Clinical characteristics and outcomes of patients with obstructive sleep apnoea requiring intensive care.

We reviewed the clinical characteristics, required intervention and short- and long-term outcomes in obstructive sleep apnoea (OSA) patients requiring intensive care. A retrospective, single-centre, observational cohort study was undertaken in a multidisciplinary teaching medical and surgical intensive care unit. Adult patients with OSA (apnoea-hypopnoea index of 5 or higher) requiring intensive care from January 2000 to January 2005 were included. Thirty-seven OSA patients (age: 58 +/- 14 years, male:female 27:10) were admitted due to respiratory (n=12, 32%), cerebrovascular (n=8, 22%), cardiovascular (n=16, 43%) and infectious events (n=1, 2.7%). Comparing the clinical features, polysomnographic data and outcome among these groups, we found that OSA patients admitted due to respiratory events had significantly higher Acute Physiology and Chronic Health Evaluation II scores, lower arterial blood gas pH, higher PaCO2, a higher incidence of respiratory failure (92%) and required non-invasive ventilation after extubation (73%), and higher intensive care unit readmission rates than patients admitted due to cerebrovascular events and cardiovascular events (P < 0.05). No difference was found in the in-hospital and long-term mortality rate. The most common reason for intensive care unit admission in critically ill OSA patients was a cardiovascular event, followed by respiratory and cerebrovascular events. The baseline polysomnographic data of the OSA patients were not correlated with their clinical features and outcomes in the intensive care unit. A more complicated clinical course and higher intensive care unit readmission rate were encountered in OSA patients admitted due to respiratory events. Further studies would be required to evaluate the efficacy of non-invasive ventilation for facilitation of extubation in OSA patients presenting with hypercapnic respiratory failure.

Oxidative stress in nonallergic nasal polyps associated with bronchial hyperresponsiveness.

BACKGROUND: Nasal polyposis (NP) is a chronic inflammatory disease of upper airway with unknown etiology. NP is frequently associated with asthma; the interaction between these comorbidities remains interesting. Oxidative stress has been implicated in the pathophysiology of NP and asthma. The aim of this study is to investigate the significance of oxidative stress in sinonasal microenvironments by evaluating its association with clinopathological parameters and its impacts on the pathogenesis of bronchial hyperresponsiveness (BHR) in NP. METHODS: Polyp biopsy specimens were obtained from 20 nonallergic patients; control mucosas were obtained from 20 volunteers. The levels of free radicals in the tissues and in blood were determined by a sensitive chemiluminescence (CL) method. NP patients were substratified into three subgroups, NP without BHR, NP with asymptomatic BHR, and NP with BHR and asthma by the results of provocative testing. Four histological characteristics of NP, inflammatory cells, eosinophil infiltration, edema and fibrosis were estimated and applied to correlate with the tissue-CL. RESULTS: The mean CL level in polyp-tissues, but not in blood, was higher than in the control specimens. In NP patients, tissue-CL was associated with endoscopy score; high tissue-CL levels were positively correlated with the abundance of inflammatory cells and eosinophils. Tissue-CL and endoscopy score were associated with BHR/asthma phenotype. CONCLUSION: These results suggest an important role for oxidative stress in the pathophysiology of NP and a causal relation between oxidative stress and inflammatory cells, especially the eosinophils. Free radical levels in polyp-tissues associated with NP severity and with BHR/asthma phenotype in nonallergic NP patients.

A pilot trial of quantitative Tc-99m HMPAO and Ga-67 citrate lung scans to detect pulmonary vascular endothelial damage and lung inflammation in patients of collagen vascular diseases with active diffuse infiltrative lung disease.

Diffuse infiltrative lung disease (ILD) includes a heterogeneous group of disorders predominantly affecting lung parenchyma and sparing the airway. To assess the degree of pulmonary vascular endothelial damage in active ILD, lung/liver uptake ratios (L/L ratio) on technetium-99m hexamethylpropylene amine oxime (Tc-99m HMPAO) lung scan were determined in 30 patients with active ILD. Meanwhile, the gallium-67 citrate (Ga-67) uptake index (GUI) on Ga-67 lung scan was used to evaluate the severity of lung inflammation in active ILD. In this study, high-resolution CT (HRCT) was used to evaluate disease activity in ILD. The results show statistically significant differences between normal controls and patients with active ILD as shown in L/L ratios and GUI. However, when the patients were divided into two groups of 15 patients with normal chest X-ray findings and 15 with abnormal X-ray findings, there was no significant difference in those parameters. In addition, there was no statistically significant difference between the groups in HRCT scoring. No good correlation between the degree of pulmonary vascular endothelial damage and the severity of lung inflammation was found. In addition, there were no good correlations between HRCT scoring vs GUI and HRCT vs L/L ratio in different study subgroups. In conclusion, L/L ratios on Tc-99m HMPAO and GUI on Ga-67 lung scans differ from chest X-ray findings and have the potential to detect the degree of pulmonary vascular endothelial damage and severity of lung inflammation in active IDL. However, the relationships between HRCT scoring, GUI, and L/L ratio in patients with collagen vascular diseases and active ILD are not significant.

Increased lung uptake of technetium-99m hexamethylpropylene amine oxime in diffuse infiltrative lung disease.

BACKGROUND: Diffuse infiltrative lung disease (ILD) is a heterogeneous group of disorders which predominantly affect the lung parenchyma and spare the airway. OBJECTIVE: To assess pulmonary vascular endothelium damage in ILD, the lung uptake of technetium-99m hexamethylpropylene amine oxime (99mTc-HMPAO) was determined. METHODS: In 20 ILD patients and 25 controls without ILD, the lung uptake of 99mTc-HMPAO was measured. Anterior lung imaging, including a large part of the liver, was made 10 min after intravenous injection of 20-25 mCi of 99mTc-HMPAO. Regions of interest covered the liver and lung to calculate the lung/liver uptake ratios. The 20 ILD patients included 10 patients with clinically manifest pulmonary disease (group 1) and 10 asymptomatic patients (group 2). All of the study subjects had normal pulmonary function test results. RESULTS: The mean lung/liver uptake ratio in the 25 controls without ILD (0.36 +/- 0.10) was significantly lower than that in the 20 ILD patients (0.97 +/- 0.61). In addition, the mean lung/liver uptake ratio in the 10 ILD patients with clinically manifest pulmonary disease (1.45 +/- 0.51) was higher than that of the other 10 asymptomatic ILD patients (0.49 +/- 0.09). CONCLUSIONS: Our results indicated that determining the lung/liver uptake ratio on 99mTc-HMPAO lung imaging should be an objective method to assess subclinical pulmonary damage in ILD patients.

Hyperbaric oxygen as an adjunctive treatment for descending necrotizing mediastinitis: a case report.

Descending necrotizing mediastinitis is a rare but serious complication of oropharyngeal and deep neck infection which spreads down to the mediastinum via the cervical-facial planes. Its mortality rate remains high even with aggressive surgical drainage and appropriate antibiotics. Here, a case of descending necrotizing mediastinitis secondary to peritonsillar abscess is reported. It was successfully treated with hyperbaric oxygen and antibiotics followed by surgical drainage. Based on this report, hyperbaric oxygen therapy might be of great value as an adjunctive management to control this fatal infection.