OBJECTIVE: Partial liquid ventilation (PLV) has been shown to exhibit anti-inflammatory properties during non-infectious models of acute lung injury. The aim of this experimental study was to assess the effects of PLV on bacterial clearance during Pseudomonas aeruginosa-induced pneumonia in rats. DESIGN: The rats were assigned to four groups 4 h after bacterial challenge according to the kind of mechanical ventilation [gas ventilation (GV) or PLV, 6 ml/kg perflubron plus 2 ml/kg per h] and to the level of PEEP used (3 or 8 cm of water). Physiologic measures were recorded during anesthesia (arterial blood gases, airway and blood pressures) for 4 subsequent hours until sacrifice. RESULTS: No improvement of oxygenation was demonstrated in any group. The bacterial counts were higher in PLV-PEEP 8 rats compared to GV-PEEP 8 rats: median, 1.7.10(4) cfu (25th-75th percentiles, 1.2.10(4)-1.8.10(4)) versus 1.1.10(4) (8.7.10(3)-1.3.10(4))/ml of BAL fluid and 4.0.10(6) cfu (2.0.10(6)-5.5.10(6)) versus 1.7.10(6) cfu (9.7.10(5)-3.2.10(6))/ml of lung homogenate, respectively ( P<0.05, n=8/10 surviving rats per group). PEEP 8 was associated with a significant decrease in neutrophil recruitment in BAL fluid compared to PEEP 3 in both GV and PLV groups. Additional in vitro experiments demonstrated that perflubron induced a decrease in phagocytosis of P. aeruginosa by alveolar neutrophils. CONCLUSIONS: These results demonstrate that PLV is associated with an impaired bacterial clearance during early pneumonia in rats, which could have been favored by decreased bacterial phagocytosis by neutrophils.
OBJECTIVE: Partial liquid ventilation (PLV) has been shown to exhibit anti-inflammatory properties during non-infectious models of acute lung injury. The aim of this experimental study was to assess the effects of PLV on bacterial clearance during Pseudomonas aeruginosa-induced pneumonia in rats. DESIGN: The rats were assigned to four groups 4 h after bacterial challenge according to the kind of mechanical ventilation [gas ventilation (GV) or PLV, 6 ml/kg perflubron plus 2 ml/kg per h] and to the level of PEEP used (3 or 8 cm of water). Physiologic measures were recorded during anesthesia (arterial blood gases, airway and blood pressures) for 4 subsequent hours until sacrifice. RESULTS: No improvement of oxygenation was demonstrated in any group. The bacterial counts were higher in PLV-PEEP 8 rats compared to GV-PEEP 8 rats: median, 1.7.10(4) cfu (25th-75th percentiles, 1.2.10(4)-1.8.10(4)) versus 1.1.10(4) (8.7.10(3)-1.3.10(4))/ml of BAL fluid and 4.0.10(6) cfu (2.0.10(6)-5.5.10(6)) versus 1.7.10(6) cfu (9.7.10(5)-3.2.10(6))/ml of lung homogenate, respectively ( P<0.05, n=8/10 surviving rats per group). PEEP 8 was associated with a significant decrease in neutrophil recruitment in BAL fluid compared to PEEP 3 in both GV and PLV groups. Additional in vitro experiments demonstrated that perflubron induced a decrease in phagocytosis of P. aeruginosa by alveolar neutrophils. CONCLUSIONS: These results demonstrate that PLV is associated with an impaired bacterial clearance during early pneumonia in rats, which could have been favored by decreased bacterial phagocytosis by neutrophils.
Authors: François Stephan; Kun Yang; Jacques Tankovic; Claude-James Soussy; Gilles Dhonneur; Philippe Duvaldestin; Laurent Brochard; Christian Brun-Buisson; Alain Harf; Christophe Delclaux Journal: Crit Care Med Date: 2002-02 Impact factor: 7.598
Authors: V M Ranieri; P M Suter; C Tortorella; R De Tullio; J M Dayer; A Brienza; F Bruno; A S Slutsky Journal: JAMA Date: 1999-07-07 Impact factor: 56.272
Authors: S Rezaiguia; C Garat; C Delclaux; M Meignan; J Fleury; P Legrand; M A Matthay; C Jayr Journal: J Clin Invest Date: 1997-01-15 Impact factor: 14.808