Can we build tools to help with the algorithmic way of assessing hyponatremia?

Below is a mermaid diagram from some a chalk talk that an emergency department / ICU attending gave on hyponatremia assessment.

graph TD
    A[Hyponatremia] --> B{Serum Osmolality}
    B -->|Hypertonic: >295 mOsm/kg| D[Hyperglycemia or Other Osmotic Agents]
    B -->|Isotonic: ~275-295 mOsm/kg| C[Pseudohyponatremia]
    B -->|Hypotonic: <275 mOsm/kg| E{Urine Osmolality}
    E -->|<100 mOsm/kg| F[Primary Polydipsia \n Low Solute Intake]
    E -->|>100 mOsm/kg| G{Urine Sodium}
    G -->|<20 mEq/L| H[Volume Depletion: Renal or Extrarenal Losses]
    G -->|>20 mEq/L| I[SIADH\nAdrenal Insufficiency\nHypothyroidism]

Mermaid diagram from ChatGPT

graph TD
    A[Hyponatremia] --> B{Assess volume status}
    
    B --> C1[Volume Depletion]
    B --> C2[Euvolemic]
    B --> C3[Volume Overload]

    C1 --> D1{Urine Sodium <20 mEq/L?}
    D1 --> E1[Extrarenal Salt Losses]
    D1 --> E2[Renal Salt Losses]

    C2 --> D2{Urine Osmolality?}
    D2 --> E3[Urine Osm <100 mOsm/kg: Primary Polydipsia]
    D2 --> E4[Urine Osm >100 mOsm/kg]

    E4 --> F1{Urine Sodium?}
    F1 --> G1[Urine Sodium <20 mEq/L: Reset Osmostat]
    F1 --> G2[Urine Sodium >20 mEq/L]

    G2 --> H1[SIADH]
    G2 --> H2[Hypothyroidism]
    G2 --> H3[Adrenal Insufficiency]

    C3 --> D3{Urine Sodium <20 mEq/L?}
    D3 --> E5[Heart Failure, Cirrhosis, Nephrosis]
    D3 --> E6[Acute/Chronic Renal Failure]

Cheers,
Erkin
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