Inclusion Criteria:

• Adult ICU patients in the Mayo Clinic Rochester who undergo mechanical ventilation,
• Patients who meet at least 2 of the following criteria within 2 hours preceding intubation:
• Heart rate measurement is within 2 hours preceding intubation:
  • Heart rate > 100 beats per minute.
• BUN, pH, Creatinine, and HCO3 measurements are from the most recent laboratory data prior to intubation:
  • BUN > 25 mg/dL;
  • pH < 7.25;
  • Creatinine > 2.0 mg/dL;
  • HCO3 < 20 mEq/L.

Exclusion Criteria: 

• Patients who decline research participation.
• Patients who are mechanically ventilated transiently for a procedure.
• Patients with documented history of neuromuscular disorder or diaphragmatic paralysis at the time of mechanical ventilation.
• Patients who underwent thoracic or abdominal surgery within 1 month of study enrollment or during the current hospitalization.
• Patients who cannot undergo neuromuscular ultrasound, due to the presence of medical tubes and dressings at the site of ultrasound transducer application.
• Patients who are receiving palliative care/comfort measures only.