Starches are glucose polymers containing mainly amylopectin (branched glucose chains) that has been etherified with hydroxyethyl groups, i.e. R-C-O-C2H3 groups.
There are several starches available and they differ in the degree of etherification. Hexastarch is more etherified than pentastarch, which is more etherified than tetrastarch.
Starches are presented as isotonic 6% solutions in 0.9% NaCl with average molecular weight 200 000.
Maximum recommended daily volume is 2500 ml.
The high molecular weight of starch and slow elimination from plasma, produces a longer-lasting plasma expansion than is seen with gelatins and dextrans. Their half-life in the plasma may be several days.
Table 1 shows the different starches available.
There is also a hypertonic solution.
Hexastarch |
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Pentastarches |
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Tetrastarch |
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Hetastarch |
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Table 1 Different starches available.
Caution: The starches are removed only slowly from the body by the reticulo-endothelial system.
Hypertonic solution
HyperHAES (Fresenius Kabi) is a 6% solution in 7.5% NaCl.
This hypertonic solution is designed specifically for rapid resuscitation; a single dose of 4 ml/kg rapidly over 5 minutes should then be followed by appropriate fluid replacement.
Caution: The starches are removed only slowly from the body by the reticulo-endothelial system.