["This study was designed to assess the ability of the stroke volume respiratory variation (ΔrespSV) determined by oesophageal Doppler monitoring (ODM) to predict the response to volume expansion (VE) during pneumoperitoneum. The predictive value of ΔrespSV was evaluated according to the concept of the 'grey zone'.", 'Patients operated on laparoscopy and monitored by ODM were prospectively included. The exclusion criteria were frequent ectopic beats or preoperative arrhythmia, right ventricular failure, and spontaneous breathing. Haemodynamic parameters and oesophageal Doppler indices [stroke volume (SV), peak velocity (PV), cardiac output (CO), corrected flow time (FTc), respiratory variation of PV (ΔrespPV) and SV (ΔrespSV)] were collected before and after VE. Responders were defined as a ≥15% increase in SV after VE.', 'Thirty-eight (64%) of the 59 patients were responders. A cut-off of >14% ΔrespSV predicted fluid responsiveness with an area under the ROC curve (AUC) of 0.92 [95% confidence interval (CI): 0.82-0.98, P<0.0001]. The grey zone of ΔrespSV ranged between 13 and 15%. With an AUC of 0.71 (95% CI: 0.56-0.83, P=0.005), ΔrespPV fairly accurately predicted fluid responsiveness. FTc was unable to accurately predict fluid responsiveness.'] Does respiratory stroke volume variation assessed by oesophageal Doppler monitoring predict fluid responsiveness during laparoscopy?