Patients with complex CHDs are at risk for impaired neurological development. There is too little knowledge about the effects of cardiac catheterisation under conscious sedation on electrocortical activity and cerebral oxygenation. This pilot study describes extended neurological function monitoring during paediatric cardiac catheterisation.

We conducted a prospective single-centre study including 52 patients with a median age and body weight of 3.5 [0–17] years and 15.3 [3.7–69.2] kg. Electrocortical activity and cerebral oxygenation were monitored via amplitude-integrated electroencephalography and near-infrared spectroscopy.

The median duration of extended monitoring was 130 [80–275] minutes. After propofol administration, amplitude-integrated electroencephalography amplitudes increased (p < 0.01) with a concomitant change in background patterns from continuous to high voltage in 45 patients (86.5%), while near-infrared spectroscopy decreased in tissue oxygenation index [p < 0.01] as did ΔHb. Propofol in one patient caused a rapidly reversible transition from high voltage to flat tracing and burst-suppression pattern. Cardiac interventions and arrhythmias caused short-term variations in near-infrared spectroscopy but had no significant impact on electrocortical activity.

Paediatric cardiac catheterisation under conscious sedation is associated with a high degree of patient safety. Extended monitoring of neurological function may be crucial to minimise risks and adjust conscious sedation levels, especially in high-risk patients.