Appropriate attachments for delivering oxygen have
recently been reviewed;49 in resource limited settings, use of
nasal oxygen prongs is optimal but often limited by cost and
availability. They do not require humidification, and low flow
rates (0.5–2 litres/min) are effective in correcting hypoxaemia
in most infants. A nasopharyngeal catheter is the most
efficient method for delivering oxygen, providing the highest
partial pressure of alveolar oxygen for a given flow rate;
however, these are associated with higher complication rates
than nasal prongs and do require humidification. A nasal
catheter, inserted half way into the nasal passage, may be the
most widely used method in developing countries: low flow
rates are adequate, complications are rare, cost is a fraction of
that of nasal prongs, and, where oxygen catheters are
unavailable, nasogastric tubes are often used. Giving oxygen
through a tube directed into a head box is inefficient in
health facilities where oxygen supplies are limited. High flow
rates (.4 litres/min) are required to achieve a high fraction
of inspired oxygen and to avoid carbon dioxide accumulation
within a standard neonatal head box.