Introduction: There is a growing body of evidence that surfactant delivery via a thin catheter
(minimally invasive surfactant therapy, MIST) is a safe and effective method in reducing
the need for subsequent intubation and improves short-term respiratory outcome in
spontaneously breathing infants with respiratory distress syndrome (RDS). Preterm
infants are known to be vulnerable to oxidative damage because of inadequate antioxidant
capacity. The imbalance between oxidative stress and antioxidant defense systems is
suggested to predispose the immature lungs to the development of RDS. In this study,
we compared the effects of poractant alfa and beractant given with minimally invasive
method on total oxidative stress (TOS) and total antioxidant capacity (TAC) in infants
with RDS.
Materials and Methods: Infants diagnosed with RDS and treated with MIST were included. One group received
an initial dose of poractant alfa (Curosurf, Chiesi Pharmaceuticals, Parma, Italy,
200 mg/kg); the other group received beractant (Survanta, Ross Laboratories, Columbus,
OH, 100 mg/kg) via 5F nasogastric tube. Patients who required FiO2 ≥40 were given additional doses (each of 100 mg/kg). Blood samples were drawn before
and 24 hours after surfactant treatment to measure TAC and TOS. TAC and TOS levels
were analyzed by Erel’s method. Oxidative stress index (OSI) was calculated with TOS
to TAC ratio.
Results: Forty infants were enrolled, n = 12 in the poractant alfa group, and n = 28 in the beractant group. Clinical and laboratory features of infants are depicted
in [Table 1]. There were no differences between the two groups in terms of pre- and postsurfactant
TAC, TOS, and OSI levels. TAC levels showed a nonsignificant trend toward increase
following surfactant treatment in each group, Postsurfactant TOS levels were lower
than presurfactant measurements in both beractant and poractant groups; 27.9 (2.1–182)
versus 11.7 (1.7–74.8) μmol H2O2/L, p = 0.034 and 31.5 (3.9–152) versus 8.3 (2.5–32) μmol H2O2/L, p = 0.006, respectively. Postsurfactant OSI was significantly lower in poractant alfa
group.
Conclusion: Both natural surfactant preparations appear equally effective in treatment of RDS
with the prominent reduction of TOS levels.
Keywords: respiratory distress syndrome, surfactant, minimally invasive surfactant therapy,
total oxidative stress, total antioxidant capacity
Table 1 Clinical and laboratory features of infants
|
Beractant n = 28
|
Poractant n = 12
|
p-Value
|
|
Gestational age, wk
|
31 (28–39)
|
30 (24–35)
|
0.055
|
|
Birth weight, g
|
1,647 (800–3,000)
|
1,215 (695–2,270)
|
0.01
|
|
Cesarean delivery, n (%)
|
26 (93)
|
8 (66)
|
0.125
|
|
Oligohydramnios, n (%)
|
3 (10.7)
|
1 (8.5)
|
0.88
|
|
Apgar 1 (min–max)
|
5 (2–8)
|
4 (3–7)
|
0.676
|
|
Apgar 5 (min–max)
|
8 (6–9)
|
7 (7–8)
|
0.048
|
|
Male/Female
|
14/14
|
7/5
|
0.736
|
|
Antenatal steroid, n (%)
|
10 (35.7)
|
4 (33.3)
|
0.588
|
|
Cord blood pH (min–max)
|
7.31 (7.12–7.41)
|
7.29 (7.17–7.42)
|
0.942
|
|
Invasive ventilation
|
|
SIMV, n (%)
|
19 (68)
|
5 (41.6)
|
0.072
|
|
SIMV, d
|
2 (1–4)
|
2 (1–30)
|
0.730
|
|
Noninvasive ventilation
|
|
CPAP, n (%)
|
25 (89.3)
|
12 (100)
|
0.258
|
|
CPAP, d
|
3 (1–15)
|
1.5 (1–3)
|
0.277
|
|
NIMV, n (%)
|
24 (85.7)
|
9 (75)
|
0.762
|
|
NIMV, days
|
2 (1–11)
|
4.5 (1–16)
|
0.728
|
|
BPD, n (%)
|
3 (10.7)
|
3 (25)
|
0.323
|
|
Duration of hospitalization, d (min–max)
|
29 (12–70)
|
39 (8–60)
|
0.189
|
|
Mortality, n (%)
|
0
|
1 (8.5)
|
0.300
|
|
TAC 1, mmol Trolox equiv./L (min–max)
|
1.5 (0.6–13)
|
1.5 (0.5–2.6)
|
0.703
|
|
TAC 2, mmol Trolox equiv./L (min–max)
|
1.85 (0.2–2.9)
|
2.1 (0.6–2.8)
|
0.346
|
|
TOS 1, μmol H2O2/L (min–max)
|
27.9 (2.1–182)
|
31.5 (3.9–152)
|
0.603
|
|
TOS 2, μmol H2O2/L (min–max)
|
11.7 (1.7–74.8)
|
8.3 (2.5–32)
|
0.293
|
|
OSI 1, arbitrary unit (min–max)
|
20.2 (0.4–160)
|
30.2 (1.8–141)
|
0.212
|
|
OSI 2, arbitrary unit (min–max)
|
6.4 (0.68–374)
|
4.1 (1.2–53.3)
|
0.362
|
Abbreviations; BPD, bronchopulmonary dysplasia; CPAP, continuous positive airway pressure;
HFO, high-frequency oscillation; IVH, intraventricular hemorrhage; NEC, necrotizing
enterocolitis; NIMV, noninvasive mechanical ventilation; OSI, oxidative stress index;
PDA, patent ductus arteriosus; PPROM, premature rupture of membranes; PVL, periventricular
leucomalacia; RDS, respiratory distress syndrome; ROP, retinopathy of prematurity;
SIMV, synchronized intermittent mandatory ventilation; TAC, total antioxidant capacity;
TOS, total oxidant status.