In this protocol we will conduct a randomized controlled trial where babies with respiratory
distress syndrome (RDS) who have not yet reached criteria for intubation, will be randomized
to receive surfactant by LMA or to continue receiving standard therapy of nasal CPAP and
supplemental oxygen. All babies will be given surfactant by endotracheal tube if they reach
"failure" criteria, which is the standard criterion for surfactant administration (i.e.,
FiO2= 65% while receiving nasal CPAP).
The objective of this RCT is to determine if surfactant can be successfully administered by
LMA, thus perhaps avoiding the need for endotracheal intubation. The hypothesis is that
fewer babies in the LMA group would reach failure criteria.
Neonatal respiratory distress syndrome (RDS) is an illness of prematurity that results from
insufficient surfactant in the lungs. Standard therapy for RDS is to place the baby in an
oxygen hood or on nasal CPAP with supplemental oxygen, and if more than approximately 60%
oxygen is required, an endotracheal tube is placed and a surfactant solution is injected
into the tube.
An LMA is an FDA-approved, commercially-available device that is commonly used to substitute
for an endotracheal tube.(1) The device consists of a tube, similar to an endotracheal
tube, which has an inflatable donut-shaped cap at one end. The cap end of the LMA is placed
through the mouth so that it lies over the larynx and the cap is then inflated. The opening
of the tube is then proximal to the opening of the larynx and is sealed off from other
structures that open into the pharynx (e.g., the esophagus). The other end of the LMA can
then be attached to a resuscitation bag or mechanical ventilator to provide lung inflation.
This is a randomized controlled trial, where babies with moderate RDS, who have not received
surfactant prophylaxis and have not yet required endotracheal intubation and who are large
enough to accept an LMA, will be randomized either to receive surfactant by LMA or to be
managed under standard protocol. Infants who weigh > 1200 gms and have been diagnosed with
respiratory distress syndrome and have only minimal to moderate lung disease (i.e.,
currently receiving nasal CPAP and requiring 30-60% supplemental oxygen) will be eligible.
After consent has been obtained, an envelope will be opened and the infant will be assigned
to either the "LMA" or the "Standard" group.
Those in the "LMA" group will have an LMA inserted by routine technique, the cuff will be
inflated, and the baby's respirations will be gently assisted with a flow-inflating
anesthesia bag. When it is evident from physical examination and pulse oximetry that
respiratory support is stable, the standard volume of Infasurf surfactant (3 mL/kg) will be
injected in 2-4 aliquots into the proximal end of the LMA. Each aliquot will be followed by
gentle positive-pressure assistance from the anesthesia bag until the surfactant has
disappeared from the tube, and the infant will then be rotated to another position prior to
the next aliquot. A minimum of both lateral positions will be used. After all aliquots have
been administered, the LMA will be removed and the baby will be returned to nasal CPAP and
managed by routine protocol. A baby in the LMA group may receive a subsequent LMA treatment
if he/she requires a > 10 percentage-point increase in supplemental oxygen requirement for a
> 30-minute period. Any subsequent dose cannot be given < 6 hours from a previous dose and a
maximum of 3 total LMA doses may be given. No LMA surfactant may be administered under this
protocol after 96 hours of age.
If a baby in either group reaches "failure" criteria, as described below, he/she will
receive standard therapy for severe RDS, which involves endotracheal intubation and
administration of surfactant by endotracheal tube. It is estimated that approximately half
of the patients in the standard group will go on to reach the failure threshold.
"Failure" is defined as follows:
- FiO2 exceeding 65% for 15 minutes to achieve a consistent post-ductal oxygen saturation
of 88-92%, OR
- Apnea of sufficient degree to warrant endotracheal intubation, OR
- Judgment by attending physician that endotracheal intubation is necessary. All subjects
who reach failure criteria will receive endotracheal intubation and conventional
surfactant therapy with Infasurf, unless considered contraindicated by the attending
All patients will have FiO2 adjusted to maintain post-ductal oxygen saturation of 88-92% and
will continue to receive nasal CPAP until either reaching failure criteria, or until FiO2 <
30%. If a subject does not reach failure criteria, nasal CPAP will be weaned to off and the
baby will be place in an oxygen hood until FiO2 = room air. Babies may then be removed from
the hood and returned to supplemental oxygen as clinically indicated.
- Birthweight > 1200 grams
- Chronologic age < 72 hours.
- Diagnosis of RDS by clinical and radiographic criteria.
- Treated with nasal CPAP and supplemental oxygen > 30% and not requiring > 60% FiO2
for longer than 30 minutes to maintain SaO2 88-95%.
- Parental consent.
- Birthweight < 1200 gms.
- Diagnosis other than RDS (e.g., meconium aspiration syndrome).
- Babies who require or have already had endotracheal intubation.
- Babies with congenital anomalies or conditions thought by the attending physician to
contribute to respiratory symptoms and/or to restrict adequate spontaneous breathing
(e.g., congenital heart disease, obtundation from maternal drugs, certain airway
malformations, diaphragmatic hernia).