We delivered controlled radio frequency energy to the airways of anesthetized, ventilated dogs to examine the effect of this treatment on reducing airway narrowing caused by a known airway constrictor. The airways of 11 dogs were treated with a specially designed bronchial catheter in three of four lung regions. Treatments in each of the three treated lung regions were controlled to a different temperature (55, 65, and 75 degrees C); the untreated lung region served as a control. We measured airway responsiveness to local methacholine chloride (MCh) challenge before and after treatment and examined posttreatment histology to 3 yr. Treatments controlled to 65 degrees C as well as 75 degrees C persistently and significantly reduced airway responsiveness to local MCh challenge (P < or = 0.022). Airway responsiveness (mean percent decrease in airway diameter after MCh challenge) averaged from 6 mo to 3 yr posttreatment was 79 +/- 2.2% in control airways vs. 39 +/- 2.6% (P < or = 0.001) for airways treated at 65 degrees C, and 26 +/- 2.7% (P < or = 0.001) for airways treated at 75 degrees C. Treatment effects were confined to the airway wall and the immediate peribronchial region on histological examination. Airway responsiveness to local MCh challenge was inversely correlated to the extent of altered airway smooth muscle observed in histology (r = -0.54, P < 0.001). We conclude that the temperature-controlled application of radio frequency energy to the airways can reduce airway responsiveness to MCh for at least 3 yr in dogs by reducing airway smooth muscle contractility.

Download full-text PDF

Source
http://dx.doi.org/10.1152/japplphysiol.01282.2003DOI Listing

Publication Analysis

Top Keywords

airway responsiveness
20
mch challenge
16
responsiveness local
12
airway
11
radio frequency
8
frequency energy
8
energy airways
8
reducing airway
8
lung regions
8
local mch
8

Similar Publications

Background: Given the prevalence of cardiovascular disease, encountering difficult airways in this patient population is quite common. The challenge for anesthesiologists lies not only in establishing the airway but also in managing the hemodynamic instability caused by sympathetic activation during intubation. The purpose of this report is to describe the anesthetic experience of this patient with severe mitral and tricuspid regurgitation, atrial fibrillation with rapid ventricular response, and moderate pulmonary hypertension with an anticipated difficult airway.

View Article and Find Full Text PDF

Human epidermal growth factor receptor 2 (HER2, also known as ERBB2) signaling promotes cell growth and differentiation, and is overexpressed in several tumor types, including breast, gastric and colorectal cancer. HER2-targeted therapies have shown clinical activity against these tumor types, resulting in regulatory approvals. However, the efficacy of HER2 therapies in tumors with HER2 mutations has not been widely investigated.

View Article and Find Full Text PDF

Silibinin alleviates house dust mite induced allergic airway inflammation by inhibiting NLRC4 inflammasome and MMP-9 expression.

Biomed Pharmacother

January 2025

College of Veterinary Medicine and BK21 FOUR Program, Chonnam National University, 77 Yong-bong-ro, Buk-gu, Gwangju 61186, Republic of Korea. Electronic address:

Silibinin, a major compound of silymarin, has been reported to alleviate respiratory diseases including acute lung injury, asthma, chronic obstructive pulmonary disease, and pulmonary fibrosis through its antifibrotic, anti-inflammatory, and antioxidant properties. However, the specific mechanisms underlying its therapeutic effects, particularly in allergic asthma, are not fully understood. With the increasing prevalence and impact of allergic asthma, there is a need to elucidate the exact underlying mechanisms of its potential treatment effects.

View Article and Find Full Text PDF

Background: There is significant variability in airway management training among pulmonary and critical care medicine (PCCM) fellows.

Objective: To assess the airway management training of PCCM fellows, specifically evaluating the role of the institutional approach to intubations (anesthesia-predominant primary operators vs. PCCM-predominant) to the overall fellows' educational experience.

View Article and Find Full Text PDF

Study Objectives: Multilevel upper airway surgery is effective for some patients with obstructive sleep apnea (OSA), but prediction the response to surgery remains a challenge. The underlying endotypes of OSA include upper airway collapsibility, muscle compensation, loop gain, and the arousal threshold. This study aimed to explore the effect of surgery on polysomnography (PSG)-derived OSA endotypes and establish a surgical response prediction model.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!