Respiratory complications in the postanesthesia care unit: A review of pathophysiological mechanisms

Surgical, anesthetic and patient variables have been shown to impact pulmonary function in the postanesthesia period and contribute to complications in the postanesthesia care unit (PACU), with pulmonary atelectasis a common finding in more than 80% of anesthetized individuals. This comprehensive review discusses the major mechanisms causing deterioration of gas exchange in the immediate postoperative period; differential diagnosis of arterial hypoxemia in the PACU; preventive measures and treatment strategies for atelectasis; and the role of continuous positive airway pressure in the PACU

Noninvasive mechanical ventilation in high-risk pulmonary infections: a clinical review

The aim of this article was to review the role of noninvasive ventilation (NIV) in acute pulmonary infectious diseases, such as severe acute respiratory syndrome (SARS), H1N1 and tuberculosis, and to assess the risk of disease transmission with the use of NIV from patients to healthcare workers. We performed a clinical review by searching Medline and EMBASE. These databases were searched for articles on "clinical trials" and "randomised controlled trials". The keywords selected were non-invasive ventilation pulmonary infections, influenza-A (H1N1), SARS and tuberculosis. These terms were cross-referenced with the following keywords: health care workers, airborne infections, complications, intensive care unit and pandemic. The members of the International NIV Network examined the major results regarding NIV applications and SARS, H1N1 and tuberculosis. Cross-referencing mechanical ventilation with SARS yielded 76 studies, of which 10 studies involved the use of NIV and five were ultimately selected for inclusion in this review. Cross-referencing with H1N1 yielded 275 studies, of which 27 involved NIV. Of these, 22 were selected for review. Cross-referencing with tuberculosis yielded 285 studies, of which 15 involved NIV and from these seven were selected. In total 34 studies were selected for this review. NIV, when applied early in selected patients with SARS, H1N1 and acute pulmonary tuberculosis infections, can reverse respiratory failure. There are only a few reports of infectious disease transmission among healthcare workers

Non-invasive ventilation in patients with an altered level of consciousness. A clinical review and practical insights

Non-invasive ventilation has gained an increasingly pivotal role in the treatment of acute hypoxemic and/or hypercapnic respira-tory failure and offers multiple advantages over invasive mechanical ventilation. Some of these advantages include the preserva-tion of airway defense mechanisms, a reduced need for sedation, and an avoidance of complications related to endotracheal intubation.Despite its advantages, non-invasive ventilation has some contraindications that include, among them, severe encephalopathy. In this review article, the rationale, evidence, and drawbacks of the use of noninvasive ventilation in the context of hypercapnic and non-hypercapnic patients with an altered level of consciousness are analyzed

The Use of Airway Pressure Release Ventilation and Open Lung Management for Improving the Outcome of Lung Procurement for Transplantation

Abstract One of the most difficult organs to procure for donation is the lung. A detailed understanding of the physiology of mechanical ventilation and its effect on donor lungs is needed to impact on the outcome of lung transplantation. An organized protocol for mechanical ventilation management of the organ donor using the Open Lung Model may positively affect the number of organs that can be procured, and the function of these organs post transplant. Based on physiologic principles, the use of new modes of ventilation may affect the modulation of cytokines, decrease the transmigration of organisms into the donor lung, and preserve surfactant function in that lung. Therefore, we have developed a protocol guided by physiologic-based parameters and airway pressure release ventilation (APRV), with ongoing feedback from an advanced respiratory care team to manage donor patients closely. Setting: 650 bed university hospital and transplant center. Conclusion: We have developed a physiologic-based protocol, using APRV to achieve lung procurement that can decrease peak pressures and recruit the lungs using less and simultaneouslyincreasing the PaO 2 while using lower FIO 2 . This protocol may preserve surfactant function and assist during postoperative management. Additionally, this management mode may protect the donor organs from physiologic decay and evenimprove the outcomes. Further studies to measure long-term outcome need to be developed to validate physiologically based mechanical ventilation

Opening up to lung recruitment pulmonary contusion and derecruitment - The role of inflammation

Purpose of review: It was recently reported that a lung protective ventilation strategy resulted in no fatalities in 17 patients with ARDS secondary to lung contusion. Although the efficacy of a lung protective ventilation strategy to reduce mortality in ARDS patients has been demonstrated, the underlying mechanisms for this reduction remain unclear. Recent findings: ARDS is characterized by an inflammatory state of the lung that can be aggravated by mechanical ventilation. Especially mechanical ventilation allowing cyclic opening and closing of unstable alveoli, enhances cytokine release and can even result in loss of compartmentalization. Disbalance in the cytokine response can promote bacterial colonization and result in multiorgan failure. Recent clinical trials and experimental studies have demonstrated that recruitment of collapsed alveoli and stabilization of alveoli using sufficient levels of PEEP can reduce inflammation, bacterial colonization and the number of failing organs, thereby decreasing mortality. Summary: Lung protecti ve ventilation strategies minimizing this cyclic opening and closing by recruiting collapsed alveoli and subsequent stabilization with adequate levels of PEEP offer the clinician a tool to improve patient outcome in ARDS. This benefit is partly mediated by maintaining a 'natural' balance in the cytokine response. Future studies should explore this strategy in a randomized prospective study