Allon Raviv, Bhardwaj Saurabh, Sznitman Josué, Shoffel-Havakuk Hagit, Pinhas Sapir, Zloczower Elchanan, Shapira-Galitz Yael, Lahav Yonatan
Department of Otolaryngology, Head and Neck Surgery, Kaplan Medical Center, Rehovot 76100, Israel.
Faculty of Medicine, Hebrew University of Jerusalem, Rehovot 76100, Israel.
Pharmaceutics. 2023 Mar 10;15(3):903. doi: 10.3390/pharmaceutics15030903.
Subglottic stenosis represents a challenging clinical condition in otolaryngology. Although patients often experience improvement following endoscopic surgery, recurrence rates remain high. Pursuing measures to maintain surgical results and prevent recurrence is thus necessary. Steroids therapy is considered effective in preventing restenosis. Currently, however, the ability of trans-oral steroid inhalation to reach and affect the stenotic subglottic area in a tracheotomized patient is largely negligible. In the present study, we describe a novel trans-tracheostomal retrograde inhalation technique to increase corticosteroid deposition in the subglottic area. We detail our preliminary clinical outcomes in four patients treated with trans-tracheostomal corticosteroid inhalation via a metered dose inhaler (MDI) following surgery. Concurrently, we leverage computational fluid-particle dynamics (CFPD) simulations in an extra-thoracic 3D airway model to gain insight on possible advantages of such a technique over traditional trans-oral inhalation in augmenting aerosol deposition in the stenotic subglottic region. Our numerical simulations show that for an arbitrary inhaled dose (aerosols spanning 1-12 µm), the deposition (mass) fraction in the subglottis is over 30 times higher in the retrograde trans-tracheostomal technique compared to the trans-oral inhalation technique (3.63% vs. 0.11%). Importantly, while a major portion of inhaled aerosols (66.43%) in the trans-oral inhalation maneuver are transported distally past the trachea, the vast majority of aerosols (85.10%) exit through the mouth during trans-tracheostomal inhalation, thereby avoiding undesired deposition in the broader lungs. Overall, the proposed trans-tracheostomal retrograde inhalation technique increases aerosol deposition rates in the subglottis with minor lower-airway deposition compared to the trans-oral inhalation technique. This novel technique could play an important role in preventing restenosis of the subglottis.
声门下狭窄是耳鼻喉科中一种具有挑战性的临床病症。尽管患者在内镜手术后常有所改善，但复发率仍然很高。因此，采取措施维持手术效果并预防复发是必要的。类固醇疗法被认为对预防再狭窄有效。然而，目前经口吸入类固醇到达并影响气管切开患者声门下狭窄区域的能力在很大程度上可以忽略不计。在本研究中，我们描述了一种新型的经气管造口逆行吸入技术，以增加皮质类固醇在声门下区域的沉积。我们详细介绍了4例患者在手术后通过定量吸入器（MDI）经气管造口吸入皮质类固醇的初步临床结果。同时，我们利用体外三维气道模型中的计算流体-颗粒动力学（CFPD）模拟，以深入了解这种技术相对于传统经口吸入在增加狭窄声门下区域气溶胶沉积方面可能具有的优势。我们的数值模拟表明，对于任意吸入剂量（粒径范围为1-12 µm的气溶胶），与经口吸入技术相比，经气管造口逆行技术在声门下的沉积（质量）分数高出30倍以上（3.63%对0.11%）。重要的是，经口吸入操作中大部分吸入的气溶胶（66.43%）向远端输送经过气管，而在经气管造口吸入过程中，绝大多数气溶胶（85.10%）通过口腔排出，从而避免在更广泛的肺部产生不必要的沉积。总体而言，与经口吸入技术相比，所提出的经气管造口逆行吸入技术提高了声门下的气溶胶沉积率，同时减少了下呼吸道沉积。这种新技术可能在预防声门下再狭窄方面发挥重要作用。
