ABSTRACT
This chapter reviews and discusses ventilation therapies for clinical acute
lung injury (ALI) and the acute respiratory distress syndrome (ARDS). Emphasis is on the concept of ventilator induced lung injury (VILI), and
how it can be minimized or prevented by specific ventilation strategies.
Acute pulmonary injury from mechanical ventilation in humans is indistin-
guishable from injury caused by many other processes associated with acute
respiratory failure and ARDS. In order to treat the severe hypoxemia pre-
sent in patients with ALI=ARDS, mechanical ventilation is generally required. However, added lung injury from ventilation therapy can have a
considerable negative impact on the morbidity and mortality of affected patients. The concept that mechanical ventilation per se is injurious to
the lungs, and that it can generate and exacerbate local and systemic inflam-
matory responses, has led to a reassessment of ventilation strategies for
patients with ALI=ARDS as detailed in this chapter. The aims of lung protective ventilation strategies are twofold: (1) to limit the injurious effect
of mechanical forces on the lung itself; and (2) to modulate or prevent the
development of a systemic inflammatory response. This chapter highlights
experimental and clinical evidence in support of the biotrauma theory of
lung injury and multiorgan failure in ALI=ARDS, and how it impacts current thinking on lung protective ventilation strategies. Discussion includes
the unique properties of the injured lung, and their relevance for the pathophysiology of VILI. In addition, the clinical literature on different ventila-
tory strategies is reviewed in detail in terms of their effectiveness in
improving the outcomes of patients with ALI=ARDS while protecting the lungs from iatrogenic injury.
