The lytic effects of detergent sclerosants on erythrocytes, platelets, endothelial cells and microparticles are attenuated by albumin and other plasma components in vitro.

OBJECTIVE

To investigate the lytic effects of sodium tetradecyl sulphate (STS) and polidocanol (POL) on erythrocytes, platelets, endothelial cells and platelet-derived microparticle (PDMP) formation in vitro and the potential protective effects of serum albumin and agents such as procaine.

MATERIALS AND METHODS

The effects of sclerosants were studied in blood samples obtained from normal individuals. Absorbance densitometry was used to assess the lytic effects of sclerosants on blood cells and cultured human microvascular endothelial cells (HMEC) in plasma and in saline. PDMP were quantified by flow cytometry.

RESULTS

Haemolysis occurred in whole blood at sclerosant concentrations greater than 0.25% for STS and above 0.45% for POL. Similar concentrations of both agents caused platelet and endothelial cell lysis. Both sclerosants released PDMP at low concentrations but destroyed PDMP at higher concentrations. Albumin significantly reduced the lytic effect of both sclerosants on all cells but had a greater inhibitory effect on POL. Protamine at 0.01% had a neutralising effect on STS, whereas procaine and lignocaine showed no such activity.

CONCLUSIONS

Sclerosants at therapeutic concentrations lyse blood cells and endothelial cells in vitro. This effect is strongly reduced by serum albumin possibly contributing towards the low incidence of thromboembolic complications of sclerotherapy.