Material and methods
This retrospective study was conducted involving 6 tertiary care NICU of
South India over a period from August 2019 to December 2022. Both inborn
and outborn preterm neonates born between 24- 34 weeks of gestation
having RDS and requiring rescue surfactant were enrolled. Exclusion
criteria included babies with antenatally or postnatally suspected or
diagnosed structural lung disease, major congenital malformations and
where death or discharge (against medical advice) or referred to other
NICU occurred within 24 hours of life. The Institutional ethics
committee approved the study at all centres.
Of the 6 tertiary centres that participated, one was a trust hospital,
while the other 5 were private sector hospitals. All the centres catered
to both inborn and outborn neonates. All the centres started delivery
room CPAP with settings of 5 PEEP and 30% FiO2 using a T piece
resuscitator in spontaneously breathing infants. Surfactant was
administered predominantly using INSURE technique when the baby
continued to have respiratory distress on settings of ≥ 6 cm PEEP and
FiO2 >30%.1 All units either used
porcine surfactant (Curosurf, Chiesi, USA Inc) at 200 mg/kg or bovine
(Neosurf, Cipla/Survanta, Abbott) at 100 mg/kg. The choice of surfactant
was individual clinician based, however there was inclination towards
usage of porcine for extreme preterm owing to smaller volume of the
dose. Redosing was considered when the baby continued to have
respiratory distress needing ≥ 6 cm PEEP and FiO2 >30%,
after 12 hours of first dose. Nasal mask was used as a nasal interface
in 5 centres and Ram’s cannula was used in one centre. All centres had
nurse:patient ratio of 1:2. Overall the protocols of managing RDS were
similar across centres.
The data were identified from the unit specific registers/database. Case
records of NICU admissions across the hospitals in the collaboration
were retrieved. Data retrieved included demographic, antenatal,
perinatal parameters related to RDS and neonatal morbidities and
mortality. A standardised data collection proforma was used across all
units. Data was entered into a common database with coding of the
centres. Chronic lung disease (CLD) was defined as need for supplemental
oxygen at 36 weeks i.e., moderate to severe CLD as per the NICHD
criteria6.
The primary outcome measure studied was combined outcome of Mortality or
Chronic Lung Disease (CLD). The secondary outcome measures which were
studied are proportion of babies requiring redosing of surfactant, Air
leaks, invasive ventilation, ROP requiring LASER, PDA requiring
treatment, Intraventricular hemorrhage (IVH) (>Grade 3 or
4), Necrotizing enterocolitis (NEC) (>Stage 2B) and
duration of hospital stay.