The nasogastric feeding tube as a risk factor for aspiration and aspiration pneumonia.

PURPOSE OF REVIEW: Aspiration is one of the most common complications in enterally fed patients. The source of aspiration is due to the accumulation of secretions in the pharynx of reflux gastric contents from the stomach into the pharynx. The true prevalence of aspiration is difficult to determine because of vague definitions, poor assessment methods, and varying levels of clinical recognition. RECENT FINDINGS: There is evidence in the literature showing that the presence of a nasogastric feeding tube is associated with colonization and aspiration of pharyngeal secretions and gastric contents leading to a high incidence of Gram-negative pneumonia in patients on enteral nutrition. However, other aspects may be equally important and should also be considered when evaluating a patient suspected of having aspiration and aspiration pneumonia. The mechanisms responsible for aspiration in patients bearing a nasogastric feeding tube are (1). loss of anatomical integrity of the upper and lower esophageal sphincters, (2). increase in the frequency of transient lower esophageal sphincter relaxations, and (3). desensitization of the pharyngoglottal adduction reflex. SUMMARY: Sometimes it is possible to differentiate whether the aspirate is gastric or pharyngeal. The kind of bacterial contamination is, however, more difficult to establish. Oral or dental disease, antibiotic therapy, systemic illness or malnutrition and reduction of salivary flow are responsible for colonization of Gram-negative bacteria in oral and pharyngeal flora in nasogastric-tube-fed patients. The use of a nasogastric feeding tube and the administration of food increase gastric pH and lead to colonization of gastric secretions. It has also been suggested that gastric bacteria could migrate upward along the tube and colonize the pharynx.

Diagnostic methods for the detection of anterograde aspiration in enterally fed patients.

PURPOSE OF REVIEW: The diagnosis of aspiration and its origin in patients on enteral tube feeding is challenging to the physician and provides an important means to prevent pneumonia. This review examines the most recent studies and developments in the field with an approach to the technical aspects of diagnostic methods. RECENT FINDINGS: The methods more commonly used to detect anterograde aspiration in clinical practice are fiberoptic endoscopic evaluation of swallowing and modified barium swallowing. Recent studies have shown that although these methods may provide the diagnosis of aspiration, their use for clinical monitoring is not appropriate. The studies comparing fiberoptic endoscopic evaluation of swallowing and modified barium swallowing have demonstrated that both tests present similar sensitivity, specificity and predictive values. SUMMARY: The different methods used to diagnose anterograde aspiration are appropriate for clinical practice, with a low complication rate and few contraindications. In most instances, the early diagnosis of aspiration and evaluation of other factors such as laryngeal sensibility, may predict the occurrence of aspiration pneumonia.

Hemorragia digestiva alta não varicosa: estudo prospectivo dos fatores prognósticos / Non-varicose upper gastrointestinal hemorrhage: prospective study of prognostic factors

A homorragia digestiva alta (HDA) é responsável por cerca de 350.000 das internações por ano (EUA), tendo grande morbimortalidade. Este trabalho tem como objetivo estudar, através de um estudo prospectivo, quais são os fatores clínicos endoscópicos prognósticos e quais são os resultados do tratamento clínico-endoscópico-cirurgico em pacientes portadores de HDA. Estudaram-se prospectivamente todos os pacientes portadores de HDA no Hospital nossa Senhora das Graças, no período de abril de 1997 a maio de 1998.Os pacientes eram submetidos à endoscopia digestiva alta, cujo laudo era anexado a um protocolo. Os dados assimobtidos foram agrupados em tabelas e usou-se a análise estatística simples e os testes de fisher, doqui-quadrado e t de student. foi estudado um total de 94 pacientes; destes 42,6por cento apresentaram hematêmese, 69,1por cento melena e 2,1 por cento enterorragia; 45 (47,9por cento) usaram medicamentos e 21 (22,3por cento) antiinflamatórionão esteroide.Mais da metade dos pacientes estudados (56,4por cento) apresentava alguma doença associada. A causa mais frequente de HDA foi a úlcera bulbar, com 26,2 por cento. Dos pacientes portadores de doença ulcerosa(48,6por cento), 16 (17,2por cento) foram classificados como Forrest IIA; 35 pacientes (37,8por cento) foram submetidos à terapeutica endoscópica com adrenalina 1:20.000 e, destes, somente dez ressangraram; três (13,2por cento) foram submetidos a tratamento cirúrgico e houve uma razão significante estatisticamente (p<0,01) para a ocorrência de indicação cirúrgica e uso de mais de três unidades de papa de hamácias,.Conclui-se com este trabalho que a HDV vem sendo diagnosticada e tratada mais precocemente com o uso de endoscopia, mas que sua mortalidade pouco foi modificada com a utilização de terapêutica endoscopica devido à associação de outros fatores clínicos. Por outro lado, om o uso da endoscopia terapeutica houve diminuição na indicação cirúrgica para o tratamento da HDA