Use of impedance cardiography to monitor haemodynamic changes during laparoscopy in children.

METHODS: Haemodynamic changes were measured noninvasively using impedance cardiography (ICG) in 30 ASA I children during laparoscopic varicocelectomy under general anaesthesia. After induction and intubation, mechanical ventilation was started, then pneumoperitoneum (PP) was created. During the course of anaesthesia, values of endtidal CO2 pressue (PECO2), peak inspiratory airway pressure (PIP), heart rate (HR), mean arterial blood pressure (MABP), stroke volume index (SVI), cardiac index (CI) and systemic vascular resistance index (SVRI) were recorded at 1 min intervals. We analysed four periods: T1, before induction; T2, after induction; T3, during PP; T4, after desufflation of PP until awake.
RESULTS: After induction of anaesthesia a significant reduction of HR, MABP and CI was recorded. Creating PP together with the use of a 15 degrees head down tilt resulted in a further drop in CI, mainly caused by the reduction of SVI, and an elevation of MABP and SVRI. We measured a 25% total decrease of CI.
CONCLUSION: Our patients tolerated this significant reduction of cardiac output well. We have demonstrated that ICG can be used to track the haemodynamic changes caused by PP in children, and suggest that this type of monitoring is useful in this group of age during laparoscopy.