Vomiting is a reflex act of evacuation of gastric contents through the mouth and nose.
Vomiting is a complex process of coordinated work of the abdominal muscles, stomach, esophagus, pharynx and tongue muscles. The vomiting center that controls the act of vomiting is located in the medulla oblongata.
Under various influences, an impulse arises in the vomiting center – an electrical signal that spreads to the stomach, esophagus and arbitrary muscles. When vomiting, the walls of the stomach relax, the lower esophageal sphincter – a muscular ring that blocks the return flow of food from the stomach to the esophagus – relaxes. Under the influence of the contraction of the diaphragm and the muscles of the abdominal wall, the pressure in the abdominal cavity increases, and there is a rapid ejection of the contents of the stomach through the mouth and nose. At the same time, the epiglottis and the root of the tongue block the airways so that asphyxia (choking with vomit) does not occur.
Vomiting is usually preceded by nausea, reflex swallowing movements, increased salivation, lacrimation, sometimes trembling, a feeling of cold hands and feet, sweating, a feeling of crawling all over the body.
Causes of vomiting
Allocate vomiting “gastric” and “brain”. brain vomiting develops with traumatic brain injuries, cerebral hemorrhage, brain tumors, compression of the brain substance, and so on. The main difference between such vomiting: there is no relief after. Vomiting of this nature can be observed at high temperature (especially in children), severe intoxication (with neuroinfections), and emotional stress. With cerebral vomiting, the vomiting center is irritated either mechanically or chemically (with toxins dissolved in the blood in various diseases).
Sometimes vomiting occurs during a severe bout of coughing, hiccups, and so on. This is due to the proximity of the nerve centers of these reflexes in the medulla oblongata: if one of them is excessively irritated, the excitation spreads to the neighboring ones, which can cause a gag reflex.
“Gastric” vomiting most often develops with poisoning, food infections, and other non-infectious diseases of the gastrointestinal tract (gastritis, peptic ulcer, pancreatitis, cholecystitis, etc.). Vomiting in this case, as a rule, is accompanied by temporary relief, a decrease in nausea and abdominal pain.
Read more: First Aid for Vomiting
Why is vomiting dangerous?
Vomiting is a protective reflex, due to which the body is cleansed of toxic substances that have got inside. When poor-quality food is ingested, toxins, absorbed into the blood, irritate the chemoreceptor zone in the brain, from where a signal for help is sent to the vomiting center, after which the stomach tries to get rid of harmful contents.
In addition, vomiting is often an important diagnostic feature in concussion and other severe conditions.
However, vomiting, in addition to discomfort, is fraught with other dangers:
With persistent, repeated (indomitable) vomiting there is a large loss of fluid, an electrolyte imbalance (the pH of the body environment shifts to the alkaline side, as a result of a large loss of hydrochloric acid of gastric juice). This happens especially fast in children. In the presence of varicose veins in the esophagus (for example, with cirrhosis of the liver), persistent vomiting can cause bleeding from the esophagus.
With habitual vomiting (repeating every day after eating) the body is left without food, which leads to rapid exhaustion.
In a state of disturbed consciousness (with alcohol intoxication, after anesthesia, etc.) the occurrence of vomiting is dangerous as asphyxia: the victim may choke on vomit.
Vomiting of scarlet blood or “coffee grounds” (when the vomit is black) indicates bleeding from various parts of the gastrointestinal tract, which requires immediate medical attention.
What to do with vomiting?
If vomiting occurs for no apparent reason, does not bring relief and is accompanied by a deterioration in the general condition, it is better not to hesitate and consult a doctor. Urgent medical attention requires vomiting after a blow to the head, against the background of high or low blood pressure, accompanied by impaired speech, facial asymmetry, weakening of the strength of the muscles of the arm or leg.
Special attention deserves persistent vomiting in young children. Babies quickly become dehydrated, especially if vomiting is accompanied by loose stools. In these cases, be sure to see a doctor as soon as possible.
If vomiting is caused by poor-quality food and is accompanied by other signs of poisoning, before the doctor arrives, you can take sorbents (activated charcoal, polysorb, enterosgel, smecta), try to drink more warm, slightly acidified liquid. You need to drink in small portions, but often. For soldering children, it is recommended to give them 1 teaspoon of liquid every 5 minutes.