Results:
Out of the total 6007 admissions, 434 (7%) neonates had meconium
stained liquor and respiratory distress at birth. The respiratory
distress settled within 24 hours in 40 neonates. In the remaining 384
neonates, 347 were discharged home and were enrolled for the study. A
total of 10 neonates died, 24 were categorised as Leave against medical
advice (LAMA) and 3 were repatriated to the referral hospitals for the
continuation of care and outcome data were not available. The mortality
including the neonates sent LAMA with grave outcomes was 23 (5.9%). The
flow of the patients is summarized in figure 1.
About 35% of neonates required resuscitation at birth. At admission,
163 (47%) neonates had significant distress, evidenced by Downes score
≥4. 184 (53%) were stabilized on CPAP as primary respiratory support.
The neonates in the cohort had associated morbidities of HIE stage 2 or
3 in 67 (19%), surfactant requirement 94 (27%), PPHN in 80 (23%). The
median length of hospital stay (IQR) was 10 (7-14) days. The baseline
characteristics of enrolled neonates are outlined in table 1.
Amongst 347 neonates, 103 (29%) were discharged before 7 days and
remaining 244 (71%) had prolonged stay. On univariate comparison of
short stay versus long stay (table 2), Positive pressure ventilation
(PPV) at birth (27% vs 38%, p=0.05), intubation at birth (2% vs 19%,
p<0.001), HIE stage 2 or 3 (2% vs 27%, p<0.001),
Fio2 at 1hr>30% (45% vs 87%, p<0.001), Downe’s
score at admission ≥4 (64% vs 90%, p<0.001), primary support
beyond O2 (CPAP or MV) (42% vs 83%, p<0.001), CPAP as
primary support after admission (36% vs 60%, p<0.001),
invasive mechanical ventilation (6% vs 23%, p<0.001),
surfactant requirement (1% vs 38%, p<0.001), moderate-severe
PPHN (3% vs 31%, p<0.001) were statistically significant
factors seen in the prolong stay group. Although CPAP as primary support
was seen as a statistically significant risk factor in the prolonged
stay, CPAP initiation was delayed by a mean difference of 21 hrs (-32 to
-10) in the prolonged stay group compared to short stay.
On multivariate analysis, 4 parameters, namely primary support beyond
oxygen, FiO2 more than 30% one hour post admission, presence of
moderate-severe PPHN, HIE stage 2 or 3, were found to be independent
predictors of prolonged stay in hospital (Table 3). These 4 variables
were used to devise a scoring system predictive of prolonged stay in
MAS. The beta coefficients obtained from the logistic regression were
used to calculate the weights of these parameters. The final weighted
score is as follows: 9 (Primary support beyond oxygen) + 15 (FiO2 more
than 30% 1hour after admission) + 20 (moderate-severe PPHN) + 29 (HIE
stage 2 or 3), with each variable being assigned a value as ‘1’ if
present and ‘0’ if absent. The ROC curve was plotted to evaluate the
predictive ability of the weighted score. The Area under curve (AUC) was
82% (95% CI 78-87%), p<0.001 and thus had excellent model
discriminatory power. Based on the distribution of the neonates in both
the groups for the weighted score and ROC curve analysis (Table 3)
(figure 2), the optimal cutoff for prolonged stay was determined. The
optimal cutoff was \(\geq\) 21 had sensitivity, specificity, positive
predictive value and negative predictive value of 83%, 68%, 86% and
62%, respectively. The positive and negative likelihood ratios were 2.6
and 0.25, respectively.