Lung aeration during ventilation after recruitment guided by tidal elimination of carbon dioxide and dynamic compliance was better than after end-tidal carbon dioxide targeted ventilation: A computed tomography study in surfactant-depleted piglets
2011 (English)In: Pediatric Critical Care Medicine, ISSN 1529-7535, E-ISSN 1947-3893, Vol. 12, no 6, E362-E368 p.Article in journal (Refereed) Published
Objective: To test the hypothesis that tidal elimination of carbon dioxide and dynamic compliance guided lung recruitment and positive end-expiratory pressure titration in surfactant-depleted piglets result in improved aeration (repeated computed tomography scans) and reduced ventilation pressures compared to those of a control group with conventional end-tidal carbon dioxide targeted ventilation.
Design: Prospective animal investigation.
Setting: Clinical physiology research laboratory.
Subjects: Seventeen saline-lavaged piglets.
Interventions: The piglets were initially ventilated at an end-inspiratory pressure of 20 cm H(2)O, a positive end-expiratory pressure of 5 cm H(2)O, and a tidal volume of 10 mL kg(-1) for an end-tidal carbon dioxide target of 30-45 torr followed by 5 mins of ventilation without positive end-expiratory pressure. After this, the control group was ventilated for the same end-tidal carbon dioxide target during the study period. In the recruitment group, the protocol started with an increase of the positive end-expiratory pressure to 15 cm H(2)O. The end-inspiratory pressure was then increased in steps of 3 cm H(2)O to a tidal elimination of carbon dioxide peak/plateau in one recruitment group and further increased in two steps in a second recruitment group. A downward positive end-expiratory pressure titration was followed by continuous dynamic compliance monitoring. The "open lung positive end-expiratory pressure" was set 2 cm H(2)O above the positive end-expiratory pressure at the first dynamic compliance decline and used for a final "open lung ventilation" period.
Measurements and Main Results: The recruitment groups showed better aeration, lower ventilatory pressure amplitude, and better dynamic compliance than the control group at the end of the study. Recruitment using airway pressures above the tidal elimination of carbon dioxide peak/plateau did not improve aeration. Using end-tidal carbon dioxide targeted ventilation in the control group restored aeration after the ventilation without positive end-expiratory pressure, but no recruitment or improvement of dynamic compliance was measured.
Conclusions: Aeration was significantly better after recruitment and positive end-expiratory pressure titration than in a control group managed by "conventional" end-tidal carbon dioxide targeted ventilation. An increase of the end-inspiratory pressure above the tidal elimination of carbon dioxide peak/plateau did not result in an increased amount of normally aerated lung. A recruitment maneuver resulted in a lower ventilatory amplitude for achieving a target tidal volume and better dynamic compliance at the end of the study period compared to those of the control group.
Place, publisher, year, edition, pages
2011. Vol. 12, no 6, E362-E368 p.
lung recruitment, tidal elimination of carbon dioxide, positive end-expiratory pressure, dynamic compliance, computed tomography, pediatric, open lung ventilation
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:uu:diva-162694DOI: 10.1097/PCC.0b013e31820aba6eISI: 000296767900025OAI: oai:DiVA.org:uu-162694DiVA: diva2:462433