Statement of the problem:

• Does the thoracic block technique has effect on arterial blood gases, vital signs and lung compliance in children with atelectasis on mechanical ventilation? Null hyposis there is no effect of thoracic block technique on arterial blood gases, vital signs and lung compliance in children with atelectasis on mechanical ventilation.

Subjects:

The study targets the children from both sexes.diagnosed with atelectasis in intensive care unit. Sample size estimation will be carried out to determine the recruited number of children, selected randomly from Cairo University pediatric specialized hospital, Cairo to participate in the study,

Study design:

Randomized controlled clinical trial. Children will receive intervention type randomly, 22 child received percussion, vibration, modified postural drainage and the other 22 child will receive percussion, vibration, modified postural drainage and thoracic block technique.

Children will be assessed by measuring heart rate, respiratory rate,which reflect the physiological status, arterial blood gases which include partial pressure of oxygen (PaO2), partial pressure of carbon dioxide (PaCO2) and oxygen saturation (SaO2) and dynamic lung compliance which reflect clinical improvement of chest condition before and after ten days of receiving intervention

Inclusion Criteria:

1. age range from 4 months to 4 years.
2. diagnosed with pneumonia, receiving mechanical ventilation.
3. start from second day of admission to intensive care unit
4. have unilateral mild to moderate atelectasis according to medical referral.
5. should be vitally stable during the session.

Exclusion Criteria:

The children were excluded from the study if they had one of the following:

1. medically unstable ( examples: tachycardia and tachypnea)
2. uncontrolled convulsion.
3. rib fracture.
4. pneumothorax -