Poisoning with barbiturates

Description:

From medicines, poisonings with barbiturates take the noticeable place on use frequency in household suicide attempts.

Depending on duration of action allocate barbiturates long (8 — 12 hours — phenobarbital), an average (6 — 8 hours — barbital (veronal), barbital-sodium (medinal), etc. also short action (4 — 6 hours — etaminal-sodium (nembutal). A lethal dose for these drugs concentration in blood more than 0,1 g/l is considered. Weight of a condition of the victim amplifies at associated diseases, especially a liver and kidneys.

Poisoning with barbiturates symptoms:

Allocate 4 main clinical syndromes:
1. Coma and other neurologic frustration.
2. Breath disturbances.
3. Dysfunctions of CCC.
4. Trophic frustration and renal failure.
Moderate and deep devocalization, sopor and moderate coma (synonym: a coma of I) have no specific characters.

For a deep coma (synonym: the coma of II) specific characters is the expressed hypersalivation, a bronchorrhea of various degree. Disturbance of breath due to retraction of language or aspiration of emetic masses is possible, but respiratory depression of the central genesis still is absent. Tachycardia is noted, but there is no expressed disturbance of a hemodynamics. On an ECG, in addition to compensatory sinus tachycardia, it is possible to find diffusion changes in a myocardium. Arterial hypotension, oliguria. On EEG specific "barbituric spindles" appear. In a blood plasma high concentration of barbiturates is noted.

For an ultraboundary coma (synonym: the coma of III) a distinguishing character is  disturbance of breath of the central genesis owing to oppression of a respiratory center and bystry development of violent dermatitis.

Poisoning with barbiturates reasons:

Barbiturates make selective toxic impact on TsNS which is shown oppression of function of a cerebral cortex owing to impact on metabolism of nervous cells through decrease in consumption by them of oxygen and disturbance in tsitokhromny system that, in turn, leads to disorder of formation of acetylcholine and, therefore, disturbance of transfer of nervous impulses in TsNS.

Toxic impact on a trunk part and myelencephalon leads to a loss of consciousness and approach of coma, to dysfunction of breath of the central genesis that is shown by reduction TO and FASHION; to paralysis of a vasomotor center which harbinger is the kollaptoidny state; to disappearance of pain, tactile and tendon jerks; to disbolism, increase in a thermolysis, fall of temperature of a body; to oppression of a diuresis, and the oligouriya promotes increase in level of residual nitrogen in blood; to a vagotonia that is shown by strengthening of secretion in bronchial tubes.

Cardiovascular system. Toxic doses of barbiturates reduce sokratitelny ability of a myocardium and a tone of smooth muscles of vessels that, in turn, promotes reduction of UO, MOS, TsVD, falling of PSS, the ABP. Barbiturates in high concentration make immediate effect on a capillary bed — its permeability increases that is fraught with emergence of complications in the form of fluid lungs and a brain. In the subsequent this pathological cascade causes bystry emergence of trophic frustration in the form of the violent dermatitis and a necrotic dermatomyositis proceeding as quickly developing decubituses.

Treatment of the Poisoning with barbiturates:

It is necessary to pay attention that at treatment of poisonings with barbiturates the former earlier traditional method of therapy turned out high doses of analeptics (Cordiaminum, caffeine, etc.) ineffective at a deep barbituric coma and even dangerous owing to possible development of convulsive states and respiratory complications therefore the specified drugs can be used only at patients with easy degree of poisoning.

In the pathogenetic way of treatment it is necessary to consider the accelerated release of an organism from barbiturates method of an artificial diuresis, and in the presence of signs of respiratory insufficiency — transfer of the patient into IVL. Wide use of this method at treatment of patients with poisonings with barbiturates of heavy degree made some kind of revolution in toxicology, comparable with an era of antibiotics in surgery. So, if mortality at patients with a heavy coma against the background of treatment with respiratory analeptics made 20 — 30%, then at treatment by method of an artificial diuresis in combination with IVL this figure decreased approximately by 10 times and makes 2 — 3% now.

The method of an artificial diuresis is carried out in combination with alkalization of plasma of 4% sodium bicarbonate solution for bystreyshy removal of barbiturates from blood. It is necessary to emphasize importance of completion of electrolytes of blood at this method of treatment and to point to contraindications (a persistent collapse, cardiac asthma, an acute renal failure, an Art. IIB — III circulatory unefficiency). Control of the carried-out therapy is exercised by definition of TsVD, a hematocrit, electrolytes of plasma, a diuresis and, of course, concentration of barbiturates in blood and urine. A transfer of the patient into IVL is made according to the standard indications.