Seminars in respiratory and critical care medicine
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Aspiration pneumonia (AP) remains a critical health issue, especially among older and hospitalized patients. This review focuses on understanding the epidemiology and pathogenesis of AP, exploring key risk factors, and proposing diagnostic strategies. Aspiration pneumonia is commonly associated with hospital-acquired pneumonia (HAP) and ventilator-associated pneumonia (VAP), where pathogens introduced into the lungs from gastric aspiration cause infection. ⋯ It is one of the most common types of pneumonia in older adults, with its prevalence estimated to range from 5% to 24% in cases of CAP admissions. This revision highlights the growing need for comprehensive diagnostic tools and treatment protocols for AP, especially in high-risk populations such as the elderly and those in long-term care. Understanding the underlying mechanisms and the role of silent aspiration can improve prevention strategies and reduce morbidity and mortality in these vulnerable groups.
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Semin Respir Crit Care Med · Dec 2024
ReviewTherapy of Aspiration: Out-of-Hospital and In-Hospital-Acquired.
Therapeutic considerations for aspiration pneumonia prioritize the risk of multidrug-resistant organisms. This involves integrating microbiological insights with each patient's unique risk profile, including the location at the time of aspiration, and whether it occurred in or out of the hospital. ⋯ This shift challenges the routine use of broad-spectrum antibiotics targeting anaerobes, which can contribute to antibiotic resistance and complications such as Clostridium difficile infections-concerns that are especially relevant given the growing issue of antimicrobial resistance. Adopting a comprehensive, patient-specific approach that incorporates these insights can optimize antibiotic selection, improve treatment outcomes, and reduce the risk of resistance and adverse effects.
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Semin Respir Crit Care Med · Dec 2024
ReviewBacteriology of Aspiration Pneumonia: The Lung Microbiome and the Changing Microbial Etiology.
Aspiration pneumonia refers to the process of alveolar inflammation induced by the inhalation of oropharyngeal secretions into the lower respiratory tract. Predisposing factors comprise swallowing dysfunction, impaired cough reflex, and degenerative neurological diseases. Accumulating evidence projects a fading contribution of anaerobic bacteria in aspiration pneumonia at the expense of Gram-negative bacilli, with Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa, becoming the predominant organisms recovered from respiratory specimens. ⋯ Understanding this complex temporal variability between microbiome-host associations was only made possible with the introduction of metagenomic sequencing. In this narrative review, we summarize existing knowledge and elaborate on the evolving microbiology of aspiration pneumonia including the link between oral microbiome and pulmonary aspiration. We also highlight the progress and challenges in instituting microbiome-targeted strategies for preventing and treating the sequelae of aspiration pneumonia.
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Semin Respir Crit Care Med · Dec 2024
ReviewPrevention of Aspiration: Oral Care, Antibiotics, Others.
Patients with aspiration pneumonia often develop this lung infection due to poor oral health or because the contents of the digestive tract or upper airway enter the lower airway traversing the larynx through different mechanisms. Prevention of this condition is directed at the mechanism by which it occurs. ⋯ People with dysphagia complicated by pneumonia have limited feeding and become debilitated, and aspiration pneumonia in these individuals has a high mortality rate at 90 days. Dietary modifications, assistance with feeding, use of postures that facilitate a normal deglutition, rehabilitation, and use of medications to improve swallowing defects are the tools of medicine to overcome the obstacles to swallowing normally and prevent the development of aspiration pneumonia and its consequences.
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Semin Respir Crit Care Med · Dec 2024
ReviewMedications to Modify Aspiration Risk: Those That Add to Risk and Those That May Reduce Risk.
Aspiration pneumonia results from the abnormal entry of fluids into the respiratory tract. We present a review of drugs known to affect the risk of aspiration. Drugs that increase the risk of aspiration pneumonia can be broadly divided into those that affect protective reflexes (like cough and swallowing) due to direct or indirect mechanisms, and drugs that facilitate gastric dysbiosis or affect esophageal and intestinal motility. ⋯ Focusing on modifiable risk factors for aspiration pneumonia is relevant since this may help to reduce the incidence of this often severe problem. Among these, several commonly used drug classes have been shown to increase the risk of aspiration pneumonia. These drugs should be withheld in the high-risk population whenever possible, alongside general measures, such as the semirecumbent position during sleep and feeding.