DYNAMIC HYPERINFLATION - COMPARISON OF JET VENTILATION VERSUS CONVENTIONAL VENTILATION IN PATIENTS WITH SEVERE END-STAGE OBSTRUCTIVE LUNG-DISEASE

Positive pressure ventilation in patients with obstructive lung diseas e may result in over-inflation of the relatively compliant lungs, resu lting in dynamic hyperinflation (DHI), Using a crossover trial design, we compared high-frequency jet ventilation (HFJV) versus ''optimal'' intermittent positive pressure ventilation (IPPV) in ten patients unde rgoing lung transplantation for severe, end-stage obstructive lung dis ease. We measured haemodynamics and the degree of DHI after both modes of ventilation, There were no significant differences between IPPV an d HFJV, with respect to efficiency of ventilation (PalphaCO2), haemody namic effects (stroke volume, blood pressure and cardiac output), or l ung hyperinflation (trapped gas volume). This study suggests that HFJV , when compared with optimal IPPV, is no better at minimizing DHI in p atients with severe, end-stage obstructive lung disease.