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Purpose An electromyographic (EMG) tube is sometimes used for vagal nerve monitoring during neurosurgery. Some characteristics of an EMG tube are different from those of a normal endotracheal tube. Although postoperative laryngeal edema (PLE) may occur and reintubation may be required in some patients in whom an EMG tube is used, its relevance to these events has not been investigated in detail. Our goal was to determine the relevance of an EMG tube to the development of PLE and the need for reintubation. Methods A retrospective study was conducted in 900 patients after neurosurgery from 2012 to 2018. Severe PLE occurrence or the requirement for postoperative reintubation were compared between the EMG tube (E) group and the Normal tube (N) group, using a propensity score (PS) matching analysis Results After PS matching, severe PLE incidence (n = 2/20, 10.0%) in the E group was significantly higher than that (0/80, 0%) in the N group. There was no significant difference in the incidence of reintubation between the E group (1/20, 5.0%) and the N group (0/80, 0%). Conclusion Electromyographic (EMG) tube use was significantly associated with higher incidence of severe PLE., Author(s): Hiroki Matsushita [sup.1], Kazuhiro Shirozu [sup.1], Kaoru Umehara [sup.2], Kenji Uehara [sup.3], Makoto Takatori [sup.4], Ken Yamaura [sup.5] Author Affiliations: (1) grid.411248.a, 0000 0004 0404 8415, Department of Anesthesiology [...]

Nitric oxide (NO) inhalation improves pulmonary hemodynamics in participants with pulmonary arterial hypertension (PAH). Although it can reduce pulmonary vascular resistance (PVR) in PAH, its impact on the dynamic mechanics of pulmonary arteries and its potential difference between control and participants with PAH remain unclear. PA impedance provides a comprehensive description of PA mechanics. With an arterial model, PA impedance can be parameterized into peripheral pulmonary resistance (Rp), arterial compliance (Cp), characteristic impedance of the proximal arteries (Zc), and transmission time from the main PA to the reflection site. This study investigated the effects of inhaled NO on PA impedance and its associated parameters in control and monocrotaline-induced pulmonary arterial hypertension (MCT-PAH) male rats (6/group). Measurements were obtained at baseline and during NO inhalation at 40 and 80 ppm. In both groups, NO inhalation decreased PVR and increased the left atrial pressure. Notably, its impact on PA impedance was frequency dependent, as revealed by reduced PA impedance modulus in the low-frequency range below 10 Hz, with little effect on the high-frequency range. Furthermore, NO inhalation attenuated Rp, increased Cp, and prolonged transmission time without affecting Zc. It reduced Rp more pronouncedly in MCT-PAH rats, whereas it increased Cp and delayed transmission time more effectively in control rats. In conclusion, the therapeutic effects of inhaled NO on PA impedance were frequency dependent and may differ between the control and MCT-PAH groups, suggesting that the effect on the mechanics differs depending on the pathological state. NEW & NOTEWORTHY: Nitric oxide inhalation decreased pulmonary arterial impedance in the low-frequency range (<10 Hz) with little impact on the high-frequency range. It reduced peripheral pulmonary resistance more pronouncedly in pulmonary hypertension rats, whereas it increased arterial compliance and transmission time in control rats. Its effect on the mechanics of the pulmonary arteries may differ depending on the pathological status. [ABSTRACT FROM AUTHOR]

Objectives: Effective treatments for vocal fold fibrosis remain elusive. Tamoxifen (TAM) is a selective estrogen receptor modulator and was recently reported to have antifibrotic actions. We hypothesized that TAM inhibits vocal fold fibrosis via altered transforming growth factor beta 1 (TGF‐β1) signaling. Both in vitro and in vivo approaches were employed to address this hypothesis. Methods: In vitro, vocal fold fibroblasts were treated with TAM (10−8 or 10−9 M) ± TGF‐β1 (10 ng/ml) to quantify cell proliferation. The effects of TAM on genes related to fibrosis were quantified via quantitative real‐time polymerase chain reaction. In vivo, rat vocal folds were unilaterally injured, and TAM was administered by oral gavage from pre‐injury day 5 to post‐injury day 7. The rats were randomized into two groups: 0 mg/kg/day (sham) and 50 mg/kg/day (TAM). Histological changes were examined on day 56 to assess tissue architecture. Results: TAM (10−8 M) did not affect Smad3, Smad7, Acta2, or genes related to extracellular matrix metabolism. TAM (10−8 or 10−9 M) + TGF‐β1, however, significantly increased Smad7 and Has3 expression and decreased Col1a1 and Acta2 expression compared to TGF‐β1 alone. In vivo, TAM significantly increased lamina propria area, hyaluronic acid concentration, and reduced collagen deposition compared to sham treatment. Conclusions: TAM has antifibrotic potential via the regulation of TGF‐β1/Smad signaling in vocal fold injury. These findings provide foundational data to develop innovative therapeutic options for vocal fold fibrosis. Level of Evidence: NA Laryngoscope, 133:2248–2254, 2023 [ABSTRACT FROM AUTHOR]

Objectives/Hypothesis: Vocal fold (VF) scar and sulcus cause severe vocal problems, but optimal methods have not been established. Total replacement of the mucosa is required particularly for cases in which the whole lamina propria is occupied by severe fibrosis and vibratory function is totally lost. The amniotic membrane (AM) has been proven to have regenerative potential, as it contains stem cells and growth factors. The current study investigated the biocompatibility and effects of AM for regeneration of the VF mucosa. Study Design: In vitro and in vivo studies. Methods: Vocal fold fibroblasts (VFFs) from 13 Sprague–Dawley rats were seeded on AM and subjected to histology and immunohistochemistry, and gene expressions in the VFFs on AM were examined in in vitro study. Twelve New Zealand White rabbits were used in in vivo study. VFs were stripped down and were reconstructed with AM. The regenerative effects were examined 3 months later by histological examination. Results: In vitro study indicated VFFs survived on AM and stained positively for Ki67, vimentin, and fibronectin. Gene expressions of Has1, Has2, and Hgf were significantly increased in the VFFs on AM compared with the other groups. The in vivo study indicated AM‐transplanted VFs showed a significantly higher density of hyaluronic acid and lower density of collagen compared with sham VFs. Conclusions: The current preliminary study suggests biocompatibility and possible regenerative effects of AM for VFs. Level of Evidence: NA Laryngoscope, 132:2017–2025, 2022 [ABSTRACT FROM AUTHOR]