Transcript Dialysate Na

What is sodium modeling in
hemodialysis patients?
Causes of Intradialytic hypotension(IDH)
Excessive fluid removal
Ultrafiltration rate > 0.35 ml/min/kg
Decrease in plasma vol. > 20%
Reduced
plasma
refilling rate
Reduced ECV
Hemorrhage
Impaired
Vasoconstriction
Intradialytic
Hypotension
Myocardial Infarction
Structural heart dis.
Pericardial tamponade
Autonomic neuropathy (e.g. DM, Uremia)
Antihypertensive medications
Sympathetic failure (적절한 plasma NE↑가 無)
RAS and arginine-vasopressin syst. sensitivity↓
Food ingestion(splanchnic vasodilation)
Tissue ischemia(adenosine mediated)
Bacterial sepsis
Intradialytic venous pooling
Core body temp.↑
Anemia.
Dialysis-related factors
Heart problems
Arrythmias
Patient-related factors
Hemolysis
Dialyzer Rxn
Air embolism
Acetate dalysate (adenosine-mediated)
Low dialysate Na &/or ionized Ca conc.
Complemant activation (C3a and C5a-mediated)
Cytokine generation(IL-1 and NO-mediated)
Water movement during standard hemodialysis
Intracellular fluid
Extracellular fluid
Dialyzer
step3
Water movement
step1
280
Osmolality
320 mosm/kg
Osmolality
320 mosm/kg
Falling to
290mosm/kg
as diffusion occurs
Compensatory refilling
step2
Loss of urea
and water
Fluid removal
Plasma refilling
Fluid removal
Fluid removal
Na
Low Na
130-135 meq/l
Na
Increased risk of
hypotension
Historically the dialysate Na was
maintained at hyponatremic level, 130-135:
To prevent:
 Intradialytic hypertension
 Thirsty
 Interdialytic weight gain
Disadvantages of dialysates with low
sodium concentration:
 Increased risk of hypotension
 Increased risk of intradialytic cramps
 Increased risk of dialysis disequilibrium
syndrome
urea removed
by dialyzer
urea sequestration
in tissue
fluid
Effluent
Dialysate
Increased intracellular
osmolarity
Inffluent
Dialysate
fluid
Na
High dialysate sodium:
Advantages:
Disadvantages:
 Decreased risk of
hypotension
 Increased rate of
hypertension
 Decreased risk of
intradialytic cramps
 Interdialytic weight gain
 Decreased risk of dialysis
disequilibrium syndrome
 Polydipsia
Fluid removal
Plasma refilling
Na
Low Na >145 meq/l
Na
Different patterns of sodium modeling
145-155 meq/lit
Na concentration
135-140 meq/lit
Hours after dialysis initiation
Dialysate Na should be regulated based on
serum Na:
hyponatremia:
 If Na > 130: Dialysate Na: 140-(140-predialysis Na)
 If Na<130: Dialysate Na: Predialysis Na + 15-20
Hypernatremia:
 Dialysate Na: Predialysis Na-2 mmol
Goals of UF Profiling
Provide adequate ultrafiltration (UF)
Minimize symptoms related to hypovolemia
Enhance plasma refill
Allow the patient to reach estimated dry weight (EDW)
Plasma refill: Refilling
of the blood
compartment, or
vascular space from
the surrounding tissue
spaces
Hypovolemia: Decreased blood volume leads
to decreased cardiac output which can cause
hypotension
Fluid Spaces in the Body
Average weight Male
70 kg or 154
lbs.
VASCULAR SPACE
4 LITERS WATER, 5%
INTERSTITIAL SPACE
11 LITERS WATER, 15%
Extracellular
60% of Total
Body Weight
is
42 liters
of
water
BONE, MUSCLE, FAT
INTRACELLULAR
SPACE
27 LITERS
WATER
40%
20
Two Basic Reasons That Patients End up With
Dialysis Symptoms During Treatment
The loss of circulating volume in the vascular space
The loss of osmolarity as the urea is removed during
dialysis
Only fluid in the vascular space is available
during dialysis for ultrafiltration. This amounts
to less than 4L in the average patient
21
Symptom Etiology
With Constant Ultrafiltration
Ultrafiltration
(UF) removes
water volume
from the blood
into the
dialysate,
causing
hypovolemia
Symptoms
of Volume
loss:
•Hypotension
•Cramping
•Dizziness
•Nausea
•Vomiting
•Shock
22
Profiling Ultrafiltration:
Allows the patient to reach their estimated dry weight (EDW)
Helps prevent symptoms
Allows refilling of vascular fluid volume from the interstitial space
(plasma refill)
Allows higher volume fluid removal at times when fluid is more readily
available
Prevents hypotension
23
How to Do UF Profiling
Identify patients with dialysis related symptoms
Analyze patient’s treatment records
Decide if the patient will benefit from a profile
Choose a profile that matches your analysis
24
Things to Consider for Ultrafiltration
Profiling
Does the patient have difficulty with fluid
removal?
Have the MD answer these questions:
◦ What UF rates can the patient tolerate?
◦ Will the patient require periods of minimum UF?
◦ How will patient co-morbidities affect fluid removal?
◦ What type of profile would be best suited for the
patient?
25
Individualize the Prescription
Based Upon the Patient’s
Treatment History
Determine when the patient typically
demonstrates symptoms. Beginning – mid –
end of treatment?
Does the patient need minimum UF to
complete the treatment?
Evaluate the pre treatment systolic blood
pressure (SBP)
Evaluate the patient’s weight gains between
treatments
26
Choosing the Right UF Profiles
A profile that begins with the highest UF that can be
tolerated by the patient which then decreases to a
minimum will work for patients:
Linear
Progressive
With large weight gains between treatments
Who become hypotensive late in treatment
Who cramp late or at the end of treatment
Step
Step
With large weight gains between treatments and
present with an elevated BP
27
Choosing the Right UF Profiles
Consider a profile with varying steps for
patients who:
Need a gradual increase in UF at the beginning of the
treatment to support low BP or cardiac output
Need short intervals of minimum UF to allow for
plasma refill
Have difficulty shifting fluid into the vascular space
(elderly, diabetic or unstable)
Cramp or are hypotensive randomly during treatment
28
Case Studies
How to select a UF profile
for a patient
29
A patient weight gains
typically of 3-4 kg and
experiences moderate to
severe leg cramps during
the last 30 minutes of
treatment
30
Patient tolerates fluid
removal (higher UF)
at the beginning of
treatment
220
200
180
Symptoms are
relieved at the
end of treatment
with a lower UF
160
140
120
100
80
UF Profile
60
40
3
0
60
90
120
150 180
210 240
Time in Minutes
31
220
Systolic BP
Fluid overloaded
200
patients benefit from
180
aggressive UF at
1.8
Kg/h
160
the beginning of the
treatment 140
1.0
0.7
120
0.3
100
Step profiles allow
for
80
dramatic decreases
in UF.
60
Lower UF at the 40
middle
and90
30 60
end of treatment will reduce
the patient’s symptoms
UF Profile
120
150 180
210 240
Time in Minutes
32
Second patient arrives with a
systolic blood pressure of 85 and
a weight gain of 3 Kg. If her SBP
falls below 75 she becomes
symptomatic
33
Less UF
should be used
220
at the beginning of
200while the SBP
treatment
is low. Increase the UF
180
during periods when the
SBP
160is higher
Decrease the UF
toward the end of
treatment as the
patient
approaches her
dry weight to
prevent symptoms
140
120
100
80
60
40
30
60 90
120
150
180
210
240
Time in Minutes
34
220
Using a Step Profile, you can
create multiple minimum UF
periods which will allow
plasma refill to occur.
Decrease the UF toward the
end of treatment as the patient
approaches her dry weight to
prevent symptoms
200
180
160
140
120
100
80
60
40
30
60 90
12
0
150
180
210
240
Time in Minutes
35
A woman patient is hypertensive
and diabetic. She has large fluid
gains of 4-6 Kg between
treatments and has symptoms of
hypotension about 45 minutes into
the treatment as well as mid and
late treatment
36
Assessment and Plan
Assessment:
◦ Large fluid gains
◦ Severe hypotensive episodes
◦ Poor plasma refill
Plan
◦ Support plasma refill, especially during the first part
of the treatment
◦ Prevent hypovolemia
◦ Consider conductivity profiling in addition to UF
profiling
37
220
200
Utilize a
Conductivity
profile to support
solute removal
180
160
140
120
100
80
60
40 30
60
90
120 150
Arrows
indicate
plasma refill
times240
180 210
Time in Minutes
38
220
UF and Conductivity Profiling
can be used simultaneously
with similar step curves
200
180
160
140
120
100
80
60
40 30
60
90
120 150 180 210 240
Time in Minutes
39
220
200
Systolic BP
180
160
140
120
UF and Conductivity Profiling
100
can be used simultaneously
with 80
similar progressive curves
60
40 30
60
90
120 150 180 210 240
Time in Minutes
40
Summary of UF Profiling
Allows unlimited variation of ultrafiltration rates so
that fluid can be removed from the vascular space
while preventing symptoms
Allows periods of automatic plasma refilling to
allow adequate fluid removal
Decreases the patient’s symptoms
May be used simultaneously with conductivity
profiling
41
References
Heinrich, W.L. & Victor, R.G., “Autonomic Neuropathy and Hemodynamic Stability in EndStage Renal Disease Patients”, Principles and Practice in Dialysis, Williams and Wilkins,
Baltimore, 1994.
Wilson, S., Alvarez, D., A Primer on Ultrafiltration Profiling and Sodium Modeling for
Dialysis Patients, Contemporary Dialysis and Nephrology, April 2000, pp 34-36.
Bonomini, V., Coli, L., Scolari, M.P., Profiling Dialysis: A New Approach to Dialysis
Intolerance, Nephron 1997; 75:1-6
Leunissen, K.M.L., Kooman, J.P., van der Sande, F.M., van Kuijk, W.H.M., Hypotension
and Ultrafiltration Physiology in Dialysis, Blood Purif 2000; 18:251-254
Oliver, M.J., Edwards, L.J., Churchill, Impact of Sodium and Ultrafiltration Profiling on
Hemodialysis Related Symptoms, J Am Soc Nephrol 12: 151-156 2000
Jensen, B.M., Dobbe, S. A., Squillace, D.P., McCarthy, J.T., (April 1994) Clinical Benefits
of High and Variable Sodium Concentration Dialysate in Hemodialysis Patients, ANNA
Journal, Vol. 21, No. 2.
42
References
Gambro Basics 1 Gambro Education 1994
Petitclerc, T. and Jacobs, C. Dialysis sodium concentration: what is optimal and can it be
individualized? , Nephrol Dial Transplant Editorial Comments1995, 596-599.
Coli, L., Ursino, M., Dalmastri, V., Volpe, F., LaManna, G., Avanzolini, G., Stefoni, S.,
Bonomini, V., A simple mathematical model applied to selection of the sodium profile
during profiled haemdialysis, Nephrol Dial Transplant (1998) 13:404-416
Donauer,J., Kolblin, D., Bek, M., Krause, A., Bohler, J., Ultrafiltration Profiling and
Measurement of Reletive Blood Volume as Strategies to Reduce Hemodialysis-Related
Side Effects, AJKD, Vol 36, No 1 (July), 2000:pp115-123
Stiller, S., Bonnie-Schorn, E., Grassmann, A., Uhlenbusch-Korwer, Mann, A Critical
Review of Sodium Profiling for Hemodialysis, Seminars in Dialysis, Vol 14, No 5
(September-October) 2001 pp. 337-347
Locatelli, F., DiFilippo, S., Manzoni, C., Corti, M., Andrulli, S., Pontoriero, G., Monitoring
sodium removal and delivered dialysis by conductivity, The International Journal of
Artificial Organs/Vol. 18/no. 11, 1995/pp716-721
43