الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
 |  | from | 16 |  |  |
| | | from | 16 | | |
Abstract
Respiratory failure is a syndrome in which the respiratory system fails to maintain an adequate gas exchange resulting in hypoxemia with or without concomitant hypercapnia. Respiratory failure is classified as type I (PaO2 of <60mmHg with a normal or low PaCO2), Type 2 (a PaO2 of <60mmHg and a PaCO2 of >45mmHg). Respiratory failure type II can be further classified as acute, acute on chronic or chronic.
The diaphragm is a dome-shaped musculofibrous septum that separates the thoracic from the abdominal cavity. It functions in breathing. During inhalation, the diaphragm contracts and moves in the inferior direction, thus enlarging the volume of the thoracic cavity. This reduces intra-thoracic pressure which helps to draw air into the lungs.
While mechanical ventilation (MV) is life-saving in patients with acute respiratory failure, prolonged mechanical ventilation is associated with numerous potential complications especially diaphragmatic dysfunction which may lead to difficulties in weaning from MV accounting for longer hospital stay and higher mortality.
Current techniques for monitoring respiratory muscle activity during mechanical ventilation are specialized and relatively invasive. Visualizing diaphragm excursion during inspiration by ultrasound may permit non-invasive monitoring.
Sonographic evaluation of the diaphragm has recently started to gain popularity in the ICU as it can assess the characteristics of diaphragmatic movement such as amplitude, force and velocity of contraction so it can be used in assessment and follow up of patients with diaphragmatic weakness or paralysis, in terms of patient–ventilator interactions during controlled or assisted modalities of mechanical ventilation and can be potentially helpful to understand weaning failure from mechanical ventilation.
The aim of the work is to evaluate diaphragmatic excursion using ultrasonography in mechanically ventilated patients on different modes of ventilation and its change overtime.
This study is a prospective observational study conducted on 61 mechanically ventilated patients admitted to the Critical Care Medicine Department in Alexandria Main University Hospital in the period from 1\6\2014 to 30\11\2014.
Patients were divided into three main groups; Group I: patients on controlled mechanical ventilation, Group II: patients on Assisted mechanical ventilation and Group III: patients on spontaneous mechanical ventilation. Patients were further divided into two groups; Group A: patients without diaphragmatic dysfunction and Group B: patients with diaphragmatic dysfunction.
Diaphragmatic excursion was measured once daily in all mechanically ventilated patients using M-mode ultrasonography. Ultrasonographic diaphragmatic dysfunction was diagnosed if an excursion was < 10 mm.
The three groups were compared regarding diaphragmatic excursion, weaning from mechanical ventilation, mortality, total ventilatory days and length of hospital stay. Group A and B were also compared regarding weaning failure, mortality, total ventilatory days and length of hospital stay.