Lung mechanics during and after extracorporeal membrane oxygenation for meconium aspiration syndrome.

OBJECTIVE

To determine whether abnormalities in lung mechanics detected in infants during the acute phase of meconium aspiration syndrome persist after treatment with extracorporeal membrane oxygenation (EMCO).

DESIGN

Prospective, descriptive study. Prospective evaluation of airway function and lung mechanics during and after ECMO by pulmonary function testing at 1.8 +/- 0.5 days of EMCO (period 1), follow-up at 1.4 +/- 0.2 days (period 2), and 7.0 +/- 0.9 days (period 3) after decannulation from ECMO.

SETTING

Tertiary care neonatal/pediatric ICU.

PATIENTS

Twelve neonates undergoing ECMO treatment for severe meconium aspiration syndrome that was refractory to conventional mechanical ventilation.

INTERVENTIONS

Maximum expiratory flow-volume curves were studied with the deflation flow-volume curve technique, and compliance and resistance of the respiratory system were studied with partial passive flow-volume curves.

MEASUREMENTS AND MAIN RESULTS

Respiratory system compliance was the only index of respiratory mechanics that was significantly (p less than .05) improved (0.96 +/- 0.1 vs. 0.61 +/- 0.1 mL/cm H2O/kg) immediately after decannulation from ECMO compared with period 1. Clinically important (p less than .05) improvement in forced vital capacity (28.0 +/- 5.5 vs. 16.1 +/- 1.9 mL/kg), respiratory system compliance (1.01 +/- 0.2 vs. 0.61 +/- 0.1 mL/cm H2O/kg), and maximum expiratory flow at 25%/forced vital capacity (1.0 +/- 0.3 vs. 2.2 +/- 0.3) was evident only during period 3 compared with period 1.

CONCLUSIONS

We conclude that improvements in the clinical condition and oxygenation, permitting successful decannulation from ECMO, are achieved before clinically important improvements in lung mechanics.