The study is designed to use the lung ultrasound to assess the effect of intermittent lung recruitment during cardiopulmonary bypass in cardiac surgeries on extra vascular lung water.

Significant respiratory dysfunction is a common problem after cardiac surgery, with an incidence of about 25%. the formation of atelectasis appears to be the primary factor responsible for increased intrapulmonary shunt after cardiac surgery with CPB. The investigators will use the lung ultrasound to evaluate the effects of intermittent recruitment of the lungs during CPB on extra vascular lung water (EVLW).

Objectives :

To evaluate the effect of intermittent lung recruitment during CPB in cardiac surgery on:

Lung ultrasound score (LUS),Oxygenation at different times postoperatively,Time for extubation and length of ICU stay

sixty patients aged from 18-60 years old, scheduled for elective cardiac surgery with CPB will be included in the study. Patients will be randomly allocated into one of two groups: Group A (n=30): will receive intermittent lung recruitment during CPB.Group B (n=30): control group.

Inclusion Criteria:

• Adult patients aged (18-60 years),
• elective valvular cardiac surgery with cardiopulmonary bypass (CPB).

Exclusion Criteria:

• • Emergency surgeries.

  • coronary artery bypass graft surgery
  • patients requiring re-exploration in the immediate postoperative period (within 2hours)
  • left Ventricular ejection fraction less than 40%
  • patients with preoperative congestive heart failure, cardiogenic shock , preoperative pulmonary edema
  • pre-existing severe chronic pulmonary dysfunction (defined as pulmonary disease requiring home oxygen therapy or causing shortness of breath after 1 to 2 flights of stairs)
  • Morbid obesity
  • Renally impaired patients with creatinine more than 2 mg/dl

numbered, sealed opaque envelope.