Endobronchial tube misplacement is serious complication during general anesthesia in pediatric patients. Correct placement of the endotracheal tube (ETT) in the trachea is crucial. Several methods have been suggested for determination of correct ETT placement. However, to date, auscultation of the left and right lung is the standard of care and the only ubiquitary available method with an error rate of up to 12%. Electrical impedance tomography (EIT) is a new non-invasive method for evaluation of left and right lung ventilation. In this study the investigators investigate the potential role of EIT for proper placement of pediatric endotracheal tubes.

Several methods have been suggested for determination of correct ETT placement. These include for example the marker method, the mainstem method or the formula method. However, to date, auscultation of the left and right lung is the standard of care and the only ubiquitary available method with an error rate of up to 12%. Electrical impedance tomography (EIT) is a new non-invasive method for evaluation of left and right lung ventilation. In this study the investigators investigate the potential role of EIT for proper placement of pediatric endotracheal tubes. For this purpose, pediatric patients are routinely intubated for cardiac catheterization using the mainstem method or 3xETT size method. Placement of the ETT is then verified by intraoperative fluoroscopy and lung ventilation is verified by EIT.

Inclusion Criteria:

• written informed consent from the parents
• endotracheal intubation with a standard endotracheal tube

Exclusion Criteria:

• refusal of written informed consent
• severe lung diseases
• contraindication for use of electrical impedance tomography