Measurements of pulmonary mechanics prior to the elective extubation of neonates

We measured total respiratory system compliance (C_RS) and resistance (R_RS) by the passive expiratory flow technique prior to the elective extubation of 61 neonates with a history of respiratory distress syndrome. Successful trials of extubation were characterized by a higher mean value of C_RS when compared to trials that led to reintubation (1.52 vs. 1.10 mL/cm H₂O, P = 0.004). Low values of C_RS (0.9 mL/cm H₂O or less) were invariably associated with extubation failure, whereas high values of C_RS (1.3 mL/cm H₂O or greater) were associated with extubation success in 94% of patients. A higher mean value of R_RS was recorded in the group of infants who failed extubation when compared to those who were successful (0.22 vs. 0.17 cm H₂O/mL/s, P = 0.042). We propose that measurements of pulmonary mechanics, particularly C_RS, may by useful in identifying infants who will be at risk for extubation failure. Pediatr Pulmonal 1990; 9:238–243.