What key clinical entities must be considered in the initial assessment of a hospitalized patient with acute nausea and vomiting?
What is the clinical diagnostic approach to the inpatient with nausea and vomiting?
How should patients with nausea and vomiting in the hospital setting be treated?
A 28-year-old woman was admitted from clinic with refractory nausea and vomiting. She has a history of long standing type 1 diabetes mellitus, which has been complicated by retinopathy and neuropathy. From a gastrointestinal standpoint, symptoms began 3 years ago with the onset of early satiety, nausea, and vomiting. This has progressively worsened despite decent glycemic control and aggressive lifestyle modification. She reports constant nausea, which is worse with food, but present to some extent even if she has had nothing to eat. She also reports vomiting after most meals—this can be as soon as minutes after eating or as long as hours. Symptoms are present with both liquids and solids and may even be worse with liquid intake. She is taking ondansetron every 8 hours and promethazine as needed in between ondansetron doses. She has attempted therapy with metoclopramide in the past but did not feel any improvement and also developed a tremor (which reversed upon stopping metoclopramide). She had an attempted solid gastric emptying study but vomited the eggs shortly after ingestion. Her liquid emptying study was markedly abnormal. Prior endoscopy showed no evidence of gastritis, peptic ulcer disease, or gastric outlet obstruction. An upper gastrointestinal (GI) series with small bowel follow-through showed delayed gastric emptying, no abnormal distention, and apparently normal small bowel transit. She has now lost 70 pounds over the past year and was admitted for evaluation, rehydration, and further management.
Nausea and vomiting are common and uncomfortable symptoms with a large number of underlying causes. Nausea is a subjective sensation, usually experienced in the epigastrium or throat when vomiting is imminent (although vomiting may or may not occur). Nausea may be followed by retching, which is repetitive active contraction of the abdominal musculature. Retching may occur in isolation without the forceful expulsion of gastric contents. In contrast, vomiting is a highly physical event that results in the evacuation of gastric contents. This should be distinguished from regurgitation, which is the effortless reflux of gastric or esophageal contents to the hypopharynx.
Studies have suggested that the act of vomiting is controlled by a central neurologic center. Borison and colleagues have studied the mechanism of vomiting in cats and found that vomiting can be induced by electrical stimulation of a “vomiting center” located in the dorsal portion of the medulla. These studies, however, have not yet been repeated in human subjects. Experimental studies have also suggested that a chemoreceptor trigger zone (CTZ) activates the vomiting center when stimulated.
Emetic stimuli can cause vomiting by one of two mechanisms. One ...