesthesiology 2004;18:159-74
Vascular Access via Arteriovenous Fistulas
The ideal vascular access
– permits a flow rate that is adequate for the
dialysis prescription (³ 300 ml/min),
– can be used for extended periods,
– and has a low complication rate.
The native AVF remains the gold standard
Arteriovenous fistulas
The standard by which all other fistulas are measured, is
the Brescia-Cimino fistula. (2 year patency: 55% to 89%)
•radial branch-cephalic direct access
(snuffbox fistula),
•autogenous ulnar-cephalic forearm
transposition,
•autogenous brachial-cephalic upper
arm direct
•access (antecubital vein to the
brachial artery),
•autogenous brachial-basilic upper
arm transposition (basilic vein
transposition).
These options should be exhausted before
nonautogenous material is used for dialysis access.
Noninvasive Criteria for Selection of Upper-Extremity
Arteries and Veins for Dialysis Access Procedures
Venous examination
Venous luminal diameter  2.5 mm for autogenous AVFs,  4.0 mm for
bridge AV grafts
Absence of segmental stenoses or occluded segments
Continuity with the deep venous system in the upper arm
Absence of ipsilateral central vein stenosis or occlusion
Arterial examination
Arterial luminal diameter  2.0 mm
Absence of pressure differential  20 mm Hg between arms
Patent palmar arch
radiocephalic fistula
(anatomic snuff-box)
radiocephalic fistula
(Brescia-Cimino)
Vascular access via AVFs:
brachiocephalic fistula
brachiobasilic fistula
Arteriovenous fistulas: Complications
Failure to mature
Stenosis at the proximal venous limb (48%).
Thrombosis (9%)
Aneurysms (7%)
Heart failure
The arterial steal syndrome and its ensuing ischemia
occur in about 1.6%: pain, weakness, paresthesia,
muscle atrophy, and, if left untreated, gangrene
Venous hypertension distal to the fistula : distal tissue
swelling, hyperpigmentation, skin induration, and
eventual skin ulceration.
Complications of mature AVFs
Venous thrombosis
– Due to needle trauma or prolonged
compression after dialysis-needle withdrawal
Venous aneurysm
– Can ease cannulation, and
– Surgical correction is only considered in the
case of threatened rupture, when thrombus
impairs blood flow or makes the needle
insertion difficult
J Vasc Nurs 2010;28:78-83
Complications of mature AVFs
(contd)
Edema due to central venous obstruction
of the limb will require angioplasty or
stenting of a lesion to relieve symptoms
When distal hand ischemia is present due
to the fistula robbing blood flow from the
hand, the radial artery is ligated just distal
to the fistula to relieve ischemic symptoms
– The access remains preserved for the
hemodialysis treatments
J Vasc Nurs 2010;28:78-83
Complications of mature AVFs
(contd)
Early thrombosis, or failure of the vein to dilate
and mature, will require surgical revision of the
primary fistula
Late complications of low-flow, higher venous
pressures, and increase in the dialysis
recirculation time can indicate a failing access
Late complications of the deteriorating AVF
require prompt attention and patient should not
delay seeking medical care
J Vasc Nurs 2010;28:78-83
Complications of mature AVFs
Imaging of the vessels can greatly assist to
pinpoint the specific problem area of a failing
access
Surgical revision, endarterectomy or angioplasty
can correct a fistula beforetotal occlusion occurs
Attempts to salvage a failing AVF are preferable
over placement of a new access in a fresh site
A limited number of sites are available for
access placement and serious complications
may render a site unusable forever
J Vasc Nurs 2010;28:78-83
Prosthetic Grafts for vascular access
Upper arm grafts have a high flow rate and a low
incidence of thrombosis.
higher incidence of ischemia in the hand
higher rate of stenosis, sec to endothelial hyperplasia.
Complications of prosthetic grafts
Prosthetic grafts have complications similar to
fistula, such as
– loss of patency due to poor blood flow,
– infection or vascular disease, and
– pseudoaneurysm due to repeated cannulation in the
same area
A decrease in blood pressure can reduce flow
through the graft, causing clot formation and
vein collapse
Infection in other parts of the patient’s body can
result in infection and damage to the prosthetic
graft and at the operative site
J Vasc Nurs 2010;28:78-83
Complications of prosthetic grafts
(contd)
The AV grafts are more prone to frequent
stenosis and thrombosis, requiring surgical
intervention and thus are more costly and
labor intensive than a native AVF
Patients with an AVF have fewer
complications and less frequent
hospitalizations and incur lower costs in
comparison with patients with prosthetic
grafts or catheters for hemodialysis
J Vasc Nurs 2010;28:78-83
Options for treating steal
DRIL procedure
distal revascularizationinterval ligation
excision of a portion of the vein
plication w/ mattress or
continuous sutures
crossed PTFE band
interposition of a 4 mm PTFE
Treatment of venous access complications.
Venous angioplasty
Graft thrombolysis
Contraindications to Thrombolytic Therapy
Absolute
Recent major bleeding
Recent stroke
Recent major surgery or trauma
Irreversible ischemia of end organ
Intracranial pathology
Recent ophthalmologic procedure
Relative
History of gastrointestinal bleeding or
active peptic ulcer disease
Underlying coagulation abnormalities
Uncontrolled hypertension
Pregnancy
Hemorrhagic retinopathy
Hemodialysis
access
Quality of life and overall outcome could be
improved significantly for hemodialysis
patients if two primary goals were achieved:
– Increased placement of native AVFs: a minimum
of 50% of new dialysis patients should have
primary AVFs.
– Detection of dysfunctional access before
thrombosis of the access route occurs.
National Kidney Foundation Dialysis Outcome and Quality Initiative (NKF-DOQI)
Conclusions
Vascular access is associated with
complications like stenosis, thrombosis,
infections etc
Early detection is required for better
management of such complications
Conclusions
Various interventions like
surgical/pharmacological are available for
the management of such complications
Proper care is beneficial in prevention of
such complications and thereby reducing
morbidity and cost
VASCULAR ACCESS IS THE PATIENTS
LIFE LINE , PLEASE LOOK AFTER IT.
Many Thanks