Re-Evaluation of Systemic Early Neuromuscular Blockade and Transthoracic Ultrasound Assessment of the Diaphragm

A growing body of evidence strongly suggests that mechanical ventilation injures the
respiratory muscles, particularly the diaphragm. Due to the deleterious effects of diaphragm
inactivity on diaphragm function, there are important concerns about the risk of diaphragm
weakness and difficult liberation from mechanical ventilation following neuromuscular
blockade. Sonographic measurements of diaphragm thickness provide a potentially useful window
for studying diaphragm injury and function during mechanical ventilation.

Patients enrolled in the ROSE trial (randomizing patients with moderate-severe acute
respiratory distress syndrome to receive neuromuscular blockade or control for 2 days) will
be eligible for participation in this study. Study patients will undergo regular diaphragm
ultrasound to assess diaphragm thickness and activity during the first week of the study.
Diaphragm function will be assessed by ultrasound on study days 7, 14, 21, and 28.

ROSETTA is designed to:

1. Test the feasibility of a multi-center evaluation of the diaphragm structure and
function by ultrasound during mechanical ventilation;

2. Determine whether neuromuscular blockade accelerates atrophy and dysfunction of the
diaphragm in patients with acute respiratory distress syndrome; and

3. Evaluate whether patients with greater diaphragm dysfunction exhibit worse functional
outcomes compared to patients without diaphragm dysfunction.

Inclusion Criteria:

1. Patients enrolled in the ROSE PETAL trial (adult patients with moderate-severe acute
respiratory distress syndrome who have received invasive mechanical ventilation for less
than 5 days)

Exclusion Criteria:

1. Patients expected to be extubated within 24 hours of screening for eligibility

2. Patients with a contraindication to chest ultrasonography (chest tubes inserted over
right lower chest wall; chest wall trauma)