PURPOSE:Endotracheal intubation (ETT) produces tracheitis even during short periods of exposure. The effects of mask ventilation with positive pressure ventilation may also result in some level of tracheal injury. We hypothesize that endotracheal intubation produces more tracheitis than face mask ventilation.
METHODS:All animals received broad spectrum antibiotics for 72 hours prior to the experiments. The anesthetized pigs (30 kg) were mechanically ventilated using either an endotracheal tube (n=7) or a mask (nose cone) (n=7) for 6 hours. In both groups the tracheal lavage was performed using a modified ETT. The recovered lavage was analyzed for polymorphonuclear cells (PMN) and cytokine levels (TNF-α, IL-1β, IL-6, and IL-8). The cytokine levels were measured using the R&D ELISA assay with antibodies specific for porcine cytokines.
RESULTS:We observed a significant elevation of PMN in the intubated (89%) versus the mask (12%) group. In absolute numbers the PMN in the intubated group were 30 fold greater than in the mask group. For IL-6 the median value was: 0 pg/ml in the mask group and 80 pg/ml in the intubated animals. Lavage levels of IL-1 β, IL-8 and TNF-α were also elevated at 6 hours.
CONCLUSION:Our study confirms that inflammatory markers are released in response to uncomplicated endotracheal intubation but not with mask ventilation. We consistently found evidence of inflammation in the ETT group.
CLINICAL IMPLICATIONS:The observed differences in inflammatory reactivity between mask ventilation and endotracheal intubation suggests the need for more caution in selecting airway devices.
DISCLOSURE:Carlos Puyo, University grant monies The largest finnacial support for my research comes from the department of Anesthesiology and Critical Care at St. Louis University; Grant monies (from sources other than industry) My salary comes exclusively from St. Louis University.; Grant monies (from industry related sources) Respironics Inc, had supported in part my animal research. I am not a speaker and I have no financial interest in this company.; Shareholder no; Employee no; Fiduciary position (of any organization, association, society, etc, other than ACCP no; Consultant fee, speaker bureau, advisory committee, etc. no; No Product/Research Disclosure Information