The purpose of this research study is to help determine if the cuff of an endotracheal tube ( ETT) ( also known as a breathing tube)can be seen by ultrasound and to determine if visualization of this tube corresponds with correct tube depth. You are being asked to participate because you will be undergoing a cardiac catherization procedure which will involve endotracheal intubation.

Ultrasound is a safe technology that your doctor could possibly use to see the breathing tube. Right now, x-rays, which come with their own risks, are being used for this purpose. We are trying to see if we can avoid using x-rays.

This is a local study with 1 location. The study will enroll a total of 71 people. There is no sponsor for this study.

If you enter the study, in the cardiac catheterization lab, after the anesthesiologist has done his part (placed the breathing tube while you are asleep and obtained the x-ray), we will use the ultrasound to check the position of the breathing tube. To help us see the breathing tube better, we will put some fluid in the cuff ( the balloon at the tip of the breathing tube). The tube may be repositioned as needed based on the chest x-ray. The entire procedure is estimated to take no more than 10 minutes.

Inclusion Criteria:

• English and Spanish-speaking patients
• Age 0-21 years
• Elective cardiac catheterization procedure
• Endotracheal intubation with a cuffed ETT

Exclusion Criteria:

• Abnormal neck/tracheal anatomy
• Emergent cardiac catherization procedure
• Endotracheal intubation with an uncuffed ETT
• Inability to consent

Patients scheduled to undergo elective cardiac catherization procedures will be screened for eligibility.