Surfactant and partial liquid ventilation via conventional and high-frequency techniques in an animal model of respiratory distress syndrome.
OBJECTIVE: To compare the physiologic and pathologic effects of conventional ventilation (CV) and high-frequency ventilation (HFV) during partial liquid ventilation (PLV) with perflubron after surfactant treatment with the results of HFV plus surfactant in an animal lung-injury model created by saline lavage. We also studied the dose effects of perflubron during HFV. DESIGN: Randomized experimental study. SETTING: Research animal laboratory. SUBJECTS: A total of 32 newborn piglets. INTERVENTIONS: After lung injury was induced, the animals were randomized to one of four groups: a) CV + surfactant + perflubron to functional residual capacity (FRC); b) HFV + surfactant + perflubron to FRC; c) HFV + surfactant + 10 mL/kg perflubron; and d) HFV + surfactant. All then received intratracheal surfactant. After 30 mins, perflubron was administered to the PLV groups. The animals underwent ventilation for 20 hrs. MEASUREMENTS AND MAIN RESULTS: Arterial blood gases and hemodynamic variables were continuously monitored. Pulmonary histologic and morphometric analyses were performed after death or euthanasia at 20 hrs. All animals had sustained improvements in arterial/alveolar oxygen ratios, and no differences were observed among groups. All HFV groups required higher mean airway pressures to maintain oxygenation (p <.05). Hemodynamics did not differ among groups. Pathologic analysis demonstrated decreased lung injury in both cranial-dorsal (nondependent) and caudal-ventral (dependent) lobes of all animals treated with PLV when compared with those treated with HFV + surfactant (p <.05). CONCLUSIONS: After surfactant treatment, physiologic support over 20 hrs was similar during HFV with or without perflubron and CV with perflubron. All PLV modalities improved lung pathologic factors uniformly to a greater degree than did HFV + surfactant. A lower treatment volume of perflubron during HFV produced physiologic and pathologic results similar to those produced by perflubron with respect to FRC during either CV or HFV.
Bendel-Stenzel
Ellen M.
EM
Infant Pulmonary Research Center, Children's Hospital of St. Paul, St. Paul, Minnesota (Drs. Manaligod, Bendel-Stenzel, Smith, Simonton, Connett, and Mammel; Mr. Bing; and Ms. Meyers); the departments of Pediatrics (Drs. Manaligod, Bendel-Stenzel, and Mammel) and Biostatistics (Dr. Connett), University of Minnesota, Minneapolis, Minnesota; and Alliance Pharmaceutical Corporation, San Diego, California (Dr. Smith).
Smith
Kendra M.
KM
Simonton
Susan C.
SC
Bing
Dennis R.
DR
Meyers
Pat A.
PA
Connett
John E.
JE
Mammel
Mark C.
MC