Acute respiratory distress (ARD) is one of the most frequent reasons for consultation and hospitalization in emergency medicine. The use of ultrasound methods as a diagnostic and clinical assessment tool in emergency medicine is increasingly important. As such, ultrasound is a simple, non-invasive means of assessing diaphragmatic function in the patient's bed. Several methods of ultrasound assessment of diaphragm function have been described. Among these different methods, the diaphragmatic excursion seems to have a better intra and interobserver reproducibility as well as a greater feasibility, in particular because of its speed of realization and its learning curve seeming faster in comparison with the measurement. of the thickening fraction. Measuring the diaphragmatic excursion could therefore ultimately represent a simple means of assessing respiratory function, both diagnostic and prognostic, in patients with acute respiratory distress in the emergency departments. The etiologies of acute respiratory distress in very elderly patients (i.e.> 75 years) admitted to the emergency reception service are multiple.

To our knowledge, there is no data available in the literature on the prevalence of diaphragmatic dysfunction and its short- and long-term course in this category of patients. The main objective of this study is therefore to assess the prevalence of diaphragmatic dysfunction and its evolutionary kinetics in patients over the age of 75 admitted for acute respiratory distress in the emergency medicine department.

Inclusion Criteria:

• Patient in spontaneous ventilation at the admission on emergency room

• Presence of acute respiratory distress defined by at least 1 of the following criteria:

  • Respiratory rate > 25/min and/or clinical signs of acute respiratory distress,
  • Hypoxia defined by Sp02 < 90 %,
  • Hypercapnia defined by PaC02 > 45 mmHg with respiratory acidosis defined by a pH value <7.35.

• Absence of opposition of the patient to his participation in the study and the use of his data or the trusted person if the state of the patient does not allow it.

Exclusion Criteria:

• Presence of a preexisting diaphragmatic dysfunction appearing in the history or the medical file of the patient and explored on the electro-physiological level,
• Patient with acute respiratory distress on arrival at the SAU with clinical criteria justifying immediate use of invasive mechanical ventilation and not allowing ultrasound measurements to be carried out or patient admitted to the SAU with mechanical ventilatory support from the outset,
• Poor command of the French language or state incompatible with the patient's understanding and / or informed adherence to the study protocol,
• History of surgery involving the integrity of the diaphragmatic muscle (diaphragm plication or diaphragmatic lumpectomy or placement of diaphragmatic pacemaker),
• Criteria for shock or severe hemodynamic instability,
• Intra-cranial hypertension.

Recruitment of all patients over the age of 75, presenting to adult emergency departments and in spontaneous ventilation and having at least one criterion of acute respiratory distress.