Colloid Preloading
Administration of colloid solutions before spinal anesthesia to prevent maternal hypotension. Less commonly used than crystalloid preloading due to cost and allergic risk.
Full Definition
Colloid preloading involves the intravenous administration of colloid solutions (such as albumin, hetastarch, or gelatin-based products) prior to spinal anesthesia in obstetric patients. The goal is to expand intravascular volume and prevent the hypotension that commonly follows sympathetic blockade. Colloids remain in the intravascular space longer than crystalloids due to their higher oncotic pressure, theoretically providing more effective volume expansion with smaller volumes. However, colloid preloading has largely been replaced by crystalloid solutions or co-loading techniques due to higher costs, potential for allergic reactions, and questionable superiority in preventing hypotension. When used, typical volumes range from 500-1000 mL administered over 15-30 minutes before the spinal block.
Usage
Usage note: Distinguish from 'co-loading,' which refers to simultaneous fluid administration with the spinal block.
In Context
- "The department discontinued routine colloid preloading due to cost concerns and equivalent outcomes with crystalloids." — Quality improvement report
- "Colloid preloading with 6% hetastarch was associated with a lower incidence of hypotension but higher material costs." — Research paper