TY - JOUR
T1 - Open lung ventilation preserves the response to delayed surfactant treatment in surfactant-deficient newborn piglets
AU - Van Veenendaal, Mariëtte B.
AU - Van Kaam, Anton H.
AU - Haitsma, Jack J.
AU - Lutter, René
AU - Lachmann, Burkhard
PY - 2006/11
Y1 - 2006/11
N2 - OBJECTIVE: Delayed surfactant treatment (>2 hrs after birth) is less effective than early treatment in conventionally ventilated preterm infants with respiratory distress syndrome. The objective of this study was to evaluate if this time-dependent efficacy of surfactant treatment is also present during open lung ventilation. DESIGN: Prospective, randomized controlled animal study. SETTING: University-affiliated research laboratory. SUBJECTS: Thirty-eight newborn piglets. INTERVENTIONS: Following repeated whole-lung lavage, animals were randomly allocated to conventional positive pressure ventilation (PPVCON) using a positive end-expiratory pressure (PEEP) of 5 cm H2O and a tidal volume of 7 mL/kg or open lung positive pressure ventilation (PPVOLV). During PPVOLV, collapsed alveoli were actively recruited and thereafter stabilized with sufficient PEEP. Within each ventilation group, animals received surfactant (25 mg/kg) either after 2 hrs (PPVCON-2 and PPVOLV-2) or after 4 hrs (PPVCON-4 and PPVOLV-4) of ventilation. A control group received surfactant immediately after lung lavage. Following surfactant administration, all animals were conventionally ventilated for an additional 2 hrs. MEASUREMENTS AND MAIN RESULTS: Two hours after surfactant treatment, both oxygenation and lung mechanics showed a clear deterioration in the PPVCON-4 group compared with PPVCON-2 and the control group. However, this deterioration of the surfactant response over time was not observed during PPVOLV. Analysis of the bronchoalveolar lavage fluid obtained at the end of the experiment showed that the protein concentration and the conversion of large to small aggregate surfactant was significantly higher in the PPVCON-4 group compared with the PPVCON-2 group while comparable in both PPVOLV groups. In addition, interleukin-8 and myeloperoxidase levels tended to be higher in the PPVCON-4 group compared with the PPVOLV-4 group. CONCLUSIONS: In contrast to conventional ventilation, open lung ventilation preserves the response to delayed surfactant treatment in surfactant-deficient newborn piglets. This sustained response is accompanied by an attenuation of secondary lung injury.
AB - OBJECTIVE: Delayed surfactant treatment (>2 hrs after birth) is less effective than early treatment in conventionally ventilated preterm infants with respiratory distress syndrome. The objective of this study was to evaluate if this time-dependent efficacy of surfactant treatment is also present during open lung ventilation. DESIGN: Prospective, randomized controlled animal study. SETTING: University-affiliated research laboratory. SUBJECTS: Thirty-eight newborn piglets. INTERVENTIONS: Following repeated whole-lung lavage, animals were randomly allocated to conventional positive pressure ventilation (PPVCON) using a positive end-expiratory pressure (PEEP) of 5 cm H2O and a tidal volume of 7 mL/kg or open lung positive pressure ventilation (PPVOLV). During PPVOLV, collapsed alveoli were actively recruited and thereafter stabilized with sufficient PEEP. Within each ventilation group, animals received surfactant (25 mg/kg) either after 2 hrs (PPVCON-2 and PPVOLV-2) or after 4 hrs (PPVCON-4 and PPVOLV-4) of ventilation. A control group received surfactant immediately after lung lavage. Following surfactant administration, all animals were conventionally ventilated for an additional 2 hrs. MEASUREMENTS AND MAIN RESULTS: Two hours after surfactant treatment, both oxygenation and lung mechanics showed a clear deterioration in the PPVCON-4 group compared with PPVCON-2 and the control group. However, this deterioration of the surfactant response over time was not observed during PPVOLV. Analysis of the bronchoalveolar lavage fluid obtained at the end of the experiment showed that the protein concentration and the conversion of large to small aggregate surfactant was significantly higher in the PPVCON-4 group compared with the PPVCON-2 group while comparable in both PPVOLV groups. In addition, interleukin-8 and myeloperoxidase levels tended to be higher in the PPVCON-4 group compared with the PPVOLV-4 group. CONCLUSIONS: In contrast to conventional ventilation, open lung ventilation preserves the response to delayed surfactant treatment in surfactant-deficient newborn piglets. This sustained response is accompanied by an attenuation of secondary lung injury.
KW - Animal study
KW - Cytokines
KW - Intermittent positive-pressure ventilation
KW - Lung mechanics
KW - Respiratory distress syndrome
KW - Surface-active agents
UR - http://www.scopus.com/inward/record.url?scp=33750250872&partnerID=8YFLogxK
U2 - https://doi.org/10.1097/01.CCM.0000243794.09377.96
DO - https://doi.org/10.1097/01.CCM.0000243794.09377.96
M3 - Article
C2 - 17006360
SN - 0090-3493
VL - 34
SP - 2827
EP - 2834
JO - Critical Care Medicine
JF - Critical Care Medicine
IS - 11
ER -