Chemical composition modulates the adverse effects of particles on the mucociliary epithelium

OBJECTIVE:We compared the adverse effects of two types of real ambient particles; i.e., total suspended particles from an electrostatic precipitator of a steel mill and fine air particles from an urban ambient particulate matter of 2.5 µm, on mucociliary clearance.METHOD:Mucociliary function was quantified by mucociliary transport, ciliary beating frequency and the amount of acid and neutral mucous in epithelial cells through morphometry of frog palate preparations. The palates were immersed in one of the following solutions: total suspended particles (0.1 mg/mL), particulate matter 2.5 µm 0.1 mg/mL (PM0.1) or 3.0 mg/mL (PM3.0) and amphibian Ringer’s solution (control). Particle chemical compositions were determined by X-ray fluorescence and gas chromatography/mass spectrometry.RESULTS:Exposure to total suspended particles and PM3.0 decreased mucociliary transport. Ciliary beating frequency was diminished by total suspended particles at all times during exposure, while particulate matter of 2.5 µm did not elicit changes. Particulate matter of 2.5 µm reduced epithelial mucous and epithelium thickness, while total suspended particles behaved similarly to the control group. Total suspended particles exhibited a predominance of Fe and no organic compounds, while the particulate matter 2.5 µm contained predominant amounts of S, Fe, Si and, to a lesser extent, Cu, Ni, V, Zn and organic compounds.CONCLUSION:Our results showed that different compositions of particles induced different airway epithelial responses, emphasizing that knowledge of their individual characteristics may help to establish policies aimed at controlling air pollution

Expression of acute phase cytokines, surfactant proteins, and epithelial apoptosis in small airways of human ARDS

Alguns estudos sugerem que as pequenas vias aéreas têm um papel importante na fisiopatologia da lesão pulmonar aguda/ síndrome do desconforto respiratório agudo (LPA/SDRA). O epitélio respiratório que reveste as vias aéreas é capaz de liberar mediadores inflamatórios e está relacionado ainda com a produção de surfactante nas vias aéreas. Até o presente momento, existem poucos estudos que avaliaram se estas funções do epitélio que reveste as pequenas vias aéreas encontram-se alteradas na SDRA. No presente estudo, nós mensuramos a expressão da proteína de surfactante (PS) A e PS-B, a expressão de citocinas inflamatórias interleucina (IL)-6 e IL-8, e um índice de apoptose do epitélio que reveste as pequenas vias aéreas de pacientes com SDRA que foram submetidos a autópsia e comparamos estes resultados com os de indivíduos controle. Foram incluídos no estudo pulmões de autópsia de 31 pacientes com SDRA (PaO2/FiO2200, 45±14 anos, 16 homens) e 11 controles (52±16 anos, 7 homens). A expressão de IL-6, IL-8, PS-A e PS-B no epitélio das pequenas vias aéreas (diâmetro2.0mm) foi verificada através de reações de imunohistoquímica e análise de imagem. O índice de apoptose epitelial das vias aéreas foi avaliado através do método de TUNEL e da expressão de FAS/FASL. Avaliou-se ainda a densidade de células inflamatórias positivas para IL-6 e IL-8 na parede das pequenas vias aéreas. As vias aéreas dos pacientes com SDRA apresentaram maior expressão epitelial de IL-8 (p=0,006) e maior densidade de células inflamatórias expressando IL-6 (p=0,004) e IL-8 (p<0,001) quando comparadas com o grupo controle. Não houve diferenças na expressão epitelial de PS-A e PS-B ou no índice de apoptose epitelial entre os grupos SDRA e controle. Nossos resultados mostram que as pequenas vias aéreas participam da inflamação pulmonar de pacientes com SDRA, caracterizada pelo aumento na expressão de interleucinas próinflamatórias tanto em células inflamatórias da parede da via aérea quanto no epitélio. Nossos resultados sugerem ainda que a apoptose não é um mecanismo importante de morte de células epiteliais das vias aéreas de pacientes com SDRARecent studies suggest a role for distal airway injury in the pathophysiology of human ALI/ARDS. The epithelium lining the airways modulates airway function secreting a large number of molecules such as surfactant components and inflammatory mediators. So far, there is little information on how these secretory functions of the small airways are altered in ARDS. In the present study we assessed the airway expression of surfactant protein (SP) A and SP B, the expression of inflammatory cytokines IL-6 and IL-8, and an index of airway epithelial apoptosis of patients with ARDS submitted to autopsy and compared the results with those of control subjects. We studied autopsy lungs of 31 ARDS patients (PaO2/FiO2200, 45±14 years, 16 males) and 11 controls (52±16 years, 7 males). Using immunohistochemistry and image analysis, we quantified the expression of IL-6, IL-8 and SP-A and SP-B in the epithelium of small airways (diameter2.0mm). Airway epithelial apoptosis index was obtained with the TUNEL assay and FAS/FASL expression. We also quantified the density of inflammatory cells expressing IL-6 and IL-8 within the small airway walls. ARDS airways showed an increase in the epithelial expression of IL-8 (p=0.006) and an increased density of inflammatory cells expressing IL-6 (p=0.004) and IL-8 (p<0.001) when compared to controls. There were no differences in SP-A and SP-B epithelium expression or in epithelial apoptosis index between ARDS and controls. Our results show that the distal airways are involved in ARDS lung inflammation with higher expression of pro-inflammatory interleukins in both airway epithelial and inflammatory cells. Our results also suggest that apoptosis is not a major mechanism of airway epithelial cell death in ARD

Ineficácia da técnica de alívio de pressão por meio de válvula em insuflar o cuff

Objetivo: Testar a eficácia da técnica de alívio de pressão de cuff por meio de uma válvula em manter níveis de pressão de cuff dentro da normalidade in vitro (Fase 1) e em pacientes internados em unidade de terapia intensiva (Fase 2), bem como testar a reprodutibilidade da técnica utilizando diferentes seringas. Métodos: Na Fase 1, uma cânula orotraqueal foi inserida em um modelo de traqueia. Seringas de 10 e 20mL foram utilizadas para insuflar o cuff da cânula. O cuff foi insuflado lenta e progressivamente até que o êmbolo da seringa se deslocasse em direção contrária da aplicação. Após a pausa do êmbolo, as pressões do balonete foram registradas. Na Fase 2, a mesma manobra de insuflação do cuff foi realizada em 20 pacientes, utilizando-se seringas de 5, 10 e 20mL, e foi comparada com as medidas de um manômetro. O índice de correlação intraclasse e a análise de Bland-Altman foram realizados para verificar a reprodutibilidade e a concordância entre as seringas. Os dados foram expressos como mediana (intervalo interquartil). Resultados: A reprodutibilidade entre as seringas foi nula, com índice de correlação intraclasse variando entre -0,33 e 0,8 (p>0,05). As pressões geradas com as seringas foram superiores à pressão obtida com o manômetro padrão: seringa de 5mL teve 105cmH2O (82,5-120cmH2O); seringa de 10mL teve 69cmH2O (47,5-111,3cmH2O) e seringa de 20mL teve 45cmH2O (35-59,5cmH2O). O teste de Bland-Altman verificou grandes vieses e variabilidade entre as seringas utilizadas, quando estas foram comparadas ao manômetro. Conclusão: O uso de seringas não é eficaz em determinar valores de pressão de cuff seguros em pacientes internados em unidade de terapia intensiva

Mobility therapy and central or peripheral catheter-related adverse events in an ICU in Brazil

OBJECTIVE: To determine whether mobility therapy is associated with central or peripheral catheter-related adverse events in critically ill patients in an ICU in Brazil. METHODS: A retrospective analysis of the daily medical records of patients admitted to the Clinical Emergency ICU of the University of São Paulo School of Medicine Hospital das Clínicas Central Institute between December of 2009 and April of 2011. In addition to the demographic and clinical characteristics of the patients, we collected data related to central venous catheters (CVCs), hemodialysis (HD) catheters and indwelling arterial catheters (IACs): insertion site; number of catheter days; and types of adverse events. We also characterized the mobility therapy provided. RESULTS: Among the 275 patients evaluated, CVCs were used in 49%, HD catheters were used in 26%, and IACs were used in 29%. A total of 1,268 mobility therapy sessions were provided to patients while they had a catheter in place. Catheter-related adverse events occurred in 20 patients (a total of 22 adverse events): 32%, infection; 32%, obstruction; and 32%, accidental dislodgement. We found that mobility therapy was not significantly associated with any catheter-related adverse event, regardless of the type of catheter employed: CVC-OR = 0.8; 95% CI: 0.7-1.0; p = 0.14; HD catheter-OR = 1.04; 95% CI: 0.89-1.21; p = 0.56; or IAC-OR = 1.74; 95% CI: 0.94-3.23; p = 0.07. CONCLUSIONS: In critically ill patients, mobility therapy is not associated with the incidence of adverse events involving CVCs, HD catheters, or IACs

Validity, reliability and applicability of Portuguese versions of sedation-agitation scales among critically ill patients

CONTEXT AND OBJECTIVE: Sedation scales are used to guide sedation protocols in intensive care units (ICUs). However, no sedation scale in Portuguese has ever been evaluated. The aim of this study was to evaluate the validity and reliability of Portuguese translations of four sedation-agitation scales, among critically ill patients: Glasgow Coma Score, Ramsay, Richmond Agitation-Sedation Scale (RASS) and Sedation-Agitation Scale (SAS). DESIGN AND SETTING: Validation study in two mixed ICUs of a university hospital. METHODS: All scales were applied to 29 patients by four different critical care team members (nurse, physiotherapist, senior critical care physician and critical care resident). We tested each scale for interrater reliability and for validity, by correlations between them. Interrater agreement was measured using weighted kappa (k) and correlations used Spearman's test. RESULTS: 136 observations were made on 29 patients. All scales had at least substantial agreement (weighted k 0.68-0.90). RASS (weighted k 0.82-0.87) and SAS (weighted k 0.83-0.90) had the best agreement. All scales had a good and significant correlation with each other. CONCLUSIONS: All scales demonstrated good interrater reliability and were comparable. RASS and SAS showed the best correlations and the best agreement results in all professional categories. All these characteristics make RASS and SAS good scales for use at the bedside, to evaluate sedation-agitation among critically ill patients in terms of validity, reliability and applicability