A new approach to artificial expansion and ventilation of the lung in the severely asphyxiated neonate.
In severe asphyxia, expansion of the newborn lung must precede ventilation by intermittent positive pressure. Inadequate expansion may lead to hypoxia and excessive expansion to rupture of the lung. The only way in which a predetermined pressure can be achieved, and not exceeded in the alveoli, is by applying that pressure at the mouth and waiting until all flow ceases. Applying pressure in this way and increasing it according to a "staircase" pattern, with appropriate steps at suitable intervals, should ensure that the maximum pressure produced in the alveoli is no greater than the minimum necessary for resuscitation in each individual infant. On the basis of published work, ranges of optimum values for the increments and time intervals are suggested. Clinical judgement is still necessary to select from within these ranges, but this "pressure staircase" method should provide a systematic approach to the problem. A suitable apparatus is described.