Prevalencia de enfermedad pulmonar obstructiva crónica en las Islas Canarias

Introduction

The prevalence of chronic obstructive pulmonary disease (COPD) varies significantly among the different geographical areas reported. In Spain, two epidemiological studies have shown a prevalence of 9-10% in the population aged over 40. However, neither of these studies included the Canary Islands, which are of interest due to their climatic conditions and high incidence of smoking.

Materials and methods

A random group of 1,353 subjects aged between 40 and 70 years was selected from a sample population of 596,478 individuals. Participants completed a questionnaire and then performed spirometry with bronchodilator testing if obstruction was observed. COPD was diagnosed when the post-bronchodilator FEV₁/FVC ratio was less than 0.70.

Results

The prevalence of COPD was 7.3% (95% CI: 5.5-9.5) and was higher in males than in females (8.7% vs. 6.3%, P = .134). The incidence of smoking was 29.4% (95% CI: 25.4-33.1) and was also higher in males than in females (35.1% vs 25.4%, P < .001). The prevalence of COPD stratified by severity of obstruction, according to the GOLD criteria, was 16% in group i, 69.9% in group ii, 10.4% in group iii and 3.3% in group iv. 71.6% of the subjects were underdiagnosed and 63.5% undertreated.

Conclusions

Despite having one of the highest rates of smoking in Spain, the prevalence of COPD in the Canary Islands is lower than in most of the Spanish regions studied.     

Distribución de fenotipos clínicos en pacientes con enfermedad pulmonar obstructiva crónica por humo de biomasa y por tabaco

Introduction

Exposure to biomass smoke is a risk factor for chronic obstructive pulmonary disease (COPD). It is unknown whether COPD caused by biomass smoke has different characteristics to COPD caused by tobacco smoke.

Objective

To determine clinical differences between these two types of the disease.

Methods

Retrospective observational study of 499 patients with a diagnosis of COPD due to biomass or tobacco smoke. The clinical variables of both groups were compared.

Results

There were 122 subjects (24.4%) in the biomass smoke group and 377 (75.5%) in the tobacco smoke group. In the tobacco group, the percentage of males was higher (91.2% vs 41.8%, P < .0001) and the age was lower (70.6 vs 76.2 years, P < .0001). Body mass index and FEV₁% values were higher in the biomass group (29.4 ± 5.7 vs 28.0 ± 5.1, P = .01, and 55.6 ± 15.6 vs 47.1 ± 17.1, P < .0001, respectively). The mixed COPD-asthma phenotype was more common in the biomass group (21.3% vs 5%, P < .0001), although this difference disappeared when corrected for gender. The emphysema phenotype was more common in the tobacco group (45.9% vs 31.9%, P = .009). The prevalence of the chronic bronchitis and exacerbator phenotypes, the comorbidity burden and the rate of hospital admissions were the same in both groups.

Conclusion

Differences were observed between COPD caused by biomass and COPD caused by tobacco smoke, although these may be attributed in part to uneven gender distribution between the groups.     

Enfermedad pulmonar obstructiva crónica en pacientes con tromboembolia de pulmón aguda sintomática

Background

The diagnosis of pulmonary embolism (PE) is often complicated by the presence of chronic obstructive pulmonary disease (COPD). Some studies have suggested that patients with PE and concomitant COPD have a worse prognosis than patients without COPD.

Patients and methods

Outpatients diagnosed with acute symptomatic PE at a university tertiary care hospital were prospectively included in the study. Clinical characteristics, time between onset of symptoms and diagnosis, and outcome were analyzed according to presence or absence of COPD. The primary endpoint was all-cause deaths at 3 months.

Results

Of 882 patients with a confirmed diagnosis of acute symptomatic PE, 8% (95% confidence interval [CI], 6%–9%) had COPD. Patients with COPD were significantly more likely to have a delay in diagnosis of more than 3 days and to have a low pretest probability of pulmonary embolism according to a standardized clinical score. The total number of deaths during 3 months of follow-up was 128 (14%; 95% CI, 12%–17%). Factors significantly associated with mortality from all causes were a history of cancer or immobilization, systolic blood pressure less than 100 mm Hg, and arterial oxyhemoglobin saturation less than 90%. COPD was significantly associated with PE-related death in the logistic regression analysis (relative risk, 2.2; 95% CI, 1.0–5.1).

Conclusions

Patients with COPD and PE more often have a lower pretest probability and a longer delay in diagnosis of PE. COPD is significantly associated with PE-related death in the 3 months following diagnosis.     

Prevalencia de anemia asociada a la enfermedad pulmonar obstructiva crónica. Estudio de las variables asociadas

Background

Anaemia is one of the extrapulmonary manifestations of chronic obstructive pulmonary disease (COPD). Its real prevalence, physiopathology and clinical repercussion are unknown. The objectives of our study were: to determine the prevalence of anaemia in patients with stable COPD not attributable to other causes and to establish the relationship of anaemia with clinical, prognostic and inflammatory markers with an important role in COPD.

Methods

The study included stable COPD patients with no other known causes of anaemia. The following tests were carried out: respiratory function tests; serum determination of erythropoietin and inflammatory markers: high sensitivity C-reactive protein (hs-CRP), fibrinogen, interleukin 6 (IL-6), interleukin 8 (IL-8) and tumour necrosis factor α (TNF-α). Body mass index (BMI), Charlson and BODE indices, the number of exacerbations in the previous year, dyspnoea and quality of life were also calculated.

Results

One hundred and thirty patients were included. Anaemia prevalence was 6.2%. Mean haemoglobin value in anaemic patients was 11.9 ± 0.95 g/dL. Patients with anaemia had a lower BMI (P = .03), higher Charlson index (P = .002), more elevated erythropoietin levels (P = .016), a tendency to present a lower FEV₁% value (P = .08) and significantly lower IL-6 values when compared to non-anaemic patients (P = .003).

Conclusions

In our series, the anaemia associated with COPD was less prevalent than that published in the literature to date, and was related to certain clinical and inflammatory markers.     

Efectividad de la vacunación antigripal para evitar el ingreso hospitalario por agudización de la enfermedad pulmonar obstructiva crónica

Introduction

The main objective was to determine the effectiveness of influenza vaccination in preventing hospitalization due to exacerbation of chronic obstructive pulmonary disease (COPD). One secondary objective was to estimate the prevalence of vaccination, and to describe the factors that were associated with being vaccinated.

Methods

A retrospective cohort study was conducted that included 1,323 patients diagnosed with COPD in the Health Centre of the Pla d’Urgell (Lleida, Spain). They were classified into two cohorts: cohort 1, patients vaccinated against seasonal influenza (campaign 2011/12), and cohort 2, non-vaccinated. The number of patients in both cohorts requiring hospital admission for exacerbation of the disease between the 12/01/2011 and the 03/15/2012 was quantified. Information about the variables of interest was recorded for each patient. A univariate and multivariate analysis was performed. The effectiveness of vaccination was calculated with the formula: E = (1 – OR) × 100. The ORs and their 95% confidence interval (95%CI) were determined by multivariate logistic regression models.

Results

Just over half (55.3%) of the patients had been vaccinated. Vaccinated patients were older and had more associated comorbidity. At the same time, they were less hospitalized (3.0% versus 8.9%; P = .001). The crude and adjusted effectiveness of influenza vaccination in this population subgroup was 68.4% (95%CI: 47.5-81.0) and 90.8 (95%CI: 96.8-88.2), respectively.

Conclusion

Influenza vaccination is effective in preventing hospitalization due to acute exacerbations in COPD patients. However, immunization coverage is not as high as desired. Designing programs to increase the rate of vaccination in this population would reduce the number of hospital admissions for COPD exacerbation.     

Ventilación mecánica no invasiva en una población anciana que ingresa en una unidad de monitorización respiratoria: causas,complicaciones y evolución al año de seguimiento

Objective

To determine the usefulness of non-invasive ventilation (NIV) in elderly patients (≥75) admitted to a respiratory monitoring unit (RMU) during hospitalization and one year later in comparison with the results from the younger age group (<75).

Material and methods

Ours is a prospective observational study carried out at the Hospital Universitario La Princesa (Madrid, Spain). We recruited all patients who were ≥75 years old and were admitted to our RMU during the period 2008-2009 with respiratory acidosis (pH <7.35 and PaCO₂ >45 mmHg) requiring NIV. We gathered data for basic variables as well as sociodemographics, history of previous pathologies, reason for hospitalization and severity, analysis upon admission and the evolution of blood gases at the start of NIV (within the first hour and after 24 hours), complications and evolution at the one-year follow-up.

Results

Mean age of the sample was 80.6 years. The Charlson index was 3.27. About half of the patients had some limitation for performing daily activities. The main reasons for admission were COPD exacerbation and heart failure. There were complications in 36% of the cases (11 renal failure and 6 atrial fibrillation). The survival rate at the one-year follow-up was 63.21%.

Conclusions

NIV is a good alternative in elderly patients admitted to the hospital with respiratory acidosis. We did not detect differences in mortality during admission between the two groups. The elderly patients were more frequently re-admitted than the younger group in the 6-12 months after hospital discharge. This could be due to their poorer functional state after hospitalization requiring NIV.     

Infradiagnóstico de la enfermedad pulmonar obstructiva crónica en mujeres: cuantificación del problema,determinantes y propuestas de acción

Introduction

The distribution of chronic obstructive pulmonary disease (COPD) in women, and its underdiagnosis and determinants in the general population, have not been well described. The EPI-SCAN study is an epidemiologic, observational study conducted at 11 Spanish centers on the general population aged 40 to 80.

Patients and method

This paper describes the rates and extrapolates the population burden from the 3,802 participants of the EPI-SCAN study.

Results

With 2,005 female and 1,797 male participants, there was a lower prevalence of COPD in women (5.7%; 95% CI, 4.7-6.7) than in men (15.1%; 95% CI, 13.5-16.8; P < .05). Among the 386 participants with COPD, 114 (29.5%) were women, who were younger, currently smoked less and had lower tobacco smoke exposure, while reporting a lower level of education (P < .05). As for the respiratory symptoms, there were no differences between sexes for cough, dyspnea or wheezing, but the women with COPD reported sputum less frequently (P < .05). There were no differences in the spirometric severity of COPD between women and men. Overall, 73% of the patients with a spirometric COPD criteria were underdiagnosed, and this percentage is unevenly distributed by sex, being 1.27 times more frequent in women (86.0%) than in men (67.6%) (P < .05). By extrapolating the rates of prevalence and underdiagnosis of COPD to the general population, we estimate that there are 628,102 Spanish women between the ages of 40 and 80 with COPD, 540,168 of whom still have not been diagnosed.

Conclusions

There is a greater underdiagnosis of COPD in women than in men in Spain.     

Clasificación de la gravedad de la enfermedad pulmonar obstructiva crónica según la nueva guía Iniciativa Global para la Enfermedad Obstructiva Crónica 2011: COPD Assessment Test versus modified Medical Research Council

Introduction

The GOLD 2011 revision proposes to stratify patients with chronic obstructive pulmonary disease (COPD) by measuring the impact of the disease using the modified Medical Research Council (mMRC) scale or COPD assessment test (CAT). Our aim was to determine whether both methods are equivalent.

Patients and methods

Observational study on a cohort of 283 patients diagnosed with COPD. We analyzed the demographic and lung function results. Patients were assessed by CAT and mMRC on the same day by the same interviewer, and divided into GOLD 2011 categories according to the result of the evaluation. The degree of concordance and Spearman correlation were determined. We used ANOVA on the clinical and functional variables of the four GOLD 2011 categories.

Results

Assessing the classification of patients according to the method used, an overall correlation ρ = 0.613 and a degree of concordance κ = 0.63 (moderate) were obtained. κ = 0.44 was obtained for the 152 patients in categories A and B (moderate-low), and 0.38 for the 131 patients in categories C and D (low). Differences were observed between categories in terms of functional parameters.

Conclusions

The classification of patients with COPD using the assessment proposed by GOLD 2011 varies according to the method used (CAT or mMRC); more than 25% of patients were reclassified into different categories, implying differences in the recommended therapeutic strategy. Longitudinal studies are needed to appraise which method better classifies patients, according to its prognostic ability.     

Gran altitud y prevalencia de la enfermedad pulmonar obstructiva crónica: ¿relación casual o causal?

Introduction

Studies on the relationship of chronic obstructive pulmonary disease (COPD) prevalence and altitude have reported contrasting results. The aim of this COPD case-finding study was to include a larger number of geographical sites to determine if there is an association between altitude and COPD prevalence.

Patients and methods

Individuals aged 40 or older with known COPD risk factors, whether symptomatic or not, were referred by primary-care physicians. After obtaining written informed consent, they were invited to answer a questionnaire and undergo pre- and post-bronchodilator spirometry.

Results

Subjects were recruited in 27 Mexican cities, within an altitude range from 1 to 2,680 m above sea level. We found a weak (–0.31; P < .0001) although significant negative correlation between altitude and COPD prevalence. The COPD rate for cities located ≤1,000 m was 32.7% vs 16.4% for cities located >1,000 m (P < .0001); the rate for cities located at ≤2,000 m was 22.7% vs 15.6% for those >2,000 m; in the multiple logistic regression analysis, older age, male sex, tobacco habit, pack-years of smoking, years of exposure to biomass smoke and city altitude over sea level were significantly associated with COPD prevalence.

Conclusions

Our data shows a significant inverse correlation between prevalence/severity of COPD and altitude.     

Utilización de glucosa en los músculos de pacientes con enfermedad pulmonar obstructiva crónica

Introduction

Muscle dysfunction is one of the most extensively studied manifestations of COPD. Metabolic changes in muscle are difficult to study in vivo, due to the lack of non-invasive techniques. Our aim was to evaluate metabolic activity simultaneously in various muscle groups in COPD patients.

Methods

Thirty-nine COPD patients and 21 controls with normal lung function, due to undergo computed axial and positron emission tomography for staging of localized lung lesions were included. After administration of 18-fluordeoxyglucose, images of 2 respiratory muscles (costal and crural diaphragm, and rectus abdominus) and 2 peripheral muscles (brachial biceps and quadriceps) were obtained, using the standard uptake value as the glucose metabolism index.

Results

Standard uptake value was higher in both portions of the diaphragm than in the other muscles of all subjects. Moreover, the crural diaphragm and rectus abdominus showed greater activity in COPD patients than in the controls (1.8 ± 0.7 vs 1.4 ± 0.8; and 0.78 ± 0.2 vs 0.58 ± 0.1; respectively, P < .05). A similar trend was observed with the quadriceps. In COPD patients, uptake in the two respiratory muscles and the quadriceps correlated directly with air trapping (r = 0.388, 0.427 and 0.361, respectively, P < .05).

Conclusions

There is greater glucose uptake and metabolism in the human diaphragm compared to other muscles when the subject is at rest. Increased glucose metabolism in the respiratory muscles (with a similar trend in their quadriceps) of COPD patients is confirmed quantitatively, and is directly related to the mechanical loads confronted.     

Nocardiosis pulmonar en pacientes con EPOC: características y factores pronósticos

Introduction

Pulmonary nocardiosis (PN) is a severe infection with a high morbidity and mortality that mainly affects immunocompromised patients. In recent years, an increase in PN cases has been detected among patients with chronic obstructive pulmonary disease (COPD). The factors that are associated with its presence and determine its prognosis remain unknown.

Methods

Retrospective study of COPD patients diagnosed with PN over the period from 1997-2009 at the Hospital de la Santa Creu i Sant Pau, in Barcelona (Spain). Demographic, clinical, microbiological and evolution data were evaluated in all cases

Results

Thirty patients were identified with PN and COPD. Mean age (standard deviation) was 76 (7) years and the mean FEV₁ was 40 (14)%. Chronic respiratory failure was observed in 56,7% patients and 51,7% had received systemic corticosteroid therapy previous to the PN diagnosis. The most common symptoms were cough and dyspnea (90%). Alveolar infiltrates were observed in 60% of the cases. The most frequently isolated Nocardia species was N. cyriacigeorgica (68%). The one-month mortality rate was 17%, while the one-year mortality rate was 33%. The factors associated with mortality within the first year included previous systemic corticosteroid treatment, less than three months of specific antibiotic therapy and active associated neoplasm.

Conclusions

PN affects patients with moderate-severe COPD and has high short- and mid-term mortality rates. Previous corticosteroid treatment, specific antibiotic therapy for less than 3 months and active neoplasia were factors associated with mortality.     

Documento de consenso sobre el fenotipo mixto EPOC-asma en la EPOC

Introduction

Although asthma and COPD are different pathologies, many patients share characteristics from both entities. These cases can have different evolutions and responses to treatment. Nevertheless, the evidence available is limited, and it is necessary to evaluate whether they represent a differential phenotype and provide recommendations about diagnosis and treatment, in addition to identifying possible gaps in our understanding of asthma and COPD.

Methods

A nation-wide consensus of experts in COPD in two stages: 1) during an initial meeting, the topics to be dealt with were established and a first draft of statements was elaborated with a structured «brainstorming» method; 2) consensus was reached with two rounds of e-mails, using a Likert-type scale.

Results

Consensus was reached about the existence of a differential clinical phenotype known as «Overlap Phenotype COPD-Asthma», whose diagnosis is made when 2 major criteria and 2 minor criteria are met. The major criteria include very positive bronchodilator test (increase in FEV₁ ≥ 15% and ≥ 400 ml), eosinophilia in sputum and personal history of asthma. Minor criteria include high total IgE, personal history of atopy and positive bronchodilator test (increase in FEV₁ ≥ 12% and ≥ 200 ml) on two or more occasions. The early use of individually-adjusted inhaled corticosteroids is recommended, and caution must be taken with their abrupt withdrawal. Meanwhile, in severe cases the use of triple therapy should be evaluated. Finally, there is an obvious lack of specific studies about the natural history and the treatment of these patients.

Conclusions

It is necessary to expand our knowledge about this phenotype in order to establish adequate guidelines and recommendations for its diagnosis and treatment.     

Comparación de la respiración con presión positiva intermitente y la presión espiratoria positiva temporal en pacientes con enfermedad pulmonar obstructiva crónica grave

Background

Results supporting the use and the effectiveness of positive expiratory, pressure devices in chronic obstructive pulmonary disease (COPD) patients are still controversial, We have tested the hypothesis that adding TPEP or IPPB to standard pharmacological therapy may provide additional clinical benefit over, pharmacological therapy only in patients with severe COPD.

Methods

Fourty-five patients were randomized in three groups: a group was treated; with IPPB,a group was treated with TPEP and a group with pharmacological; therapy alone (control group).Primary outcome measures included the measurement of scale or, questionnaire concerning dyspnea (MRC scale),dyspnea,cough, and, sputum (BCSS) and quality of life (COPD assessment test) (CAT). Secondary, outcome measures were respiratory function testing,arterial blood gas,analysis,and hematological examinations.

Results

Both patients in the IPPB group and in the TPEP group showed a significant, improvement in two of three tests (MRC,CAT) compared to the control, group.However,in the group comparison analysis for, the same variables between IPPB group and TPEP group we observed a, significant improvement in the IPPB group (P ≤ .05 for MRC and P ≤ .01 for, CAT).The difference of action of the two techniques are evident in the results of, pulmonary function testing: IPPB increases FVC, FEV1, and MIP; this reflects, its capacity to increase lung volume. Also TPEP increases FVC and FEV1 (less, than IPPB), but increases MEP, while decreasing total lung capacity and, residual volume.

Conclusions

The two techniques (IPPB and TPEP) improves significantly dyspnea; quality of; life tools and lung function in patients with severe COPD. IPPB demonstrated a greater effectiveness to improve dyspnea and quality of life tools (MRC, CAT) than TPEP.     

Asincronía e hiperinsuflación en pacientes con enfermedad pulmonar obstructiva crónica durante 2 tipos de ejercicio de las extremidades superiores

Introduction

Occurrence of dynamic hyperinflation during upper-limbs exercises in chronic obstructive pulmonary disease (COPD) patients it is not well established. We hypothesized that dynamic hyperinflation and thoracoabdominal asynchrony occurs in COPD patients accomplishing arms exercises. We assessed the occurrence and association of dynamic hyperinflation and thoracoabdominal asynchrony in COPD patients during the accomplishment of two arm exercises.

Patients and methods

This was a prospective study with 25 COPD patients. A maximal and a sub-maximal upper limbs exercise test with 50% load were performed with the diagonal technique and the arm cycle ergometer technique. Respiratory pattern, thoracoabdominal configuration and dynamic hyperinflation were assessed in the exercise tests.

Results

Thirty per cent and 60% of patients hyperinflated at the end of the sub-maximum exercise tests with the diagonal and cycle ergometer techniques, respectively. Thoracoabdominal asynchrony occurred in 80% and 100% of patients who hyperinflated with the diagonal and cycle ergometer techniques, respectively. For both exercises we found enhancement of pulmonary ventilation, dyspnea, central respiratory drive and shortening of expiratory time (P < .05). Upper-limbs exercises with the diagonal technique presented less number of patients with these alterations.

Conclusions

Dynamic pulmonary hyperinflation and thoracoabdominal asynchrony association occurred in both upper-limbs exercises; however, the diagonal technique developed less dynamic hyperinflation and thoracoabdominal asynchrony in COPD patients than the arm cycle ergometer.     

Prueba de marcha de 6 min y ejercicio máximo en cicloergómetro en la enfermedad pulmonar obstructiva crónica, ¿son sus demandas fisiológicas equivalentes?

Background and objectives

The physiological load imposed by the six minute walk test (SMWT) in chronic obstructive pulmonary disease (COPD) patients come from small studies where the influence of disease severity has not been assessed. The aim of the present study was to compare the SMWT with an incremental cardiopulmonary exercise test (CPET) in patients classified by disease severity according to FEV₁ (cutoff 50% predicted).

Patients and methods

Eighty-one COPD patients (53 with FEV₁ ≥50%) performed both tests on two consecutive days. Oxygen consumption (O₂), carbon dioxide production (CO₂), minute ventilation (_E), heart rate (HR) and pulse oximetry (SpO₂) were measured during SMWT and CPET using portable equipment. Dyspnea and leg fatigue were measured with the Borg scale.

Results

In both groups, walking speed was constant during the SMWT and O₂ showed a plateau after the 3rd minute. When comparing SMWT (6th min) and peak CPET, patients with FEV₁ ≥50% showed a greater O₂, but lower values of CO₂,V_E, HR, dyspnea, leg fatigue, and SpO₂ during walking. In contrast, in those with FEV₁ <50% predicted values were similar. Distance walked during the SMWT strongly correlated with O₂ at peak CPET (r=0.78; P=0.0001).

Conclusion

The SMWT is a constant load exercise in COPD patients, regardless of disease severity. It imposes high metabolic, ventilatory and cardiovascular requirements, which were closer to those of CPET in severe COPD. These findings may explain the close correlation between distance walked and peak CPET O₂.     

Evolución del uso de la ventilación mecánica no invasiva en enfermedad pulmonar obstructiva crónica en una región española, 1997-2010

Introduction

Noninvasive mechanical ventilation (NIV) appeared in the 1980s as an alternative to invasive mechanical ventilation (IMV) in patients with acute respiratory failure. We evaluated the introduction of NIV and the results in patients with acute exacerbation of chronic obstructive pulmonary disease in the Region of Murcia (Spain).

Subjects and methods

A retrospective observational study based on the minimum basic hospital discharge data of all patients hospitalised for this pathology in all public hospitals in the region between 1997 and 2010. We performed a time trend analysis on hospital attendance, the use of each ventilatory intervention and hospital mortality through joinpoint regression.

Results

We identified 30.027 hospital discharges. Joinpoint analysis: downward trend in attendance (annual percentage change [APC] = −3.4, 95% CI: − 4.8; −2.0, P <.05) and in the group without ventilatory intervention (APC = −4.2%, −5.6; −2.8, P <.05); upward trend in the use of NIV (APC = 16.4, 12.0; 20. 9, P <.05), and downward trend that was not statistically significant in IMV (APC = −4.5%, −10.3; 1.7). We observed an upward trend without statistical significance in overall mortality (APC = 0.5, −1.3; 2.4) and in the group without intervention (APC = 0.1, −1.6; 1.9); downward trend with statistical significance in the NIV group (APC = −7.1, −11.7; −2.2, P <.05) and not statistically significant in the IMV group (APC = −0,8, −6, 1; 4.8). The mean stay did not change substantially.

Conclusions

The introduction of NIV has reduced the group of patients not receiving assisted ventilation. No improvement in results was found in terms of mortality or length of stay.     

Uso precoz de la ventilación mecánica no invasiva en pacientes con insuficiencia respiratoria hipercápnica aguda ingresados en una sala de neumología: estudio prospectivo

Background

In recent years, the optimal location for noninvasive mechanical ventilation (NIMV) has been a matter of debate. Our aim was to detect the effectiveness of NIMV in acute hypercapnic respiratory failure (AHRF) in respiratory ward and factors associated with failure.

Methods

69 patients treated with NIMV in respiratory ward were prospectively evaluated. The success of NIMV was defined as absence of need for intensive care unit (ICU) transfer with patient's dishcarge from hospital (group 1), failure of NIMV was defined as need for ICU transfer (group 2).

Results

The mean age was significantly higher in group 2. The cause of respiratory failure was COPD in 51 patients, obesity-hypoventilation syndrome in 14 and kyphoscoliosis in 4 patients. NIMV was successful in 55 patients and unsuccessful in 14. There was no significant difference between the two groups for pretreatment pH, PaCO₂ and PaO₂/FiO₂. After 1 h and 3 h of NIMV there was significant improvement in group 1. After 3 h of NIMV, in group 1 respiratory rate was significantly decreased. The pretreatment APACHE II score, respiratory rate, frequency of pneumoniae, associated complication and comorbid disease was significantly higher in group 2. The success rate was higher in patients with good compliance to NIMV.

Conclusion

NIMV can be succesfully applied in patients with AHRF in respiratory ward. The associated factors with NIMV failure are absence of early improvement in blood gases and respiratory rate, bad compliance to NIMV, older age, presence of associated complication, comorbid disease, pneumonia and high baseline respiratory rate.     

Variabilidad circadiana de la oximetría de pulso en niños sanos menores de 7 años

Background

Peripheral oxygen saturation (SpO₂) measured by pulse oximetry is widely used in clinical practice, but its fluctuations over the course of the 24 h of a day have not been explored at length. Recently, we reported that children hospitalized due to non-cardiopulmonary causes had a circadian variation in SpO₂. This finding needed to be corroborated in healthy children, which is the objective of the present study.

Patients and methods

Healthy children residing in a state foster home were studied with pulse oximetry every 2 h for 24 h.

Results

Eighty two children were included in the study, ranging in age from one month to 6.5 years (average ± standard error of 3.06 ± 0.16 years), with a weight-for-length/height percentile of 65.5 ± 2.9. In 65 (79.3%) children, the SpO₂ levels followed a sinusoidal curve suggesting circadian rhythm. The total group of sinusoidal curves in this population had a mesor of 95.10 ± 0.08% SpO₂, period of 21.05 ± 0.54 h (in 53.8% of these children, the period was between 20 and 28 h). The maximum SpO₂ was reached at 3:14 PM ± 16 min, and the minimum at 5:16 AM ± 48 min. When the 24 h were divided into four periods, it was demonstrated that the highest SpO₂ levels were reached between 2 PM and 8 PM.

Conclusions

In this population of clinically healthy children, there was a circadian variation in pulse oximetry, with maximum values in the late afternoon and minimal values in the early morning.     

Insuficiencia respiratoria hipercápnica aguda en pacientes con apneas del sueño

Introduction

Acute hypercapnic respiratory failure (AHRF) is a serious condition observed in some patients with sleep apnea-hypopnea syndrome (SAHS). The objective of the present study was to study the clinical characteristics of SAHS patients who develop AHRF and their prognosis.

Patients and method

A total of 70 consecutive SAHS patients who survived an AHRF episode and 70 SAHS patients paired by age with no previous history of AHRF were prospectively studied and followed up for 3 years.

Results

The deterioration of lung function due to obesity or concomitant chronic obstructive pulmonary diseases (COPD) was common in SAHS patients with AHRF. In the multivariate analysis, the risk factors associated with AHRF were baseline PaO_2, the theoretical percentage value of the forced vital capacity, alcohol consumption, and benzodiazepines. The mortality during follow up was higher among patients who had AHRF than in the control group. The main cause of death was respiratory, and the coexistence of COPD was identified as a mortality risk factor.

Conclusions

The development of AHRF in SAHS patients is associated with a deterioration in lung function and with alcohol and benzodiazepine consumption. The patients had a higher mortality after the AHRF episode, mainly a respiratory cause. New studies are required that evaluate the different available therapeutic options in these patients.     

Pronóstico tras una agudización grave de la EPOC tratada con ventilación mecánica no invasiva

Introduction

Patients with chronic obstructive pulmonary disease (COPD) who survived an acute exacerbation with acute respiratory failure that required non-invasive mechanical ventilation (NIMV) are a group with a poor medium-term prognosis.

Objective

To identify re-admission and mortality rates within one year from discharge and to analyse factors associated with both events in a consecutive series of COPD patients treated with NIMV.

Methods

A cohort of 93 COPD patients who survived an acute exacerbation and who required NIMV was followed up after discharge. Re-admissions due to respiratory causes and survival were measured and the outcomes were analysed against possible factors associated to such events using multivariate Cox proportional risk regression analysis.

Results

Over the year following discharge, 61 patients (66%) had to be re-admitted into hospital due to respiratory complications. Upon multivariate analysis, a low FEV₁ value in stable phase and a high average length of stay were associated independently with a high risk of hospital readmission. The probability of survival at 1 year was 0.695. Age, PaCO₂ prior to initiation of NIMV and the number of hospitalisation days in the previous year were associated independently with a high mortality risk.

Conclusions

This group of COPD patients has a high mortality rate and need for re-hospitalisation in the ensuing year following discharge. The variables relating to the severity of the baseline disease and the actual exacerbation have been shown to be associated with these events, and could be applied to this subgroup of patients in specific follow-up programs.