Pertussis is a contagious disease that may develop a serious clinical picture by hypoxemia and pulmonary hypertension refractory to treatment. The syndrome of hyperviscosity and arteriolar thrombosis is responsible for the cardiocirculatory collapse. Our objective is to describe the evolution of a series of patients with severe pertussis, some of whom received exchange transfusion (ET) as an alternative treatment. We analyzed 41 patients' clinical charts with diagnosis of pertussis treated in the Pediatric Intensive Care Units during the 2003-2011 period. The mean age was 2.38 months. In the 90.2% of cases, the cause of admission to PICU was respiratory failure; 75% required mechanical respiratory support and 39% developed pulmonary hypertension. The overall mortality was 41.4%. Nine patients were treated by ET, 5 died. Conclusion. Severe pertussis is associated with high mortality. ET reduced the mass of circulating leukocytes in 53.5%; ET could be an alternative to conventional treatment, although controlled studies are required to assert it.