334.3 🏥 內科專科考前版

334.3.1 Mechanistic Deep Dive

334.3.1.1 Solute Removal in Dialysis

  • Diffusion: concentration gradient
  • Convection: pressure gradient + ultrafiltration
  • Adsorption: surface binding (some membranes)
  • IHD: mostly diffusion
  • CVVH: convection
  • CVVHD: diffusion
  • CVVHDF: both

334.3.1.2 Citrate Metabolism

  • Calcium-citrate complex → liver (citric acid cycle)
  • Releases bicarbonate (alkalinizing)
  • Liver failure → accumulation
  • Monitor: ionized Ca, total Ca, gap (total/ionized > 2.5 → accumulation)

334.3.1.3 Anticoagulation Strategies

  • Systemic heparin: ↑ bleeding risk
  • Regional citrate: ↓ bleeding; complex monitoring
  • Argatroban: for HIT
  • No anticoag: low-flow, frequent flushes

334.3.2 Recent Trials & Updates

334.3.2.1 STARRT-AKI (2020)

  • N = 3019
  • Accelerated vs standard RRT initiation
  • No mortality benefit
  • Higher RRT dependency in accelerated

334.3.2.2 AKIKI 2 (2021)

  • Even more delayed strategy
  • Less RRT use
  • Not inferior

334.3.2.3 Empagliflozin Post-AKI

  • Emerging
  • May reduce CKD progression

334.3.2.4 REVOLUTE (2024) — Trial

  • Tolvaptan + furosemide in HF
  • Decongestion strategy

334.3.2.5 CARRESS-HF + ADVOR + TACTICS-HF (HF + RRT)

  • Diuretic resistance strategies

334.3.3 High-Yield Specialist Points

334.3.3.1 Hyperkalemia in AKI Management

  • ECG changes
  • Calcium gluconate (membrane stabilizer)
  • Insulin + glucose
  • Sodium bicarbonate (if acidemic)
  • β2-agonist (albuterol)
  • K binders: Kayexalate (older), patiromer, sodium zirconium cyclosilicate (SZC)
  • RRT for refractory or severe

334.3.3.2 Volume Resuscitation Choice

  • Crystalloid first-line
  • Balanced solutions (Lactated Ringers, Plasma-Lyte) > 0.9% saline (BaSICS, SMART trials)
  • Albumin: HRS, hypoalbuminemia, large-volume paracentesis
  • Avoid: hetastarch (renal failure risk)

334.3.3.3 Loop Diuretic Strategy

  • Furosemide IV (loading dose: 1-2× home oral dose)
  • Continuous infusion vs bolus (DOSE trial — equivalent)
  • Add thiazide (metolazone) for synergy
  • Acetazolamide (ADVOR) for diuretic resistance

334.3.3.4 Vancomycin Dosing in HD

  • Hold during dialysis day
  • Re-dose post-HD
  • Trough monitoring (15-20 if MRSA pneumonia/IE)
  • AUC-based dosing newer

334.3.3.5 Aminoglycoside Once-Daily in AKI

  • Extended-interval (5-7 mg/kg q24-48h)
  • Reduces toxicity
  • Therapeutic drug monitoring

334.3.3.6 Beta-Lactam Continuous Infusion

  • For critically ill with AKI
  • Improved time above MIC
  • Some trials show benefit

334.3.3.7 Phosphate in Refeeding Syndrome

  • Severe hypophosphatemia
  • Treat carefully (cardiac, respiratory failure)
  • Slow IV phosphate

334.3.3.8 Hypothermia Therapy + AKI

  • Post-cardiac arrest
  • Renal effects + careful management

334.3.3.9 TLS Prophylaxis Strategy

  • Risk stratification (Coiffier criteria)
  • Low/intermediate: allopurinol + hydration
  • High: rasburicase + hydration
  • During chemo

334.3.3.10 Sepsis-Induced AKI Management

  • Early antibiotics
  • Source control
  • Hemodynamic optimization
  • Avoid further nephrotoxins
  • Surviving Sepsis Campaign guidelines

334.3.3.11 Recovery After Severe AKI

  • Post-AKI clinic
  • Periodic eGFR + UACR
  • Avoid future insults
  • Address modifiable factors (BP, DM, weight)
  • ACE/ARB if indicated

334.3.4 Pearls

  • AKI principles: address cause + supportive + RRT
  • AEIOU: indications for RRT
  • STARRT-AKI 2020: no benefit early RRT
  • CRRT > IHD for hemodynamically unstable
  • Citrate > heparin if bleeding/HIT
  • Disequilibrium: slower initial sessions
  • Removable toxins: methanol, ethylene glycol, lithium, salicylate, metformin
  • Post-AKI: ↑ CKD risk; surveillance critical