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EDEMATOUS STATES AND
RENAL DISEASE
Jan Bultas
Jitka Patočková
Ústav farmakologie, 3. LF UK, Praha
2009
Edema – the main reasons• Cardiac failure (failure as a „pump“)
- left ventricle (pulmonary edema)
- right ventricle (edema of lower extremities, ascites, hydrothorax)
• Failure of water excretion (from renal reasons, extrarenal – e.g. hormonal reasons etc.)
• Decrease of oncotic pressure - hypalbuminemia (proteinuria, protheonsynthesis failure – hepatopathy, …)
• Venous drainage failure (venous insufficiency, phlebotrombosis, etc.)
• Lymphatic drainage failure
DIURETICS• Heterogenous group of drugs which are able to increase
diuresis and excretion of electrolytes
• Main indications: • fluid retention (heart failure, pulmonary congestion, edemas,
ascites, hydrothorax) • hypertension
• Main clinical effects:• in heart failure they improve the quality of life, but we do not
have enough information about their influence on the life prognosis
• In hypertension they decrease the incidence of cerebral and myocardial attacks, they decrease mortality
DIURETICS – mechanism of action
• Transport proteins inhibition (inhibition of transport of ions in tubular system) (loop diuretics, thiazides, potassium sparing diuretics)
• Glomerular filtration increase (osmotic diuretics, methylxantines)
• Aldosterone inhibition (aldost. receptors blocators) or vasopressin inhibition (vasopres. receptors blocators – „aquaretics“, ev. alcohol)
DIURETICS – main groups
Henle´s loop diuretics
Distal tubule diuretics (thiazides)
Potassium-sparing diuretics
Na+, H2O
H2O
Na+
Cl-
H2O
Na+
Na+
K+Carbonic anhydrase inhibitors
osmoticdiuretics „aquaretics“
Aldost. receptors antagonists
Triamterene, amiloride
Na+
Cl-
loop diuretics
thiazides,indapamid
Mechanism of action of diureticsosmoticdiuretics,methylxantines
LOOP DIURETICS
Na+/K+/2Cl- co-transport inhibition in Henle´s loop
(- increase of ion (Na, K, Mg, H) and water excretion)
• Furosemide: huge diuretic effect, quick onset, short biological half life (1,5 hr), suitable for patients with significant renal failure, variable bioavailability . In patients with chronic heart failure, wide dose range 20mg -2g, not suitable as antihypertensive drug (short half life)
• torasemide: better profile, longer diuretic effect, stable bioavailability, enormous price
• bumetanide, ethacrynic acid – not used
LOOP DIURETICS
ADVERSE EFFECTS
• Potassium depletion, hypokalemia
• hyponatremia, hypomagnesaemia, hypovolemia - Glomerular filtration decrease in hypovolemia
• ototoxicity
• Increase of nephrotoxicity of a lot of nephrotoxic drugs (i.e. ATB)
DISTAL TUBULE DIURETICS - THIAZIDES Na+/Cl- co-transport inhibition in distal tubule
• Weaker diuretic effect, slow onset, long biological half life, stable bioavailability, narrow therapeutic window,
• No effect in patients with glomerul. filtration decrease (no effect in patients with renal insufficiency)
• Loop diuretics effect potentiation (convenient combination)
• Basic antihypertensives
• hydrochlorothiazide (6-12 hr, 6,25-25 mg), chlorthalidon (48-72 hr, 6,25-25 mg)
• indapamid: also vasodilatation (16-36 hr, 2,5 mg)
DISTAL TUBULE DIURETICS - THIAZIDES
ADVERSE EFFECTS
• Potassium depletion, hypokalemia
• hyponatremia, hypovolemia, hypotension
• metabolic effect in higher dosage: - glycid and lipid metabolism disturbances, hyperurikemia
• Clear tendency to use doses,• Be careful in diabetics
POTASSIUM - SPARING DIURETICSDirect antagonism of mineral corticoid receptors
(spironolactone)Na+ flux inhibition in collecting tubule
( triamterene, amiloride)• amiloride: weak diuretic effect, slow onset, long biological half
life (days), suitable for combinations (with loop diuretics, thiazides), as antihypertensive drugs and in the treatment of heart failure
• triamterene: less profitable, shorter effect
a combination of loop diuretics with potassium-sparing diuretics improve a life prognosis of the patients in comparison to the use of loop diuretics only
AE : hyperkalemia
Aldosterone receptors
Aldosterone rec. in distal tubule
mineral corticoid effect (Na+/K+ exchange)
Aldosterone rec. in myocardial tissue
Stimulation of fibro-proliferation
Aldosterone rec. in smooth muscles of blood vessels and endothelium
Stimulation of fibro-proliferation
Na+, H2O
H2O
Na+
Cl-
H2O
Na+
Na+
K+
Aldosterone receptors antagonists
Na+
Cl-
Aldosterone receptors antagonists
SPIRONOLACTONE aldosterone receptors antagonism in:• heart muscle: inhib. of fibroblast proliferation ( doses 25
mg/d)• kidneys: inhib. of Na/K pump in distal tubule – kalium
retention and natriuresis ( doses 50-300 mg/d)
• androgen-like effect (gynecomastia, menstruation disturbances)
• Active metabolite with longer half life (15 hr)• Cave! Risk of hyperkalemia
• Myocardial and renal effect - same as spironolactone• No androgen-like effect, better tolerated, expensive
EPLERENONE
Aldosterone receptors antagonists indication
• Chronic heart failure (decrease of mortality to 75%), „sub diuretic“ doses, main effect is prevention of hyperplasia of fibrous tissue in heart and vessels, combination with ACE-I, beta blockers, cardiac glycosides and diuretics
• hyperaldosteronismus (higher dosage)• cilium depletion and its prevention (medium
dosage)
Diuretics indication
Loop diuretics • Acute and chronic cardiac failure• Massive fluid retention, ev. retention in renal failure Thiazides• Antihypertensives of first choice• In combination with loop diuretics in poor diuretic
response Potassium-sparing diuretics• In combination with saluretics (loop d., thiazides)• Kalium depletion
RAA System
• Main role: keeping the body fluid volume and BP• AT1 receptors: vasoconstriction thirst stimulation
retention of fluids and Na in kidneys natriuretic pept. release stimulation aldosterone stimulation
• AT2 receptors: vasodilation• AT3 receptors : trombocytes activation
• RAA system is in balance with the kinin system and natriuretic peptide
RAA system activation - short time and long time effects
ACUTE ADAPTATION
increase of the volume of
fluid in circulation
perif. vasoconstriction
(to keep heart output and
perfusion pressure)
maintenance of
circulation
CHRONIC MALADAPTATION natrium and water retention myocytes
necrosis and apoptosis fibrous tissue proliferation fibrinolysis inhib. PAI-1 sympathic syst. activation
break down of circulation
Renin-Angiotensin-Aldosterone System
angiotensinogen
angiotensin I
angiotensin II
aldosteron
ANP,BNP thirst Na+ resorp. vasoconstriction
RENIN
rec. AT1
ACE
Fibroblasts proliferation
Na+ retention
Renin-Angiotensin-Aldosterone System
angiotensinogen
angiotensin I
angiotensin II
aldosterone
ANP,BNP thirst Na+ resorp. vasoconstriction
RENIN
rec. AT1
ACE
Fibroblasts proliferation
Na+ retention
Beta- blockers, Renin inhibitores
ACEInhib.
AT inhibitores
aldosteron. rec.antagonists
ACE-INHIBITORS – MECHANISM OF ACTION:1) Inhibition of A I to A II conversion
2) Inhibition (slow down) of bradykinin degradation
Pharmacodynamic:- decrease of peripheral vessels resistance- specific dilation of vas efferens (intraglomerul. pressure
decrease, GF decrease)- decrease of ALDOSTERONE and ADH release + thirst suppress (decrease of Na and H20 retention)
- decrease of NORADRENALIN release- Stimulation of fibrinolysis - Antimitogenic activity + inhibition of apoptosis
Indication of ACE-I
• arterial hypertension
• Chronic heart failure
• Prophylaxis of nephropathy progression (specially Diabetic
nephropathy )
• For better prognosis and decrease of morbidity in patients
with cardial ischemia and after cerebral attack
Adverse effects and contraindications of ACE-IAE: • cough (cca in 5% of patients should discontinue a drug)• angioedema (less than 1%)• hypotension, first dose phenomenon (kaptopril, hypovolemia)• Worsening of renal function (decrease of intraglom.
pressure)• hyperkalemia• KI: • gravidity!!!• bilat. stenosis of ren. Art., signif. AO stenosis and obstructive
cadiomyopathy
Widely used ACEI
Enalapril 2x 5-20 mg
Fosinopril 1x 10-20 mg
Imidapril 1x 5-10 mg
Lisinopril 1x 20-80 mg
Moexipril 1x 7,5-15 mg
Perindopril 1x 4-8 mg
Quinapril 1-2x 5-20 mg
Ramipril 1x 2,5-10 mg
Spirapril 1x 6 mg
Trandolapril 1x 2-4 mg
Influence on mortality in patients after myocardial infarction – different ACEI
(ONTARIO)
ramiprilperindopril
lisinoprilenalaprilquinaprilfosinoprilkaptopril
100%
90%
80%
0 6 12 měs.Pilote L et al, Ann Intern Med, 2004
Renin-Angiotensin-Aldosterone System
angiotensinogen
angiotensin I
angiotensin II
aldosterone
ANP,BNP thirst Na+ resorp. vasoconstriction
RENIN
rec. AT1
ACE
Fibroblasts proliferation
Na+ retention
Differences in Effect of AT1 blockers and ACE-I
ACE ACE natriuréza
vazodilatace stimul. NOS
AII
BKACE-I
ACE-I
Differences in Effect of AT1 blockers and ACE-I
ANP,BNP thirst resorp. Na+ vasoconstriction retence Na proliferation
rec. AT1
ACE
antiproliferativní vazodilatace stimul. NOS
rec. AT2
AII
ARB rec. AT3
aktivace trombocytů
Effects of AT1 receptor antagonists
• vasodilation, decrease of peripheral resistency (weaker effect than in ACE-I, there is no effect on bradykinin)• decrease of fluid retention• inhibition of LV remodelation ( apoptosis, necrosis) • suppression of sympaticotonia
• specif. dilation of vas efferens (decrase of intraglom. pressure)
• there is no evidence of the effect on correction of edothelial dysfunction
Advantages and disadvantages of AT1 rec. antagonists
advantages
• better tolerability (less
cough and angioedema)
disadvantages• weaker effect on vasodilation and antihypertensive effect (no effect on bradykinin)
Indication of AT1 receptor antagonists
• Arterial hypertension
• Profylaxis of nephropathy progression (spec.
diabetic)
• Better prognosis and decrease of mortality in patients with cardiac
ischemia and in patients after stroke
• Chronic cardiac failure
AE and contraindications of sartansAE: • hypotension, (namely in hypovolemia)• Worsening of renal function (decerase of glom.
pressure)• hyperkalemia • Cough and angioedema (rarely)CI: • gravidity!!!• bilat. Stenosis of renal art., significant AO stenosis,
obstructive cardiomyopathy
Therapy of venous insufficiency
• Pathogenesis - increase of venous pressure in distal part of venous system (LE namely)
• Participation of inflammatory agents
• Therapy is focused on profylaxis and regime changes
• Pharmacotherapy has limited importance, there is some effect on decrease of pain, cramps, heaviness, and in some cases acceleration of varicose ulcers
Pharmacotherapy of venous insufficiency
• Natural substances (flavonoides) – diosmine, hesperidine, aescin etc.
• semisynthetic – troxerutin
• synthetic – calcii dobesilat etc.
• The combination diosmine + hesperidine seems to be the most evidential (EBM)
Renal excretion of drugs and their metabolites
a) Glomerular filtration
b) Tubular secretion
c) Passive Tubular diffusion
Glomerular filtration
• Filtration of molecules (drugs) up to molecular weight
20 000
• Hydrophilic drugs - mainly free filtration
• Lipophilic drugs - binded to albumin, just free fraction
is filtrated (cca 2%)
• cca 20% of renal perfusion – i.e.. Cca 20% of drug
excretion
Tubular secretion and passive diffusion• 80% of renal perfusion - plasma / drug – in
peritubular capillary syst.• In prox. Tubulus the transport systems excrete
xenobiotics to urine• Tubular secretion is the most effective system in drug
clearance • Lipophilic molecules move freely through the tubular
wall and back to plasma (diffusion) • Hydrophilic molecules (ionized) – no diffusion• pH changes influence significantly drug ionization –
drug excretion
Drug dosage in renal failure
• Drug dosage (in acute and chronic treatment)– Loading (first) dose – without reduction – Maintenance (repeated) dose - reduced
• Dosage reduction information– SPC, AISLP, Cocroft Gault formula, etc.
• TDM in drugs with narrow therapeutic window and renal excretion only– Digoxin, amino glycosides, vancomycin
Drug dosage in renal failure - examplesAntihypertensive drugs:
– No reduction: calcium channel blockers, AT1 antagonists, Lipophilic beta blockers (metoprolol), furosemide
– Mild reduction: ACE-I (to half of normal dosage)– Reduction according to GF: hydrophilic BB (atenolol, bisoprolol)
• statines: no reduction• insulin: cave: biol. half time prolongation, higher effect! • Opioid analgesics: biol. Half time prolongation (tramadol)• NSAIDs: different / according to molecular structure• corticoids: no reduction • digoxin: reduction according to GF, in renal failure up to 0,125
mg 2x weekly– Always consider the indication and do TDM!
Dosage of ATB in renal failure• Penicillin ATB + betalactamase inhibitors (Augmentin, Unasyn)
– Prolongation of dosage interval to double
• cephalosporines, chinolones
– Prolongation of dosage interval to double
• macrolides – no reduction
• Co-trimoxazol - Prolongation of dosage interval to double • aminoglykosides
– Significant reduction (see guidelines), always TDM
• vancomycin– Significant reduction (see guidelines)– Dosage interval up to 7 days– Always TDM
Diuretics in Treatment of renal failure
• Decrease of GF is not an indication of diuretic treatment• thiazides – thiazides only - no effect in GF < 0,5 ml/s
- in combination with loop diuretics – in any GF• Loop diuretics – ekvipotent dose increases exp. with the GF reduction
• Diuretic treatment indication:– Fluid retention / edema – Heart failure with fluid retention– hyperkalemia– Antihypertensive therapy
Severe AE of drugs in renal failure
hyperkalemiaACE-I, AT1 rec. antagonists, spironolaktone, amiloride,
KCl
decrease of GFACE-I, AT1 rec. antagonists, NSAID
Cave: in renal perfusion disturbances take care about blood pressure (be careful in hypotension)
Drug nephrotoxicity in renal failure• Higher risk in
• Renal hypoperfusion• Risk combinations (spec. with NSAID)• Elderly people- Possibly irreversible damage!
• Potentially nephrotoxic drug– Consider indication!– discontinue other potentially dangerous drugs– After good hydration– Renal function control afterwards
Drug nephrotoxicity- examples
– Rtg contrast substances
– aminoglykosides
– Some other ATB (cotrimoxazol, cephalosporines, vancomycin)
– NSAIDs (significant ren. Vasoconstriction in prostanoid
synthesis inhibition)– ACE-I and AT1 antagonists – GF decrease, mild
worsening of renal function, but nevertheless nephroprotective effect
Drugs contraindicated in renal failure
• Oral antidiabetics
– metformine – absolutely contraindicated
– Most of sulphonylurea derivates
• nitrofurantoin
• Aldosterone receptor inhibitors (spironolaktone, eplerenone)
Mistakes in pharmacotherapy in renal failure
• Renal failure is not recognized
• Potentially risk combination is given without any control
• AE of NSAID are not enough considered
• Dehydration is not enough considered
• Treatment with loop diuretics where is no indication for
them
ImmunosupressionThe Aim:• To diminish selectively immune activity, ie. selective
depression of T and B lymphocytes activation • To keep nonspecific immunity, ie. To keep the function of
Polymorphonuclears and monocytes/macrophages
Indications:• To reach transplant acceptation and to keep resistance
against infection and tumor growing• To decrease activity of diseases based on
immunoalteration
Immunosupression
Mainly combination of
• Substances with complex antiinflammatory effect -
cortiocoids
• Substances with antimetabolit effect – mycophenolat,
azathioprim
• Substances inhibiting transfer of activating signal in T
lymphocytes – cyclosporin A, tacrolimus, rapamycin
• Lymphocyte antibodies (antilymphocytes)
Glucocorticoids
• Anti-inflammatory effect: depression of function of T-lymphocytes and mono/macrophages, depression of (inflammatory) cytokines production, decrease of vascular permeability, depression of fibroprolipheration,…
• Metabolic effect:
- Decrease of glucose utilization - Increase of gluconeogenesis - hyperglycemia
- Increase of protein degradation (catabolism)- Redistribution of fat • Bio-feedback: decrease of glucocorticoids production
Cyclosporin A• Inhibition of signal transfer from activating
receptor on T-lymphocyte to nucleus – block of cytokines synthesis and secondarily also T-lymphocytes activation
• Cyclic peptide, very potent immunosuppressant• Significant nephrotoxicity, vasoconstriction
Tacrolimus, rapamycin
• Similar mechanism of action in T- lymphocytes • Very potent immunosupression• Better tolerability, rapamycin is not nephrotoxic