Am. J. Respir. Crit. Care Med.,
Volume 162, Number 6, December 2000, 2278-2286
Halothane Reduces the Early Lipopolysaccharide-induced Lung Inflammation in Mechanically
Ventilated Rats
OLIVIER
GIRAUD,
PIERRE-FRANÇOIS
SEINCE,
CORINNE
ROLLAND,
VÉRONIQUE
LEÇON-MALAS,
JEAN-MARIE
DESMONTS,
MICHEL
AUBIER,
and
MONIQUE
DEHOUX
Unité INSERM 408, Faculté de Médecine Xavier Bichat, Département d'Anesthésie-Réanimation Chirurgicale, Laboratoire de Biochimie A,
Service de Pneumologie, Centre Hospitalo-Universitaire Bichat Claude Bernard, Paris, France
Several studies suggest that anesthetics modulate the immune response. The aim of this study was to investigate the effect of halothane and thiopental on the lung inflammatory response. Rats
submitted or not to intratracheal (IT) instillation of lipopolysaccharides (LPS) were anesthetized with either halothane (0.5, 1, or
1.5%) or thiopental (60 mg · kg
1) and mechanically ventilated for
4 h. Control rats were treated or not by LPS without anesthesia.
Lung inflammation was assessed by total and differential cell
counts in bronchoalveolar lavage fluids (BALF) and by cytokine
measurements (tumor necrosis factor-alpha [TNF-
], interleukin-6
[IL-6], macrophage inflammatory protein-2 [MIP-2], and monocyte
chemoattractant protein-1 [MCP-1]) in BALF and lung homogenates. In the absence of LPS treatment, neither halothane nor thiopental modified the moderate inflammatory response induced
by tracheotomy or mechanical ventilation. Cell recruitment and
cytokine concentrations were increased in all groups receiving IT
LPS. However, in halothane-anesthetized rats (halothane
1%), but not in thiopental-anesthetized rats, the LPS-induced lung inflammation was altered in a dose-dependent manner. Indeed,
when using 1% halothane, polymorphonuclear leukocyte (PMN)
recruitment was decreased by 55% (p < 0.001) and TNF-
, IL-6,
and MIP-2 concentrations in BALF and lung homogenates were
decreased by more than 60% (p < 0.001) whereas total protein
and MCP-1 concentrations remained unchanged. The decrease of
MIP-2 (observed at the protein and messenger RNA [mRNA] level)
was strongly correlated to the decrease of PMN recruitment (r = 0.73, p < 0.05). This halothane-reduced lung inflammatory response was transient and was reversed 20 h after the end of the
anesthesia. Our study shows that halothane
1%, delivered during 4 h by mechanical ventilation, but not mechanical ventilation
per se, alters the early LPS-induced lung inflammation in the rat,
suggesting a specific effect of halothane on this response.