The purpose of this study is to investigate the immediate combined effects of Manual Hyperinflation and standard Physical therapy program on lung recruitment and secretion mass in mechanically ventilated pediatric patients aged between 10-15 years 'old

In developing countries, lower respiratory tract infection is a major cause of death in children, with severely ill patients being admitted to the critical-care unit. While physical therapists commonly use the manual hyperinflation (MHI) technique for secretion mass clearance in critical-care patients, its efficacy has not been determined in pediatric patients.

Manual hyperinflation is a frequently maneuver used in critically ill intubated and mechanically ventilated patients. With MHI, patients are disconnected from the mechanical ventilator after which their lungs are temporarily ventilated with a manual ventilation bag. so, by applying a larger than normal volume at a low inspiratory pause and expiration with a high expiratory flow, MHI is suggested to mimic a normal cough.

Propagation of airway secretions from the smaller toward the larger airways, then allows for easy removed of airway secretions with the airway suction. finally, MHI could prevent airway plugging and even promote alveolar recruitment. so the aim of the study is to enhance lung recruitment using MHI combined with standard Physical therapy program

Inclusion Criteria:

• The patients will be aged 10-15 years,
• receiving mechanical ventilation via an endotracheal tube for at least 24 h
• presenting with vital signs in the normal range.
• All patients are suffering from lower respiratory tract infection like pneumonia, bronchitis and acute exacerbation of bronchiectasis

Exclusion Criteria:

• Patients with history of thoracic surgery
• Patients with pneumothorax or acute respiratory distress syndrome
• Patients with severe acute head injury
• Patients use inotropes and vasopressors drugs
• Patients with severe Broncho pleural fistula, rib fracture, emphysema bullae, lung abscess, patients with history of preterm birth or heart disease.
• Patients who requiring mechanical ventilation with a peak inspiratory pressure (PIP)

data will not be available to other researchers

using sealed envelopes,