Intraesophageal pressure monitoring and the severity of respiratory distress syndrome.

The intraesophageal pressure difference (delta Pes) was measured in 46 preterm infants, 36 with respiratory distress (RDS). It was 12.7 +/- 2.9 mm Hg (mean +/- SEM) in severe RDS, 9.6 +/- 3.2 mm Hg in moderate RDS, and 5.2 +/- 1.6 mm Hg in infants with mild disease, measured at the age of 8 h. These intergroup differences were highly significant (P less than 0.001). During the first 96 h of life the delta Pes decreased to 6.1 +/- 1.1 mm Hg in severe RDS and to 4.8 +/- 1.2 mm Hg in moderate RDS. These changes were also highly significant (P less than 0.001) when compared with respective initial values. In infants with mild disease and in healthy preterm infants, the delta Pes did not alter significantly during the first 96 h of life. The correlations between gastric aspirate L/S ratio and the delta Pes at the age of 8 h (r = -0.65, P less than 0.001) and at the age of 24 h (r = -0.73, P less than 0.001) were highly significant. It is concluded that intraesophageal pressure monitoring is a valuable tool in the intensive care evaluation of the severity of RDS.