INTENSIVE CARE

The Benefits of a Laryngeal Mask Airway
Over Endotracheal Intubation for Surfactant
Delivery
Chris Campbell
When it comes to any type of treatment—every step should be
taken to ensure the cure doesn’t do more harm than good. Some
treatments are effective in achieving the goal intended, but are so
hard on the human body that they can cause long-term damage.
Case in point—surfactant therapy, an effective treatment to
increase the ability of the lung to inflate. But the way surfactant
is delivered can have a negative impact on a patient, especially
when it comes to the most fragile patients a hospital can treat—
neonates. According to a study by the Department of Pediatrics
at the Albany Medical College, the risks of “chronic lung disease”
are increased for neonates if mechanical ventilation is required
during the administration of surfactant due to “protracted
respiratory depression.”
So the AMC team of Pinheiro et al set out to study two methods
of delivering surfactant—the standard approach of intubationsurfactant-rapid
extubation, or INSURE, via endotracheal tube
(ETT) versus the laryngeal mask airway (LMA).
The goal was to “evaluate whether surfactant therapy delivered
through an LMA in moderately preterm neonates with mild-tomoderate
respiratory distress syndrome (RDS) can effectively
replace an INSURE approach while decreasing the need for
subsequent mechanical ventilation.”
Surfactant Delivery
While surfactant improves oxygenation and reduces the need
for mechanical ventilation, the AMC study describes the tricky
situation in delivering the therapy to neonates: “Tracheal
intubation with positive pressure ventilation (PPV) is the
approved method of surfactant delivery…However, intubation
induces pain and physiological instability in neonates, leading
to hypoxemia and bradycardia while increasing systemic and
intracranial pressures. 4-6 Premedication to minimize pain and
stress of neonatal intubation is recommended by the American
Academy of Pediatrics and Canadian Paediatric Society, 7,8 as
available evidence suggests that it may increase procedural
effectiveness and safety relative to unmedicated intubations. 9-12
Premedication with morphine and atropine was used routinely in
the Albany Medical Center neonatal intensive-care unit (NICU)
for elective intubations, including those performed for rescue
surfactant. However, protracted respiratory depression may
necessitate mechanical ventilation, which increases the risk of
chronic lung disease. 1,2 Indeed, administering surfactant while
minimizing exposure to invasive ventilation is the rationale
Chris Campbell is the Senior Editor of Neonatal Intensive Care.
underlying the INSURE (intubation-surfactant-rapid extubation)
approach to surfactant therapy.” 13,14
However, the authors added that the INSURE strategy can
“reduce the need for intubation and mechanical ventilation, 13 but
it still requires laryngoscopy and transient tracheal intubation,
using either an ETT, 13,30,31 a feeding catheter 32 or a vascular
catheter.” 33,34
The authors warned that the use of an ETT “may have immediate
and persistent adverse effects.” The LMA approach is a
“supraglottic, minimally invasive device that can support shortterm
ventilation in adults, children or neonates, 15 avoiding some
undesirable effects of endotracheal intubation. LMAs are easily
inserted with minimal training, resulting in less misplacement
and failure of ventilation than intubation. 16 The LMA is an
effective airway for neonatal resuscitation, 3 but it has also been
used to administer surfactant. Recent studies including casereports
and pilot trials on preterm neonates 15,17-20 and data from
a piglet model of RDS 21 suggest that the LMA might be useful
for minimally invasive surfactant administration, although its
effectiveness relative to tracheal intubation remains unknown.” 22
Designing The Study
The AMC team put these two approaches to the test between
2010 and 2012 at the Albany Medical Center NICU. Over 32
months of enrollment, 146 patients were assessed for eligibility,
and 61 were randomized. The study authors noted that this is
the “first to directly compare surfactant delivery via an LMA to
traditional administration through an ETT, demonstrating that
both methods produce similar acute physiologic improvement.”
The study is also unique “addressing the practical question of
whether surfactant delivered via LMA produces similar effects to
a contemporary INSURE strategy on both FiO2 and short-term
clinical outcomes.”
According to the study authors, “moderately preterm infants
diagnosed with RDS, receiving nasal continuous positive
airway pressure with FiO2 0.30 to 0.60, were randomized to
two groups at age 3 to 48 h. Those in the ETT group were
intubated following premedication with atropine and morphine,
whereas the LMA group received only atropine. Both groups
received calfactant before a planned reinstitution of nasal
continuous positive airway pressure, and had equivalent prespecified
criteria for subsequent mechanical ventilation and
surfactant retreatment. The primary outcome was failure of
24 neonatal INTENSIVE CARE Vol. 29 No. 4 • Fall 2016