Daily evaluation and spontaneous respiratory test for shorter times in paediatric mechanical ventilation

INTERVENTION: All patients from the test group were submitted to a daily evaluation performed every morning by an intern not involved with the decision of extubation. This evaluation considered the following information: absence of new infiltrates according to the thoracic x‐ray, fraction of inspired oxygen (FiO2) less than or equal to 50%, positive end expiratory pressure (PEEP) less than or equal to 8 cm H2O, inspiratory pressure (Pinsp) less than 25 cm H2O, presence of respiratory drive, absence of neuromuscular blocker in the last 24 hours, correction of hydrolytic changes (calcium, phosphorus, magnesium, potassium), haemodynamic stability (use of sodium nitroprusside, dopamine and dobutamine up to 10 µg/Kg/min), no continuous sedation, and haemoglobin greater than or equal to 8 g/dL. This evaluation was performed daily until the patient was extubated. Patients in the test group who fulfilled the daily evaluation were submitted to a spontaneous respiratory test with PEEP 5 cm H2O, pressure support of 10 cm H2O and FiO2 used before the test, for a period of two hours. The test was interrupted whenever patients presented any of the criteria characteristics of a faulty test: increase in respiratory frequency 20% above the initial value, signs of increased respiratory work (use of accessory muscles and paradoxical respiration), cardiac frequency 20% above the initial value, changes in consciousness level (restlessness or sleepiness), arterial pressure less than 5th percentile for patient's age, saturation less than 90%, gas carbonic arterial pressure (PaCO2) greater than 50 mmHg or an increase above 10 mmHg in 1 hour in chronic patients. Right before the test and in the first hour of the test, two arterial blood gas analysis were collected. If the patient did not meet any of the criteria of a faulty test, extubation was performed. Otherwise, mechanical ventilation was re‐established according to the previous parameters and the test repeated in 24 hours. The respiratory test CONDITION: Acute respiratory insufficiency ; Respiratory ; Postprocedural respiratory disorders, not elsewhere classified PRIMARY OUTCOME: Duration of mechanical ventilation compared to weaning, measured at time of extubation SECONDARY OUTCOME: Measured 48 hours after extubation:; 1. Faulty extubation rate; 2. Need for post‐extubation non‐invasive mechanical ventilation INCLUSION CRITERIA: 1. Children aged between 28 days and 15 years old, either sex 2. Admitted to the Hospital das Clínicas da Universidade de São Paulo ‐ HCFMUSP and Hospital Universitário, Brazil, between July 2007 and July 2009 3. Underwent mechanical ventilation for a period over 24 hours