Anestesia Analgesia Reanimación
Print version ISSN 0255-8122
PASTORINO, Mauricio; BAPTISTA, William and ZUNINI ¹, Graciela. Oxigenación arterial en el paciente Gran Quemado sometido a ventilación mecánica con patrones "no protectivos" durante la anestesia general. Anest Analg Reanim [online]. 2004, vol.19, n.1, pp. 31-39. ISSN 0255-8122.
Summary Here we report a prospective study aiming to quantify the disturbances of the hematosis in burned patients under non protective mechanical ventilatory patterns. We studied 19 patients going under balneotherapy or surgery for escharotomy and grafting. In 11 cases these patients were coursing pneumonia from mechanical ventilators or had airway injury. We applied a ventilatory pattern consisting of a current volume of 10 ml/kg, FIO2=1 and frequency adjusted for normocapnia. Neither inspiratory pause nor positive end expiration pressure were used. We measured the indexes paO2/FIO2, paO2/pAO2, and the arteriovenous difference in oxygen content (AVDO2). We observed a drop in all three indexes with statistical significance for the last two but not for the paO2/FIO2 30 minutes after induction. Two groups of patients showing pulmonary injury or without pulmonary injury (group A and B) finding a significant drop in the AVDO2 30 minutes after the induction for group B and a significant drop in all indexes for group A (p<0.05). These results may be explained because of an increase in the functional capacity due to the large current volumes used and the intrinsically generated positive pressure at the end of expiration. We conclude that the strategy of ventilation usually employed during general anesthesia in burned patients does impair arterial oxygen content in the population showing pulmonary injury and was as unable to prevent shunt and alterations in the index ventilation/perfusion.
Keywords : Burned patients; Mechanical ventilation; General Anesthesia; Disturbances of the arterial oxygen content.