Shock is a medical emergency associated with a high mortality. The underlying causes of shock such as haemorrhage, sepsis or myocardial insufficient should be corrected. The profound hypotension of shock must be treated promptly to prevent tissue hypoxia and organ failure. Volume replacement is essential to correct the hypovolaemia associated with haemorrhage and sepsis but may be detrimental in cardiogenic shock. Successful correction of hypovolaemia may alleviate hypotension in some cases. However, blood pressure in shock can be extremely low (sometimes a systolic pressure of less than 70 mmHg) and such profound hypotension (despite fluid replacement) and/or the presence of a law cardiac out put will often necessitate additional measures. Sympathomimetic agents are usually employed. They act as presser agents by producing vasoconstriction and also possess positive inotropic activity thus increasing cardiac out put. If hypotension is profound (for example systolic pressure less than 70 mmHg) noradrenaline is usually used; adrenaline or dopamine (not available at health center level) may be alternatives. If moderate hypotension exists (systolic pressure of about 70 to 100 mmHg) with hypoperfusion, dopamine is usually preferred.

The use of sympathomimetic inotropes and vasoconstrictors should therefore preferably be confined to the intensive care setting and under taken with invasive haemodynamic monitoring.

Adrenaline (Epinephrine)

Injection, 0.1 % in 1 ml ampoule

Indications: correction of hypotension, unresponsive to adequate fluid volume replacement, as part of shock syndrome caused by myocardial infarction, trauma, bacteremia, open-heart surgery, renal failure, chronic cardiac decompensation, drug overdose, or other major systemic illness; also severe anaphylactic shock, severe angioedema, cardiac arrest.

Cautions: -hyperthyroidism, hypertension, diabetes mellitus, ischaemic heart disease, arrhythmias, cerebrovascular disease, and elderly.

Drug interactions: - amitriptyline, clomipramine, atenolol, ether (Anesthetic), halothane, propranolol, timolol.

Contraindications: -asymmetric septal hypertrophy, pheochromacytoma, tachyarrhytmias.

Side effects: - tachycardia and arrhythmia, hypertension, tremor, anxiety, sweating, nausea, vomiting, weakness, dizziness, pulmonary oedema, headache.

Dose and Administration

Note: Different dilutions of epinephrine injection are used for different routes of administration.

Intramuscular or Subcutaneous injection, use 1:1000 epinephrine injection.

Slow intravenous injection; use 1:10000 epinephrine injection.

This route should be reserved for severely ill patient when there is doubt about the adequacy of circulation and absorption from the intramuscular site.

Storage: - at room temperature. Protect from light and freezing.