Intraoperative use of transoesophageal Doppler to predict response to volume expansion in infants and neonates.

BACKGROUND Volume expansion (VE) in neonates or infants during volatile anaesthesia may lead to fluid overload if inappropriate. Transoesophageal Doppler (TED), a non-invasive cardiac output monitoring technique, can provide a comprehensive estimation of the volaemic status. We evaluated whether intraoperative TED-derived parameters can predict volume responsiveness. METHODS Neonates and infants under general anaesthesia without myocardial dysfunction were prospectively included when the attending anaesthetist, blinded to TED measurements, decided to provide VE based on clinical appreciation and standard monitoring data. Standard and TED-derived data were recorded before and after VE. After VE, patients were classified as responders and non-responders, if their indexed stroke volume (iSV) increased by more than 15% or not, respectively. The attending anaesthetist assessment of VE responsiveness was recorded at the end of VE. RESULTS Fifty patients aged 42 (4) post-conceptional weeks were included, among which 26 (52%) were responders. Baseline iSV was the only parameter associated with VE responsiveness. Baseline iSV was fairly correlated with VE-induced changes in iSV (ρ=-0.64) and was associated with an area under the receiver operating characteristic curve of 0.90 (0.80, 0.99). Using a cut-off of 25 ml m(-2), baseline iSV predicted volume responsiveness with a sensitivity of 92% and a specificity of 83%. Attending anaesthetists' assessment of VE effectiveness agreed only moderately with TED measurements of iSV changes. CONCLUSIONS TED-derived iSV measurement during volatile anaesthesia is useful to predict and follow VE responsiveness in neonates and infants without myocardial dysfunction.