Background: Elevated plasma lactate has been shown to correlate with mortal
ity in patients with septic shock. Heat stress prior to sepsis has resulted
in reduction in acute lung injury and mortality. We investigated whether h
eat stress resulted in decreased plasma lactate concentration and protected
the lung by decreasing the inflammatory response to sepsis.
Results: Plasma lactate concentration was elevated in septic rats without p
rior heat stress. Lactic acid levels were significantly lower in heat-treat
ed septic rats (P<0.05) and were not significantly different when compared
with control rats. Septic rats with or without heat pretreatment had signif
icantly higher myeloperoxidase activity in the lung than did control groups
. Heat pretreatment did not prevent neutrophil infiltration or inflammatory
mediator production in the lung.
Conclusion: Prior heat stress ameliorates lactic acidemia in rat sepsis. He
at stress did not attenuate the pulmonary inflammatory process. The mechani
sm of heat-induced protection from lactic acidemia in sepsis needs to be fu
rther explored.