Immediate Effects on Lung Function of Instilled Human Surfactant in Mechanically Ventilated Newborn Infants with IRDS

Preliminary measurements of functional residual capacity (FRC) with the sulphurhexafluoride technique and static pressure volume diagrams were performed in newborn infants with respiratory distress syndrome receiving endotracheal instillation of natural porcine surfactant (Curosurf, 100 or 200 mg/kg). Within the first hour after surfactant treatment there was an increase in FRC and distensibility of the lungs persisting for 24-48 h.

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Lung Mechanics (FRC and Static Pressure-Volume Diagram) after Endotracheal Surfactant Instillation: Preliminary Observations

Svenningsen¹,

Björklund²,

Vilstrup³

et al. 1992

“…[12] 1990 15 min 4 -■ » G jy n increase in FRC Goldsmith ct al. [14] 1991 1 h 7 -» C d y n increase in FRC Svcnningsen et al [15] 1992 24 h 8 Î C " increase in FRC Bhutani et al [9] 1992 1 h 32^ C d y n not measured Phenningcr ct al.…”

Section: Discussionmentioning

confidence: 99%

Pulmonary Effects after Surfactant Treatment in Premature Infants with Severe Respiratory Distress Syndrome

Farstad¹,

Bratlid²

1995

To understand the mechanisms behind the improved oxygenation after intratracheal surfactant instillation, the immediate effects on lung volume and pulmonary mechanics were analyzed. All infants studied were enrolled in multicenter trials in which surfactant therapy was instituted according to a rescue protocol. Infants received either synthetic surfactant (Exosurf) or modified porcine surfactant (Curosurf). Measurements of lung volume and pulmonary mechanics were successfully performed in 12 patients with a birth weight of 1.3 ± (SD) 0.6 (range 0.7-2.7) kg, and a gestational age of 28.3 ± (SD) 1.4 weeks. Functional residual capacity (FRC) and pulmonary mechanics were measured during mechanical ventilation. The FRC increased significantly by 70% (median), from 7.10 ± (SD) 2.8 ml/kg to 11.5 ± 3.3 ml/kg after surfactant instillation. However, a concomitant decrease in specific compliance was also seen. These findings could suggest that this immediate increase in FRC is initially nonuniform. However, since no significant correlation between changes in FRC and improvement in arterial-to-alveolar oxygen tension ratio is seen, other effects of surfactant must also be considered. These could include local and/or systemic changes in hemodynamics, such as decreased shunting as well as various effects on gas diffusion.

“…The decrease in BP may be related to the rapid recniitment of atelectatic areas by surfactant treatment [21,22], possibly leading to a de crease in the pulmonary vascular resistance and, consequently, to an increase in left-toright shunting through the ductus arteriosus [11], Also a decrease in peripheral vascular resistance as described by Skov et al [10] and by Cowan et al [9] may lead to a transient drop in BP. CBFVs may also be subject to variations in PCO2.…”

Section: Resultsmentioning

confidence: 99%

Surfactant Bolus Instillation: Effects of Different Doses on Blood Pressure and Cerebral Blood Flow Velocities

Reisslein¹,

Segerer²,

Kiessling³

et al. 1994

Fifteen preterm infants suffering from respiratory distress syndrome were randomly allocated to receive either high-dose (200 mg/kg) or low-dose (100 mg/kg) surfactant treatment. Retreatments were done with the low dose. Blood pressure, blood gases and cerebral blood flow velocities were determined before and after 24 bolus instillations. With the high dose mean blood pressure and mean cerebral blood flow velocity dropped significantly. With the low dose only mean cerebral blood flow velocity decreased; the course was unrelated to blood pressure or PCO₂ fluctuations. The mechanisms leading to the observed circulatory changes after surfactant instillation remain unclear.