Maternal mortality from Mendelson's syndrome: an explanation?

There have been major changes in obstetric and anaesthetic practice since 1946, including the introduction of intravenous infusions, oxytocics, tocolytic drugs, and endotracheal intubation. Some of these may adversely affect pulmonary water balance, which is probably already altered by pregnancy. These changes may have contributed to the increased severity of Mendelson's syndrome in pregnancy and to some extent explain the failure of prophylaxis to reduce maternal deaths.