| Class | Crystalloid fluid |
|---|---|
| Chemistry |
"Balanced" crystalloid solution composed of several cation salts:- Sodium chloride (105 mmol/L)- Sodium lactate (29 mmol/L)- Potassium chloride (5 mmol/L)- calcium chloride (2 mmol/L)So, in total;, 131 mmol/L sodium, 112 mmol/L chloride, 5 mmol/L potassium and 2mmol/Lcalcium- pH 5.0- Calculated osmolality 278 mOsm/kg- Measured osmolality 260 mOsm/kg
|
| Routes of administration |
IV only |
| Absorption |
100% oral bioavailability; well absorbed
|
| Solubility |
pKa of sodium lactate is 3.78; all components have excellent water solubility.
|
| Distribution |
VOD=0.2L/kg, basically confined to the extracellular fluid(thus: 25% remains intravascular, 75% becomes interstitial)
|
| Metabolism |
Only the lactate is metabolised, producing H2O and CO2
|
| Elimination |
Eliminated renally, where specific reabsorption mechanisms in the renal tubule regulate the rate of sodium and chloride excretion
|
| Time course of action |
Half life is 20-40 minutes in healthy volunteers, longer in shock states and in mechanically ventilated patients (up to 8 hours)
|
| Target receptor |
As a resuscitation fluid, you could say that the target receptor is the baroreceptor |
| Mechanism of action |
Expands the extracellular fluid volume and changes the biochemistry of the body fluids |
| Clinical effects |
Volume expansion: - by 25% of the infused volume, after 25-30 minutes - below the circulatory reflex activation threshold - effect is greater during the infusion (prior to redistribution) Change in osmolality: - minimal; unnoticed by osmoreceptors Change in biochemistry: - trivial sodium depression (~0.5-1.0 mmol/L) - trivial chloride elevation (up by 1.5 mmol/L for every litre of Hartmanns) - increase in bicarbonate and base excess (up by 2-3 mmol/L) |
| Literature reference |
White & Goldhill (2010) |
| CICM details of understanding | Level 1 |
| Mentioned around Deranged Physiology |
Hartmann's compound sodium lactate, and Response to 1L of Hartmann's compound sodium lactate. Also see the common question on whether it will raise the lactate (spoiler: it won't) |
| Related SAQs |
Question 18 from the second paper of 2023 |