The mechanical ventilator: a potentially dangerous tool.

Mechanical ventilation is an important therapeutic technique for patients with respiratory failure. Nonetheless, it can be potentially dangerous, worsening by itself pre-existing lesions and producing new ones. The author carefully reviews the results of a number of long term studies in large animals, which highlight the factors causing ventilator-induced lung injury. When the pathology is not manageable with non invasive approach, invasive mechanical ventilation should be tailored to the patient to avoid iatrogenic damage.