Pulmonary volume recruitment restores pulmonary compliance and resistance in anaesthetized young children

Background : Oxygenation and gas exchange are impaired after induction of general anaesthesia. A timed re-expansion inspiratory manoeuvre (TRIM) improves pulmonary compliance and reverses haemoglobin oxygen desaturation rapidly in lambs. Methods : Twenty children of less than 2 years of age were given a standardized ventilated general anaesthetic. After 15 min of anaesthesia they were randomized to receive either a TRIM or 100% oxygen for 3 min. Dynamic pulmonary compliance and airway resistance were measured. Results : Pulmonary compliance fell by 12% and airway resistance rose by 12% during 15 min of ventilated general anaesthesia. 100% oxygen caused a further fall of 9% in compliance (P =0.016), whilst TRIM resulted in a 30% increase in compliance (P < 0.01). The changes in airway resistance with 100% oxygen and TRIM were not statistically significant. Conclusions : This study shows that TRIM increases pulmonary compliance during standardized ventilated general anaesthesia.