Acute respiratory distress syndrome is an acute, diffuse, inflammatory form of lung
injury and life-threatening condition in seriously ill patients, characterized by poor
oxygenation, pulmonary infiltrates, and acute onset. on a microscopic level, the disorder
is associated with capillary endothelial injury and diffuse alveolar damage Acute
respiratory distress syndrome is an acute disorder that starts within seven days of the
inciting event and is characterized by bilateral lung infiltrates and severe progressive
hypoxemia in the absence of any evidence of cardiogenic pulmonary edema. According to the
Berlin definition, Acute respiratory distress syndrome is defined by acute onset,
bilateral lung infiltrates on chest radiography or computed tomography scan of a
non-cardiac origin, and a PaO2/FiO2 ratio of less than 300 mm Hg. The Berlin definition
differs from the previous American-European Consensus definition by excluding the term
acute lung injury; it also removed the requirement for wedge pressure < 18 mm Hg and
included the requirement of positive end-expiratory pressure or continuous positive
airway pressure of greater than or equal to 5 cm H20.
Once Acute respiratory distress syndrome develops, patients usually have varying degrees
of pulmonary artery vasoconstriction and may subsequently develop pulmonary hypertension.
Acute respiratory distress syndrome carries a high mortality, and few effective
therapeutic modalities exist to combat this condition Although the Berlin definition of
Acute respiratory distress syndrome was a major step forward, some of its limitations
were recognized soon after publication. Specifically, it was recognized that its
requirement for noninvasive ventilation or invasive ventilation could not be met in
settings in which these modalities are not available So consensus conference of 32
critical care develop new global Acute respiratory distress syndrome definition that use
high flow nasal oxygen , pulse oximetry in place of arterial blood gas and use of Lung
ultrasound to suit limited resource setting .
Lung computed tomography scan is the gold standard in diagnosis of Acute respiratory
distress syndrome can provide useful diagnostic information and assess the benefit of
treatment. However, this procedure is done in a computed tomography unit under
cardiorespiratory monitoring with an increased risk to the patient.
Diagnostic and lung exploratory ultrasound is a rapidly evolving technique used in the
Intensive care unit environment, being considered noninvasive, radiation-free, cheap, and
easy to perform .
Lung ultrasound has been validated for hemodynamic management, pleural effusions,
pulmonary edema, pneumothorax detection, parenchymal consolidation, and central vein
catheter placement .
simple and short Lung ultrasound examination could predict prone position oxygenation
response in Acute respiratory distress syndrome patients .
Scores based on detection of B-lines (the sonographic sign of increased lung density
associated with interstitial syndrome) and on consolidation have been correlated with
global and regional lung aeration as assessed by computed tomography chest.
Lung ultrasound has been proposed as an accurate bedside and radiation free technique for
evaluation of lung consolidations and for follow-up of aeration changes in response to
interventions.
However lung us scoring system hasn't been included in Acute respiratory distress
syndrome definition and didn't prefer image modality in diagnosis of Acute respiratory
distress syndrome , therefore our study will explore the feasibility and accuracy of lung
us score performed bedside to differentiate between Acute respiratory distress syndrome
and non Acute respiratory distress syndrome patient compared to lung computed tomography
.