This study investigates the level of agreement of two non-invasive cardiac output monitors (transthoracic echocardiography and electrical cardiometry) in young children under anesthesia.

Young children are particularly prone to hemodynamic instability during the perioperative period which, in turn, may lead to organ morbidity. Currently, in routine surgical procedures in otherwise healthy children, hemodynamic status in the perioperative period is primarily assessed by non-invasive systemic blood pressure management. While this approach can detect systemic arterial hypotension, it does not provide us with guidance on whether the decrease in blood pressure is the result of changes in cardiac output and/or in systemic vascular resistance. This information would be important to know since treatment modalities may differ.

Recent technical development in electrical cardiometry allows us to non-invasively monitor cardiac output. The accuracy of the method has been validated in neonatal and paediatric cohorts, and electrical cardiometry is now regularly used to monitor cardiac output in the perioperative setting. Nevertheless, the trending patterns of cardiac output in otherwise healthy young children undergoing routine surgical procedures, still need to be described. Due to technical aspects, transthoracic echocardiography is now recognised as "gold-standard" measurement of cardiac output in paediatric patients.

This study is based on a commonly and non-invasively applied monitoring equipment (ICON) which is now regularly used on anesthetized children for the detection of cardiac output during the perioperative period. The primary objective of this validation study is to confirm the non-inferiority of cardiac output measurement with electrical cardiometry versus transthoracic echocardiography in young children ( 0-17 months of age) during the perioperative period.

The secondary objective is to describe the trending aspects of cardiac output during the anaesthesia until the recovery.

Inclusion Criteria:

1. Age 0 to 17 months included
2. Greater than 36 weeks post-menstrual age (PMA) on the day of the study
3. Undergoing general anaesthesia for surgery that is expected to last more than 30 minutes (combines anaesthesia and surgical time)
4. Parental/guardian understands and reads French and permission (informed consent) obtained
5. ASA 1-3 status

Exclusion Criteria:

1. Structural/anatomical anomaly or other circumstances (e.g., patient positioning) making it difficult to apply the sensors to the body or limiting the feasibility of the TTE
2. Any Congenital heart diseases
3. Known allergy to electrodes' glue
4. Thoracic, cardiac and head surgery
5. Traumatic surgery with hemodynamic instability

Project population: infants (ASA1-3 status) up to 18 months of age undergoing a surgical procedure under general anaesthesia.