P50 sensory gating in hypoxemic chronic obstructive pulmonary disease patients.

PURPOSE: Chronic obstructive pulmonary disease (COPD) is a condition characterized by progressive airway obstruction and recurrent attacks. Multisystem involvement with extrapulmonary manifestations has been seen in COPD patients. Numerous neurological involvement like cerebrovascular diseases, polyneuropathies, motor neuron diseases and cognitive impairement has been reported in COPD patients. Cognitive dysfunction is usually associated with hypoxia or hypercapnia in COPD patients. To our knowledge there is no study about sensory gating in COPD patients. We performed p50 test to COPD patients and we investigate sensory gating in COPD patients. PATIENTS AND METHODS: 25 male patients with COPD and 17 healthy male subjects for controls included to this study. The patients were diagnosed with COPD according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria. p50 amplitude and latency, percentage of P50 suppression, N100 amplitude and latency and the N100 suppression percentage of the COPD patients and controls presented were measured and compared. RESULTS: We found that the conditioning amplitudes (S1) did not differ between COPD patients and controls (p > 0.05) but (S2) amplitude was significantly increased in COPD patients (p < 0.05). COPD patients showed significantly lower P50 and N100 suppression percentage than controls (p < 0.05). CONCLUSIONS: COPD patients showed a disturbance cognitive function such as attention with p50 suppression rate decrease. P50 sensory gating test can be useful to analyze the pre-attention period of cognitive impairment in the early phase of COPD patients.

Long-term follow-up of chronic obstructive pulmonary disease patients on long-term oxygen treatment.

AIMS: Few studies exist on influence of long-term oxygen treatment (LTOT) on survival of chronic obstructive pulmonary disease (COPD) patients. This study was designed to determine whether LTOT improves survival or not in severely hypoxaemic COPD patients. MATERIALS: COPD patients prescribed oxygen concentrator were consecutively included. Patients' baseline characteristics were noted. During follow-up, patients were divided into three groups according to LTOT utilisation: (i) non-utilisers, (ii) intermittent utilisers (< 15 h/day) and (iii) true utilisers (≥ 15 h/day). Patients' status (live or death) and, if died, the date of death were checked throughout the study. The factors which might influence mortality during 5-year period were analysed. RESULTS: Two-hundred and twenty-eight patients completed the study. Of these patients, 55 were in Group 1, 112 were in Group 2 and 61 were in Group 3. Regarding the initial characteristics, there was not any significant difference between groups. Mean follow-up for whole group was 27.8 ± 18.5 months. Median survivals were similar between groups (19.5 ± 5.6, 32.5 ± 4.1 and 30.0 ± 5.7 months respectively) (p > 0.05). Compared with Group 1, survival was improved in Group 2 (p < 0.05) and there was a positive trend for Group 3 during first 2-year period. However, this improvement disappeared during further follow-up. Analysis of multiple factors which might influence mortality during 5-year period did not yield statistically significant parameter. DISCUSSION AND CONCLUSION: We found that, regarding survival, any kind of LTOT proved to be beneficial over no LTOT only in the first 2 years of follow-up, and that there was not any difference between intermittent and true LTOT utilisation.

The influence of severe obesity on non-invasive ventilation (NIV) strategies and responses in patients with acute hypercapnic respiratory failure attacks in the ICU.

BACKGROUND: Obesity rates are increasing in the general population and are also prevalent in intensive care units (ICUs). Patients are sometimes admitted to ICUs for hypercapnic respiratory failure or cor pulmonale, but more often, they are admitted for pneumonia, excessive daytime sleepiness, heart failure, chronic obstructive pulmonary disease (COPD), asthma attacks or pulmonary embolism, and hypercapnic respiratory failure is coincidentally noticed during this period. The optimal noninvasive mechanical ventilation strategy is often not used during ICU treatment. The aim of this study was to assess the differences between non-invasive ventilation (NIV) strategies and the outcomes of obese and non-obese patients with acute hypercapnic respiratory failure. METHODS: In this retrospective cohort study, 73 patients who were ventilated with a face mask were studied. Patients were divided into two groups: obese (BMI>35 kg/m2) and non-obese (BMI<35 kg/m2), and the differences between these two groups in necessary pressure, volume, mode, ventilator and time to reduce PaCO2 <50 mmHg were investigated. RESULTS: The mean age of the patients was 66 ± 14 years, and the mean admission APACHE II score was 18 ± 4. Forty-one (56%) of the patients were female. For the obese patients, the reason for ICU admission was more frequently pulmonary edema and less frequently pulmonary infections, which was significantly different (P=0.003 and 0.043, respectively) than the rates for the non-obese patients. While there was no significant difference across the groups between the ventilators, modes and inspiratory pressure levels, obese patients required higher end-expiratory pressure levels and more time to reduce their PaCO2 levels below 50 mmHg than non-obese patients. The lengths of NIV and ICU stay and intubation and the mortality rates were similar in both groups. CONCLUSION: These results suggest that improvement in hypercapnia in obese patients may require higher PEEP levels and longer times than that of non-obese patients during acute hypercapnic respiratory failure attack.

Venous thromboemboli and exacerbations of COPD.

The aim of the present study was to determine the prevalence of and risk factors for venous thromboembolism (VTE) in exacerbations of chronic obstructive pulmonary disease (COPD). COPD patients hospitalised with an exacerbation were included consecutively. Symptoms, signs and clinical, haematological and epidemiological parameters on admission were noted. All patients underwent computed tomographic angiography and ultrasonographic examination for deep vein thrombosis and pulmonary embolism (PE). Wells and Geneva scores were calculated. Patients were followed-up for 1 yr in order to determine mortality. Deep vein thrombosis and PE were detected in 14 and 18 patients, respectively. The prevalence of VTE was three times higher in patients with an exacerbation of unknown origin than in patients with an exacerbation of known origin (p = 0.016). Of patients with VTE, 20 (95%) had high D-dimer levels. The negative predictive value of D-dimer testing was 0.98. Although the moderate- and high-risk categories of both the Wells and Geneva methods covered all PE patients, the Wells method identified 49% less potential patients for PE investigation. Mortality at 1 yr was higher (61.9% versus 31.8%) in VTE patients (p = 0.013). VTE is a common problem in COPD patients hospitalised with an exacerbation, leading to high long-term mortality. D-dimer levels and the Wells criteria can be used to determine whether or not these patients are assessed for a thromboembolic event.

The role of nebulised budesonide in the treatment of exacerbations of COPD.

The present study was designed to evaluate the hypothesis that nebulised budesonide (NB) might be an alternative to systemic corticosteroids (SC) in the treatment of patients with exacerbations of chronic obstructive pulmonary disease (ECOPD). Patients hospitalised with ECOPD (n = 159) were randomised into three groups. Group 1 received only standard bronchodilator treatment (SBDT), group 2 received SC (40 mg prednisolone) plus SBDT, and group 3 received NB (1,500 microg q.i.d.) plus SBDT. Improvement during 10-day hospitalisation was compared with exacerbation and rehospitalisation rates after discharge. While mean+/-sd age was 64.1+/-8.9 yrs (female/male = 0.1), mean forced expiratory volume in one second (FEV(1)) at admission was found to be 37.2+/-12.2% predicted. Arterial blood gases and spirograms recovered faster in groups 2 and 3. While improvements in arterial oxygen tension (P(a,O(2))) and forced vital capacity (FVC) in group 2, and improvements in P(a,O(2)), FVC and FEV(1) in group 3, became significant at 24-h control, the first significant improvement in group 1 appeared in arterial oxygen saturation at 72-h control. The mean improvement of P(a,O(2)) after 10 days was 1.20 and 1.06 kPa (9 and 8 mmHg) higher in group 2 and 3, respectively, than in group 1. Blood glucose exhibited an upward trend only in group 2. The study demonstrates that nebulised budesonide may be an effective and safe alternative to systemic corticosteroids in the treatment of exacerbations of chronic obstructive pulmonary disease.

Factors affecting survival of hospitalised patients with COPD.

Factors determining in-hospital mortality and long-term survival of patients hospitalised with acute exacerbations of chronic obstructive pulmonary disease (AECOPD) are not precisely understood. The aim of the present study was to assess the parameters related to in-hospital mortality and long-term survival after hospitalisation of patients with AECOPD. Clinical and epidemiological parameters on admission in 205 consecutive patients hospitalised with AECOPD were prospectively assessed. Patients were followed-up for 3 yrs. Factors determining short- and long-term mortality were analysed. In total, 17 patients (8.3%) died in hospital. In-hospital mortality was significantly associated with lower arterial oxygen tension (P(a,O2)), higher carbon dioxide arterial tension, lower arterial oxygen saturation and longer hospital stay. The overall 6-month mortality rate was 24%, with 1-, 2- and 3-yr mortality rates of 33%, 39% and 49%, respectively. Cox regression analysis revealed that long-term mortality was associated with longer disease duration (relative risk (RR) = 1.158), lower albumin (RR = 0.411), lower P(a,O2) (RR = 0.871) and lower body mass index (RR = 0.830). When the model was run for the time elapsed since first hospitalisation, it also appeared as statistically significant (RR = 1.195). These findings show that patients hospitalised with acute exacerbations of chronic obstructive pulmonary disease have poor short- and long-term survival. Prediction of survival status may be enhanced by considering arterial oxygen tension, albumin, body mass index, disease duration and time elapsed since the first hospitalisation.