Update March 7, 2018
The absence of cyanosis, a respiratory rate greater than 8/min and less than 20/min, the presence of breath sounds on auscultation of the chest, absence of wheezing and the results of arterial blood PO2 > 90 mm Hg and PCO2 <40 mm Hg means thsat there is adequacy of ventiulation.
If any of these is absent , the patient should be ventilated mechanically.
The resistance of the small airways of children may increase dramatically with subtle reductions in airway diameter.
Equipment factors may significantly contribute to dead space ventilation in children.
High-frequency oscillation remains an option for refractory respiratory failure in paediatrics.
Neurally adjusted ventilatory assist technology, while not in routine use in paediatrics, may benefit select patients.
With appropriate sizing, both cuffed and uncuffed tracheal tubes are acceptable for use in infants. Cuff pressures should be <20 cm H2O, and uncuffed tubes should allow for air leak at ∼20 cm H2O.
Orotracheal intubation vs nasal intubation in infants are commonly used.
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A number of methods for estimating appropriate TT size in paediatrics exist, including measurement of the fifth finger or fingernail. However, estimations based on body size may be inaccurate as airway growth tends to occur in a relatively constant fashion, independent of individual body habitus. It is likely for this reason that age-based formulas have been shown to more reliably predict appropriate TT size. The most commonly used is Cole's formula, which predicts an uncuffed TT size=[(age in years)/4+4]. If a cuffed TT is being placed, the predicted size would be 0.5 mm smaller than the uncuffed calculation.
It should be recognized that infant-sized TTs have proportionally higher resistances to flow compared with those used in adults. For example, a 6-month-old infant weighing 7 kg would be anticipated to require a 4.0 uncuffed or 3.5 cuffed TT. Compared with a 70 kg adult male intubated with an 8.0 TT, the resistance of a 4.0 TT is 16-times higher, and a 3.5 TT is 27-times higher (based on Poiseuille's law). In addition, while being ventilated, small reductions in TT diameter (such as due to secretions or bending) will have a more pronounced effect on smaller sized TTs. As a result, even minute changes to TT patency or position may significantly compromise the ventilation of infants and small children. Finally, due to the higher resistance of smaller tubes, infants require additional pressure support when breathing spontaneously while intubated.