Mechanical ventilation in Spain, 1998-2016: Changes in the disconnection of mechanical ventilation.

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.

Aggressive alveolar recruitment in ARDS: More shadows than lights.

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.

Mechanical ventilation in Spain, 1998-2016: changes in the disconnection of mechanical ventilation. / Ventilación mecánica en España, 1998-2016: cambios en la desconexión de la ventilación mecánica.

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.

Mechanical ventilation in Spain, 1998-2016: Epidemiology and outcomes. / Ventilación mecánica en España, 1998-2016: epidemiología y desenlaces.

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.

Physiological effects of adding ECCO2R to invasive mechanical ventilation for COPD exacerbations.

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.

High flow nasal cannula compared with conventional oxygen therapy for acute hypoxemic respiratory failure: a systematic review and meta-analysis.

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.

[Arterial Hypertension register in private clinics in Venezuela: RHAVEN Study]. / Registro de Hipertensión Arterial en consultas privadas en Venezuela: Estudio RHAVEN.

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%.

An Official American Thoracic Society/European Society of Intensive Care Medicine/Society of Critical Care Medicine Clinical Practice Guideline: Mechanical Ventilation in Adult Patients with Acute Respiratory Distress Syndrome

BACKGROUND: This document provides evidence-based clinical practice guidelines on the use of mechanical ventilation in adult patients with acute respiratory distress syndrome (ARDS). METHODS: A multidisciplinary panel conducted systematic reviews and metaanalyses of the relevant research and applied Grading of Recommendations, Assessment, Development, and Evaluation methodology for clinical recommendations. RESULTS: For all patients with ARDS, the recommendation is strong for mechanical ventilation using lower tidal volumes (4-8 ml/kg predicted body weight) and lower inspiratory pressures (plateau pressure < 30 cm H2O) (moderate confidence in effect estimates). For patients with severe ARDS, the recommendation is strong for prone positioning for more than 12 h/d (moderate confidence in effect estimates). For patients with moderate or severe ARDS, the recommendation is strong against routine use of high-frequency oscillatory ventilation (high confidence in effect estimates) and conditional for higher positive end-expiratory pressure (moderate confidence in effect estimates) and recruitment maneuvers (low confidence in effect estimates). Additional evidence is necessary to make a definitive recommendation for or against the use of extracorporeal membrane oxygenation in patients with severe ARDS. CONCLUSIONS: The panel formulated and provided the rationale for recommendations on selected ventilatory interventions for adult patients with ARDS. Clinicians managing patients with ARDS should personalize decisions for their patients, particularly regarding the conditional recommendations in this guideline.

[Treatment of pediatric lithiasis in the lithotripsy and endourology unit of "Hospital La Luz". Commented retrospective of our case series]. / Tratamiento de la litiasis en niños durante 30 años en la Unidad de Litotricia y Endourología del "Hospital La Luz". Retrospectiva comentada de nuestra casuística.

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.

Diastolic dysfunction in the critically ill patient.

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.

[Evaluation of pain during mobilization and endotracheal aspiration in critical patients]. / Evaluación del dolor durante la movilización y la aspiración endotraqueal en pacientes críticos.

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.

How to define nativeness in vagile organisms: lessons from the cosmopolitan moss Bryum argenteum on the island of Tenerife (Canary Islands).

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.

[Pressure support ventilation and proportional assist ventilation during weaning from mechanical ventilation]. / Ventilación con presión de soporte y ventilación proporcional asistida durante la retirada de la ventilación mecánica.

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.

The future of intensive care medicine.

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.

The semi-seated position slightly reduces the effort to breathe during difficult weaning.

PURPOSE: The influence of posture on breathing effort in patients with difficult weaning is unknown. We hypothesized that posture could modulate the breathing effort in difficult-to-wean patients. METHODS: A prospective, crossover, physiologic study was performed in 24 intubated patients breathing with pressure support who had already failed a spontaneous breathing trial or an extubation episode. Their median duration of mechanical ventilation before measurements was 25 days. Breathing pattern, occlusion pressure (P (0.1)), intrinsic PEEP (PEEP(i)), and inspiratory muscle effort evaluated by the pressure-time product of the respiratory muscles and the work of breathing were measured during three postures: the seated position in bed (90°LD), simulating the position in a chair, the semi-seated (45°), and the supine (0°) positions consecutively applied in a random order. A comfort score was obtained in 17 cooperative patients. The influence of position on chest wall compliance was measured in another group of 11 sedated patients. RESULTS: The 45° position was associated with the lowest levels of effort (p ≤ 0.01) and occlusion pressure (p < 0.05), and tended to be more often comfortable. Respiratory effort was the lowest at 45° in 18/24 patients. PEEP(i) and PEEP(i)-related work were slightly higher in the supine position (p ≤ 0.01), whereas respiratory effort, heart rate, and P (0.1) values were increased in the seated position (p < 0.05). CONCLUSION: A 45° position helps to unload the respiratory muscles, moderately reduces PEEP(i), and is often considered as comfortable. The semi-seated position may help the weaning process in ventilator-dependent patients.

[Hemodynamic and antipyretic effects of paracetamol, metamizol and dexketoprofen in critical patients]. / Efectos hemodinámicos y antipiréticos del paracetamol, metamizol y dexketoprofeno en pacientes críticos.

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.