Diaphragmatic Tissue Doppler Imaging During a Spontaneous Breathing Trial to Predict Extubation Failure in Preterm Infants
Weaning from mechanical ventilation is a critical issue and the diaphragmatic disfunction has been demonstrated to play an important role in extubation failure. the aim of present investigation is to evaluate diaphragmatic excursion velocity during in patients undergoing spontaneous breathing trial through tissue Doppler analysis in both inspiration and expiration.
• premature infants with gestational age \<32 weeks and supported by invasive mechanical ventilation ≥48 hours
• All the indications for extubation are met：cough or vomiting due to spontaneous breathing and sputum aspiration; ventilator parameters in recent 24 hours: MAP \< 8cmH2O, RR \< 30 times/min, FiO2 \< 30%; Arterial blood gas: pH \> 7.25, (PaCO2\< 60mmHg, BE \< 8mmol/L, oxygen saturation \> 90%
• a successful SBT
• parents or legal guardians sign informed consent to attend this study