Anaphylactic Shock

Anaphylactic ShockCLINICAL SIGNS:

* very rapid onset of appearance: <2 min in 95% of cases, (max: 20 min).

* cutaneous signs:

– diffuse urticaria, pruritus of extremities , flushs, erythema, angioedema.

* cardiovascular signs:

– palpitations, malaise, anxiety, anxiety.

– collapse.

– state of shock :

 running pulse, mottling, cold extremities, hypotension <90 mmHg, pallor, sweating.

– angina, arrhythmia, infarction, PAO.

– cardiac arrest.

* respiratory signs:

– cough, laryngeal dyspnoea or polypnea.

– stridor, sibilance, cyanosis.

– respiratory arrest.

* digestive signs:

– epigastric pain.

– nausea, vomiting, diarrhea.

– pruritus of the palate, dysphagia, edema of the tongue, edema of the glottis .

DIFFERENTIAL DIAGNOSIS:

* vagal discomfort.

* cardiogenic or hypovolemic shock.

* anaphylactoid reaction.

* acute asthma.

ETIOLOGY:

* “Idiopathic”.

* Hymenoptera venom (18%): wasp, bee, hornet or snake venom.

* food intake: peanut, crustaceans, strawberries, egg, nuts, fish, …

* after a desensitization sting.

* taking aspirin or analgesics (15%), beta-lactams (9%).

* anesthetic agents (25%), filling solutes (2.5%).

* iodinated contrast product.

ADDITIONAL TESTS:

* scope, SpO².

* ECG: disorders of excitability, conduction, repolarization.

* blood gas.

TREATMENT:

* lengthen the patient, raised legs.

* venous route: filling with crystalloids (Ringer lactate, sodium chloride 0.9%).

* Oxygen therapy mask: 8-10 l / min.

* Adrenaline :

– 1 mg (0.25 mg in children) in 10 ml, inject 1 ml / min IV to obtain a blood pressure> 100 mmHg.

 Then possible relay with the electric syringe: 0.1-0.5 μg / kg / min (0.25-1 mg / h).

– if moderate form or if IV impossible: 0,5 mg in SC or IM to be repeated every 5-10 mn until a TA> 100 mmHg.

– we can also choose the tracheal route or make an injection under the tongue.

– double the doses at least if subject to beta-blocker.

* Solumedrol : 120 mg IV then hydrocortisone hemisuccinate: 200 mg / 4h. IV (1 mg / kg in children).

* if laryngeal dyspnea:

– Dyspne-Inhal: 5 to 15 sprays or aerosol of Adrenaline: 1 mg in 5 ml of isotonic salty.

– aerosols of beta-2-mimetics: 10 sprays in an inhalation chamber.

* possibly: Dobutrex, 1 to 10 μg / kg / min (2 to 25 μg / kg / min in children).

* if laryngeal spasm or vital distress:

– Oro or naso-tracheal intubation and assisted ventilation after possible sedation with Hypnovel and Fentanyl.

* hospitalization: keep at least 24 hours , even if the episode is stopped because of risk of recurrence.

* prescribe a box of Anahelp or Anakit especially if impossible eviction of the allergen (attention to abusive self – medications).