TY - JOUR
T1 - Do airway secretions play an underappreciated role in acute respiratory distress syndrome?
AU - Graf, Jerónimo
AU - Marini, John J
PY - 2008/2
Y1 - 2008/2
N2 - PURPOSE OF REVIEW: We review the evidence that airway secretions may have an underappreciated role in acute respiratory distress syndrome, contributing to physiologic disarrangements, ventilator dependence and perhaps to injury generation. As common manipulations of ventilator settings, position and fluid status have the potential to influence these problems, explorations into the secretion dynamics of acute lung injury may be fertile ground for developing therapeutic advances. RECENT FINDINGS: Principles that govern the interaction of airflow and airway fluids suggest that mobile fluids and secretions are pumped by well-selected ventilatory patterns toward the airway opening. Conversely, other selections may inhibit these fluids from clearance or encourage their translocation between lung regions. Recent laboratory work demonstrates that choices for tidal volume and positive end-expiratory pressure may localize or disperse proteinaceous lung edema or bacteria. Gravitational factors may interact with ventilatory pattern for benefit or harm. SUMMARY: Capability of ventilation and positioning to mobilize secretions implies the potential for clearance or containment of inflammatory mediators and infection. Ventilatory and positional prescriptions could be designed to meet one of either conflicting targets. Additional experimental and clinical investigations are required before adopting these proposed therapeutic principles into practice.
AB - PURPOSE OF REVIEW: We review the evidence that airway secretions may have an underappreciated role in acute respiratory distress syndrome, contributing to physiologic disarrangements, ventilator dependence and perhaps to injury generation. As common manipulations of ventilator settings, position and fluid status have the potential to influence these problems, explorations into the secretion dynamics of acute lung injury may be fertile ground for developing therapeutic advances. RECENT FINDINGS: Principles that govern the interaction of airflow and airway fluids suggest that mobile fluids and secretions are pumped by well-selected ventilatory patterns toward the airway opening. Conversely, other selections may inhibit these fluids from clearance or encourage their translocation between lung regions. Recent laboratory work demonstrates that choices for tidal volume and positive end-expiratory pressure may localize or disperse proteinaceous lung edema or bacteria. Gravitational factors may interact with ventilatory pattern for benefit or harm. SUMMARY: Capability of ventilation and positioning to mobilize secretions implies the potential for clearance or containment of inflammatory mediators and infection. Ventilatory and positional prescriptions could be designed to meet one of either conflicting targets. Additional experimental and clinical investigations are required before adopting these proposed therapeutic principles into practice.
KW - Acute respiratory distress syndrome
KW - Clearance of airway secretions
KW - Lung protective ventilation
KW - Mechanical ventilation
KW - Pneumonia
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U2 - 10.1097/MCC.0b013e3282f2f4cb
DO - 10.1097/MCC.0b013e3282f2f4cb
M3 - Review article
C2 - 18195625
AN - SCOPUS:38149051289
SN - 1070-5295
VL - 14
SP - 44
EP - 49
JO - Current opinion in critical care
JF - Current opinion in critical care
IS - 1
ER -