The 1950s saw widespread polio epidemics, which were traditionally treated by placing patients in negative pressure ventilators ("iron lungs").  In the early 1950s, Lassen and colleagues began using positive pressure ventilation for these patients in Copenhagen, but iron lungs remained a standard treatment for neuromuscular ventilatory failure.  During his time at Queen Square, Dreifuss was a pioneer in the use of positive pressure mechanical ventilation for patients with poliomyelitis and the Guillain-Barré syndrome.  In their first report, Dreifuss and colleagues discussed a patient (who must have had post-polio syndrome before it was described) who benefitted from positive pressure ventilation when negative pressure devices were inadequate.  Their second report discussed 10 patients with acute polyneuritis who benefitted from positive pressure ventilation.

When Dreifuss arrived at the University of Virginia, he began a long, untimely successful campaign to replace iron lungs with positive pressure ventilators.   When I began working there in 1990, however, I switched the last remaining patient from a cuirass device to positive pressure ventilation, completing the transition.