Protective mechanical ventilation with low tidal volume (Vt) and low plateau pressure reduces mortality and decreases the length of mechanical ventilation in patients with acute respiratory distress syndrome. Mechanical ventilation that will protect normal lungs during major surgical procedures of long duration may improve postoperative outcomes. We performed an animal study comparing 3 ventilation strategies used in the operating room in normal lungs. We compared the effects on pulmonary mechanics, inflammatory mediators, and lung tissue injury.
Female pigs were randomized into 3 groups. Group H-Vt/3 (n = 6) was ventilated with a Vt of 15 mL/kg predicted body weight (PBW)/positive end-expiratory pressure (PEEP) of 3 cm H(2)O, group L-Vt/3 (n = 6) with a Vt of 6 mL/kg PBW/PEEP of 3 cm H(2)O, and group L-Vt/10 (n = 6) with a Vt of 6 mL/kg PBW/PEEP of 10 cm H(2)O, for 8 hours. Hemodynamics, airway mechanics, arterial blood gases, and inflammatory markers were monitored. Bronchoalveolar lavage (BAL) was analyzed for inflammatory markers and protein concentration. The right lower lobe was assayed for mRNA of specific cytokines. The right lower lobe and right upper lobe were evaluated histologically.
In contrast to groups H-Vt/3 and L-Vt/3, group L-Vt/10 exhibited a 6-fold increase in inflammatory mediators in BAL (P < 0.001). Cytokines in BAL were similar in groups H-Vt/3 and L-Vt/3. Group H-Vt/3 had a significantly lower lung injury score than groups L-Vt/3 and L-Vt/10.
Comparing intraoperative strategies, ventilation with high PEEP resulted in increased production of inflammatory markers. Low PEEP resulted in lower levels of inflammatory markers. High Vt/low PEEP resulted in less histologic lung injury.
"Overall, a markedly reduced volume of lung is available for ventilation in ARDS (Oeckler and Hubmayr, 2007). Therefore, the manner in which mechanical ventilator support is applied has the potential to exacerbate lung injury further due to the application of TVs to the (reduced) area of non-consolidated alveoli (Hong et al., 2010) and the development of inflammatory mediators associated with large TV usage (Determann et al., 2010). This sort of evidence calls for ICU nurses and doctors to be aware of the risks that ARDS and non-ARDS patients undergo while they are mechanically ventilated. "
[Show abstract][Hide abstract] ABSTRACT: Background:
Adult respiratory distress syndrome (ARDS) is a type of acute diffuse lung injury characterized by severe inflammation, increased pulmonary vascular permeability and a loss of aerated lung tissue. The effects of high fraction of inspired oxygen (FiO2 ) include oxygen toxicity manifested by damage to the lung parenchyma in the acute phase of lung injury. There is still a high mortality rate among this group of patients, so clinically sensitive evidence-based interventions are paramount to maximize survival chances during critical care.
Aims and objectives:
The aim of this article is to explore the current opinion concerning optimal mechanical ventilation support techniques for patients with acute respiratory distress syndrome.
Search strategy, inclusion and exclusion criteria:
A literature search of clinical trials and observation studies, reviews, discussion papers, meta-analyses and clinical guidelines written in English up to 2015, derived from the databases of Scopus, CINAHL, Cochrane Library databases and PubMed was conducted.
Low tidal volume, pressure limitation and prone positioning in severe ARDS patients appear to be of some benefit. More research is required and further development and use of standardized protocols is an important strategy for reducing practice variations across disciplines, as well as giving clear guidelines to nurses practising in critical care. There is also evidence that this syndrome is under-diagnosed and the utilization of lung protective ventilation is still variable.
Relevance to clinical practice:
It is important that nurses have underlying knowledge of both aetiology of ARDS and ventilation management, and that they monitor patients very closely. The adoption of a low tidal ventilation protocol, which is based on quality evidence guidelines, the value of rescue therapies and patient observation practices in the overall patient management, and the need to place emphasis on long-term patient outcomes, all these emerge as key factors for consideration and future research. However, there is also a need for more research that would explore the unique contribution of nurses in the management of this patient group, as it is difficult to discern this in the current literature.
Nursing in Critical Care 10/2015; DOI:10.1111/nicc.12205 · 0.65 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Die mechanische Beatmung ist eine etablierte Methode in der Behandlung der respiratorischen Insuffizienz und ermöglicht die
Sicherstellung der Ventilation und Oxygenierung während einer Allgemeinanästhesie. Allgemeinanästhesie und mechanische Beatmung
führen zu relevanten Veränderungen der Ventilation, der pulmonalen Perfusion und des Gasaustausches. Verfahrensbedingt sind
mit der mechanischen Beatmung Risiken verbunden. Ein Risiko in der Behandlung von Patienten stellt der beatmungsassoziierte
Lungenschaden dar. Bei Patienten mit akutem Lungenversagen konnten durch die Anwendung einer lungenprotektiven Beatmungsstrategie
(Tidalvolumenreduktion und Limitierung des Beatmungsplateaudrucks) die Aktivität von Inflammationsmediatoren, die Beatmungsdauer
und der Endpunkt Mortalität positiv beeinflusst werden. Es existieren experimentelle Hinweise, dass die mechanische Beatmung
von gesunden Lungen gleichfalls Lungenschäden induziert; die klinische Relevanz dieser experimentellen Ergebnisse ist derzeit
unklar. Klinische Studien, die eine konventionelle Beatmung mit einer protektiven Beatmung während Allgemeinanästhesie auf
den Endpunkt pulmonale Inflammation verglichen haben, erbrachten inkonsistente Ergebnisse. Es existieren keine klinischen
Daten, die zeigen, dass die Translation des protektiven Beatmungskonzepts von Patienten mit akutem Lungenversagen auf die
Beatmung lungengesunder Patienten zu einem Vorteil hinsichtlich der Morbidität und Mortalität führt. Die Frage nach der optimalen
protektiven mechanischen Beatmung bei lungengesunden Patienten bleibt damit unbeantwortet.
General anesthesia and mechanical ventilation affect gas exchange, ventilation and pulmonary perfusion and there is an increasing
body of evidence that mechanical ventilation itself promotes lung injury. Lung protective mechanical ventilation in patients
suffering from acute lung injury or acute respiratory distress syndrome by means of reduced tidal volumes and limited plateau
pressures has been shown to result in reduction of systemic inflammatory mediators, increased ventilator-free days and reduction
in mortality. Experimental studies suggest that mechanical ventilation of uninjured lungs may also induce lung damage; however,
the clinical relevance remains unknown. Human prospective studies comparing mechanical ventilation strategies during general
anesthesia have shown inconsistent results with respect to inflammatory mediators. There is a lack of clinical evidence that
lung protective ventilation strategies as used in patients with lung injury may improve clinical outcome of patients with
uninjured lungs. The question of which ventilatory strategy will best protect normal human lungs remains unanswered.
SchlüsselwörterBeatmungsassoziierter Lungenschaden-Mechanische Beatmung-Allgemeinanästhesie-Lungenprotektive Beatmung
KeywordsVentilator-associated lung injury-Mechanical ventilation-General anesthesia-Lung protective mechanical ventilation
Der Anaesthesist 07/2010; 59(7):595-606. DOI:10.1007/s00101-010-1743-5 · 0.76 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The paper analyses the continuity, compatibility and inheritance of network evolution, points out the existence and complexity of second order information and gives an open intelligent integrated network management system model that can adapt to continuous network evolution. The author discusses design concerns, and analyses the interactions between the managing and managed entities within a network element which influence the network element evolution
TENCON '93. Proceedings. Computer, Communication, Control and Power Engineering.1993 IEEE Region 10 Conference on; 11/1993
Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.