Ventilation and Oxygenation

Many infants that come in to the NICU require oxygen support. There are many different way that oxygen can be delivered to the infants such as, nasal cannula, Oxygen hood, Nasal continuous positive airway pressure (NCPAP), Synchronized intermittent mandatory ventilation (SIMV), NCPAP with bump rate, and High frequency ventilation jet, and assist control method.
When infants are on nasal cannula they receive a small percentage oxygen and sometimes they only receive air. These babies are more stable and only require a little bit of assistance. Infant on a hood require a stronger oxygen concentration. The hood is shaped like a square and is placed over the infants head. The oxygen concentration can be adjusted up and down based on the needs of the baby. The infant must remain under the hood to have any type of oxygen concentration. Oxygen concentration can be as high as 100% ( FYI 21% is room air, what we breath normally). NCPAP consist of two prongs that are inserted into the infants nares. With NCPAP oxygen concentration can be adjusted from 21% to 100% the difference between NCPAP and the previous two is. NCPAP delivers pressure to keep the alveoli (the place were gas exchange occurs in the lungs) open. If the alveoli are unable stay open this would cause collapse of the lungs. On the SIMV setting the infant is intubated ( has tube down his mouth). On this setting a set oxygen concentration and a set pressure are delivered. This setting allows the infant to breathe spontaneously with out ventilator support. SIMV mode also delivers a set number of breath when the infant does not breathe with a set amount of pressure to keep the lungs open. NCPAP with bump rate is a combination of NCPAP and SIMV mode. The infant has the nasal prongs as in NCPAP and the set pressure as before but the ventilator delivers a set number of breaths to the infant regardless of when and if the infant breathes. When an infant is on a jet they are requiring alot of assistance. The jet delivers a large amount of a small number of breaths. The jet can deliver over 400 breaths per minute. On assist control method the ventilator delivers a set number breaths but also allows the infant to breath spontaneously. This mode is similar to SIMV however with the A/C mode when the infant breaths spontaneously the ventilator still support and by delivering the same amount of pressure he would receive if the ventilator breathed for him.

Reference:
Merenstein, G.B., Gardner, S.L. (2006). Handbook of Neonatal Intensive Care (6th ed.). St. Louis, MO: Mosby Elsevier.