Impaired Secretion Clearance Research Articles

Comparison between continuous thoracic epidural block and continuous thoracic paravertebral block in the management of thoracic trauma

BackgroundPostoperative pain is thought to be the single most important factor leading to ineffective ventilation and impaired secretion clearance after thoracic trauma. Effective pain relief can be provided by thoracic epidural analgesia but may have side effects or contraindications. Paravertebral block is an effective alternative method without the side effects of a thoracic epidural. We did this study to compare efficacy of thoracic epidural and paravertebral block in providing analgesia to thoracic trauma patients. MethodsAfter ethical clearance, 50 patients who had thoracic trauma were randomized into two groups. One was a thoracic epidural group (25), and second was a paravertebral group (25). Both groups received 10ml of bolus of plain 0.125% bupivacaine and a continuous infusion of 0.25% bupivacaine at the rate of 0.1ml/kg/h for 24h. Assessment of pain, hemodynamic parameters, and spirometric measurements of pulmonary function were done before and after procedure. Visual analog scale (VAS) scores were accepted as main outcome of the study and taken for power analysis. ResultsThere was significant decrease in postoperative pain in both the groups as measured by VAS score. However, the degree of pain relief between the groups was comparable. There was a significant improvement in pulmonary function tests in both the groups post-procedure. The change in amount of inflammatory markers between both the groups was not significantly different. ConclusionParavertebral block for analgesia is comparable to thoracic epidural in thoracic trauma patients and is associated with fewer side effects.

Airway Stenting and Tracheobronchoplasty Improve Respiratory Symptoms in Mounier-Kuhn Syndrome

Mounier-Kuhn syndrome (MKS) is a condition characterized by tracheobronchomegaly resulting from the loss or atrophy of musculoelastic fibers within the airway wall. Concomitant tracheobronchomalacia is seen in most patients with MKS, often leading to significant respiratory compromise due to bronchiectasis, increased dead space, and impaired secretion clearance. We report a series of 12 patients with MKS and tracheobronchomalacia who were evaluated at our institution for significant respiratory problems. Stent trials were conducted in 10 patients, with seven proceeding to operative tracheobronchoplasty (TBP) and one continuing with long-term stent placement. One patient underwent TBP without prior stent placement. Of the remaining three patients, two had no improvement with trials of stent placement, and a stent could not be placed in the third because of a large tracheal diameter. Compared with baseline values, clinically significant improvements in health-related quality-of-life measures and pulmonary function testing were seen in patients who underwent central airway stabilization (n = 9). Complications of both stent placement and TBP were generally mild. However, one death was reported in the surgical group secondary to an exacerbation of preexisting interstitial pneumonia. An aggressive approach that targets central airway stabilization may improve outcomes for patients with MKS. ClinicalTrials.gov; No.: NCT00550602; URL: www.clinicaltrials.gov.

Species differences in the physical and transport properties of airway secretions.

The clearance of airway secretions is vital in protecting the mammalian lung from pollution and infection. Diverse animal models have been used to study lung diseases associated with impaired secretion clearance. The extrapolation of data from animal models to humans is based on the assumption that there are structural and functional similarities in the airway epithelium and secretions. This manuscript reviews regulation of mucus secretion as well as the physical and transport properties of respiratory mucus. As tracheal size increases, the rigidity of airway secretions decreases, and rigidity is inversely correlated with mucociliary transportability. These differences are placed in the context of previously reported species and regional differences in transepithelial potential difference and the tracheobronchial epithelial cell population. Tracheal mucus transport velocity varies with the species studied and has been shown to positively correlate with tracheal surface area. A progressive increase in the rate of mucus transport from the small to the large airways has also been reported. The reduction in mucus rigidity from small to large airways could be one of the mechanisms responsible for velocity gradients, which facilitate mucociliary transport. Because airway dimensions, rather than anatomic level of the airway, may better predict epithelial secretory response, studies to assess the physiologic responses in human airways require the use of an animal model with a similar-sized airway.