Abstracts and Programme: EUROANAESTHESIA 2011: The European Anaesthesiology Congress: Best Abstracts - Runner-up Session 1
Background and Goal of Study: Intravascular volume replacement may be necessary during acute lung injury (ALI). We compared the effects of Ringer's acetate (RA), gelafundin (GEL), and hydroxyethyl starch (HES), on lung function and damage in experimental ALI.
Materials and Methods: ALI was induced by lung saline lavage followed by ventilator induced lung injury in 30 anesthetized pigs (28.4-42.8 kg). Protective ventilation (VT=6ml/kg, PEEP=16cmH2O) was initiated and »25% of the estimated blood volume was drawn. The intravascular volume was partially replaced with either RA, GEL or HES (n=10/group, random assignment) to achieve »80% of the intrathoracic blood volume (ITBV) measured before blood drainage. Gas exchange, hemodynamic variables and lung mechanics were measured during 4 hours of protective mechanical ventilation. Lung histological damage, pro-inflammatory lung response and wet-to-dry (W/D) ratio were assessed post-mortem.
Results and Discussion: The two-hit model resulted in severe hypoxemia (PaO2/FiO2 = 61 ± 23 mmHg). Following blood drainage, the amount of fluid needed to achieve the target ITBV was higher in RA (2250±764 ml) than GEL (704±159 ml) and HES (837±82 ml) groups (p< 0.05). Gas exchange and hemodynamic variables did not differ among groups but lung elastance was lower with HES and GEL than RA. The diffuse alveolar damage was lower in ventral areas with GEL (p < 0.05) and showed a trend toward decreased values with HES compared to RA. In ventral areas, the colloids reduced the gene expression of IL-1b compared to the crystalloid. In dorsal areas, the gene expression of IL-8 was reduced with GEL (p< 0.05) and showed a trend toward lower levels with HES, compared to RA. Both colloids resulted in lower W/D ratios compared to the crystalloid (GEL: 6.5±0.5, HES: 6.5±0.7, RA: 7.9±1.0, respectively; p < 0.05).
Conclusion(s): In this non-septic model of ALI, intravascular volume replacement with Ringer's acetate worsens lung elastance, histological damage, the pro-inflammatory lung response and edema compared to gelatin and hydroxyethyl starch solutions.