Septic Shock

The septic shock is an acute circulatory failure, involving disorders hemodynamic, metabolic and visceral, started by an infectious agent.

It is a cardiovascular cause of collapse.

It is defined by the appearance or the persistence of a Hypotension (NOT <90 or WFP <65 mm Hg) or frank signs of peripheral hypoperfusion (Lactatémie ≥ 4 mmoles/L, oliguria) in spite of an adequate vascular filling, during a serious Sepsis, or from the start at a patient having signs of Infection.

The septic shock is a medical emergency which requires care aiming at quickly raising the systemic blood pressure (by increasing blood volume and by managing Vasopresseur S such as the Catécholamine S) as well as Antibiotiques by intravenous way.

The septic shock remains pathological serious and remains associated with a strong death rate.

Epidemiology

The septic shock is one of the first causes of mortality in reanimation (50% of mortality)

Physiopathology

The normal response of our organization to an infection is done by the means of a cascade of immunological answers and humorales. Any excessive, prolonged, or unbalanced stimulation immune system will be able to give place to an “abnormal” answer of the organization.

The septic state of shock associates cardiac and vascular anomalies having for principal consequence an abnormal redistribution of blood in the microcirculation from where its name of shock " distributif" . These disorders testify to a systemic inflammatory answer resulting from the action of microbial substances.

The presence of a active Toxine of the bacterial agent in question will involve the activation of various processes:

secretion by the Macrophage S of TNF-alpha, Interleukine S (1 and 6),
secretion by the cells endothéliales of Prostaglandin S, NO₂
the activation of the complement, the system Kinine, the coagulation and the Fibrinolyse.

These reactions will have for consequences a tissue Hypoxie by:

myocardic toxicity , person in charge of the heart failure,
of the modifications of the capillary permeability , a vasodilatation as well as a procoagulante activity, persons in charge of the Hypovolémie and a interstitial edema .

All these elements can lead to a multi-visceral failure and the death.

Diagnosis

Two types of septic shocks are described:

a shock " chaud" with:

Hypotension, Tachycardia, Oliguria,
ends hot, red, dilated veins,
a Agitation, disorders of vigilance,
a Polypnée,
of the Fever or Hypothermia, shivers
a hemorrhagic syndrome.

a “cold” shock where marblings are found, and the ends are cold.

A " carry entrée" (origin of the infection) must be systematically required. It can be urinary (operation endovésicale, Pyélonéphrite), digestive (Angiocholite, Péritonite), respiratory, genital, cutaneous, venous (thrombophlébite suppurée on Cathéter), neuro-méningée, Endocardite.

Responsible germs

It is mainly about Bactérie S, but it can also be a Levure (Candida) or a Virus.

Negative Gram bacilli

The bacillus S negative Gram are most frequently responsible for septic shocks. Among them, one frequently finds the Escherichia coli, Pseudomonas, Proteus, Serratia, Bacteroïdes fragilis, méningocoque…
La Toxine is a Endotoxine (Lipopolysaccharide).

Cocci Gram positive

The Cocci positive Gram most frequently found are: the Pneumococcus, Streptocoque, Staphilococcus…
La Toxine corresponds in this case to a Exotoxin and a Antigène of wall.

Assumption of responsibility

Symptomatic treatment

It is first of all necessary to support transport in Oxygène (ventilation (oxygen with the mask, even Intubation trachéale so necessary), to maintain a rate of Hémoglobine higher than 10 g/dl), to correct the metabolic disorders (correction of a Acidose (to maintain a pH higher than 7,20), correction of a Hyperglycémie).

One will also have recourse to the vascular Remplissage, like with the use of Catécholamine S (Dobutamine, Dopamine, Noradrénaline…).

Treatment etiologic

It is about the treatment of the responsible Infection by:

the started Antibiotic use of S probabilists initially, selected according to the infectious hearth suspecté, of the ground, possible risk factors of resistance to antibiotics, after the bacteriological taking away,
then by a antibiothérapie adapted to the bacteriological results (Antibiogramme) of the various taking away carried out,
possibly, urgent surgical treatment if this one is necessary even essential to the eradication of the infectious hearth.

Prognostic elements

The four following factors are good prognostic elements:

the number of failures multivisérales at the time of the diagnosis,
the time of startup of the treatment,
the answer to the treatment,
the accessibility of the initial infectious hearth to the treatment.

The appearance of a heart failure, of turbid of the conscience, convulsives crises, a Leucopenia, metabolic disorders (Hyperlactatémie ou/et Hypoglycemia) is as for them very pejorative.

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