Ability of dynamic arterial elastance to predict the efficacity of fluid and vasopressors to treat intraoperative hypotension ; Variations de l’élastance artérielle dynamique induites par l’expansion volémique et les vasopresseurs au bloc opératoire : une étude prospective bicentrique

Background: perioperative hypotension could lead to worse patient outcome. The two principal strategies to correct perioperative hypotension are vasopressor infusion and volume expansion. We hypothesized that dynamic arterial elastance (defined as the ratio between pulse pressure variations and stroke volume variations), could predict the efficacity of fluid and vasopressors to treat intraoperative hypotension (mean arterial pressure below 65 mmHg). Methods: we included 56 hypotensive and mechanically ventilated patients in the operating room. Each patient had volume expansion and neosynephrine infusion. Stroke volume and stroke volume variations were obtained using esophageal doppler and pulse pressure variations were measured through the arterial line. Pressure response to volume expansion was defined as an increase in mean arterial pressure≥10%. Results: volume expansion induced a decrease in dynamic arterial elastance in 68% of patients. Baseline dynamic arterial elastance was poorly correlated to the mean arterial pressure increase associated with volume expansion (r2=0.11;p=0.01). Dynamic arterial elastance value before volume expansion>0.65 predicted a mean arterial pressure increase≥10% with a sensitivity of 76% (95%CI=53-92%), a specificity of 60% (95%CI=42-76%). The area under receiver operating characteristics curve generated for baseline dynamic arterial elastance was 0.71 (95%CI=0.57 to 0.84). Neosynephrine infusion induced a decrease in dynamic arterial elastance in 89% of patients. Dynamic arterial elastance value before neosynephrine infusion≤0.78 predicted a mean arterial pressure increase≥10% with 76% (95%CI=62-87%) sensitivity and 67% (95%CI=22-96%) specificity. Conclusions: dynamic arterial elastance was not able to predict the efficacity of fluid and vasopressors to treat intraoperative hypotension in surgery patients under general anesthesia. ; Contexte : l’hypotension artérielle peropératoire peut altérer le pronostic des patients. Les deux principales stratégies pour corriger une ...