Effects of surfactant on lung injury induced by hyperoxia and mechanical ventilation in rabbits

Abstract

We evaluated the effects of exogenous surfactant on lung injury caused by 100% oxygen and mechanical ventilation in rabbits. Surfactant-treated rabbits (n = 9) were ventilated with 100% oxygen for 36 hours and bovine surfactant was given via the trachea 12 hours after the start of mechanical ventilation. Saline-treated (n = 9) rabbits were treated identically, except that they received saline without surfactant. There were no significant changes in hemodynamics, lung mechanics, or arterial oxygen tension during artificial ventilation. Albumin concentration in the bronchoalveolar lavage fluid (BALF) of saline-treated rabbits was slightly higher than those in surfactant-treated rabbits and significantly higher than in non-treated rabbits. C3a concentration in BALF was significantly higher in saline-treated rabbits than in surfactant-treated and non-treated rabbits. In addition, the wet-to-dry lung weight ratio was significantly lower in surfactant-treated rabbits than in saline-treated rabbits (5.06 +/- 0.10 vs. 5.67 +/- 0.14, P < 0.05). Light microscopy revealed hyaline membrane formation in saline-treated rabbits, but fewer changes were observed in surfactant-treated rabbits. Electron microscopy revealed extensive endothelial cell destruction in saline-treated rabbits, while such changes except endothelial cell swelling were not observed in surfactant-treated rabbits. We conclude that exogenous surfactant attenuated lung injury caused by oxygen exposure and ventilation.

Lidocaine attenuates hyperoxic lung injury in rabbits

“…Increased albumin levels in BALF without impaired lung function have been shown in humans breathing 100% oxygen (20). Our previous findings have also indicated that pathological lung damage never correlates with deterioration of oxygenation in hyperoxic lung injury (21,22). Severe pulmonary impairment has been shown to be unusual despite the presence of acute pathologic findings, including interstitial fibrosis (23).…”

“…Monkeys and baboons are more resistant than these small animals but more susceptible than chickens. We have used rabbits as a model of hyperoxic lung injury (4, 21,22). The animals survive 3 days of exposure to approximately 100% oxygen.…”

Novel transcript profiling of diffuse alveolar damage induced by hyperoxia exposure in mice: normalization by glyceraldehyde 3-phosphate dehydrogenase

“…Apart from hyperoxia exposure and mechanical ventilation [4], DAD could be caused by various etiology, including paraquat poisoning [5,6], idiopathic causes [7,8], and nonthoracic trauma [9].…”

Porcine versus bovine surfactant therapy for RDS in preterm neonates: pragmatic meta-analysis and review of physiopathological plausibility of the effects on extra-pulmonary outcomes

“…These results are only partially similar to those of the earlier Cochrane meta-analysis [8] but they are also stronger. In fact, compared to the previous work we: 1) included five more trials (accounting for ≈600 neonates); 2) used a trials aggregation based on the current best knowledge, that is, on the clinical equivalence of bovine surfactant [8]; 3) analyzed the effect of possible confounders, such as [46][47][48][49] ↓ Prostaglandins synthesis [50,51] ↓ PVR [46,47,[52][53][54] IVH ↓ PaCO2 and CBF [55][56][57] ↓ PDA [53,54] Better peripheral perfusion [34,42] Improved cerebral oxygenation [58] ROP ↓ oxygen and ROS exposure [49,[59][60][61][62][63] NEC ↓ oxygen and ROS exposure [49,64] Better peripheral perfusion [34,42] Earlier progression to full enteral feeding [65][66][67][68] More details in the text. Abbreviations: ROS Reactive oxygen species, PVR Pulmonary vascular resistances, CBF Cerebral blood flow, PaCO2 Arterial partial pressure of CO2, PDA Patent ductus arteriosus, IVH Intraventricular hemorrhage, ROP Retinopathy of prematurity, NEC Necrotizing enterocolitis antenatal steroids or gestational age, and finally, 4) reviewed the possible physiopathological mechanisms linking surfactant replacement and extra-pulmonary outcomes.…”