Lidocaine increases the anti-inflammatory cytokine IL-10 following mechanical ventilation in healthy mice.

Background Mechanical ventilation ( MV) induces an inflammatory response that may result in (acute) lung injury. Lidocaine, an amide local anesthetic, has anti-inflammatory properties in vitro and in vivo, possibly due to an attenuation of pro-inflammatory cytokines, intracellular adhesion molecule-1 ( ICAM-1), and reduction of neutrophils influx. We hypothesized an attenuation of MV-induced inflammatory response with intravenously administered lidocaine. Methods Lidocaine ( Lido) (2, 4, and 8 mg/kg/h) was intravenously administered during 4 h of MV with a tidal volume of 8 ml/kg, positive end expiratory pressure 1,5 cmH₂O and FiO₂ 0.4. We used one ventilated control ( CON) group receiving vehicle. After MV, mice were euthanized, and lungs and blood were immediately harvested, and cytokine levels and ICAM-1 levels were measured in plasma and lung homogenates. Pulmonary neutrophils influx was determined in LEDER-stained slices of lungs. Anesthetic need was determined by painful hind paw stimulation. Results Lidocaine-treated animals ( Lido 2, 4 and 8 mg/kg/h) showed higher interleukin ( IL)-10 plasma levels compared to control animals. Lidocaine treatment with 8 mg/kg/h ( Lido 8) resulted in higher IL-10 in lung homogenates. No differences were observed in pro-inflammatory cytokines, ICAM-1, and pulmonary influx between the different ventilated groups. Conclusions Intravenously administered lidocaine increases levels of plasma IL-10 with infusion from 2, 4, and 8 mg/kg/h and pulmonary levels of IL-10 with 8 mg/kg/h in a murine mechanical ventilation model. Intravenously administered lidocaine appears to reduce anesthetic need in mice. [ABSTRACT FROM AUTHOR]