Impact of Early Passive Exercise With Cycle Ergometer on Ventilator Interaction.

BACKGROUND: Early exercise has been recommended in critically ill patients, but its impact on subject-ventilator interaction is still unclear. Therefore, the aim of this study was to evaluate the occurrence of subject-ventilator asynchrony during passive exercise in mechanically ventilated subjects. METHODS: This study included deeply sedated subjects who were under mechanical ventilation for < 72 h. Subjects were coupled to a cycle ergometer and maintained at rest for 5 min (baseline period). After this period, they started 20 min of passive exercise, followed by 10 min of rest (recovery period). The occurrence of asynchrony was monitored by the analysis of flow and airway pressure waveforms, registered throughout the protocol during the baseline, exercise, and recovery periods. Hemodynamic and respiratory parameters were registered at the end of each period. Finally, arterial blood gas analysis was performed twice, at the end of the baseline period and at the end of the recovery period. RESULTS: 8 subjects were enrolled (63.3 ± 16.7 y old, 50% male). The asynchrony index increased during exercise (median 32.1% [interquartile range (IQR) 18.6-47.6%]), compared to baseline (median 6.6% [IQR 3.9-10.4%]), returning to initial levels during the recovery period (median 2.7% [IQR 0-12.2%]). The most frequent types of asynchrony were ineffective triggering (index of 11.8% [IQR 1.2-22.5%] during exercise, compared to 2.0% [IQR 1.4-4.4%] at baseline), and insufficient flow (index of 11.7% [IQR 4.7-19.3%] during exercise, compared to 2.0% [IQR 1.1 to 3.3%] at baseline). There were no significant changes in the hemodynamic and respiratory variables. CONCLUSIONS: Early cycle ergometer passive exercise in deeply sedated subjects can worsen subject-ventilator interaction, due to ineffective triggering and insufficient flow. Adjustments in the ventilatory parameters may be necessary to avoid asynchrony during exercise.

Association between exercise training in haemodialysis patients and burden of their family caregivers: A cross-sectional study.

AIM: Considering that exercise programmes are related with a range of benefits for end-stage renal disease patients, we evaluated the association between haemodialysis (HD) patients' involvement in intradialytic exercise training with the burden of their family caregivers. METHODS: In this cross-sectional study, 60 caregivers of HD patients were recruited, 30 of them who cared for patients that regularly participated in an exercise programme during dialysis sessions and 30 caregivers who looked after patients undergoing usual HD treatment without intradialytic exercise. The caregivers were submitted to the Caregiver Burden Scale (CBS) and their quality of life (short-form-36 (SF-36)), anxiety and depression levels were assessed. Data were expressed as mean ± SD or median (interquartile range). RESULTS: Multiple linear regression showed that the global CBS score was significantly associated with the exercise training after adjusting for age, educational level and anxiety level of caregivers, and dependency level of patients measured by the Lawton scale (coefficient of determination = 0.53; adjusted coefficient of determination = 0.48). Additionally, the caregivers of HD patients submitted to intradialytic exercise (42.0 ± 12.9 years, 33.3% male) compared to caregivers of patients undergoing usual treatment (50.7 ± 17.5 years, 26.7% male) exhibited less caregiver burden (global CBS score = 1.2 (0.2) vs 1.9 (0.7), P < 0.001), better quality of life (physical component score = 53.7 (9.6) vs 49.7 (16.2) and mental component score = 50.6 (17.5) vs 28.2 (32.5), P < 0.05) and lower anxiety (7.2 ± 4.2 vs 10.8 ± 4.1, P = 0.001) and depression levels (3.0 (3.3) vs 6.0 (5.3), P = 0.034), respectively. CONCLUSIONS: Intradialytic exercise training in HD patients was associated with lower burden of their family caregivers.

Emphysema induced by elastase alters the mRNA relative levels from DNA repair genes in acute lung injury in response to sepsis induced by lipopolysaccharide administration in Wistar rats.

Purpose/Aim of the study: Patients suffering from chronic obstructive pulmonary disease (COPD) in association with acute respiratory distress syndrome (ARDS) present oxidative stress in lung cells, with production of free radicals and DNA lesions in pulmonary and adjacent cells. Once the DNA molecule is damaged, a set of enzymatic mechanisms are trigged to preserve genetic code integrity and cellular homeostasis. These enzymatic mechanisms include the base and the nucleotide excision repair pathways, as well as telomere regulation. Thus, the aim of this work was to evaluate the mRNA levels from APEX1, ERCC2, TP53, and TRF2 genes in lung tissue from Wistar rats affected by acute lung injury in response to sepsis and emphysema. MATERIALS AND METHODS: Adult male Wistar rats were randomized into 4 groups (n = 6, for each group): control, emphysema, sepsis, and emphysema with sepsis. Pulmonary emphysema was induced by intratracheal instillation of elastase (12 IU/animal) and sepsis induced by intraperitoneal Escherichia coli lipopolysaccharide (LPS) injection (10 mg/kg). Lungs were removed, and samples were withdrawn for histological analysis and total RNA extraction, cDNA synthesis, and mRNA level evaluation by real time quantitative polymerase chain reaction. RESULTS: Data show acute lung injury by LPS and emphysema by elastase and that APEX1, ERCC2, TP53, and TRF2 mRNA levels are increased significantly (p < 0.01) in emphysema with sepsis group. CONCLUSION: Our results suggest that alteration in mRNA levels from DNA repair and genomic stability could be part of cell response to acute lung injury in response to emphysema and sepsis.

Intra-dialytic training accelerates oxygen uptake kinetics in hemodialysis patients.

BACKGROUND: End-stage renal disease is associated with several hemodynamic and peripheral muscle abnormalities that could slow the rate of change in oxygen uptake ([Formula: see text]O2) at the onset and at the end of exercise. This study was performed to determine whether an intra-dialytic aerobic training program would speed [Formula: see text]O2 kinetics at the transition to and from moderate and high-intensity exercise. DESIGN: This study was a randomized controlled trial. METHODS: Twenty-four patients with end-stage renal disease (14 females; 47.0 ± 11.9 years) were randomly assigned to either 12-week cycle ergometer-based training at moderate exertion or a similar control period. At initial and final evaluations, patients underwent 6 min moderate and high-intensity tests to exercise intolerance (Tlim). RESULTS: Training improved Tlim by ∼90% (median (inter-quartile range) = 232 (59) s to 445 (451) s, p < 0.05); in contrast, Tlim decreased by ∼30% in controls (291 (134) s to 202 (131) s). [Formula: see text]O2 kinetics at the onset of moderate-intensity exercise were significantly accelerated with training leading to lower oxygen (O2) deficit (mean ± standard deviation (SD) = 3.2 ± 1.3 l vs 2.3 ± 1.2 l). Similar positive effects were found at the high-intensity test either at the onset of, or recovery from, exercise (p < 0.05). "Excess" [Formula: see text]O2 at the high-intensity test was also lessened with training. Changes in Tlim correlated with faster [Formula: see text]O2 kinetics and lower "excess" [Formula: see text]O2 (Spearman's ρ = -0.56 and -0.75, respectively; p < 0.01). CONCLUSIONS: A symptom-targeted intra-dialytic training program improved sub-maximal aerobic metabolism and endurance exercise capacity. [Formula: see text]O2 kinetics are valuable in providing relatively effort-independent information on the efficacy of exercise interventions in this patient population.

Constant work-rate test to assess the effects of intradialytic aerobic training in mildly impaired patients with end-stage renal disease: a randomized controlled trial.

OBJECTIVE: To investigate if high-intensity constant work rate (CWR) would constitute a more appropriate testing strategy compared with incremental work rate (IWR) to assess the effectiveness of intradialytic aerobic training in patients with end-stage renal disease (ESRD). DESIGN: Randomized controlled trial. SETTING: Nephrology unit at the university hospital. PARTICIPANTS: Patients (N=28; 47.0±11.9y) under hemodialysis (4.4±4.3y) were randomly assigned to exercise and control groups. INTERVENTION: Patients included in the exercise group underwent a moderate-intensity intradialytic aerobic training program 3 times per week for 12 weeks. MAIN OUTCOME MEASURES: Cardiopulmonary and perceptual responses were obtained during an IWR and a high-intensity CWR test to the limit of tolerance on a cycle ergometer. RESULTS: Training-induced increases in peak oxygen uptake (Vo(2)peak) and time to exercise intolerance (Tlim). Mean improvement in Tlim (97.4%±75.6%) was significantly higher than increases in Vo(2)peak (12%±11.3%) (P<.01); in fact, while Tlim improved 50% to 200% in 9 of 12 patients, Vo(2)peak increases were typically in the 15% to 20% range. CWR test revealed lower metabolic, ventilatory, cardiovascular, and subjective stresses at isotime; in contrast, submaximal responses during the incremental work rate (at the gas exchange threshold) remained unaltered after training. CONCLUSIONS: A laboratory-based measure of endurance exercise capacity (high-intensity CWR test to Tlim) was substantially more sensitive than oxygen uptake at the peak IWR test to unravel the physiologic benefits of an intradialytic aerobic training program in mildly impaired patients with ESRD.

Fatores de risco na síndrome do desconforto respiratório agudo / Risk factors for acute respiratory distress syndrome

A síndrome do desconforto respiratório agudo (SDRA) é uma condição crítica que consiste de insuficiência respiratória hipoxêmica aguda grave, com infiltrados pulmonares bilaterais que não são atribuídos a hipertensão atrial esquerda. Trata-se de uma desordem heterogênea que pode ser desencadeada por variadas etiologias. Um melhor conhecimento de seus fatores de risco pode ajudar no seu diagnóstico precoce. Os fatores de risco para SDRA têm permanecido os mesmos por vários anos e incluem pneumonia, sepse, aspiração de conteúdo gástrico, trauma grave e múltiplas transfusões, dentre outros. Essas condições clínicas podem ser divididas entre aquelas associadas à lesão direta dos pulmões (fatores pulmonares) e àquelas que causam lesão indireta, no contexto de um processo sistêmico (fatores extrapulmonares). Enquanto alguns autores argumentam que esses fatores resultam em apresentações diferentes, as implicações clínicas dessa classificação não foram bem estabelecidas. Outras condições podem aumentar a suscetibilidade para SDRA, como abuso de álcool, obesidade e ventilação mecânica com altos volumes correntes e altas pressões de vias aéreas; por outro lado, diabetes parece reduzir o risco de desenvolvimento de SDRA. Nos últimos anos, especial interesse tem surgido em estudos sobre predisposição genética à SDRA, e, no futuro, eles poderão ajudar na compreensão do motivo pelo qual apenas alguns pacientes com estímulo patológico desenvolvem a síndrome.

Acute respiratory distress syndrome (ARDS) results in critical illness consisting of acute severe hypoxemic respiratory failure with bilateral pulmonary infiltrates that are not attributable to left atrial hypertension. It is a heterogeneous disorder that can be triggered by myriad etiologies. Greater knowledge of the risk factors involved could increase the rate of early ARDS diagnosis. The risk factors for ARDS, which have remained the same for several years, include pneumonia, sepsis, aspiration of gastric contents, severe trauma, and multiple transfusions. These can be divided into those associated with direct injury to the lung (pulmonary factors) and those that cause indirect lung injury in the setting of a systemic process (extrapulmonary factors). Although some authors argue that the various risk factors provoke different presentations, the clinical implications have not been clarified. Other conditions that can increase susceptibility to ARDS include alcohol abuse, obesity, and mechanical ventilation with high tidal volume and high airway pressure. However, diabetes seems to reduce the risk of developing ARDS. In recent years, there has been increased interest in the study of genetic predisposition to ARDS, which might eventually prove helpful in explaining why only some patients with pathologic stimuli develop the syndrome.