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Left ventricular diastolic dysfunction is a common finding in critically ill patients. It is characterized by a progressive deterioration of the relaxation and the compliance of the left ventricle. Two-dimensional and Doppler echocardiography is a cornerstone in its diagnosis. Acute pulmonary edema associated with hypertensive crisis is the most frequent presentation of diastolic dysfunction critically ill patients. Myocardial ischemia, sepsis and weaning failure from mechanical ventilation also may be associated with diastolic dysfunction. The treatment is based on the reduction of pulmonary congestion and left ventricular filling pressures. Some studies have found a prognostic role of diastolic dysfunction in some diseases such as sepsis. The present review aims to analyze thoroughly the echocardiographic diagnosis and the most frequent scenarios in critically ill patients in whom diastolic dysfunction plays a key role.
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Estado Terminal , Ecocardiografia Doppler , Disfunção Ventricular Esquerda/diagnóstico por imagem , Cardiomiopatias , Ecocardiografia , Insuficiência Cardíaca , HumanosRESUMO
OBJECTIVES: 1) To assess the prevalence of pain during nursing care procedures, and 2) to evaluate the usefulness of certain vital signs and the bispectral index (BIS) in detecting pain. METHODS: A prospective, observational analytical study was made of procedures (endotracheal aspiration and mobilization with turning) in critically ill sedated patients on mechanical ventilation. The Behavioral Pain Scale was used to assess pain, with scores of ≥3 indicating pain. Various physiological signs and BIS values were recorded, with changes of >10% being considered clinically relevant. RESULTS: A total of 146 procedures in 70 patients were analyzed. Pain prevalence during the procedures was 94%. Vital signs and BIS values increased significantly during the procedures compared to resting conditions, but only the changes in BIS were considered clinically relevant. In the subgroup of patients receiving preemptive analgesia prior to the procedure, pain decreased significantly compared to the group of patients who received no such analgesia (-2 [IQR: {-5}-0] vs. 3 [IQR: 1-4]; P<.001, respectively). CONCLUSIONS: The procedures evaluated in this study are painful. Changes in vital signs are not good indicators of pain. Changes in BIS may provide useful information about pain, but more research is needed. The administration of preemptive analgesia decreases pain during the procedures.
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Medição da Dor , Dor , Respiração Artificial , Aspiração Respiratória , Sinais Vitais , Analgesia , Cuidados Críticos , Estado Terminal , Humanos , Estudos ProspectivosRESUMO
OBJECTIVES: To compare tolerance, duration of mechanical ventilation (MV) and clinical outcomes during weaning from MV in patients subjected to either pressure support ventilation (PSV) or proportional assist ventilation (PAV). DESIGN: A prospective, observational study was carried out. SETTING: Intensive Care Unit. PATIENTS: A total of 40 consecutive subjects were allocated to either the PSV or the PAV group until each group contained 20 patients. Patients were included in the study when they met the criteria to begin weaning and the attending physician decided to initiate the weaning process. The physician selected the modality and set the ventilatory parameters. INTERVENTIONS: None. VARIABLES OF INTEREST: Demographic data, respiratory mechanics, ventilatory parameters, duration of MV, and clinical outcomes (reintubation, tracheostomy, mortality). RESULTS: Baseline characteristics were similar in both groups. No significant differences were observed between the PSV and PAV groups in terms of the total duration of MV (10 [5-18] vs. 9 [7-19] days; P=.85), reintubation (5 [31%] vs. 3 [19%]; P=.69), or mortality (4 [20%] vs. 5 [25%] deaths; P=1). Eight patients (40%) in the PSV group and 6 patients (30%) in the PAV group (P=.74) required a return to volume assist-control ventilation due to clinical deterioration. CONCLUSIONS: Tolerance, duration of MV and clinical outcomes during weaning from mechanical ventilation were similar in PSV and PAV.
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Respiração Artificial , Desmame do Respirador/métodos , Idoso , Feminino , Humanos , Suporte Ventilatório Interativo , Masculino , Pessoa de Meia-Idade , Estudos ProspectivosRESUMO
Intensive care medical training, whether as a primary specialty or as secondary add-on training, should include key competences to ensure a uniform standard of care, and the number of intensive care physicians needs to increase to keep pace with the growing and anticipated need. The organisation of intensive care in multiple specialty or central units is heterogeneous and evolving, but appropriate early treatment and access to a trained intensivist should be assured at all times, and intensivists should play a pivotal role in ensuring communication and high-quality care across hospital departments. Structures now exist to support clinical research in intensive care medicine, which should become part of routine patient management. However, more translational research is urgently needed to identify areas that show clinical promise and to apply research principles to the real-life clinical setting. Likewise, electronic networks can be used to share expertise and support research. Individuals, physicians and policy makers need to allow for individual choices and priorities in the management of critically ill patients while remaining within the limits of economic reality. Professional scientific societies play a pivotal role in supporting the establishment of a defined minimum level of intensive health care and in ensuring standardised levels of training and patient care by promoting interaction between physicians and policy makers. The perception of intensive care medicine among the general public could be improved by concerted efforts to increase awareness of the services provided and of the successes achieved.
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Cuidados Críticos/tendências , Medicina/tendências , PrevisõesRESUMO
Acute respiratory distress syndrome (ARDS) is characterized by local inflammation and an intense systemic inflammatory reaction. Glucocorticoid administration has been suggested due to their anti-inflammatory properties. However, results from the initial studies of glucocorticoids in ARDS, which evaluated high-dose and short-term treatments, were negative. More recent studies have evaluated the effect of lower doses of glucocorticoids administered over longer periods, but the results thus far have been inconclusive.
Le syndrome de détresse respiratoire aiguë (SDRA) est caractérisé par une inflammation locale et une réaction inflammatoire systémique intense. L'administration de glucocorticoïdes a été proposée en raison de leurs propriétés anti-inflammatoires. Cependant, les résultats des premières études concernant la prescription des glucocorticoïdes dans le SDRA, qui ont évalué de hautes doses avec des traitements de court terme, ont été négatifs. Des études plus récentes ont évalué des doses plus basses administrées sur des périodes plus longues, mais les résultats ont aussi été peu concluants.
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BACKGROUND: The objective was to study the antipyretic and hemodynamic effects of three different drugs used to treat fever in critically ill patients. DESIGN AND SETTING: Prospective, observational study in a 16-bed, general ICU of a university hospital. PATIENT POPULATION: We studied 150 patients who had a febrile episode (temperature>38°C): 50 received paracetamol, 50 metamizol and 50 dexketoprofen. INTERVENTIONS: None. Body temperature, systolic, diastolic and mean arterial pressure, heart rate, central venous pressure and oxygen saturation were determined at baseline and at 30, 60 and 120minutes after infusion of the drug. Additionally, we recorded temperature 180minutes after starting drug infusion. Diuresis and the need for or change of dose of vasodilator or vasoconstrictor drugs were also recorded. RESULTS: Patient characteristics, baseline temperature and hemodynamics were similar in all groups. We observed a significant decrease of at least 1°C in temperature after 180minutes in 38 patients treated with dexketoprofen (76%), in 36 with metamizol (72%), and in 20 with paracetamol (40%) (p<0.001). After 120minutes, the mean decrease in mean arterial pressure was 8.5±13.6mmHg with paracetamol, 14.9±11.8mmHg with metamizol, and 16.8±13.7mmHg with dexketoprofen (p=0.005). CONCLUSIONS: Dexketoprofen was the most effective antipyretic agent at the doses tested. Although all three drugs reduced mean arterial pressure, the reduction with paracetamol was less pronounced.
Assuntos
Acetaminofen/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Antipiréticos/farmacologia , Dipirona/farmacologia , Febre/tratamento farmacológico , Hemodinâmica/efeitos dos fármacos , Cetoprofeno/análogos & derivados , Trometamina/farmacologia , Acetaminofen/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Anti-Inflamatórios não Esteroides/uso terapêutico , Antipiréticos/uso terapêutico , Estado Terminal , Dipirona/uso terapêutico , Feminino , Humanos , Cetoprofeno/farmacologia , Cetoprofeno/uso terapêutico , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Trometamina/uso terapêutico , Adulto JovemRESUMO
PURPOSE: To evaluate changes in the disconnection of mechanical ventilation in Spain from 1998 to 2016. DESIGN: Post-hoc analysis of four cohort studies. AMBIT: 138 Spanish ICUs. PATIENTS: 2141 patients scheduled extubated. INTERVENTIONS: None. VARIABLES OF INTEREST: Demographics, reason for mechanical ventilation, complications, methods for disconnection, failure on the first attempt at disconnection, duration of weaning, reintubation, post-reintubation tracheotomy, ICU stay and mortality. RESULTS: There was a significant increase (p < 0.001) in the use of gradual reduction of support pressure. The adjusted probability of using the gradual reduction in pressure support versus a spontaneous breathing trial has increased over time, both for the first attempt at disconnection (taking the 1998 study as a reference: odds ratio 0.99 in 2004, 0.57 in 2010 and 2.43 in 2016) and for difficult/prolonged disconnection (taking the 1998 study as a reference: odds ratio 2.29 in 2004, 1.23 in 2010 and 2.54 in 2016). The proportion of patients extubated after the first attempt at disconnection has increased over time. There is a decrease in the ventilation time dedicated to weaning (from 45% in 1998 to 36% in 2016). However, the duration in difficult/prolonged weaning has not decreased (median 3 days in all studies, p = 0.435). CONCLUSIONS: There have been significant changes in the mode of disconnection of mechanical ventilation, with a progressive increase in the use of gradual reduction of pressure support. No relevant changes in outcomes have been observed.
Assuntos
Respiração Artificial , Desmame do Respirador , Extubação , Estudos de Coortes , Humanos , Respiração com Pressão Positiva/métodos , Respiração Artificial/métodos , Espanha , Desmame do Respirador/métodosRESUMO
Alveolar recruitment in acute respiratory distress syndrome (ARDS) is defined as the penetration of gas into previously unventilated areas or poorly ventilated areas. Alveolar recruitment during recruitment maneuvering (RM) depends on the duration of the maneuver, the recruitable lung tissue, and the balance between the recruitment of collapsed areas and over-insufflation of the ventilated areas. Alveolar recruitment is estimated using computed tomography of the lung and, at the patient bedside, through assessment of the recruited volume using pressure-volume curves and assessing lung morphology with pulmonary ultrasound and/or impedance tomography. The scientific evidence on RM in patients with ARDS remains subject to controversy. Randomized studies on ARDS have shown no benefit or have even reflected an increase in mortality. The routine use of RM is therefore not recommended.
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Síndrome do Desconforto Respiratório , Impedância Elétrica , Humanos , Pulmão/diagnóstico por imagem , Respiração com Pressão Positiva , Síndrome do Desconforto Respiratório/terapia , Tomografia Computadorizada por Raios XRESUMO
PURPOSE: To evaluate changes in the disconnection of mechanical ventilation in Spain from 1998 to 2016. DESIGN: Post-hoc analysis of four cohort studies. AMBIT: 138 Spanish ICUs. PATIENTS: 2141 patients scheduled extubated. INTERVENTIONS: None. VARIABLES OF INTEREST: Demographics, reason for mechanical ventilation, complications, methods for disconnection, failure on the first attempt at disconnection, duration of weaning, reintubation, post-reintubation tracheotomy, ICU stay and mortality. RESULTS: There was a significant increase (p<0.001) in the use of gradual reduction of support pressure. The adjusted probability of using the gradual reduction in pressure support versus a spontaneous breathing trial has increased over time, both for the first attempt at disconnection (taking the 1998 study as a reference: odds ratio 0.99 in 2004, 0.57 in 2010 and 2.43 in 2016) and for difficult/prolonged disconnection (taking the 1998 study as a reference: odds ratio 2.29 in 2004, 1.23 in 2010 and 2.54 in 2016). The proportion of patients extubated after the first attempt at disconnection has increased over time. There is a decrease in the ventilation time dedicated to weaning (from 45% in 1998 to 36% in 2016). However, the duration in difficult/prolonged weaning has not decreased (median 3 days in all studies, p=0.435). CONCLUSIONS: There have been significant changes in the mode of disconnection of mechanical ventilation, with a progressive increase in the use of gradual reduction of pressure support. No relevant changes in outcomes have been observed.
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PURPOSE: To evaluate changes in the epidemiology of mechanical ventilation in Spain from 1998 to 2016. DESIGN: A post hoc analysis of four cohort studies was carried out. SETTING: A total of 138 Spanish ICUs. PATIENTS: A sample of 4293 patients requiring invasive mechanical ventilation for more than 12h or noninvasive ventilation for more than 1h. INTERVENTIONS: None. VARIABLES OF INTEREST: Demographic variables, reason for mechanical ventilation, variables related to ventilatory support (ventilation mode, tidal volume, PEEP, airway pressures), complications during mechanical ventilation, duration of mechanical ventilation, ICU stay and ICU mortality. RESULTS: There was an increase in severity (SAPSII: 43 points in 1998 vs. 47 points in 2016), changes in the reason for mechanical ventilation (decrease in chronic obstructive pulmonary disease and acute respiratory failure secondary to trauma, and increase in neurological disease and post-cardiac arrest). There was an increase in noninvasive mechanical ventilation as the first mode of ventilatory support (p<0.001). Volume control ventilation was the most commonly used mode, with increased support pressure and pressure-regulated volume-controlled ventilation. A decrease in tidal volume was observed (9ml/kg actual b.w. in 1998 and 6.6ml/kg in 2016; p<0.001) as well as an increase in PEEP (3cmH2O in 1998 and 6cmH2O in 2016; p<0.001). In-ICU mortality decreased (34% in 1998 and 27% in 2016; p<0.001), without geographical variability (median OR 1.43; p=0.258). CONCLUSIONS: A significant decrease in mortality was observed in patients ventilated in Spanish ICUs. These changes in mortality could be related to modifications in ventilation strategy to minimize ventilator-induced lung injury.
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BACKGROUND: Extracorporeal CO2 removal (ECCO2R) could be a valuable additional modality for invasive mechanical ventilation (IMV) in COPD patients suffering from severe acute exacerbation (AE). We aimed to evaluate in such patients the effects of a low-to-middle extracorporeal blood flow device on both gas exchanges and dynamic hyperinflation, as well as on work of breathing (WOB) during the IMV weaning process. STUDY DESIGN AND METHODS: Open prospective interventional study in 12 deeply sedated IMV AE-COPD patients studied before and after ECCO2R initiation. Gas exchange and dynamic hyperinflation were compared after stabilization without and with ECCO2R (Hemolung, Alung, Pittsburgh, USA) combined with a specific adjustment algorithm of the respiratory rate (RR) designed to improve arterial pH. When possible, WOB with and without ECCO2R was measured at the end of the weaning process. Due to study size, results are expressed as median (IQR) and a non-parametric approach was adopted. RESULTS: An improvement in PaCO2, from 68 (63; 76) to 49 (46; 55) mmHg, p = 0.0005, and in pH, from 7.25 (7.23; 7.29) to 7.35 (7.32; 7.40), p = 0.0005, was observed after ECCO2R initiation and adjustment of respiratory rate, while intrinsic PEEP and Functional Residual Capacity remained unchanged, from 9.0 (7.0; 10.0) to 8.0 (5.0; 9.0) cmH2O and from 3604 (2631; 4850) to 3338 (2633; 4848) mL, p = 0.1191 and p = 0.3013, respectively. WOB measurements were possible in 5 patients, indicating near-significant higher values after stopping ECCO2R: 11.7 (7.5; 15.0) versus 22.6 (13.9; 34.7) Joules/min., p = 0.0625 and 1.1 (0.8; 1.4) versus 1.5 (0.9; 2.8) Joules/L, p = 0.0625. Three patients died in-ICU. Other patients were successfully hospital-discharged. CONCLUSIONS: Using a formalized protocol of RR adjustment, ECCO2R permitted to effectively improve pH and diminish PaCO2 at the early phase of IMV in 12 AE-COPD patients, but not to diminish dynamic hyperinflation in the whole group. A trend toward a decrease in WOB was also observed during the weaning process. Trial registration ClinicalTrials.gov: Identifier: NCT02586948.
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BACKGROUND: This systematic review and meta-analysis summarizes the safety and efficacy of high flow nasal cannula (HFNC) in patients with acute hypoxemic respiratory failure. METHODS: We performed a comprehensive search of MEDLINE, EMBASE, and Web of Science. We identified randomized controlled trials that compared HFNC to conventional oxygen therapy. We pooled data and report summary estimates of effect using relative risk for dichotomous outcomes and mean difference or standardized mean difference for continuous outcomes, with 95% confidence intervals. We assessed risk of bias of included studies using the Cochrane tool and certainty in pooled effect estimates using GRADE methods. RESULTS: We included 9 RCTs (n = 2093 patients). We found no difference in mortality in patients treated with HFNC (relative risk [RR] 0.94, 95% confidence interval [CI] 0.67-1.31, moderate certainty) compared to conventional oxygen therapy. We found a decreased risk of requiring intubation (RR 0.85, 95% CI 0.74-0.99) or escalation of oxygen therapy (defined as crossover to HFNC in the control group, or initiation of non-invasive ventilation or invasive mechanical ventilation in either group) favouring HFNC-treated patients (RR 0.71, 95% CI 0.51-0.98), although certainty in both outcomes was low due to imprecision and issues related to risk of bias. HFNC had no effect on intensive care unit length of stay (mean difference [MD] 1.38 days more, 95% CI 0.90 days fewer to 3.66 days more, low certainty), hospital length of stay (MD 0.85 days fewer, 95% CI 2.07 days fewer to 0.37 days more, moderate certainty), patient reported comfort (SMD 0.12 lower, 95% CI 0.61 lower to 0.37 higher, very low certainty) or patient reported dyspnea (standardized mean difference [SMD] 0.16 lower, 95% CI 1.10 lower to 1.42 higher, low certainty). Complications of treatment were variably reported amongst included studies, but little harm was associated with HFNC use. CONCLUSION: In patients with acute hypoxemic respiratory failure, HFNC may decrease the need for tracheal intubation without impacting mortality.
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Oxigenoterapia/métodos , Insuficiência Respiratória/terapia , Cânula/normas , Humanos , Hipóxia/terapia , Oxigênio/administração & dosagem , Oxigenoterapia/instrumentação , Oxigenoterapia/normas , Insuficiência Respiratória/classificação , Insuficiência Respiratória/fisiopatologia , Resultado do TratamentoRESUMO
INTRODUCTION: In Venezuela, no large studies have been conducted to determine the level of control of hypertension (HT). OBJECTIVE: The primary objective was to know the prevalence of controlled HT among hypertensive patients treated pharmacologically. MATERIALS AND METHODS: A cross-section study was conducted on patients 18years and older. RESULTS: A total of 4,320 patients were included. The prevalence of controlled hypertension was 52.6% (95%CI: 51.1-54.1%). The lack of control of HT was associated with diabetes (P<.001), hypertensive heart disease (P<.001), chronic kidney disease (P<.001), and peripheral arterial disease (P=.02). Non-compliance of treatment was also associated with uncontrolled HT (5.1% [117/2,274] in the controlled versus 43.2% [885/2,046] in the uncontrolled; (P<.001). CONCLUSION: The prevalence detected of controlled hypertension was 52.6%.
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Anti-Hipertensivos/administração & dosagem , Hipertensão/tratamento farmacológico , Adesão à Medicação/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Hipertensão/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Sistema de Registros , Fatores de Risco , Resultado do Tratamento , VenezuelaRESUMO
OBJECTIVE: The aim of the present article is to summarize the results we obtained treating children with urolithiasis over the last 30 years and to perform an analysis on the basis of the these results and relevant details according to national and international experience. METHODS: Retrospective and descriptive statistical analysis of the 30 year experience in our clinics. The study was performed with a sample size of 178 children treated with urolithiasis that underwent 221 procedures. These procedures include ESWL, ureterorenoscopy (URS) and percutaneous nephrolithotomy (PCNL). CONCLUSIONS: We conclude in this study that ESWL in children was the most appropriate procedure for renal and proximal and middle-third ureteral lithiasis. Kidney stones measuring 2 to 3 cm can be treated without additional procedures or combined approaches. In contrast cystine stones caused the major problems for fragmentation. Moreover, the use of double J catheters increased the need for ESWL when catheter calcification occurred and endoscopic removal was impossible. The benefits of this method must be individually assessed both for the benefit of the temporary placement as well as for the expectation of permanence. We conclude that URS is the best choice for distal-third ureteral lithiasis and some cases of proximal and middle- third ureteral lithiasis. This enables for simultaneous treatments, ureteral dilatation and unexpected diagnoses. In particular, rigid ureteroscopy offers adjuvant options to ESWL with great therapeutic potential and easy handling. In consequence, to our good results and cost-benefit balance using ESWL and rigid URS (even combined), the use of flexible URS for renal lithiasis has been reduced. In general community units like ours, the combined PCNL has been indicated for particular complex cases, and open or laparoscopic surgery was not necessary in any case.
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Cálculos Renais/terapia , Litotripsia , Cálculos Ureterais/terapia , Criança , Hospitais , Humanos , Estudos RetrospectivosRESUMO
OBJECTIVE: This study examined the incidence and mortality of multiple organ dysfunction syndrome (MODS) in intensive care units, evaluated the limitation of life support in these patients, and determined whether daily measurement of the Sequential Organ Failure Assessment (SOFA) is useful for decision making. DESIGN AND SETTING: Prospective, observational study in 79 intensive care units. PATIENTS AND PARTICIPANTS: Of the 7,615 patients admitted during a 2-month period we found 1,340 patients to have MODS. MEASUREMENTS AND RESULTS: We recorded mortality and length of stay in the intensive care unit and the hospital and the maximum and minimum total SOFA scores during MODS. Limitation of life support in MODS patients was also evaluated. Stepwise logistic regression was used to determine the factors predicting mortality. The in-hospital mortality rate in patients with MODS was 44.6%, and some type of limitation of life support was applied in 70.6% of the patients who died. The predictive model maximizing specificity included the following variables: maximum SOFA score, minimum SOFA score, trend of the SOFA for 5 consecutive days, and age over 60 years. The model diagnostic yield was: specificity 100%, sensitivity 7.2%, positive predictive value 100%, and negative predictive value 57.3%; the area under the receiver operating characteristic curve was 0.807. CONCLUSIONS: This model showed that in our population with MODS those older than 60 years and with SOFA score higher than 9 for at least 5 days were unlikely to survive.
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Unidades de Terapia Intensiva , Cuidados para Prolongar a Vida , Insuficiência de Múltiplos Órgãos/mortalidade , Tomada de Decisões , Feminino , Humanos , Incidência , Tempo de Internação , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Insuficiência de Múltiplos Órgãos/epidemiologia , Insuficiência de Múltiplos Órgãos/terapia , Valor Preditivo dos Testes , Curva ROC , Índice de Gravidade de Doença , Espanha/epidemiologiaRESUMO
Differences between assist-control pressure and volume ventilation are minimal provided that peak inspiratory flow delivered at early inspiration matches patient demand Ventilation at constant flow and controlled tidal volume allow instantaneous analysis of the patient-ventilator interactions and the mechanical properties of the respiratory system. The cycle-per-cycle variability of peak inspiratory flow, which is permitted in pressure-limited modes, may allow better patient comfort. We do not know if one mode (pressure controlled or volume controlled) is superior to the other in terms of outcomes.
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Ventilação Pulmonar/fisiologia , Respiração Artificial/instrumentação , Gasometria , Desenho de Equipamento , Humanos , Mecânica Respiratória/fisiologia , Volume de Ventilação PulmonarRESUMO
The distinction between native and introduced biotas presents unique challenges that culminate in organisms with high long-distance dispersal capacities in a rapidly changing world. Bryophytes, in particular, exhibit large distribution ranges, and some species can truly be qualified as cosmopolitan. Cosmopolitan species, however, typically occur in disturbed environments, raising the question of their nativeness throughout their range. Here, we employ genetic data to address the question of the origin of the cosmopolitan, weedy moss Bryum argenteum on the island of Tenerife. The genetic diversity of B. argenteum on Tenerife was comparable to that found in continental areas due to recurrent colonisation events, erasing any signature of a bottleneck that would be expected in the case of a recent colonisation event. The molecular dating analyses indicated that the first colonisation of the island took place more than 100,000 years ago, i.e. well before the first human settlements. Furthermore, the significant signal for isolation-by-distance found in B. argenteum within Tenerife points to the substantial role of genetic drift in establishing the observed patterns of genetic variation. Together, the results support the hypothesis that B. argenteum is native on Tenerife; although the existence of haplotypes shared between Tenerife and continental areas suggests that more recent, potentially man-mediated introduction also took place. While defining nativeness in organisms that are not deliberately introduced, and wherein the fossil record is extremely scarce, is an exceedingly challenging task, our results suggest that population genetic analyses can represent a useful tool to help distinguish native from alien populations.