Smallest detectable change in volume differs between mass flow sensor and pneumotachograph

<p>Abstract</p> <p>Background</p> <p>To assess a pulmonary function change over time the mass flow sensor and the pneumotachograph are widely used in commercially available instruments. However, the smallest detectable change for both devices has never been compared. Therefore, the aim of this study is to determine the smallest detectable change in vital capacity (VC) and single-breath diffusion parameters measured by mass flow sensor and or pneumotachograph.</p> <p>Method</p> <p>In 28 healthy pulmonary function technicians VC, transfer factor for carbon monoxide (DLCO) and alveolar volume (VA) was repeatedly (10×) measured. The smallest detectable change was calculated by 1.96 x Standard Error of Measurement ×√2.</p> <p>Findings</p> <p>The mean (range) of the smallest detectable change measured by mass flow sensor and pneumotachograph respectively, were for VC (in Liter): 0.53 (0.46-0.65); 0.25 (0.17-0.36) (<it>p </it>= 0.04), DLCO (in mmol*kPa^-1*min^-1): 1.53 (1.26-1.7); 1.18 (0.84-1.39) (<it>p </it>= 0.07), VA (in Liter): 0.66. (0.53-0.82); 0.43 (0.34-0.53) (<it>p </it>= 0.04) and DLCO/VA (in mmol*kPa^-1*min^-1*L^-1): 0.22 (0.19-0.28); 0.19 (0.14-0.22) (<it>p </it>= 0.79).</p> <p>Conclusions</p> <p>Smallest detectable significant change in VC and VA as measured by pneumotachograph are smaller than by mass flow sensor. Therefore, the pneumotachograph is the preferred instrument to estimate lung volume change over time in individual patients.</p

GLUCONATO CÁLCICO 10% ENDOVENOSO: CUIDADOS DE LAS VÍAS DE INFUSIÓN EN PREMATUROS

Administration of 10% calcium gluconate in premature neonates and at due time is a habitual technique, which takes place in neonatal and neonatology ICUs as a complement of the parenteral nutrition administration and when dealing with certain pathologies. In spite of being a usual technique, it can lead to a series of complications which must be controlled. The creation of this protocol allows us to administrate 10% calcium gluconate in a safe way and to try to control the complications that can be associated with it such as extravasation and later calcification.La administración de gluconato cálcico al 10% en neonatos prematuros y a término es una técnica habitual que se desarrolla en las unidades de UCI neonatal y neonatología como complemento a la administración de nutriciones parenterales y ante algunas patologías. A pesar de ser una técnica habitual, puede llevar asociada una serie de complicaciones que debemos controlar. La creación de este protocolo nos permite administrar el gluconato cálcico 10% de forma segura y tratar de controlar las complicaciones que pueden asociarse como la extravasación y posterior calcificación

GASTROSQUISIS: PLAN DE CUIDADOS

We are presented with the case report of a newborn baby with gastroschisis, which is a congenital handicap characterized by the incomplete closure of the abdominal wall. The newborn was admitted to the neonatal ICU for stabilization and ulterior surgical closure of the defect. After surgery and during the hospital stay, an individualized caring plan based on the NANDA diagnosis was applied, interventions according to NIC classification, and expected results according to NOC classification. Thanks to the applied plan the newborn was discharged from hospital being suction fed and with the proper gastrointestinal transit.Se presenta el caso cl&iacute;nico de un reci&eacute;n nacido con gastrosquisis, que es un defecto cong&eacute;nito caracterizado por el cierre incompleto de la pared abdominal, que ingresa en la UCI Neonatal para su estabilizaci&oacute;n y posterior cierre quir&uacute;rgico del defecto. Tras la intervenci&oacute;n y durante su estancia se aplic&oacute; un plan de cuidados individualizado basado en los diagn&oacute;sticos NANDA, las intervenciones seg&uacute;n la clasificaci&oacute;n NIC y los resultados esperados seg&uacute;n la clasificaci&oacute;n NOC. Gracias al plan aplicado fue dado de alta tomando alimentaci&oacute;n por succi&oacute;n y con adecuado transito gastrointestinal

Genes and Gene Ontologies Common to Airflow Obstruction and Emphysema in the Lungs of Patients with COPD

Chronic obstructive pulmonary disease (COPD) is a major public health problem with increasing prevalence worldwide. The primary aim of this study was to identify genes and gene ontologies associated with COPD severity. Gene expression profiling was performed on total RNA extracted from lung tissue of 18 former smokers with COPD. Class comparison analysis on mild (n = 9, FEV1 80–110% predicted) and moderate (n = 9, FEV1 50–60% predicted) COPD patients identified 46 differentially expressed genes (p<0.01), of which 14 genes were technically confirmed by quantitative real-time-PCR. Biological replication in an independent test set of 58 lung samples confirmed the altered expression of ten genes with increasing COPD severity, with eight of these genes (NNMT, THBS1, HLA-DPB1, IGHD, ETS2, ELF1, PTGDS and CYRBD1) being differentially expressed by greater than 1.8 fold between mild and moderate COPD, identifying these as candidate determinants of COPD severity. These genes belonged to ontologies potentially implicated in COPD including angiogenesis, cell migration, proliferation and apoptosis. Our secondary aim was to identify gene ontologies common to airway obstruction, indicated by impaired FEV1 and KCO. Using gene ontology enrichment analysis we have identified relevant biological and molecular processes including regulation of cell-matrix adhesion, leukocyte activation, cell and substrate adhesion, cell adhesion, angiogenesis, cell activation that are enriched among genes involved in airflow obstruction. Exploring the functional significance of these genes and their gene ontologies will provide clues to molecular changes involved in severity of COPD, which could be developed as targets for therapy or biomarkers for early diagnosis

Lung diffusing capacity for nitric oxide and carbon monoxide in relation to morphological changes as assessed by computed tomography in patients with cystic fibrosis

Background Due to large-scale destruction, changes in membrane diffusion (Dm) may occur in cystic fibrosis (CF), in correspondence to alterations observed by computed tomography (CT). Dm can be easily quantified via the diffusing capacity for nitric oxide (DLNO), as opposed to the conventional diffusing capacity for carbon monoxide (DLCO). We thus studied the relationship between DLNO as well as DLCO and a CF-specific CT score in patients with stable CF. Methods Simultaneous single-breath determinations of DLNO and DLCO were performed in 21 CF patients (mean ± SD age 35 ± 9 y, FEV1 66 ± 28%pred). Patients also underwent spirometry and bodyplethysmography. CT scans were evaluated via the Brody score and rank correlations (rS) with z-scores of functional measures were computed. Results CT scores correlated best with DLNO (rS = -0.83; p < 0.001). Scores were also related to the volume-specific NO transfer coefficient (KNO; rS = -0.63; p < 0.01) and to DLCO (rS = -0.79; p < 0.001) but not KCO. Z-scores for DLNO were significantly lower than for DLCO (p < 0.001). Correlations with spirometric (e.g., FEV1, IVC) or bodyplethysmographic (e.g., SRaw, RV/TLC) indices were weaker than for DLNO or DLCO but most of them were also significant (p < 0.05 each). Conclusion In this cross sectional study in patients with CF, DLNO and DLCO reflected CT-morphological alterations of the lung better than other measures. Thus the combined diffusing capacity for NO and CO may play a future role for the non-invasive, functional assessment of structural alterations of the lung in CF

MRC chronic Dyspnea Scale: Relationships with cardiopulmonary exercise testing and 6-minute walk test in idiopathic pulmonary fibrosis patients: a prospective study

<p>Abstract</p> <p>Background</p> <p>Exertional dyspnea is the most prominent and disabling feature in idiopathic pulmonary fibrosis (IPF). The Medical Research Chronic (MRC) chronic dyspnea score as well as physiological measurements obtained during cardiopulmonary exercise testing (CPET) and the 6-minute walk test (6MWT) are shown to provide information on the severity and survival of disease.</p> <p>Methods</p> <p>We prospectively recruited IPF patients and examined the relationship between the MRC score and either CPET or 6MWT parameters known to reflect physiologic derangements limiting exercise capacity in IPF patients</p> <p>Results</p> <p>Twenty-five patients with IPF were included in the study. Significant correlations were found between the MRC score and the distance (r = -.781, p < 0.001), the SPO₂at the initiation and the end (r = -.542, p = 0.005 and r = -.713, p < 0.001 respectively) and the desaturation index (r = .634, p = 0.001) for the 6MWT; the MRC score and <it>V</it>O₂peak/kg (r = -.731, p < 0.001), SPO₂at peak exercise (r = -. 682, p < 0.001), VE/VCO₂slope (r = .731, p < 0.001), VE/VCO₂at AT (r = .630, p = 0.002) and the Borg scale at peak exercise (r = .50, p = 0.01) for the CPET. In multiple logistic regression analysis, the only variable independently related to the MRC is the distance walked at the 6MWT.</p> <p>Conclusion</p> <p>In this population of IPF patients a good correlation was found between the MRC chronic dyspnoea score and physiological parameters obtained during maximal and submaximal exercise testing known to reflect ventilatory impairment and exercise limitation as well as disease severity and survival. This finding is described for the first time in the literature in this group of patients as far as we know and could explain why a simple chronic dyspnea score provides reliable prognostic information on IPF.</p

Echocardiography may help detect pulmonary vasculopathy in the early stages of pulmonary artery hypertension associated with systemic sclerosis

<p>Abstract</p> <p>Background</p> <p>Pulmonary arterial hypertension (PAH) in patients with systemic sclerosis is associated with a poor prognosis, but this can be improved by early disease detection. Abnormal pulmonary and cardiac function can be detected early by means of echocardiography, whereas right heart catheterization is usually performed later.</p> <p>Objectives</p> <p>The purpose of this prospective study was to detect early the presence of pulmonary artery vasculopathy in patients with verified systemic sclerosis without significant pulmonary fibrosis, normal lung volumes and a mildly reduced lung diffusion capacity of carbon monoxide (DLCO).</p> <p>Methods</p> <p>Nineteen consecutive female NYHA class I-II patients with scleroderma and a PAPs of < 35 mm/Hg measured by echocardiography, were enrolled between September 2007 and September 2009. They had a mean age of 51 ± 13 years, body mass index of 25 ± 5 kg/m²). They all underwent complete Doppler echocardiography, CPET, a pulmonary ventilation test (carbon monoxide lung diffusion, DLCO), HRCT. To investigate PAH by means of complete resting Doppler echocardiography estimates of systolic pulmonary artery pressure (PAPs) derived from tr icuspid regurgitation, mean PAP derived from pulmonary regurgitation, pulmonary vessel resistance (PVR) derived from the acceleration time of the pulmonary outflow tract (ACTpo), and right ventricular function derived from tricuspid annular plane systolic excursion (TAPSE). Right heart catheterisation was conducted only, if pulmonary hypertension was suggested by echocardiography and an abnormal ventilator test.</p> <p>The data are given as mean values ± SD, unless otherwise stated. The correlations between the variables were analysed using Pearson's <it>r </it>coefficient, and the predictive value of the variables was calculated using linear regression analysis. A p value of > 0.05 was considered significant.</p> <p>Results</p> <p>Right heart catheterization detected PAH in 15/19 patients; mean PAP was 30.5 mm/Hg and RVP 3.6 UW. Coronary angiography of the patients aged more than 55 years showed some evidence of significant coronary artery disease. Echocardiography showed high systolic PAP values (46 ± 8 mmHg), whereas right ventricular function was normal (TAPSE 23 ± 3 mm), and in line with the NYHA class. ACTpo was reduced in the patients with a systolic PAP of < 46 mm/Hg (p > 0.001) and positively correlated with DLCO (p > 0.001) and the hemodynamic data.</p> <p>There was a good correlation between ACTpo and PVR (hemodynamic data) (r = -0615; p > 0.01).</p> <p>Conclusions</p> <p>Although they need to be confirmed by studies of larger series of patients, our findings suggest that, in comparison with hemodynamic data, non-invasive echocardiographic measurements are an excellent means of identifying early-stage PAH.</p

Ventilation-perfusion inequality in the human lung is not increased following no-decompression-stop hyperbaric exposure

Venous gas bubbles occur in recreational SCUBA divers in the absence of decompression sickness, forming venous gas emboli (VGE) which are trapped within pulmonary circulation and cleared by the lung without overt pathology. We hypothesized that asymptomatic VGE would transiently increase ventilation-perfusion mismatch due to their occlusive effects within the pulmonary circulation. Two sets of healthy volunteers (n = 11, n = 12) were recruited to test this hypothesis with a single recreational ocean dive or a baro-equivalent dry hyperbaric dive. Pulmonary studies (intrabreath VA/Q (iV/Q), alveolar dead space, and FVC) were conducted at baseline and repeat 1- and 24-h after the exposure. Contrary to our hypothesis VA/Q mismatch was decreased 1-h post-SCUBA dive (iV/Q slope 0.023 ± 0.008 ml−1 at baseline vs. 0.010 ± 0.005 NS), and was significantly reduced 24-h post-SCUBA dive (0.000 ± 0.005, p < 0.05), with improved VA/Q homogeneity inversely correlated to dive severity. No changes in VA/Q mismatch were observed after the chamber dive. Alveolar dead space decreased 24-h post-SCUBA dive (78 ± 10 ml at baseline vs. 56 ± 5, p < 0.05), but not 1-h post dive. FVC rose 1-h post-SCUBA dive (5.01 ± 0.18 l vs. 5.21 ± 0.26, p < 0.05), remained elevated 24-h post SCUBA dive (5.06 ± 0.2, p < 0.05), but was decreased 1-hr after the chamber dive (4.96 ± 0.31 L to 4.87 ± 0.32, p < 0.05). The degree of VA/Q mismatch in the lung was decreased following recreational ocean dives, and was unchanged following an equivalent air chamber dive, arguing against an impact of VGE on the pulmonary circulation