Nebulized Heparin For Patients Under Mechanical Ventilation: An Individual Patient Data Meta-Analysis

Pulmonary coagulopathy is a characteristic feature of lung injury including ventilator-induced lung injury. The aim of this individual patient data meta-analysis is to assess the effects of nebulized anticoagulants on outcome of ventilated intensive care unit (ICU) patients. A systematic search of PubMed (1966–2014), Scopus, EMBASE, and Web of Science was conducted to identify relevant publications. Studies evaluating nebulization of anticoagulants in ventilated patients were screened for inclusion, and corresponding authors of included studies were contacted to provide individual patient data. The primary endpoint was the number of ventilator-free days and alive at day 28. Secondary endpoints included hospital mortality, ICU- and hospital-free days at day 28, and lung injury scores at day seven. We constructed a propensity score-matched cohort for comparisons between patients treated with nebulized anticoagulants and controls. Data from five studies (one randomized controlled trial, one open label study, and three studies using historical controls) were included in the meta-analysis, compassing 286 patients. In all studies unfractionated heparin was used as anticoagulant. The number of ventilator-free days and alive at day 28 was higher in patients treated with nebulized heparin compared to patients in the control group (14 [IQR 0–23] vs. 6 [IQR 0–22]), though the difference did not reach statistical significance (P = 0.459). The number of ICU-free days and alive at day 28 was significantly higher, and the lung injury scores at day seven were significantly lower in patients treated with nebulized heparin. In the propensity score-matched analysis, there were no differences in any of the endpoints. This individual patient data meta-analysis provides no convincing evidence for benefit of heparin nebulization in intubated and ventilated ICU patients. The small patient numbers and methodological shortcomings of included studies underline the need for high-quality well-powered randomized controlled trials

Nebulized heparin in burn patients with inhalation trauma : safety and feasibility

Background: Pulmonary hypercoagulopathy is intrinsic to inhalation trauma. Nebulized heparin could theoretically be beneficial in patients with inhalation injury, but current data are conflicting. We aimed to investigate the safety, feasibility, and effectiveness of nebulized heparin. Methods: International multicenter, double-blind, placebo-controlled randomized clinical trial in specialized burn care centers. Adult patients with inhalation trauma received nebulizations of unfractionated heparin (25,000 international unit (IU), 5 mL) or placebo (0.9% NaCl, 5 mL) every four hours for 14 days or until extubation. The primary outcome was the number of ventilator-free days at day 28 post-admission. Here, we report on the secondary outcomes related to safety and feasibility. Results: The study was prematurely stopped after inclusion of 13 patients (heparin N = 7, placebo N = 6) due to low recruitment and high costs associated with the trial medication. Therefore, no analyses on effectiveness were performed. In the heparin group, serious respiratory problems occurred due to saturation of the expiratory filter following nebulizations. In total, 129 out of 427 scheduled nebulizations were withheld in the heparin group (in 3 patients) and 45 out of 299 scheduled nebulizations were withheld in the placebo group (in 2 patients). Blood-stained sputum or expected increased bleeding risks were the most frequent reasons to withhold nebulizations. Conclusion: In this prematurely stopped trial, we encountered important safety and feasibility issues related to frequent heparin nebulizations in burn patients with inhalation trauma. This should be taken into account when heparin nebulizations are considered in these patients

Transesophageal Versus Surface Electromyography of the Diaphragm in Ventilated Subjects

BACKGROUND: Detection of diaphragmatic muscle activity during invasive ventilation may provide valuable information about patient-ventilator interactions. Transesophageal electromyography of the diaphragm (tEA di ) is used in neurally adjusted ventilatory assist. This technique is invasive and can only be applied with one specific ventilator. Surface electromyography of the diaphragm (sEA di ) is noninvasive and can potentially be applied with all types of ventilators. The primary objective of our study was to compare the ability of diaphragm activity detection between sEA di and tEA di . METHODS: In this single-center pilot study, sEA di and tEA di recordings were obtained simultaneously for 15 min in adult subjects in the ICU who were invasively ventilated. The number of breathing efforts detected by sEA di and tEA di were determined. The percentage of detected breathing efforts by sEA di compared with tEA di was calculated. Temporal and signal strength relations on optimum recordings of 10 breaths per subject were also compared. The Spearman correlation coefficient was used to determine the correlation between sEA di and tEA di . Agreement was calculated by using Bland-Altman statistics. RESULTS: Fifteen subjects were included. The tEA di detected 3,675 breathing efforts, of which 3,162 (86.0%) were also detected by sEA di . A statistically significant temporal correlation (r 5 0.95, P < .001) was found between sEA di and tEA di in stable recordings. The mean difference in the time intervals between both techniques was 10.1 ms, with limits of agreement from – 410 to 430 ms. CONCLUSIONS: Analysis of our results showed that sEA di was not reliable for breathing effort detection in subjects who were invasively ventilated compared with tEA di .Instable recordings, however, sEA di and tEA di had excellent temporal correlation and good agreement. With optimization of signal stability, sEA di may become a useful monitoring tool

HEPBURN - investigating the efficacy and safety of nebulized heparin versus placebo in burn patients with inhalation trauma: study protocol for a multi-center randomized controlled trial

Pulmonary coagulopathy is a hallmark of lung injury following inhalation trauma. Locally applied heparin attenuates lung injury in animal models of smoke inhalation. Whether local treatment with heparin benefits patients with inhalation trauma is uncertain. The present trial aims at comparing a strategy using frequent nebulizations of heparin with standard care in intubated and ventilated burn patients with bronchoscopically confirmed inhalation trauma. The Randomized Controlled Trial Investigating the Efficacy and Safety of Nebulized HEParin versus Placebo in BURN Patients with Inhalation Trauma (HEPBURN) is an international multi-center, double-blind, placebo-controlled, two-arm study. One hundred and sixteen intubated and ventilated burn patients with confirmed inhalation trauma are randomized to nebulizations of heparin (the nebulized heparin strategy) or nebulizations of normal saline (the control strategy) every four hours for 14 days or until extubation, whichever comes first. The primary endpoint is the number of ventilator-free days, defined as days alive and breathing without assistance during the first 28 days, if the period of unassisted breathing lasts for at least 24 consecutive hours. As far as the authors know, HEPBURN is the first randomized, placebo-controlled trial, powered to investigate whether local treatment with heparin shortens duration of ventilation of intubated and ventilated burn patients with inhalation trauma. NCT01773083 (http://www.clinicaltrials.gov), registered on 16 January 2013.Recruiting. Randomisation commenced on 1 January 201

Iron metabolism in critically ill patients developing anemia of inflammation: a case control study

Background: Anemia occurring as a result of inflammatory processes (anemia of inflammation, AI) has a high prevalence in critically ill patients. Knowledge on changes in iron metabolism during the course of AI is limited, hampering the development of strategies to counteract AI. This case control study aimed to investigate iron metabolism during the development of AI in critically ill patients. Methods: Iron metabolism in 30 patients who developed AI during ICU stay was compared with 30 septic patients with a high Hb and 30 non-septic patients with a high Hb. Patients were matched on age and sex. Longitudinally collected plasma samples were analyzed for levels of parameters of iron metabolism. A linear mixed model was used to assess the predictive values of the parameters. Results: In patients with AI, levels of iron, transferrin and transferrin saturation showed an early decrease compared to controls with a high Hb, already prior to the development of anemia. Ferritin, hepcidin and IL-6 levels were increased in AI compared to controls. During AI development, erythroferrone decreased. Differences in iron metabolism between groups were not influenced by APACHE IV score. Conclusions: The results show that in critically ill patients with AI, iron metabolism is already altered prior to the development of anemia. Levels of iron regulators in AI differ from septic controls with a high Hb, irrespective of disease severity. AI is characterized by high levels of hepcidin, ferritin and IL-6 and low levels of iron, transferrin and erythroferrone

Changes in ventilator settings and ventilation–induced lung injury in burn patients—A systematic review

Objective: Ventilation strategies aiming at prevention of ventilator–induced lung injury (VILI), including low tidal volumes (VT) and use of positive end–expiratory pressures (PEEP) are increasingly used in critically ill patients. It is uncertain whether ventilation practices changed in a similar way in burn patients. Our objective was to describe applied ventilator settings and their relation to development of VILI in burn patients. Data Sources: Systematic search of the literature in PubMed and EMBASE using MeSH, EMTREE terms and keywords referring to burn or inhalation injury and mechanical ventilation. Study selection: Studies reporting ventilator settings in adult or pediatric burn or inhalation injury patients receiving mechanical ventilation during the ICU stay. Data extraction: Two authors independently screened abstracts of identified studies for eligibility and performed data extraction. Data synthesis: The search identified 35 eligible studies. VT declined from 14 ml/kg in studies performed before to around 8 ml/kg predicted body weight in studies performed after 2006. Low-PEEP levels (<10 cmH2O) were reported in 70% of studies, with no changes over time. Peak inspiratory pressure (PIP) values above 35 cmH2O were frequently reported. Nevertheless, 75% of the studies conducted in the last decade used limited maximum airway pressures (≤35 cmH2O) compared to 45% of studies conducted prior to 2006. Occurrence of barotrauma, reported in 45% of the studies, ranged from 0 to 29%, and was more frequent in patients ventilated with higher compared to lower airway pressures. Conclusion: This systematic review shows noticeable trends of ventilatory management in burn patients that mirrors those in critically ill non-burn patients. Variability in available ventilator data precluded us from drawing firm conclusions on the association between ventilator settings and the occurrence of VILI in burn patients

Nebulized Heparin in Burn Patients with Inhalation Trauma-Safety and Feasibility

Background: Pulmonary hypercoagulopathy is intrinsic to inhalation trauma. Nebulized heparin could theoretically be beneficial in patients with inhalation injury, but current data are conflicting. We aimed to investigate the safety, feasibility, and effectiveness of nebulized heparin. Methods: International multicenter, double-blind, placebo-controlled randomized clinical trial in specialized burn care centers. Adult patients with inhalation trauma received nebulizations of unfractionated heparin (25,000 international unit (IU), 5 mL) or placebo (0.9% NaCl, 5 mL) every four hours for 14 days or until extubation. The primary outcome was the number of ventilator-free days at day 28 post-admission. Here, we report on the secondary outcomes related to safety and feasibility. Results: The study was prematurely stopped after inclusion of 13 patients (heparin N = 7, placebo N = 6) due to low recruitment and high costs associated with the trial medication. Therefore, no analyses on effectiveness were performed. In the heparin group, serious respiratory problems occurred due to saturation of the expiratory filter following nebulizations. In total, 129 out of 427 scheduled nebulizations were withheld in the heparin group (in 3 patients) and 45 out of 299 scheduled nebulizations were withheld in the placebo group (in 2 patients). Blood-stained sputum or expected increased bleeding risks were the most frequent reasons to withhold nebulizations. Conclusion: In this prematurely stopped trial, we encountered important safety and feasibility issues related to frequent heparin nebulizations in burn patients with inhalation trauma. This should be taken into account when heparin nebulizations are considered in these patients

Increased early systemic inflammation in ICU-acquired weakness: a prospective observational cohort study

To investigate whether patients who develop ICU-acquired weakness have a different pattern of systemic inflammatory markers compared with critically ill patients who do not develop ICU-acquired weakness. Prospective observational cohort study. Mixed medical-surgical ICU of a tertiary care hospital in the Netherlands. Newly admitted critically ill patients, greater than or equal to 48 hours on mechanical ventilation with a nonneurologic ICU admission diagnosis, were included. A panel of systemic inflammatory markers and soluble vascular adhesion molecules were measured in plasma samples of day 0, 2, and 4 after ICU admission. ICU-acquired weakness was diagnosed by manual muscle strength testing as soon as patients were awake and attentive. Ninety-nine of 204 included patients developed ICU-acquired weakness. Principal component regression analysis, adjusted for confounders, showed that principal component 1, mainly loaded with interleukin-6, interleukin-8, interleukin-10, and fractalkine, was significantly higher in patients who developed ICU-acquired weakness (odds ratio, 1.35 [95% CI, 1.18-1.55]). Partial least squares-discriminant analysis also showed that these markers were the most important discriminative markers. Mixed-effects models of these markers showed that ICU-acquired weakness was associated with an independent 1.5- to two-fold increase in these markers. Systemic inflammation is increased in patients who develop ICU-acquired weakness compared with patients who do not develop ICU-acquired weakness in the first 4 days after ICU admission. This finding is consistent when adjusted for confounders, like disease severity. A group consisting of interleukin-6, interleukin-8, interleukin-10, and fractalkine was identified to be the most importan