Effects of Poractant Alfa and Beractant on Total Oxidative Stress and Total Antioxidant Capacity of Infants with Respiratory Distress Syndrome

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.