AUTISM SPECTRUM DISORDERS FOLLOWING IN UTERO EXPOSURE TO ANTIEPILEPTIC DRUGS

Abstract

<h3>BACKGROUND</h3> The purpose of this study was to investigate changes in breathing pattern, neuromuscular drive (P_0.1), and activity of the sternocleidomastoid muscles (SCM) during a gradual reduction in pressure support ventilation (PSV) in patients being weaned off controlled mechanical ventilation. <h3>METHODS</h3> Eight non-COPD patients recovering from acute respiratory failure were included in this prospective interventional study. All patients were unable to tolerate discontinuation from mechanical ventilation. Each patient was evaluated during a period of spontaneous breathing and during PSV. Four successive levels of PSV were assessed in the following order: 20 cm H₂O (PS20), 15 cm H₂O (PS15), 10 cm H₂O (PS10), and 5 cm H₂O (PS5). <h3>RESULTS</h3> When pressure support was reduced from PS20 to PS10 the respiratory rate (f) and the rapid shallow breathing index (f/Vt) significantly increased and tidal volume (Vt) significantly decreased. These parameters did not vary when pressure support was reduced from PS10 to PS5. Conversely, P_0.1 varied negligibly between PS20 and PS15 but increased significantly at low PSV levels. P_0.1 values were always greater than 2.9 cm H₂O (4.1 (1.1) cm H₂O) when SCM activity was present. When contraction of the SCM muscles reappeared the P_0.1 was the only parameter that changed significantly. <h3>CONCLUSIONS</h3> In postoperative septic patients the value of P_0.1 seems to be more useful than breathing pattern parameters for setting the optimal level of pressure assistance during PSV.