First-in-human experience of preload regulation with percutaneous transluminal caval flow regulation in heart failure with reduced ejection fraction patients.

AIMS: This study aims to investigate the acute haemodynamic effects of percutaneous transluminal flow regulation (PTCR®) with an inferior vena cava regulator balloon in heart failure patients. Preload reduction in heart failure has been achieved with high potency diuretics. However, no study has been conducted in humans to assess the effect of inferior vena cava intermittent occlusion for preload reduction. METHODS AND RESULTS: Six patients were included in the study: four men (55 ± 6 years old) and two women (63 ± 4 years old). Baseline evaluations included Doppler echocardiogram, coronary angiogram, and right heart catheterization. Caval balloon was kept inflated for 30 min, and right catheterization and control echocardiogram were performed while the balloon was still inflated. The balloon was then deflated and removed. Right haemodynamic variables were evaluated before balloon insertion and with the inflated balloon. The mean right atrial pressure decreased by 42.59% (P = 0.005); systolic right ventricular pressure decreased by 30.19% (P < 0.003); mean pulmonary arterial pressure decreased by 25.33% (P < 0.043); mean pulmonary capillary wedge pressure decreased by 31.37% (P > 0.016); and cardiac output increased by 9.92% (P < 0.175). CONCLUSIONS: The haemodynamic and echocardiographic changes obtained in our study using PTCR® suggest that this innovative approach can play a beneficial role in the heart failure treatment.

Severe hypercapnia and outcome of mechanically ventilated patients with moderate or severe acute respiratory distress syndrome.

PURPOSE: To analyze the relationship between hypercapnia developing within the first 48 h after the start of mechanical ventilation and outcome in patients with acute respiratory distress syndrome (ARDS). PATIENTS AND METHODS: We performed a secondary analysis of three prospective non-interventional cohort studies focusing on ARDS patients from 927 intensive care units (ICUs) in 40 countries. These patients received mechanical ventilation for more than 12 h during 1-month periods in 1998, 2004, and 2010. We used multivariable logistic regression and a propensity score analysis to examine the association between hypercapnia and ICU mortality. MAIN OUTCOMES: We included 1899 patients with ARDS in this study. The relationship between maximum PaCO2 in the first 48 h and mortality suggests higher mortality at or above PaCO2 of ≥50 mmHg. Patients with severe hypercapnia (PaCO2 ≥50 mmHg) had higher complication rates, more organ failures, and worse outcomes. After adjusting for age, SAPS II score, respiratory rate, positive end-expiratory pressure, PaO2/FiO2 ratio, driving pressure, pressure/volume limitation strategy (PLS), corrected minute ventilation, and presence of acidosis, severe hypercapnia was associated with increased risk of ICU mortality [odds ratio (OR) 1.93, 95% confidence interval (CI) 1.32 to 2.81; p = 0.001]. In patients with severe hypercapnia matched for all other variables, ventilation with PLS was associated with higher ICU mortality (OR 1.58, CI 95% 1.04-2.41; p = 0.032). CONCLUSIONS: Severe hypercapnia appears to be independently associated with higher ICU mortality in patients with ARDS. TRIAL REGISTRATION: Clinicaltrials.gov identifier, NCT01093482.

Impact of sedation and analgesia during noninvasive positive pressure ventilation on outcome: a marginal structural model causal analysis.

PURPOSE: There are limited data available about the role of sedation and analgesia during noninvasive positive pressure ventilation (NPPV). The objective of study was to estimate the effect of analgesic or sedative drugs on the failure of NPPV. METHODS: We studied patients who received at least 2 h of NPPV as first-line therapy in a prospective observational study carried out in 322 intensive care units from 30 countries. A marginal structural model (MSM) was used to analyze the association between the use of analgesic or sedative drugs and NPPV failure (defined as need for invasive mechanical ventilation). RESULTS: 842 patients were included in the analysis. Of these, 165 patients (19.6%) received analgesic or sedative drugs at some time during NPPV; 33 of them received both. In the adjusted analysis, the use of analgesics (odds ratio 1.8, 95% confidence interval 0.6-5.4) or sedatives (odds ratio 2.8, 95% CI 0.85-9.4) alone was not associated with NPPV failure, but their combined use was associated with failure (odds ratio 5.7, 95% CI 1.8-18.4). CONCLUSIONS: Slightly less than 20% of patients received analgesic or sedative drugs during NPPV, with no apparent effect on outcome when used alone. However, the simultaneous use of analgesics and sedatives may be associated with failure of NPPV.

Evolution of mortality over time in patients receiving mechanical ventilation.

RATIONALE: Baseline characteristics and management have changed over time in patients requiring mechanical ventilation; however, the impact of these changes on patient outcomes is unclear. OBJECTIVES: To estimate whether mortality in mechanically ventilated patients has changed over time. METHODS: Prospective cohort studies conducted in 1998, 2004, and 2010, including patients receiving mechanical ventilation for more than 12 hours in a 1-month period, from 927 units in 40 countries. To examine effects over time on mortality in intensive care units, we performed generalized estimating equation models. MEASUREMENTS AND MAIN RESULTS: We included 18,302 patients. The reasons for initiating mechanical ventilation varied significantly among cohorts. Ventilatory management changed over time (P < 0.001), with increased use of noninvasive positive-pressure ventilation (5% in 1998 to 14% in 2010), a decrease in tidal volume (mean 8.8 ml/kg actual body weight [SD = 2.1] in 1998 to 6.9 ml/kg [SD = 1.9] in 2010), and an increase in applied positive end-expiratory pressure (mean 4.2 cm H2O [SD = 3.8] in 1998 to 7.0 cm of H2O [SD = 3.0] in 2010). Crude mortality in the intensive care unit decreased in 2010 compared with 1998 (28 versus 31%; odds ratio, 0.87; 95% confidence interval, 0.80-0.94), despite a similar complication rate. Hospital mortality decreased similarly. After adjusting for baseline and management variables, this difference remained significant (odds ratio, 0.78; 95% confidence interval, 0.67-0.92). CONCLUSIONS: Patient characteristics and ventilation practices have changed over time, and outcomes of mechanically ventilated patients have improved. Clinical trials registered with www.clinicaltrials.gov (NCT01093482).

Calidad de atención médica y principios / Qualidade de atenção médica e principios éticos / Health care quality and ethical principles

La calidad en la atención se ha transformado en un requisito fundamental de todo servicio sanitario. A pesar del extraordinario desarrollo científico-tecnológico logrado en las últimas décadas, la complejidad de los servicios de salud ha hecho que se incrementen los errores médicos con consecuencias muy negativas en la morbilidad, mortalidad y costos de atención. Han surgido diferentes modelos de calidad de atención. Sin embargo, por lo general estos se implementan como procesos administrativos, gerenciales y alejados de la realidad del personal que los debe utilizar. La calidad de atención debe ser percibida no sólo como un problema médico gerencial, sino como un problema moral y, como tal, estar sustentado en una educación en valores que garantice la participación activa de todos los actores del sistema, siendo la excelencia, la solidaridad y el profesionalismo valores fundamentales.

Health care quality has become a fundamental requirement for any health care service. Despite the extraordinary scientific-technological development achieved in the last decades, the complexity of health care services provokes the increase of medical errors with very negative consequences in morbidity, mortality and health care costs. Several health care quality models have been raised. Nevertheless, in general these are implemented as administrative, management processes far from the actual work of staff which must use them. Health care quality must not be perceived only as medical management problem, but as an ethical problem and, as such, it must be based on education on values which guarantee active participation of all stakeholders, being excellence, solidarity and professionalism fundamental values.

A qualidade na atenção transformou-se num requisito fundamental de todo serviço sanitário. Apesar do extraordinário desenvolvimento científico-tecnológico logrado nas últimas décadas, a complexidade dos serviços de saúde faz com que se incrementem os erros médicos com consequências muito negativas na morbilidade, mortalidade e custos de atenção. Têm surgido diferentes modelos de qualidade de atenção. Entretanto, em geral estes se implementam como processos administrativos, gerenciais, afastados da realidade do pessoal que deve utilizá-los. A qualidade de atenção deve ser percebida não somente como um problema médico gerencial, senão como um problema moral e, como tal, deve estar sustentada numa educação de valores que garanta a participação ativa de todos os atores do sistema, sendo a excelência, a solidariedade e o profissionalismo os seus valores fundamentais.

La etica de la indicación médica / The ethics of medical recomendation

La incitación médica es parte de la rutina del acto médico, sin embargo, poco se habla de la responsabilidad moral y legal que el médico asume cada vez que prescribe un tratamiento o un método diagnóstico. Diferentes factores han contribuido a hacer cada vez más conpleja la sección y ejecución de una indicación correcta. En forma paradójica la mayor disponibilidad de recursos tecnológicos para el diagnóstico y tratamiento han contribuido a hacer mucho más dificil la decisión sobre la mejor manera de hacerle un bien al enfermo. A esto se suma el incremento en las posibilidades de errores, debidos a la complejidad de los sistemas de atención médica; las dificultades para llevar a cabo una adecuada relación médico paciente que garantice el respecto a los valores, la dignidad y los derechos de las personas y; finalmente, las dificultades relacionadas con la adecuada gestión de los costos de atención médica. En este artículo se revisarán las diferentes causas que dificultaran una correcta selección de la indicación y su relación con los principios de la bioética.

A medical recommendation is a part of the routine of a medical act, however, there is little discussion of the moral and legal responsibilities that a physician assumes each time a treatment or a diagnostic test is called for. Various factors are contributing to the increasing complexity of the selection and implementation of a correct recomendation. Paradoxically the increased availability of technological resources for diagnosis and treatment has contributed to the difficulty of making decision on how best to benefit the patient. Furthermore there are increased changes of errors, due to the complexity of systems of care; difficulties in carrying out a proper doctor-patient relationship, ensuring respect for values, dignity and individual right and; finally, difficulties related to the proper management of health care costs. In this article we review the various factors that make the correct choice of a medical recommendation difficult and how that relates to bioethical principles.

Que es bioética? / What is bioethic?

El desarrollo de la ciencia y la tecnología han cambiado nuestra forma de vivir y nuestra concepción de la vida. Este desarrollo ha tenido repercusiones muy positivas, pero a la vez, han surgido serios problemas éticos que debemos conocer y enfrentar. Hoy sabemos que los efectos negativos sobre el medio ambiente derivados del uso de la biotecnología, ponen en peligro la subsistencia de la vida en el planeta. En el campo específico de la medicina; han surgido serias dificultades para la adecuada selección de las indicaciones médicas; se ha creado un importante abismo entre el conocimiento que hoy tenemos y la aplicación de estos conocimientos en la práctica clínica; se han incrementado los errores, los costos y la inequidad en la atención médica. Existen serias dudas en relación con el uso de las nuevas técnicas de fertilización. A la vez que en muchas ocasiones no sabemos si debemos tratar o no tratar ciertos pacientes con enfermedades en etapa terminal o en situaciones que los dejarían con serias incapacidades físicas y mentales. La cardiología ha sido una de las especialidades más beneficiadas con el desarrollo científico-tecnológico, lo cual sin dudas ha tenido repercusiones muy positivas, y en consecuencia, también enfrenta importantes problemas éticos. La bioética constituye un espacio la reflexión, deliberación y búsqueda de las mejores soluciones a los problemas éticos surgidos del desarrollo y aplicación de la biotecnología, desde una perspectiva plural y orientada a un diálogo por la vida y el respeto a la dignidad y derechos del ser humano.

Developments in science and technology have changed aur way of life and aur understanding of life. These developments have had a very positive impact, but at the same time, serious ethical problems have arisen that we have to understand and face. We know today that negative effects on the environment arising from the use of biotechnology, endanger the survival of life on the planet. Specifically in medicine, serious difficulties have arisen for the proper selection of medical applications; a significant gap has arisen between the knowledge we have today and the application of knowledge in clinical practice; there is an increase in errors, expenditures and inequity in health care. There are serious doubts about the use of new fertility techniques. There are times when we do not know whether or to treat certain patients with end-stage disease particulary in situations that would leave them with serious physical and mental disabilities. Cardiology has been one of the speciclties which has benefited from scientific and technological development, which has ubdoubtedly had a very positive impact, and consequently it also faces important ethical challenges. Bioethics creates room for reflection, debate and a search fot the best solutions to the ethical problems arising from the development and application of biotechnology, from a pluralistic perspective to a dialogue aimed at dignity and human rights.

Bioética e investigación científica / Bioethics and scientific research

La investigación científica ha constituido a lo largo de la historia una de las vías fundamentales del desarrollo de la humanidad. En el campo específico de la medicina, la investigación ha sido una fuente permanente de conocimientos, los cuales han permitido el desarrollo de un extraordinario arsenal de métodos de diagnóstico y tratamiento, que nos permiten hoy diagnosticar y tratar pacientes con enfermedades, que hasta hace poco tiempo, resultaba imposible resolver o al menos aliviar. Vale la pena destacar que la investigación no sólo aporta conocimientos, es además la vía para la validación de estos conocimientos... Dentro de la concepción ética de la práctica clínica actual, tener el conocimiento no es suficiente para su utilización en los enfermos, se requiere que este conocimiento sea científicamente válido de forma que se demuestre su utilidad.

Evolution of mechanical ventilation in response to clinical research.

RATIONALE: Recent literature in mechanical ventilation includes strong evidence from randomized trials. Little information is available regarding the influence of these trials on usual clinical practice. OBJECTIVES: To describe current mechanical ventilation practices and to assess the influence of interval randomized trials when compared with findings from a 1998 cohort. METHODS: A prospective international observational cohort study, with a nested comparative study performed in 349 intensive care units in 23 countries. We enrolled 4,968 consecutive patients receiving mechanical ventilation over a 1-month period. We recorded demographics and daily data related to mechanical ventilation for the duration of ventilation. We systematically reviewed the literature and developed 11 practice-change hypotheses for the comparative cohort study before seeing these results. In assessing practice changes, we only compared data from the 107 intensive care units (1,675 patients) that also participated in the 1998 cohort (1,383 patients). MEASUREMENTS AND MAIN RESULTS: In 2004 compared with 1998, the use of noninvasive ventilation increased (11.1 vs. 4.4%, P < 0.001). Among patients with acute respiratory distress syndrome, tidal volumes decreased (7.4 vs. 9.1 ml/kg, P < 0.001) and positive end-expiratory pressure levels increased slightly (8.7 vs. 7.7 cm H(2)O, P = 0.02). More patients were successfully extubated after their first attempt of spontaneous breathing (77 vs. 62%, P < 0.001). Use of synchronized intermittent mandatory ventilation fell dramatically (1.6 vs. 11%, P < 0.001). Observations confirmed 10 of our 11 practice-change hypotheses. CONCLUSIONS: The strong concordance of predicted and observed practice changes suggests that randomized trial results have advanced mechanical ventilation practices internationally.

Risk factors for extubation failure in patients following a successful spontaneous breathing trial.

BACKGROUND: To assess the factors associated with reintubation in patients who had successfully passed a spontaneous breathing trial. METHODS: We used logistic regression and recursive partitioning analyses of prospectively collected clinical data from adults admitted to ICUs of 37 hospitals in eight countries, who had undergone invasive mechanical ventilation for > 48 h and were deemed ready for extubation. RESULTS: Extubation failure occurred in 121 of the 900 patients (13.4%). The logistic regression analysis identified the following associations with reintubation: rapid shallow breathing index (RSBI) [odds ratio (OR), 1.009 per unit; 95% confidence interval (CI), 1.003 to 1.015]; positive fluid balance (OR, 1.70; 95% CI, 1.15 to 2.53); and pneumonia as the reason for initiating mechanical ventilation (OR, 1.77; 95% CI, 1.10 to 2.84). The recursive partitioning analysis allowed the separation of patients into different risk groups for extubation failure: (1) RSBI of > 57 breaths/L/min and positive fluid balance (OR, 3.0; 95% CI, 1.8 to 4.8); (2) RSBI of < 57 breaths/L/min and pneumonia as reason for mechanical ventilation (OR, 2.0; 95% CI, 1.1 to 3.6); (3) RSBI of > 57 breaths/L/min and negative fluid balance (OR, 1.4; 95% CI, 0.8 to 2.5); and (4) RSBI of < 57 breaths/L/min (OR, 1 [reference value]). CONCLUSIONS: Among routinely measured clinical variables, RSBI, positive fluid balance 24 h prior to extubation, and pneumonia at the initiation of ventilation were the best predictors of extubation failure. However, the combined predictive ability of these variables was weak.

Incidence, risk factors, and outcome of ventilator-associated pneumonia.

OBJECTIVE: The purpose of this study is to determine the incidence, risk factors, and outcome of ventilator-associated pneumonia (VAP). DESIGN: Prospective cohort. SETTING: Three hundred sixty-one intensive care units (ICUs) from 20 countries. PATIENTS AND PARTICIPANTS: Two thousand eight hundred ninety-seven patients mechanically ventilated for more than 12 hours. MEASUREMENTS AND RESULTS: Baseline demographic data, primary indication for mechanical ventilation, daily ventilator settings, multiple organ failure over the course of mechanical ventilation, and outcome were collected. Ventilator-associated pneumonia was present in 439 patients (15%). Patients with VAP were more likely to have chronic pulmonary obstructive disease, aspiration, sepsis, and acute respiratory distress syndrome. Mortality in patients with VAP was 38%. Factors associated with mortality were severity of illness, limited activity before the onset of mechanical ventilation and development of shock, acute renal failure, and worsening of hypoxemia during the period of mechanical ventilation. Case-control analysis showed no increased mortality in patients with VAP (38.1% vs 37.9%, P = .95) but prolonged duration of mechanical ventilation and ICU stay. CONCLUSION: In a large cohort of mechanically ventilated patients, VAP is more likely in patients with underlying lung disease (acute or chronic). Ventilator-associated pneumonia was associated with a significant increase in ICU length of stay but no increase in mortality.

Outcome of mechanically ventilated patients who require a tracheostomy.

OBJECTIVE: To estimate the prevalence of, the risk factors associated with, and the outcome of tracheostomy in a heterogeneous population of mechanically ventilated patients. DESIGN: Prospective, observational cohort study. SETTING: A total of 361 intensive care units from 12 countries. PATIENTS: A cohort of 5,081 patients mechanically ventilated for >12 hrs. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: A total of 546 patients (10.7%) had a tracheostomy during their stay in the intensive care unit. Tracheostomy was performed at a median time of 12 days (interquartile range, 7-17) from the beginning of mechanical ventilation. Variables associated with the performance of tracheostomy were duration of mechanical ventilation, need for reintubation, and neurologic disease as the primary reason of mechanical ventilation. The intensive care unit stay of patients with or without tracheostomy was a median of 21 days (interquartile range, 12-32) vs. 7 days (interquartile range, 4-12; p < .001), respectively, and the hospital stay was a median 36 days (interquartile range, 23-53) vs. 15 days (interquartile range, 8-26; p < .001), respectively. Adjusting by other variables, tracheostomy was independently related with survival in the intensive care unit (odds ratio, 2.22; 95% confidence interval, 1.72-2.86). Mortality in the hospital was similar in both groups (39% vs. 40%, p = .65). CONCLUSIONS: Tracheostomy is a common surgical procedure in the intensive care unit that is associated with a lower mortality in the unit but with a longer stay and a similar mortality in the hospital than in patients without tracheostomy.

Noninvasive positive-pressure ventilation for respiratory failure after extubation.

BACKGROUND: The need for reintubation after extubation and discontinuation of mechanical ventilation is not uncommon and is associated with increased mortality. Noninvasive positive-pressure ventilation has been suggested as a promising therapy for patients with respiratory failure after extubation, but a single-center, randomized trial recently found no benefit. We conducted a multicenter, randomized trial to evaluate the effect of noninvasive positive-pressure ventilation on mortality in this clinical setting. METHODS: Patients in 37 centers in eight countries who were electively extubated after at least 48 hours of mechanical ventilation and who had respiratory failure within the subsequent 48 hours were randomly assigned to either noninvasive positive-pressure ventilation by face mask or standard medical therapy. RESULTS: A total of 221 patients with similar baseline characteristics had been randomly assigned to either noninvasive ventilation (114 patients) or standard medical therapy (107 patients) when the trial was stopped early, after an interim analysis. There was no difference between the noninvasive-ventilation group and the standard-therapy group in the need for reintubation (rate of reintubation, 48 percent in both groups; relative risk in the noninvasive-ventilation group, 0.99; 95 percent confidence interval, 0.76 to 1.30). The rate of death in the intensive care unit was higher in the noninvasive-ventilation group than in the standard-therapy group (25 percent vs. 14 percent; relative risk, 1.78; 95 percent confidence interval, 1.03 to 3.20; P=0.048), and the median time from respiratory failure to reintubation was longer in the noninvasive-ventilation group (12 hours vs. 2 hours 30 minutes, P=0.02). CONCLUSIONS: Noninvasive positive-pressure ventilation does not prevent the need for reintubation or reduce mortality in unselected patients who have respiratory failure after extubation.

Incidence, risk factors and outcome of barotrauma in mechanically ventilated patients.

OBJECTIVE: To determine the incidence, risk factors, and outcome of barotrauma in a cohort of mechanically ventilated patients where limited tidal volumes and airway pressures were used. DESIGN AND SETTING: Prospective cohort of 361 intensive care units from 20 countries. PATIENTS AND PARTICIPANTS: A total of 5183 patients mechanically ventilated for more than 12 h. MEASUREMENTS AND RESULTS: Baseline demographic data, primary indication for mechanical ventilation, daily ventilator settings, multiple-organ failure over the course of mechanical ventilation and outcome were collected. Barotrauma was present in 154 patients (2.9%). The incidence varied according to the reason for mechanical ventilation: 2.9% of patients with chronic obstructive pulmonary disease; 6.3% of patients with asthma; 10.0% of patients with chronic interstitial lung disease (ILD); 6.5% of patients with acute respiratory distress syndrome (ARDS); and 4.2% of patients with pneumonia. Patients with and without barotrauma did not differ in any ventilator parameter. Logistic regression analysis identified as factors independently associated with barotrauma: asthma [RR 2.58 (1.05-6.50)], ILD [RR 4.23 (95%CI 1.78-10.03)]; ARDS as primary reason for mechanical ventilation [RR 2.70 (95%CI 1.55-4.70)]; and ARDS as a complication during the course of mechanical ventilation [RR 2.53 (95%CI 1.40-4.57)]. Case-control analysis showed increased mortality in patients with barotrauma (51.4 vs 39.2%; p=0.04) and prolonged ICU stay. CONCLUSIONS: In a cohort of patients in whom airway pressures and tidal volume are limited, barotrauma is more likely in patients ventilated due to underlying lung disease (acute or chronic). Barotrauma was also associated with a significant increase in the ICU length of stay and mortality.

Complicaciones del uso de balon de contrapulsación intra-aórtico: a propósito de un caso clínico / Complications of the use of ball of contrapulsation aortic-intra: a porpuse of clinical case

La utilización de medidas terapéuticas, en pacientes hermodinámicamente inestables debe ser temprana y agresiva en vista del inminente compromiso de la vida. Estos tratamientos tales como el uso de drogas inotrópicas y el balón de contrapulsación intra-aórtico el cual es una forma de soporte circulatorio mecánico, mejoran la evolución de estos casos pero como todo procedimiento, llevan implícito la posibilidad de complicaciones que hay que considerar ya que posteriormente podrían aumentar la morbilidad y mortalidad de estos pacientes