Acute Kidney Injury Part 1 PDF

Renal Part Acute Kidney Injury: Understanding and Management Learning Outcomes 1 AKI Types 2 Treatment 3 RRT Distinguish among different Apply different therapeutic Demonstrate knowledge types of acute kidney injury....

Renal Part Acute Kidney Injury: Understanding and Management Learning Outcomes 1 AKI Types 2 Treatment 3 RRT Distinguish among different Apply different therapeutic Demonstrate knowledge types of acute kidney injury. options for AKI treatment. about renal replacement therapy. Acute Kidney Injury Overview Definition Abrupt loss of kidney functions Effects Waste product retention, electrolyte disturbances, volume status changes Detection Change in biomarkers, such as serum creatinine (SCr) An increase in SCr often lags (48–72 hours) behind the onset of injury. =>  output wine AKI Classification e * Systems insin scr 1 RIFLE Risk, Injury, Failure, Loss, End-stage 2 AKIN Acute Kidney Injury Network 3 KDIGO Kidney Disease Improving Global Outcomes RIFLE Classification 1 Criteria Based on changes in serum creatinine and urinary output 2 Stages Risk, Injury, Failure, Loss, End-stage 3 Purpose Standardize definition and severity of AKI AKIN Criteria SCr Increase inpatient Percentage Increase Urinary OutputNormal 1-1 5. e 0.3 mg/dL over baseline within 50% or greater increase in SCr Less than 0.5 mL/kg/hour for 48 hours within 7 days more than 6 hours KDIGO Guidelines 1 SCr Increase 0.3 mg/dL within 48 hours 2 Percentage Increase 50% increase in SCr within the previous 7 days s Risk Factors for AKI Age Increased risk with advanced age Comorbidities HTN , Diabetes Presence of other health conditions Proteinuria Excess protein in urine blood of Major Surgery loss Increased risk post-operation  Types of AKI 90 · Pre-renal - Intrinsic Post-renal S Bloothey & ex is Hypo-perfusion to the kidney : shock Structural damage to the kidney ex = [Mecation 3 Obstruction of urinary outflow · HF infection. TB Pre-Renal Causes: Decreased Perfusion 1 Fluid Loss Inadequate intake, vomiting, diarrhea, fever 2 Blood Loss Trauma resulting in massive hemorrhage 3 Systemic Conditions Sepsis, heart failure, liver cirrhosis Medications Affecting Kidney Blood Flow Efferent Arteriole ACEI => & Drugs causing vasodilation & Prostaglandin Inhibition Drugs inhibiting vasodilatory prostaglandin synthesis Afferent Arteriole Drugs causing vasoconstriction - Intrinsic AKI Causes 1 Acute tubular injury antimicrobia Damage to kidney tubules van Join 2 Tubulointerstitial injury Inflammation of kidney tissue 3 Glomerulonephritis Inflammation of kidney filtering units Glomerular Causes of Intrinsic AKI 1 Autoimmune Disorders ⑪E Immune system attacking kidney tissue 2 Oncology Drugs Certain cancer treatments affecting glomeruli 3 Specific Medications Interferon, pamidronate, gemcitabine, VEGF inhibitors ----  Nephrotoxic contrast media Tubular Causes of Intrinsic AKI: Part 1 Antimicrobials Nephrotoxic Drugs Acute Tubular Necrosis Certain antibiotics can damage Various medications with Caused by ischemia or kidney tubules kidney-damaging effects exposure to nephrotoxins  Tubular Causes of Intrinsic AKI: Part 2 1 Aminoglycoside-associated ATN ( Occurs in 11%-60% of adults, 12% of neonates 2 Amphotericin B - > serving Can cause AKI in around 28% of cases & 3 Vancomycin Nephrotoxicity A topic of ongoing debate - 4 Contrast-induced Nephrotoxicity Occurs in 3%-30% of patients Vascular/Thrombotic Causes of Intrinsic AKI Vasculitis Malignant Hypertension Thrombotic Disorders Inflammation of blood vessels Severe high blood pressure Blood clotting issues affecting kidneys Interstitial Causes of Intrinsic AKI Infections Medications Immune Disorders Pyelonephritis, renal tuberculosis, Antibiotics, NSAIDs, diuretics Various autoimmune conditions fungal nephritis commonly implicated E affecting kidney interstitium s At o Post-Renal AKI: Obstruction Causes 1 Nephrolithiasis Kidney stones obstructing urine flow 2 Benign Prostatic Hypertrophy Enlarged prostate compressing urethra 3 Surgical Complications Post-operative issues leading to obstruction Post-Renal AKI Causes => Kidney Stones Obstruction by calculi Prostatic Hypertrophy Enlarged prostate blocking urine flow Retroperitoneal Fibrosis Scarring around kidneys and ureters Drug-Induced Crystalluria Mechanism Low solubility drugs crystallize in urine Effect Crystals obstruct the collecting system Risk Factors High drug doses, dehydration, acidic urine  Rish pos Risk ⑳ - - pie = Case Study Analysis: Potential Causes 1 Comorbidities Hypertension, diabetes, and gout increase AKI risk 2 Surgery Recent hemi-colectomy may affect kidney function 3 Medications Lisinopril and spironolactone can impact kidney function = - Clinical Workup A comprehensive evaluation of a patient's medical condition, including history, physical examination, and diagnostic tests. Medical History and Physical Examination Gather Identify Risk Physical Exam Information Factors Assess vital signs, Obtain details on fluid Look for signs of volume status, and any losses, previous lab heart/liver disease, evidence of underlying results, comorbidities, recent infections, or conditions. and medication history. prior urinary tract issues. uT frequent Labs Work Comprehensive lab testing is crucial for monitoring kidney function and guiding treatment in acute kidney injury. This includes regular assessment of electrolytes, kidney biomarkers, and other relevant tests. S may case hyperkalemia Phosphatemir cer ha Laboratory Studies Serum Chemistry Urinalysis Complete Blood Count Analyze blood samples to assess Evaluate urine composition and Measure red and white blood cell electrolyte and metabolic status. sediment to identify potential counts to detect abnormalities. issues. Radiographic Studies Imaging tests play a crucial role in the clinical workup, providing valuable insights into the underlying causes of acute kidney injury. Types of Radiographic Studies Renal Ultrasonography Evaluates the size, shape, and structure of the kidneys. - - Renal Doppler Ultrasonography - Assesses blood flow to the kidneys, helpful in diagnosing renal - & artery stenosis. Renal Biopsy - Obtains a small sample of kidney tissue for microscopic examination. Therapy for Acute Kidney Injury (AKI) Treat Underlying Cause 1 [ 3 Focus on addressing the root issue leading to AKI. Discontinue Nephrotoxins 2 Avoid substances that can further damage the kidneys. - Ensure Proper Perfusion 3 Monitor fluid status and blood pressure to maintain - kidney function. The KDIGO international guidelines on AKI outline these key treatment strategies to manage the condition effectively.  1253 e Fluid Replacement · 5 Crystalloids vs. Colloids Colloid Solutions Total Body Water Crystalloid solutions are more Colloid solutions like gelatins, Total body water volume is commonly used than colloids for dextrans, starches, and albumin approximately 40 L, or 60% of resuscitation in patients with pre- increase intravascular oncotic body weight, with extracellular - renal AKI. pressure and shift fluid into the fluid volume at 15 L (20% of body = vasculature. weight). · wipe ad Volum it Fluid Balance - The KDIGO Guideline Crystalloids Isotonic crystalloids are the fluid of choice for intravascular volume expansion. Avoid Hydroxyethylstarch Hydroxyethylstarch has been associated with adverse effects. Role of Colloids Colloids such as albumin may still play a role in patients requiring large - fluid volumes. - Diuretics Preventing and Managing Fluid Renoprotective Recommended Treating AKI Overload Effects Use Diuretics have long Volume overload is Studies have Loop diuretics are been a mainstay in common in AKI, and investigated the recommended for preventing and treating diuretics facilitate fluid - potential treating volume S acute kidney injury management. renoprotective effects overload and 6 - - (AKI). of furosemide in hyperkalemia as - reducing oxygen consequences of AKI. - - demand and clearing - necrotic debris. - Furosemite Vasopressors - [ Vasopressors are used to maintain adequate mean arterial pressure (MAP) for organ and tissue perfusion. Fluid resuscitation alone is often = insufficient, requiring vasoactive agents. Persistent hypotension, even after fluid resuscitation, increases the risk of acute kidney injury (AKI). Types of Vasopressors Receptor Profiles Norepinephrine => Dopamine Vasopressors have varying Commonly used = first-line Used for hypotension, but second- receptor affinities, leading to vasopressor - for most shock states line behind norepinephrine, with - different effects on due to its potent vasoconstrictor potential for tachydysrhythmias at - -o - - vasoconstriction, inotropy, and and inotropic effects. higher doses. - - chronotropy. Renal Replacement Therapy (RRT) Indications Prevalence Optimization ① - Anuria Required in 5-6% of critically ill patients Factors to consider include timing, - Acute fluid overload with AKI. modality, dose, and clearance. - - Severe hyperkalemia > Metabolic acidosis - BUN above 100 mg/dL Timing of RRT 1 Early Initiation - Clinical trial showed early RRT initiation reduced 90-day - mortality. 2 Volume Overload and Solute Imbalances - Most nephrologists start RRT for AKI patients with these issues. 3 Risk-Benefit Ratio Debate centers on the risks and benefits of early versus late RRT.  RRT Modality - main problem Intermittent Hemodialysis (IHD) solute 7 severe Renal support for 3-6 hours per session, 3-4 times weekly. ex hyperkdemin = or as needed Continuous Therapies Main => Delivered 24/7, providing a gentler, more prolonged problem Flulf treatment. Not Potent hemodynamically unstable - Hybrid Therapies Combine advantages of intermittent and continuous approaches. CRRT Advantages Hemodynamic Stability - Reduced Downtime ①[ CRRT provides better control of volume and solute removal, maintaining hemodynamic stability. 3 Downtime for procedures or tests may be reduced with CRRT compared to intermittent RRT. Drug Dosing In Dialysis Molecular Weight Smaller molecular weight substances pass through dialysis membrane more easily. & Protein Binding Highly protein-bound drugs have less unbound drug available for dialysis. Volume of Distribution Drugs with large volumes of distribution are poorly dialyzable. Dialysis Flow Rates m)/hr Higher dialysate flow rates increase dialysis clearance when drug levels are low. Common Dialyzable Drugs Dialyzable Drugs OSCE & s Drugs that can be effectively removed by dialysis include barbiturates, even s WhatsThe - lithium, isoniazid, salicylates, theophylline/caffeine, methanol, ethylene - - = - - - * glycol, and Depakote. - on * patient - the is Importance of Monitoring Dialysis 2 Careful monitoring of drug levels is crucial for patients on dialysis to. = ensure proper dosing and prevent toxicity. Dialysis Clearance The dialysis process can effectively remove these drugs from the body, making it an important consideration in managing patient care. Case Study Introduction 1 Patient 75-year-old man on surgical floor, urine output decreased over last few hours. 2 Vitals HR 116 BPM, BP 90/60 mmHg 3 History Right hemi-colectomy 4 hours ago for caecal tumor. Patient Medical History Conditions Medications Hypertension, Type 2 Diabetes Mellitus, Gout Lisinopril, Diclofenic acid, Allopurinol, Spironolactone Case Study: 75-year-old man (continued) The patient underwent a right hemi-colectomy 4 hours ago for a caecal tumor. He has a history of hypertension, type 2 diabetes, and gout. His current medications include lisinopril, diclofenac, allopurinol, and spironolactone.