1.
North American Summit on Aspiration in the Critically Ill Patient: consensus statement.
McClave, SA, DeMeo, MT, DeLegge, MH, DiSario, JA, Heyland, DK, Maloney, JP, Metheny, NA, Moore, FA, Scolapio, JS, Spain, DA, et al
JPEN. Journal of parenteral and enteral nutrition. 2002;(6 Suppl):S80-5
Abstract
Aspiration is the leading cause of pneumonia in the intensive care unit and the most serious complication of enteral tube feeding (ETF). Although aspiration is common, the clinical consequences are variable because of differences in nature of the aspirated material and individual host responses. A number of defense mechanisms normally present in the upper aerodigestive system that protect against aspiration become compromised by clinical events that occur frequently in the critical care setting, subjecting the patient to increased risk. The true incidence of aspiration has been difficult to determine in the past because of vague definitions, poor assessment monitors, and varying levels of clinical recognition. Standardization of terminology is an important step in helping to define the problem, design appropriate research studies, and develop strategies to reduce risk. Traditional clinical monitors of glucose oxidase strips and blue food coloring (BFC) should no longer be used. A modified approach to use of gastric residual volumes and identification of clinical factors that predispose to aspiration allow for risk stratification and an algorhythm approach to the management of the critically ill patient on ETF. Although the patient with confirmed aspiration should be monitored for clinical consequences and receive supportive pulmonary care, ETF may be continued when accompanied by appropriate steps to reduce risk of further aspiration. Management strategies for treating aspiration pneumonia are based on degree of diagnostic certainty, time of onset, and host factors.
2.
Aspiration-related illnesses: definitions and diagnosis.
Zaloga, GP
JPEN. Journal of parenteral and enteral nutrition. 2002;(6 Suppl):S2-7; discussion S7-8
Abstract
BACKGROUND Aspiration is a leading cause of morbidity and mortality. It is the most common cause of pneumonia and one of the most serious adverse effects of enteral nutrition support. It is important to use standardized terminology to define and discuss aspiration-related illnesses. METHODS Review of the medical literature and extraction of definitions and descriptions of aspiration-related illnesses. RESULTS Definitions, clinical features, diagnosis, and treatment of common aspiration-related illnesses are discussed. CONCLUSIONS Precisely defined terminology of aspiration-related illnesses adds consistency to this area of medicine and simplifies analysis and comparison of clinical studies.
3.
Detection of aspiration in enterally fed patients: a requiem for bedside monitors of aspiration.
Maloney, JP, Ryan, TA
JPEN. Journal of parenteral and enteral nutrition. 2002;(6 Suppl):S34-41; discussion S41-2
Abstract
BACKGROUND Pulmonary aspiration of gastric and oropharyngeal contents is common in enterally fed patients. Detection of early aspiration in these patients has relied on clinical impression, the coloring of enteral feedings with dyes, and less commonly the detection of elevated glucose in tracheal aspirates. The potential benefits, risks, and clinical use of bedside monitors of aspiration are under increasing scrutiny. METHODS Literature review. Although this review reflects the opinions of the authors, recommendations of an expert consensus panel (North American Summit on Aspiration, which included one author, J. P. Maloney) were also used to guide recommendations. The specific recommendations of that panel are presented elsewhere. RESULTS No large prospective clinical trials have been done to evaluate the use and safety of bedside monitors for aspiration. Clinical impression remains a poor "gold standard" of aspiration diagnosis in enterally fed patients. The coloring of enteral feedings with blue dyes (chiefly FD&C Blue No.1) is ubiquitous in hospitals despite evidence that it is not sensitive and potentially harmful. Cases of absorption of blue dye from enteral feedings in patients with critical illness have raised concern about the safety of the blue dye method, particularly in light of apparent toxic effects of these dyes on mitochondria. The glucose detection method has not been embraced; it too has little use and is labor intensive. CONCLUSIONS Use of colored dyes in enteral feedings and glucose detection methods should be abandoned. Nonrecumbent positioning is an evidenced-based method for aspiration prevention that needs to be re-emphasized. Novel bedside methods of detecting early aspiration are needed to supplement preventative strategies.
4.
Risk factors for aspiration.
Metheny, NA
JPEN. Journal of parenteral and enteral nutrition. 2002;(6 Suppl):S26-31; discussion S32-3
Abstract
BACKGROUND There are numerous risk factors for aspiration in tube-fed critically ill patients. However, there is confusion about the extent to which these factors actually contribute to aspiration. The purpose of this literature review was to summarize findings from selected research studies. METHODS A nonexhaustive literature search was conducted to identify risk factors for aspiration in tube-fed, critically ill patients. The most commonly cited factors were decreased level of consciousness, supine position, presence of a nasogastric tube, tracheal intubation and mechanical ventilation, bolus or intermittent feeding delivery methods, high-risk disease and injury conditions, and advanced age. RESULTS Many studies of aspiration risk factors have relatively small sample sizes and used equivocal definitions of aspiration. Although some addressed aspiration as an outcome, others considered gastroesophageal reflux or pneumonia as outcomes. Despite these variations, authors almost uniformly agree that a decreased level of consciousness and a sustained supine position are major risk factors for aspiration. There is less agreement regarding the effect of a nasogastric tube (or its size) on aspiration and on the effect of various formula delivery methods. CONCLUSIONS A decreased level of consciousness is a major risk factor for aspiration, as is a sustained supine position. Although some authors favor using small-bore feeding tubes to prevent aspiration, there seems to be insufficient data to warrant this action. Although strong data are lacking regarding feeding delivery methods, there are more data to support continuous feedings than bolus/intermittent feedings in high-risk patients.