How is the high-volume strategy achieved when the goal is to deliver a high lung volume to a neonate receiving HFV?

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One method is to increase the distending pressures ( 11eb6937_bd35_0ba3_bb3a_e3cf8484a23e_TB8261_11 or CDP) in small increments (1 to 2 cm H₂O) while watching for improvement in oxygenation (arterial blood gas determinations, transcutaneous carbon dioxide, or pulse oximetry saturations) and mean lung volumes (MLV) determined by chest radiograph. Mean airway pressure is increased until oxygenation improves significantly or until MLV reaches desired levels, or both, which may be determined by the presence of a well-inflated lung on a radiograph (see Figure 17-6 in the textbook). While using this method, care must be taken to anticipate silent lung recruitment and to reduce 11eb6937_bd35_0ba4_bb3a_77eca3a575d5_TB8261_11 as appropriate to avoid serious impairment to venous return and reduction in cardiac output. Silent lung recruitment is gradual lung inflation taking place with static 11eb6937_bd35_0ba5_bb3a_83881f17d6f3_TB8261_11 settings (see Figure 17-7 in the textbook). Clinical clues heralding this include rapid improvements with subsequent unexplained decrements in oxygenation, decreasing PaCO₂ without changes in oscillatory amplitude (improving compliance), and, finally, clinical changes in perfusion. These problems often can be avoided with diligence and anticipation. Silent recruitment, although more common during initial HFV management, can occur any time attempts are made to optimize MLV. Data confirm the pulmonary, central nervous system, and cardiovascular safety and efficacy of this technique.

How Is the High-Volume Strategy Achieved When the Goal Is