You mean adrenaline, right? There are three methods of using epinephrine for rescue in cardiac arrest, namely intravenous bolus injection, intracardiac injection and intratracheal administration. Of course, the preferred and most convenient route of administration is intravenous injection, which is also the most commonly used route of administration in clinical practice. Intratracheal administration may also be considered when the patient has been intubated. As for intracardiac injection, it was once listed as the first choice, but it is difficult to operate and can easily cause heart rupture, cardiac tamponade and other complications, so it is basically no longer used.

Therefore, in summary, the current preferred route of administration of epinephrine is intravenous injection.

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