Aerosolized perfluorocarbon improves gas exchange and pulmonary mechanics in preterm lambs with severe respiratory distress syndrome

Abstract

Background: aerosolized perfluorocarbon (PFc) has been proposed as an alternative method of PFc administration; however, the efficacy of aerosolized PFc in a preterm animal model has not yet been demonstrated. Methods: Twelve preterm lambs were randomized to two groups: a perfluorodecalin (PFD) aerosol group (n = 6) receiving 10 ml/kg/h of PFD delivered by an intratracheal inhalation catheter followed by 4 h of mechanical ventilation (MV) or the control group, in which animals (n = 6) were managed for 6 h with MV. Gas exchange, pulmonary mechanics, cardiovascular parameters, and cerebral blood flow (cBF) were measured. results: Both groups developed hypoxia, hypercarbia, and acidosis at baseline. aerosolized PFD improved oxygenation (P < 0.0001) and pulmonary mechanics (P < 0.0001) and changed carbon dioxide values to normal physiological levels, unlike the treatment given to the controls (P < 0.0003). The time course of mean arterial blood pressure and cBF were significantly affected by PFD aerosolization, especially during the first hour of life. cBF gradually decreased during the first hour in the PFD aerosol group and remained stable until the end of the follow-up, whereas cBF remained higher in the control group (P < 0.0028). conclusion: aerosolized PFD improves pulmonary function in preterm lambs and should be further investigated as an alternative mode of PFc administration.

In Vitro Surfactant and Perfluorocarbon Aerosol Deposition in a Neonatal Physical Model of the Upper Conducting Airways

“…For instance, a standard porcine surfactant dose (200 mg/kg) for a 1,500 g infant could be delivered in just 10 minutes in contrast to the longer aerosolization times previously reported in the literature [7], [15], [28]. In the case of PFCs, recognizing that the ideal dose for aerosol delivery may vary depending on the PFC type [20], [23], [29], a dose of 10 ml/kg could be delivered to the same infant in just 10 minutes.…”

“…Aerosol delivery of surfactant and PFC has been proposed as an alternative to their intratracheal instillation for the treatment of various pulmonary diseases, including neonatal RDS [9], [12], [20], [23], [33]. The main goal of aerosol therapy with surfactant and PFC for the treatment of this syndrome would be to administer these compounds during non-invasive ventilation with minimal airway manipulation.…”

“…In addition to surfactant, we used two different types of PFC: perfluorodecalin (PFD; C 10 F 18 , F2 Chemicals Ltd., Lancashire, UK; density at 25°C = 1.95 g/ml; kinematic viscosity  = 2.7 cSt; vapor pressure at 37°C = 14 mmHg; surface tension  = 15 dyne/cm) and FC-75 (C 8 F 16 O, Fluorinert, 3 M, Neuss, Germany; density at 25°C = 1.78 g/ml; kinematic viscosity  = 0.81 cSt; vapor pressure at 37°C = 63 mmHg; surface tension  = 15 dyne/cm). These PFC species have been previously tested in several experimental studies [22], [23]. Also, distilled water (H 2 Od, B. Braun, Melsungen, Germany; density  = 1 g/ml; kinematic viscosity  = 1.003 cSt; surface tension  = 73 dyne/cm) was used to simulate the aerosolization of aqueous medications.…”

Acute and sustained effects of aerosolized vs. bolus surfactant therapy in premature lambs with respiratory distress syndrome

“…This comparative study was carried out using 14 premature Latxa lambs delivered at 133 d of gestation (term = 145 d), it having been shown that there is severe pulmonary SF deficiency in lambs of this breed at this gestational age (29,30). Mean body weight of the lambs at birth was 3.1 ± 0.4 kg.…”

“…These animals also received 200 mg/kg of poractant alfa continuously aerosolized (during inspiration) over a period of 20 min (n = 7), delivered intratracheally by means of inhalation catheters (AeroProbe; Trudell Medical, London, Ontario, Canada) connected to a pneumatic compressor (LABneb*CCS; Trudell Medical) (30). This aerosol system can deliver up to 0.4 ml of SF per min during mechanical ventilation, with 80% of the particles having a diameter of <5 µm (21,31).…”