---
tags: tier1, PGY1
---
# Sodium
> [Tier 1 knowledge topics](/AoUNT7MtS3iso3e6iPOy9g)

Serum sodium in normal physiology is an indicator of volume status

## Hyponatremia

Below is an easy algorithm for evaluating hyponatremia

%%{ init: { 'flowchart': { 'curve': 'monotoneY'}}}%%
flowchart TD
   %%hypona[Hyponatremia<br/>Na<132] --> q1{Natura?}
   q1{Real?}
   %%q1 ---->|sOsms>290| pseudo[Pseudohyponatremia<br/>]
   q2{ADH\nfa:fa-toggle-off or fa:fa-toggle-on}
   q1 -->|sOsms<290| q2
   %%q2 --> adhoff["ADH Off"]
   aoddx[("1#176; Polydipsia<br/>Beer Potomania<br/>Tea and Toast")]
   q2 --->|UOsms<100|aoddx
   q2 -->|UOsms>100| UNa{RASS\nfa:fa-toggle-off or fa:fa-toggle-on}
   UNa -->|UNa>40| HUNa[(SIADH\nAdrenal Insufficiency\nHypothyroidism)]
   UNa -->|UNa<25| LUNa[(Hypovolemia\nCirrhosis\nHF)]

:::danger
:exclamation: Only correct Na by **6-8**mEq/24hr
:::

### Resources
- Easy hyponatremia download ([SVG](https://kroki.io/mermaid/svg/eNqNkV1PwjAUhu_9FSczS-Bikc2vqMsMSgwkZhA-rgYXR9qyJlsLbVEX5n-3KwtRr7w6PV_P-7ZlhfxY56gMzAdnAOD7ebWVArOhC0bRkmP8pi6SFOPwMlpBECSwCw8pmr3Cx69myaZTisUx8f1daIfsWK3HutRJdNerYavpnshs4kL-l71ylOjQHwyXguE9w8DIzaaggWQMpILfNdGqwkkkdiK7qDUQOZdIcrueeZYKY8Y8p4KSkM-s44Xn4e3NA0xkURG-1a2RJ0qVrRlZomhLc4qAgsBcojZet7UK7oILpx32erXDnlptJ2k6sEjxMO3PZv-_md04QlJMrixhaA9ZZzZyz9MnigosYCT0njG-5lSsq6Vo_svklZKccF0ebf7gxNF1Da-O00y-y6J5_KV45krlUnNtCS_d1Tfz5Kf9) | [PNG](https://kroki.io/mermaid/png/eNqNkV1PwjAUhu_9FSczS-Bikc2vqMsMSgwkZhA-rgYXR9qyJlsLbVEX5n-3KwtRr7w6PV_P-7ZlhfxY56gMzAdnAOD7ebWVArOhC0bRkmP8pi6SFOPwMlpBECSwCw8pmr3Cx69myaZTisUx8f1daIfsWK3HutRJdNerYavpnshs4kL-l71ylOjQHwyXguE9w8DIzaaggWQMpILfNdGqwkkkdiK7qDUQOZdIcrueeZYKY8Y8p4KSkM-s44Xn4e3NA0xkURG-1a2RJ0qVrRlZomhLc4qAgsBcojZet7UK7oILpx32erXDnlptJ2k6sEjxMO3PZv-_md04QlJMrixhaA9ZZzZyz9MnigosYCT0njG-5lSsq6Vo_svklZKccF0ebf7gxNF1Da-O00y-y6J5_KV45krlUnNtCS_d1Tfz5Kf9))