It remains to be elucidated whether the Trendelenburg position increases intracranial pressure (ICP). ICP can be evaluated by measuring the sonographic optic nerve sheath diameter (ONSD). We investigated the effect of the isolated Trendelenburg position on ONSD in patients undergoing robot-assisted laparoscopic radical prostatectomy. Additionally, we evaluated the effect of the Trendelenburg position combined with pneumoperitoneum on ONSD. Twenty-one patients scheduled for robot-assisted laparoscopic radical prostatectomy were enrolled. Sonographic ONSDs and hemodynamic parameters were measured at specific time points: in the supine position after induction of anesthesia, 3 min after the steep Trendelenburg position (35° incline), 3 min after the steep Trendelenburg position combined with pneumoperitoneum, and in the supine position after desufflation of the pneumoperitoneum. The ONSD 3 min after the steep Trendelenburg position was significantly higher than that of the supine position after induction of anesthesia (5.1 ± 0.3 mm vs. 4.5 ± 0.4 mm). In addition, the ONSD 3 min after the steep Trendelenburg position combined with pneumoperitoneum was higher than that of the supine position after induction of anesthesia (4.9 ± 0.4 mm vs. 4.5 ± 0.4 mm). The ONSD in the supine position after desufflation of the pneumoperitoneum was similar to that in the supine position after induction of anesthesia. Use of the isolated steep Trendelenburg position, for even a short duration, increased the sonographic ONSD, providing a better understanding of the effect of only a transient steep Trendelenburg position on ONSD as a surrogate measure for ICP.

A hypertrophied posterior tibial tendon (PTT) has been considered to be an important morphologic parameter of PTT dysfunction (PTTD). Previous research has demonstrated that the PTT thickness (PTTT) is correlated with early signs of PTTD. However, the thickness is different from hypertrophy. Thus, we devised the PTT cross-sectional area (PTTCSA) as a new predictive parameter for diagnosing the PTTD. The PTT data were acquired from 14 patients with PTTD and from 20 normal individuals who underwent ankle magnetic resonance imaging. We measured the PTTT and PTTCSA at the PTT on the ankle magnetic resonance imaging. The mean PTTT was 2.43 ± 0.39 mm in the normal group and 3.40 ± 0.42 mm in the PTTD group. The average PTTCSA was 16.10 ± 4.27 mm² in the normal group and 26.93 ± 4.38 mm² in the PTTD group. The receiver operator characteristic analysis curve demonstrated that the highest predictive value of the PTTT was 3.07 mm, with 85.7% sensitivity, 85.0% specificity. The highest predictive value of the PTTCSA was 22.54 mm ² , with 92.9% sensitivity, 90.0% specificity. Our findings suggest that the PTTCSA was a more valid predictor of PTTD, even though the PTTT and PTTCSA were both significantly associated with PTTD.

Micro-emboli have been reported to occur commonly during arthroscopic surgery, which is frequently performed as an orthopedic surgical procedure. We here report a patient who experienced unilateral postoperative visual loss after a hip arthroscopy using irrigation fluid in the supine position without any evidence of external compression to either eye throughout the surgical procedure. Retinal fundoscopy suggested that the patient had central retinal artery occlusion, one of the causes of the postoperative visual loss. This case suggests that arthroscopic surgery may pose a substantial risk for paradoxical air embolism, such as central retinal artery occlusion, and suggests the need to prevent the entry of micro-air bubbles during such a type of surgery.

Background and Objectives: Remimazolam is a recently introduced benzodiazepine that has been increasingly adopted as an alternative to propofol. Although several trials have compared remimazolam with propofol, these studies have primarily focused on induction-related hypotension in non-gynecologic settings. To the best of our knowledge, both intraoperative hypertension and hypotension have not been systematically evaluated throughout the full anesthetic course in the specific physiologic context of robot-assisted laparoscopic gynecologic surgery performed in the steep Trendelenburg position with pneumoperitoneum. Materials and Methods: In this retrospective study, propensity score matching was performed to minimize selection bias. The demographic data of 694 patients, along with the incidence of intraoperative hypertension and hypotension, were collected through a review of medical records. Results: A total of 694 patients met the selection criteria, all of whom underwent total intravenous anesthesia (TIVA) using either remimazolam (n = 321) or propofol (n = 373). After propensity score matching, 317 pairs were analyzed. The incidence of intraoperative hypertension was higher in the remimazolam group (66.2% vs. 52.1%; p < 0.001), whereas hypotension was more frequent in the propofol group (12.0% vs. 5.4%; p = 0.003). Conclusions: TIVA with remimazolam was associated with a higher incidence of intraoperative hypertension compared to propofol, whereas propofol was more likely to cause hypotension in patients undergoing laparoscopic gynecologic surgery.

Background and Objectives: The Analgesia Nociception Index (ANI), a surrogate marker derived from heart rate variability (HRV) analysis, has been validated for assessing the balance between antinociception and nociception during propofol anesthesia. The ANI continuously monitors this balance, with values above 50 indicating optimal analgesia. By adjusting analgesic administration based on ANI values, anesthesiologists can provide more personalized intraoperative pain control. Remimazolam, a novel benzodiazepine anesthetic lacking intrinsic analgesic properties, exhibits distinct HRV patterns compared to propofol. Considering these differences, the validity of the ANI during remimazolam anesthesia remains uncertain. We evaluated the validity of the ANI by assessing its ability to detect nociceptive stimuli during remimazolam anesthesia. Materials and Methods: In total, 28 patients were administered general anesthesia using remimazolam and remifentanil. We evaluated changes in the ANI before and after tetanic stimulation. In addition, we investigated the association between hemodynamic responses during surgical incisions and changes in the ANI. Results: Tetanic stimulation resulted in a significant (p < 0.001) reduction in the ANI, from 62.0 (interquartile range [IQR] 50.5–76.0) to 44.0 (IQR 37.0–55.5). Of the 13 patients who experienced hemodynamic responses during surgical incision, the ANI significantly decreased from 63.2 ± 13.6 to 36.9 ± 13.8 following noxious surgical stimulation (p < 0.001). Conclusions: The ANI reflects the dynamic equilibrium between antinociception and nociception during remimazolam-based general anesthesia.