On the very first, successful, long-term, large-scale use of IPPV
ABSTRACT
An “unprecedented respirator patient load at Los Angeles County Hospital [LACH] in 1948 (294 respirator cases)” arose from a seasonal increase in poliomyelitis cases to nearepidemic proportions. A finding by physician Albert Bower and his team that respiratory acidosis was frequent in patients receiving intermittent negative pressure ventilation (INPV), together with their awareness of a previous high mortality rate due to the standard treatment of polio ventilatory failure with Drinker–Collins respirators, led to multiple advances in equipment technology for LACH. Most important was biomedical engineer V Ray Bennett’s positive pressure respirator attachment, in use after September 1948, which converted an INPV machine, the Drinker, into one capable of supplying “intratracheal” intermittent positive pressure ventilation (IPPV), supplementary to its NPV. Together with their teams, Bower and Bennett used this attachment for 73 of 1949’s 130 “respirator cases”, to establish the first-ever large-scale long-term success of IPPV for respiratory failure in acute polio. In 1949, they demonstrated the superiority of (supplemental) IPPV over INPV alone, achieving a survival rate of 83.7% (108/129) — compared with the 21.1% survival rate in 1946 among the 38 patients ventilated that year.
A complete system of respiratory care was developed for polio victims at LACH, setting levels of treatment and expertise distinctly higher, by 1950, than was current at other known polio respiration units, and preceding the well known developments in Copenhagen in the early 1950s. Extensive experience was obtained by a consistent medical staff, working as a team, in one hospital. Bower and Bennett deserve greater recognition of their pioneering merit than they currently receive in the written history of intensive care medicine.
Crit Care Resusc 2007; 9: 91–100
