<prompt> Which of the following is the necessary pre-operative investigation which has to be done in a patient with Downs syndrome posted for surgery?CT BrainEchocardiographyUltrasound AbdomenX-Ray cervical spine  <response>: Downs syndrome is associated with cardiac manifestations such as Endocardial cushion defect, ASD, VSD and Tetrology of fallot. So echocardiography is the necessary pre-operative investigation to be done before surgery in a patient with Downs syndrome. Ref: Harrisons Principles of Internal Medicine, 16th Edition, Page 1382 