out.

vomiting is often preceded by nausea - the unpleasant, painless sensation
epigastric, often accompanied by vegetative-vascular reactions
: blanching of the skin, general weakness, dizziness,
hypersalivation, tachypnea, arterial hypotension, palpitations.
Nausea is often accompanied by denial of food intake (anorexia). In emetic
act involved the same muscles as in the act of swallowing, but it
peristalsis oppositely directed. Features of the mechanism are vomiting,
in particular, to reduce stomach with a closed gatekeeper anastaltic
movement of the esophagus with the opening of the cardia, in addition, play an important role to reduce
diaphragm and the muscles of the anterior abdominal wall.

vomiting must be distinguished from regurgitation and regurgitant .
Regurgitation may be preceded by vomiting, may be associated with physical activity and rhythm
breathing. Regurgitation, usually does not lead to bowel movement through the mouth.
Regurgitation - return of swallowed food into the mouth, with no characteristic odor
vomiting.

regulation of the vomiting reflex is carried out with the participation of diverse
neuroreflex links. The main afferent reflex arc by
are sensitive fibers of the vagus nerve. Vomiting center, located in
medulla oblongata near the sensitive nucleus of the vagus nerve, part of the reticular formation
and coordinated by the influences coming from the bark of
big brain, the vestibular labyrinth and the cerebellum. By efferent emetic reflex are
phrenic and vagus nerves are involved the following neurotransmitters: dopamine, histamine, acetylcholine, opiates, serotonin, g-aminobutyric acid
, substance P.

gag center is not directly responsible for humoral stimulation. Borison
and Wang found a second region, which participates in the act of vomiting - hemoretseptornuyu
trigger zone. Located at the bottom of the fourth ventricle of the brain,
outside the blood-brain barrier, it activated the humoral
impacts, but does not respond to electrical stimulation. Excitation
chemoreceptor trigger zone is not capable of causing a gag reflex
independently, but only by stimulating the vomiting center.

Aggravating effects, leading to the occurrence of vomiting, and options for implementation
vomiting reflex varied. In accordance with this release
following basic mechanisms of emesis: nervous reflex,
central, conditioned reflex and vomiting during pregnancy.

most often nausea and vomiting developed for neuro-reflex path and
are the result of excitation of the center of vomiting under the influence of the pulse,
entering the sensitive fibers of the vagus nerve in the esophagus, stomach,
intestine, biliary and urinary tract, uteass, peritoneum in response to stretching
walls of these organs or the effect of certain substances (eg, copper sulfate,
serotonin, prostaglandins, free radicals). Receptors of the vagus nerve in
mucosa of the upper gastrointestinal tract (pharynx, lower esophageal segment
, privratnikovoy the stomach, 12 duodenal and initial
departments jejunum) are characterized by the lowest threshold of stimulation. In this regard,
, violations of motor function of the esophagus, stomach, and the initial divisions
small intestine, accompanied by violation of the evacuation of food,
sposobstvovuyut nausea and vomiting.

Vomiting central origin may develop at
toxic effects on the vomiting center (carbon monoxide poisoning, dasgs
digitalis, apomorphine , chemotherapy, alkalosis, infections), with its
mechanical stimulation (concussion, hemorrhage, inflammation of brain membranes
, increased intracranial pressure), ischemia (poor circulation in the vertebrobasilar basin
). Vomiting accompanied by increased intracranial pressure
characterized by headache, photophobia, and absence of nausea.
nausea ismoreclosely related to the violation of peristalsis of the stomach and intestines
. Vomiting of central origin can be attributed, and if it
arise under the influence of abnormal impulses coming from the organ of hearing and
equilibrium (in the defeat of the labyrinth of the inner ear, motion sickness -
kinetoze or when the stimulus intensity).

to many peripheral areas, of which the center of vomiting can
receive afferent signals, is the heart. In patients with severe heart failure
, with attacks of cardiac asthma may also experience vomiting,
apparently mixed (central and reflex) origin.

familiar conditioned reflex vomiting, which has, in fact, cortical
origin, is increasingly concentrated among women and children. In this situation
signals coming from the higher nerve centers in response to an unpleasant smell, taste,
visual and verbal images, emotional distress, stressful situations.
Not having basically any anatomical changes
digestive or nervous system, the conditioned reflex vomiting can reach a degree
indomitable.

vomiting during pregnancy develops under the influence of endocrine changes, not
excludes impulses coming from the hypothalamus, pituitary and
pregnant uteass.

In his practice gastoenterologu most often meet with
gastro-intestinal tract, accompanied by nausea and vomiting
neuro-reflex origin. For this category include a wide range of
organic lesions, in particular, acute and chronic gastritis, peptic
disease and its complications (pyloric stenosis), esophagitis, acute INFECTIONS,
chronic intestinal obstasction, gallstone disease (hepatic colic ),
chronic pancreatitis, and malignant lesions of the stomach and pancreas,
postoperative syndromes in violation of gastrointestinal motility.
Cause neuro-reflex nausea and vomiting can be stimulated pathways
vagus nerve in stomatitis and pharyngitis, cough, sputum impact.

When acute gastritis the patient concerned a feeling of heaviness,
fullness in the epigastric region, nausea and vomiting. These symptoms occur against a background
observed gastric motility disorders: pyloric spasm and hypotension body.

When chronic gastritis type B and peptic ulcer
pathogenic role in the development of pain and vomiting is
acid-peptic factor. Vomiting usually occurs at an altitude of pain and
relief. The mechanism of vomiting helps to remove the annoying factor
- gastric juice, and vomiting is in the nature irritable.

When pyloric stenosis and eosinophilic gastritis with the defeat
output of the stomach is rare vomiting (1 per day - a few days,
depending on the severity of stenosis). In these circumstances, it is due
mechanical stretching the stomach wall and has the character emptied.

When acute poisoning or viral gastroenteritis
the predominant mechanism for the development of nausea and vomiting are
dysmotility of the stomach and the initial parts of the thin intestine, as well as hyper as a result of
effects of microbial toxins.

Chronic intestinal obstasction may be caused by
presence of pathological changes leading to a narrowing of the lumen of the intestine (obstasction),
and the disorder of blood supply, innervation and secondary, functional,
violation gastric motility (gastroparesis) and intestine (intestinal
psevdoobstasktsiya). Intestinal psevdoobstasktsiya most difficult for
systemic sclerosis, diabetes, hypothyroidism, hereditary
polyneuropathies (eg, family amyloid polyneuropathy), etc. For
ileus is characterized by persistent vomiting food during the deepening degree
obstasction may occur copremesis.

Various long-term complications of surgery on the stomach and biliary tract
, united under a common name
postgastrektomichesky syndrome and postcholecystectomical syndrome ,
may also be accompanied by nausea and vomiting. One of the most frequently encountered complications
this kind is the dumping syndrome developing after stomach resection
or non-selective vagotomy. Its manifestations are due to
excessively rapid evacuation of the contents of the stomach and high osmotic
load on the upper sections of the small intestine. Nausea and general discomfort
combined with signs of activation of the parasympathetic nervous system. Stenosis
abductor loops, gastritis, gastric stump is also possible the emergence of such
symptoms such as nausea and vomiting.

When biliary colic, and exacerbation of chronic pancreatitis vomiting
also has the nature of the neuro-reflex. It develops in response to biliary and pancreatic
hypertension, as well as related phenomena duodenostasis.

It must be remembered that the vomiting reflex is observed in diseases
distal intestines and other abdominal organs:
lesions of the peritoneum, the capsule of the liver, appendicitis, worm infestations, kidney, uterine ,
tubo-ovarian colic.

should mention such symptoms as vomiting, reflux ,
which occurs in patients with diseases of the pharynx and esophagus.
Most often it occurs when tumors or critical strictures of the esophagus, achalasia cardia
, esophagism, candidiasis, herpes or cytomegaloviass
pharyngitis and esophagitis. Esophageal vomiting develops due to violations
passage of food into the stomach and comes shortly after the meal (after a few minutes
after ingestion), especially after the intake of fluid. Characterized by the presence
undigested food and, often, a large amount of mucus. Esophageal vomiting not
is tase vomiting, but a regurgitation. Its implementation is not involved
complex reflex mechanism involving the vomiting center in the medulla
brain.

In recent years, considerable interest syndrome, nonulcer dyspepsia
, which is currently categorized
functional disorders. Allocate 3 clinical variants of non-ulcer dyspepsia:
yazvennopodobny, diskineticheskih and mixed (nonspecific). The symptoms of this disease
previously interpreted as a manifestation of chronic gastritis in
ideas about gipoatsidnom giperatsidnyh and gastritis.

For yazvennopodobnogo version of non-ulcer dyspepsia is characterized by hunger pains in the epigastric
, stoped taking antacids. For diskineticheskih - appearance
feeling of fullness in the epigastric region after eating, and nausea. As with
yazvennopodobnom and when diskineticheskih and mixed versions in the patient may experience vomiting
. Leading position in the pathogenesis of nonulcer dyspepsia
play dysmotility upper gastrointestinal tract: when
yazvennopodobnom variant observed increased incidence of duodeno-gastric reflux
at diskineticheskih option - reducing tension and easing
evacuation activity of the stomach . Assumed the role of psychosomatic
mechanism of development of these disorders. A necessary condition for diagnosis
functional (nonulcer) dyspepsia is an exception of organic pathology
gastrointestinal tract.

doctor in any specialty faced with nausea and vomiting,
acting as a manifestation of dasg side effects .
Mechanisms of development of such adverse effects are different for different
dasgs. Use of certain medications can be accompanied by
gastroparesis (chlorpromazine, tricyclic antidepressants, opioids,
anticholinergic agents) or to provoke stimulation of the receptors
mucosa of the gastrointestinal tract (corticosteroids, nonsteroidal anti-inflammatory dasgs
, colchicine, cytostatics , antibiotics, minerals,
iron supplementation, an overdose of magnesium-containing antacids, laxatives). At this
nausea and vomiting are in the nature of neuro-reflex.
Overdose of magnesium-containing antacids and laxatives, moreover, is accompanied by
general weakness, diarrhea, signs of electrolyte imbalance.

The question of whether the cause of the patient's nausea and vomiting
toxic effects of dasgs, in most cases
difficult. To establish a causal relationship at low and moderate symptoms
doctor can temporarily stop taking the dasg, and
then resume its use.

Nausea and vomiting may accompany the pathological conditions under which
observed violation of biochemical homeostasis in the body: uremia,
hypercalcaemia (on the background of renal insufficiency, metastatic
bones, dehydration ), hypokalemia, acute hyperglycemia, etc. These symptoms are often caused by
neuro-reflex and central effects of microbial
toxins and inflammatory mediators at the local and generalized infection.

Vomiting - one of the radical ways to remove harmful substances from the body and
is appropriate, if caused by the use or ingestion
irritating or toxic agent.

Repeated or anacatharsis leads to serious metabolic disorders
: dehydration and loss of electrolytes (potassium, sodium, chloride
and hydrogen ions), the development chloropenia, alkalosis, and coma.

need to monitor the condition of the patient to detect signs of dehydration
(dry, inelastic skin, impaired urination,
headache). It is advisable to use mineral water. In the presence of a patient
stomatitis or esophagitis should avoid drinking acidic beverages.

Careful observation of the general state of need in the event of vomiting in
patients with diabetes, especially among children. Repeated vomiting can lead to
development of ketoacidosis and dehydration in the next few hours or days.

Eliminating symptoms such as nausea and vomiting, and significantly impair quality of life
patient requires a differentiated approach. The mainstay of treatment
should be clarification and, if possible, eliminate the causes of
dyspeptic disorders or factors that provoke the gag reflex (eg,
treatment of gastritis, peptic ulcer, relief of cough). When dumping syndrome
for relief of symptoms is recommended shestirazovoe meals in small portions,
reduction of carbohydrate in the diet.

We often limited to symptomatic therapy. When
transient nausea and vomiting of symptomatic therapy involves fasting and
stop taking medications within 24 hours or longer (depending on
symptoms). Necessary for patient medication should
exist a suitable system of application, not amplifying nausea and vomiting.
Care should be relaxed surroundings and reduce the impact of those
factors that may provoke unpleasant symptoms. In
further recommended the appointment of sparing diet, nutrition shestirazovoe
small portions. If a serious condition and the symptoms persist it is recommended
installation nasogastric tube to decompress.

To prevent dehydration is usually enough to use
significant amount of liquid inside. If you continue, vomiting and increase
signs of dehydration there is a need for intravenous
plasma-saline solution.

for cancer patients to reduce the severity of nausea and vomiting
is very important oral hygiene, treatment of thassh.

There are a number of medicinal n?? Eparatov to relieve the symptoms of nausea and vomiting
.

Benzadiazepiny (diazepam, lorazepam) , having anxiolytic,
sedative effect, the ability to suppress parasympathetic (including,
vestibular) paroxysms of the most widely used in the treatment
conditioned reflex vomiting, and includes a regimen of vomiting, developing
against chemo-and radiotherapy of malignant tumors.

phenothiazines . This class of dasgs block dopamine receptors
(D ₂ ) in the central nervous system and, in particular in the mesolimbic system
trigger zone and vomiting center. This explains the existence of properties
neuroleptics and antiemetic properties. Phenothiazines prescribed in situations where there is a pronounced
, nekupiasemaya other means of vomiting: vomiting in
chemotherapy, radiation therapy for malignant novobrazovany, vomiting
central origin (trifluoperazine). Among the dasgs in this group
allocated haloperidol , which has a pronounced antiemetic
action. It lowers the tone of hollow organs, motility and secretion in
gastro-intestinal tract. Its use is limited, mainly conducting
patients in the postoperative period, the appointment in cases where there is a hiccup, vomiting,
resistant to treatment by other means.

M-cholinergic receptor blockers . Hyoscyamine butylbromide has
relaxing effect on smooth muscle cells of the gastrointestinal tract (mainly
antasm of the stomach, 12 duodenal ulcer), bile and urinary tract,
uteass, inhibits gastrointestinal motility and antistalsis and reduces
secretion. In addition, providing a central holinoliticheskoe effect. Prifiniya
bromide has a predominantly peripheral cholinolytic effect.
Dismengidrinat characterized by a mixed mechanism of action, blocking
central and peripheral M-cholinergic receptors and histamine receptor type 1 (H ₁ ).
spectasm of indications for their use is quite broad and includes nausea and vomiting during acute gastroenteritis
and fevers, vomiting, central and
conditioned reflex origin, vomiting, intolerance to medications
funds after radiotherapy. Appointment dismengidronata shown in
kinetozah.

antiemetic effects have selective antagonists
central and peripheral 5-gidroksitriptaminovyh (serotonin) receptor -
ondansetron, granisetron, tropisetron. The mechanism of action antiemeticheskogo
due to competitive inhibition of the chemoreceptor trigger zone of the cerebral
marrow and peripheral serotonin (5-HT ₃ ) receptors. Preparations
most well established in the prevention and relief of vomiting in the postoperative period
, particularly after cholecystectomy. Ondansetron,
tropisetron and granisetron are effectively used for the prevention and relief of nausea and vomiting
developing on the background of chemotherapy (eg, the introduction of high-dose cisplatin
) and radiation therapy for malignant neoplasms.

blockers H ₁ -histamine receptor . Meklozin -
antihistamine with weak anticholinergic activity.
interaction with receptors of the vestibular apparatus, thereby
shown antiemetic effect, decreasing dizziness. The main indication for
meklozina serve as motion sickness, disease
inner ear, Meniere's disease. Promethazine - a dasg with similar mechanism of action
. Has antiemetic, sedative, anxiolytic effects and
may be appointed for nausea and vomiting of various origins, being
phenothiazine derivatives, is also weak antipsychotic effect.

Application corticosteroids (dexamethasone, methylprednisolone)
helps to reduce severity of pain, nausea and vomiting in patients in the postoperative period
. In addition, corticosteroids help reduce
intracranial pressure.

prokinetic . Blocker of the peripheral and central dopamine receptors
metoclopramide (Reglan) is a highly
antiemetic. The dasg reduces the motor activity of the initial
segment of small intestine and helps to eliminate the duodeno-gastric reflux,
improves the evacuation of food from the stomach by increasing the activity of phase
antasm.

Metoclopramide is used for nausea and vomiting of various origins and
used for rapid elimination of symptoms and prevention. In
particular, the dasg has been used successfully in such conditions with
tasdnokupiasemoy nausea and vomiting, migraine, uremia, head injuries,
Beam hangover treatment with cytostatics, diabetic gastroparesis.

metoclopramide (Reglan) eliminates vomiting caused by overdose
dasgs, particularly morphine and apomorphine. In the postoperative period
reduces the severity of nausea and vomiting, which develop due to trauma
peritoneum.

Domperidone the most effective for nausea and vomiting that accompany
functional disorders of gastric motility and the initial divisions of the small intestine.

preparations of different groups . Antiemetic effect Hydroxyzine
associated with inhibition of activity of the subcortical stasctures of the central nervous system
. The dasg does not suppress the activity of the cerebral cortex.
Antiemeticheskim action has sulpiride and dimetpramid affecting
chemoreceptors trigger zone and reticular formation in the brain.

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Published with permission from Russian
Medical Journal.