Jin Hee Ahn

Background: Optimizing fluid therapy is critical for maintaining hemodynamic stability in elderly patients undergoing major surgeries. Dynamic arterial elastance (Eadyn), defined as the ratio of pulse pressure variation (PPV) to stroke volume variation (SVV), has been proposed as a predictor of fluid responsiveness, especially in challenging conditions like prone-positioned spine surgery under general anesthesia. Methods: Hemodynamic parameters were measured before and after fluid loading with 500 mL of crystalloid solution. Patients were classified as responders or non-responders based on a ≥15% increase in mean arterial pressure (MAP) post-fluid administration. Predictive performance of these parameters was assessed using receiver operating characteristic (ROC) analysis. Results: Of the 37 patients, 15 were classified as responders and 22 as non-responders. Eadyn demonstrated poor predictive performance (AUC = 0.508). In contrast, SVV (AUC = 0.808), PPV (AUC = 0.738), and C (AUC = 0.741) exhibited moderate to high predictive ability. Responders exhibited significantly higher baseline SVV, PPV, and net arterial compliance compared to non-responders. Conclusions: Dynamic arterial elastance (Eadyn) showed limited predictive ability for fluid responsiveness in elderly patients undergoing spine surgery in the prone position. In contrast, stroke volume variation (SVV), pulse pressure variation (PPV), and net arterial compliance (C) demonstrated superior reliability, with SVV emerging as the most accurate predictor.

Accurate assessment of mitral regurgitation (MR) is critical during mitral valve repair surgery. However, anesthesia may influence the degree of mitral regurgitation by changing pre- and after-load or cardiac contractility. Therefore, we compared changes in mitral regurgitation by total intravenous anesthesia (TIVA) and inhalation anesthesia in patients with pre-existing mitral regurgitation. This was a double-blind randomized controlled study conducted at a tertiary care center in 2018. Fifty-four mitral regurgitation patents undergoing elective cardiac surgery were randomly assigned to receive TIVA or isoflurane. Primary endpoint was change of regurgitation volume by anesthesia. The reduction of regurgitation volume by anesthesia was greater in the isoflurane group than in the TIVA group (mean (95% confidence interval CI): −0.20 (−6.15, 5.75) vs. −9.66 (−15.77, −3.56), mL·beat⁻¹, p = 0.0266) and this phenomenon was more prominent with severe mitral regurgitation (grade 3 or 4) (mean (95% CI): −0.33 (−9.10, 8.44) vs. −16.20 (−24.22, −8.18), mL·beat⁻¹, p = 0.0079). Among patients with MR grade 3 or 4, 94% remained the same with TIVA during anesthesia compared to 56% with isoflurane. In conclusion, TIVA maintained the pre-anesthetic state of mitral regurgitation relatively well, while the severity of mitral regurgitation tended to decrease with isoflurane anesthesia.