Acute aspiration

Acute aspiration is the inhalation of foreign material into the airways beyond the vocal cords with variable manifestations that result in aspiration bronchiolitis, aspiration pneumonitis, aspiration pneumonia, and acute respiratory distress syndrome (ARDS).

Usually occurs in patients with altered level of consciousness, dysphagia, or impaired cough reflex.

Screening for dysphagia is recommended for patients at risk of, or following, aspiration (including all patients after an acute stroke).

Clinical presentation and severity depends on the volume and type of the aspirated material as well as the host defenses, such as adequate cough reflex, intact mucociliary barrier, and respiratory reserve.

Anesthesia-related aspiration of gastric contents can be prevented by identifying patients susceptible to vomiting and reflux, minimizing gastric contents before surgery, avoiding drugs that reduce gastric emptying, minimizing emetic stimuli, and avoiding complete loss of protective reflexes from oversedation.

Antibiotics are not indicated early after aspiration of gastric contents but they should be considered if the pneumonitis does not resolve after 48 hours or if there is clear risk or susceptibility for infection.

Patients with neurologic deficits, infants, older patients (age >70 years), and debilitated patients with dysphagia may also aspirate barium sulfate during radiologic procedures, which can result in severe bronchiolitis and pneumonitis.

Aspiration is the inhalation of liquid or solid particles, particularly food or gastric contents, into the airways below the vocal cords.[1]Raghavendran K, Nemzek J, Napolitano LM, et al. Aspiration-induced lung injury. 2011 Apr;39(4):818-26. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3102154 http://www.ncbi.nlm.nih.gov/pubmed/21263315?tool=bestpractice.com It can result in aspiration pneumonitis (chemical injury) or aspiration pneumonia (infection), both of which can lead to acute respiratory distress syndrome (ARDS). See Aspiration pneumonia and Acute respiratory distress syndrome.[1]Raghavendran K, Nemzek J, Napolitano LM, et al. Aspiration-induced lung injury. 2011 Apr;39(4):818-26. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3102154 http://www.ncbi.nlm.nih.gov/pubmed/21263315?tool=bestpractice.com [2]Marik PE. Aspiration pneumonitis and aspiration pneumonia. N Engl J Med. 2001 Mar 1;344(9):665-71. http://www.ncbi.nlm.nih.gov/pubmed/11228282?tool=bestpractice.com If the central airways are completely occluded, asphyxiation may quickly ensue. See Foreign body aspiration. Awareness is increasing for silent or more subclinical chronic micro-aspiration, which has been implicated as a potential aggravating mechanism across a variety of disorders, such as interstitial lung disease, asthma, COPD, and chronic cough. Chronic micro-aspiration is not covered in this topic.[3]Lee AS, Lee JS, He Z, et al. Reflux-aspiration in chronic lung disease. Ann Am Thorac Soc. 2020 Feb;17(2):155-64. https://www.atsjournals.org/doi/10.1513/AnnalsATS.201906-427CME http://www.ncbi.nlm.nih.gov/pubmed/31697575?tool=bestpractice.com