RT Book, Section A1 Venkatasubramani, Narayanan A1 Li, B.U.K. A2 Bishop, Warren P. SR Print(0) ID 55942430 T1 Chapter 2. Vomiting T2 Pediatric Practice: Gastroenterology YR 2010 FD 2010 PB The McGraw-Hill Companies PP New York, NY SN 978-0-07-163379-6 LK accesspediatrics.mhmedical.com/content.aspx?aid=55942430 RD 2024/03/28 AB Vomiting is the forceful retrograde expulsion of gastric contents through the mouth consequent to the coordinated contraction of diaphragm, abdominal, and respiratory muscles. It is associated with a characteristic autonomic response, including pallor, lethargy, hypersalivation, and tachycardia. This differentiates vomiting from regurgitation, which is an effortless involuntary reflux of undigested gastric contents and is not associated with abdominal/diaphragmatic contractions or autonomic responses. Nausea is the subjective unpleasant sensation of impending vomiting that precedes but is not always associated with vomiting. Emesis is a term that can be used to describe any expulsion of gastric contents, and is useful to the physician when describing symptoms that have not yet been fit into the more exact categories of vomiting or regurgitation. Rumination is voluntary reflux of gastric contents within the first hour after eating and is associated with chewing and reswallowing of undigested food. Retching or “dry heaves” is the activated emetic reflux without vomiting, due to vomiting motion against a closed glottis (Table 2–1). Vomiting should also be differentiated from coughing or spitting of mucus from the lungs.