Llewellyn, M. A., Tilak, K. S., and Swyer, P. R. (1970). Archives of Disease in Childhood, 45, 453. A controlled trial of assisted ventilation using an oro-nasal mask. A controlled study was performed to assess the effect of early assisted ventilation using a tight fitting face mask. Early mask ventilation reduced the number of infants requiring intubation, but did not significantly alter the s...