[Effect of blood levels of carboxyhemoglobin (COHb) on erythrocyte filtration time in young smokers].

The effects of chronic exposure to carbon monoxide on some rheologic parameters (erythrocyte filtration time in particular) and on FEV1, and on FEF25-50 were studied in young smokers. A positive correlation among number of cigarettes day, COHb blood levels and erythrocyte filtration time was found. Packed red cell volume, fibrinogen concentration and platelet count were unaffected; no evidence of small-airway obstruction was observed. The alteration of erythrocyte deformability may be an early sign of hemorheological impairment which can progressively worse if high COHb blood levels are chronically maintained, with damaging effects on vessel function.