The effects of orthostatism in adult intensive care unit patients

Abstract

Objective: To assess the consciousness level, pulmonary and hemodynamic effects of orthostatic position in intensive care patients. Methods: This study was conducted from April 2008 to July 2009 in the Adult Intensive Care Unit, Hospital das Clínicas, Universidade Estadual de Campinas, São Paulo, Brazil. Fifteen patients were included who were mechanically ventilated for more than seven days and had the following characteristics: tracheotomized; receiving intermittent nebulization; maximal inspiratory pressure of less than -25 cm H2O; Tobin score less than 105; preserved respiratory drive; not sedated; partial arterial oxygen pressure greater than 70 mm Hg; oxygen saturation greater than 90%; and hemodynamically stable. With inclinations of 0̈, 30̈ and 50̈, the following parameters were recorded: consciousness level; blinking reflex; thoracoabdominal cirtometry; vital capacity; tidal volume; minute volume; respiratory muscle strength; and vital signs. Results: No neurological level changes were observed. Respiratory rate and minute volume (VE) decreased at 30% and later increased at 50%; however, these changes were not statistically significant. Abdominal cirtometry and maximal expiratory pressure increased, but again, the changes were not statistically significant. Regarding maximal inspiratory pressure and vital capacity, statistically significant increases were seen in the comparison between the 50̈ and 0̈ inclinations. However, tidal volume increased with time in the comparisons between 30̈ and 0̈ and between 50̈ and 0̈. Mean blood pressure increased only for the comparison of 50̈ versus 0̈. Heart rate increased with time for the comparisons between 30̈ and 0̈, between 50̈ and 0̈ and between 50̈ and 30̈. Conclusion: Passive orthostatism resulted in improved tidal volume and vital capacity, maximal inspiratory pressure and increased heart rate and mean blood pressure in critically ill patients.