Am. J. Respir. Crit. Care Med., Volume 156, Number 4, October 1997, 1185-1189

Effect of Prone and Supine Positions on Functional Residual Capacity, Oxygenation, and Respiratory Mechanics in Ventilated Infants and Children

ANDREW H. NUMA, JÜRG HAMMER, and CHRISTOPHER J. L. NEWTH

Pediatric Intensive Care Unit, Children's Hospital Los Angeles, Los Angeles, California

Although numerous reports have described the improvement in PA_O2 in patients in the prone position, the underlying mechanism has yet to be determined. Some authors have suggested this phenomenon may be related to an increase in functional residual capacity (FRC); however, no previous studies have described positional changes in FRC in children with severe lung disease or in those under neuromuscular blockade. We measured arterial blood gases, FRC, R_rs, and C_rs in supine and prone positions in 30 patients under neuromuscular blockade with lung disorders including moderately severe restrictive (n = 10) and obstructive (n = 10) disease and control subjects without significant lung disease (n = 10). Prone positioning was not associated with a significant increase in FRC in the cohort of 30 patients, nor in any of the subgroups. Although individual patients demonstrated large improvements in oxygenation, a statistically significant (but clinically insignificant) increase in AaPO₂ ratio was observed only in the subgroup of patients with obstructive disease (0.35 ± 0.03 to 0.38 ± 0.04, p = 0.027). There was no correlation between changes in FRC and changes in AaPO₂ (r = 0.225, p = 0.23). A significant improvement in R_rs occurred in the prone position compared to supine in patients with obstructive lung disease, decreasing from 0.264 ± 0.024 to 0.216 ± 0.021 cm H₂O/ml/s, p = 0.009. No significant changes in C_rs were seen in the prone position. We conclude that prone positioning has no effect on FRC and in this series of 30 patients significantly improved oxygenation only in patients with obstructive airway disease. A significant decrease in R_rs in patients with obstructive lung disease was also observed.

This article has been cited by other articles:

				M. A. Q. Curley, P. L. Hibberd, L. D. Fineman, D. Wypij, M.-C. Shih, J. E. Thompson, M. J. C. Grant, F. E. Barr, N. Z. Cvijanovich, L. Sorce, et al. Effect of Prone Positioning on Clinical Outcomes in Children With Acute Lung Injury: A Randomized Controlled Trial JAMA, July 13, 2005; 294(2): 229 - 237. [Abstract] [Full Text] [PDF]

				M. Rohdin, J. Petersson, P. Sundblad, M. Mure, R. W. Glenny, S. G. E. Lindahl, and D. Linnarsson Effects of gravity on lung diffusing capacity and cardiac output in prone and supine humans J Appl Physiol, July 1, 2003; 95(1): 3 - 10. [Abstract] [Full Text] [PDF]

				R. Y. Bhat, J. A. Leipala, N. R.-P. Singh, G. F. Rafferty, S. Hannam, and A. Greenough Effect of Posture on Oxygenation, Lung Volume, and Respiratory Mechanics in Premature Infants Studied Before Discharge Pediatrics, July 1, 2003; 112(1): 29 - 32. [Abstract] [Full Text] [PDF]

				S. M. Haefner, S. L. Bratton, G. M. Annich, R. H. Bartlett, and J. R. Custer Complications of Intermittent Prone Positioning in Pediatric Patients Receiving Extracorporeal Membrane Oxygenation for Respiratory Failure Chest, May 1, 2003; 123(5): 1589 - 1594. [Abstract] [Full Text] [PDF]

				P. Pelosi, N. Bottino, D. Chiumello, P. Caironi, M. Panigada, C. Gamberoni, G. Colombo, L. M. Bigatello, and L. Gattinoni Sigh in Supine and Prone Position during Acute Respiratory Distress Syndrome Am. J. Respir. Crit. Care Med., February 15, 2003; 167(4): 521 - 527. [Abstract] [Full Text] [PDF]

				P. Pelosi, L. Brazzi, and L. Gattinoni Prone position in acute respiratory distress syndrome Eur. Respir. J., October 1, 2002; 20(4): 1017 - 1028. [Abstract] [Full Text] [PDF]

				A. H. NUMA, G. D. WILLIAMS, and C. J. DAKIN The Effect of Nebulized Epinephrine on Respiratory Mechanics and Gas Exchange in Bronchiolitis Am. J. Respir. Crit. Care Med., July 1, 2001; 164(1): 86 - 91. [Abstract] [Full Text] [PDF]

				M. Baldauf, P. Silver, and M. Sagy Evaluating the Validity of Responsiveness to Inhaled Nitric Oxide in Pediatric Patients With ARDS : An Analytic Tool Chest, April 1, 2001; 119(4): 1166 - 1172. [Abstract] [Full Text] [PDF]

				M.G. Morris, P. Gustafsson, R. Tepper, M. Gappa, and J. Stocks The bias flow nitrogen washout technique for measuring the functional residual capacity in infants Eur. Respir. J., March 1, 2001; 17(3): 529 - 536. [Abstract] [Full Text] [PDF]

				A. Kornecki, H. Frndova, A. L. Coates, and S. D. Shemie 4A Randomized Trial of Prolonged Prone Positioning in Children With Acute Respiratory Failure Chest, January 1, 2001; 119(1): 211 - 218. [Abstract] [Full Text] [PDF]

				J. INGIMARSSON, A. THORSTEINSSON, A. LARSSON, and O. WERNER Lung and Chest Wall Mechanics in Anesthetized Children . Influence of Body Position Am. J. Respir. Crit. Care Med., August 1, 2000; 162(2): 412 - 417. [Abstract] [Full Text] [PDF]