Chlamydial Pneumonitis: A Creepy Neonatal Disease

Table 1

Respiratory indices.

Parameters	Data	Remarks
Ventilation index	N/A	Prognostic marker of lung injury (http://www-users.med.cornell.edu/~spon/picu/calc/ventindx.htm)
Alveolar-arterial oxygen gradient	<50.9	Impaired diffusion or shunting (http://www-users.med.cornell.edu/~spon/picu/calc/aagrad.htm)
Oxygenation index	3.7	Denotes risk of treatment (http://www-users.med.cornell.edu/~spon/picu/calc/oxyindex.htm)
PaO2/FiO2 ratio	>271	Severity of lung injury: ALI < 300, ARDS < 200 (http://easycalculation.com/medical/ALI.php)
𝑄𝑠/𝑄𝑡	<4%	Intrapulmonary shunt and V/Q mismatch, normally <5%; (http://www.medfixation.com/classic-shunt-equation-qsqt-calculation/)

𝑄_𝑠/𝑄_𝑡 = (CcO₂ − CaO₂)/(CcO₂ − CvO₂). The oxygen content of mixed arterial blood (CaO₂) is determined by the content of oxygen in the blood that reached ventilated alveoli (CcO₂), the content of oxygen in blood that bypassed ventilated alveoli (CvO₂), and the proportion of the two. CcO₂ is the content of oxygen in pulmonary capillary blood and is estimated by plugging in 100% as the saturation since the PcO₂ (pulmonary capillary PO₂) can be assumed to be high enough to assure 100% saturation.
Mean airway pressure in a spontaneous breathing neonate is assumed to be 10 cmH₂O.