Validation study of the dynamic parameters of pulse wave in pulmonary resection surgery

In lung resection surgery, restrictive fluid therapy is recommended due to the risk of acute lung injury. In contrast, this recommendation increases the risk of hypoperfusion. Guided fluid therapy allows individualization of fluid intake. The use of dynamic volume response parameters is not validated during one-lung ventilation. The main objective is the validation of dynamic parameters, stroke volume variation (SVV) and pulse pressure variation (PPV), during lung resection surgery as fluid response predictors, after the administration of 250ml crystalloid volume loads, if IC<2.5ml/min/m² and if SVV≥8% and/or PPV≥10%.

Pilot, prospective, observational and single centre study. Twenty-five patients monitored with the PiCCO system were included during open lung resection surgery with the patient in a lateral position, one lung ventilation with tidal volume (TV): 6ml/kg and open chest. Hemodynamic variables were collected before and after volume loading. The results were classified into two groups: volume responders (increase IC≥10% and/or VSI≥10% after volume loading) and non-responders (no increase or increase IC<10% and/or VSI<10% after volume loading). We assess the diagnostic efficacy of SVV and PPV by analyzing the AUC (area under curve) in the ROC curves.

In the analysis of ROC curves, SVV and PPV did not reach a discriminative value (AUCSVV: 0.47; AUCPPV: 0.50), despite the decrease in the threshold value of SVV and PPV to initiate an overload of volume during one-lung ventilation, in lateral position and open chest.

The results obtained show that the values of the dynamic parameters of volume response (SVV≥8% and PPV≥10%) do not discriminate against responders patients and non-responders during open lung resection surgery.