Diuretic Therapy
Overview Contrasting uses of diuretics in OR versus Critical Care Lecture sections: - Anatomy & Physiology - Renal Effects of Anesthesia Drugs - Diuretic Drugs by Class - Intra-operative Uses - Adjuvant Therapy
Renal Anatomy Size Regions Functional Unit Blood Supply Tubular Systems Hemodynamics Hydraulics
Structure
Renal Physiology Filtration Reabsorption Secretion Minor functions
Nephron
Tubular segment characteristics
Juxta-glomerular complex
Nephron
Counter-Current Mechanism What is it? How does it work? Why is this so important?
Counter-current mechanism in kidney
Tubular fluid osmolarity
Hormonal Regulation Anti-diuretic Hormone (ADH) Aldosterone Renin-angiotensin Atrial Natriuretic Peptide (ANP) Prostaglandins Epinephrine/Nor-epinephrine Dopamine
Anti-diuretic hormone feedback
Aldosterone & renin-angiotensin
Responses to Anesthetic Agents Inhaled agents Intravenous agents Regional anesthesia
Diuretic Classification Osmotic agents Carbonic Anhydrase Inhibitors Loop Diuretics Aldosterone Antagonists Potassium-sparing Agents Thiazide Diuretics Xanthines
Diuretic sites of action
Intra-operative Uses ICP reduction IOP reduction Renal failure prophylaxis Oliguria assessment & treatment General strategies
Rhabdomyolysis Peaked T-waves Myoglobinuria
Causes Muscle trauma/ischemia/exertion Substance abuse Medication Toxins Electrical injury Hyperthermia Infections Transfusions Electrolyte disorders
Genetic disposition Glycolysis defect Lipid metabolism defects Mitochondrial myopathies Muscular dystrophies G-6-PD deficiency Collagen vascular disorders
Diagnosis History Deteriorating renal function Tea-colored urine Peaked T-waves Evidence of coagulopathies
Treatment IV fluids Electrolyte correction Acid-base correction Diuretics Dialysis or hemofiltration Correction of underlying problems
Adjuvant Therapy Fenoldopam N-acetylcysteine Nesiritide