Zusammenfassung
Die einfache Verfügbarkeit von Antagonisten darf nicht zum sorglosen Umgang mit Agonisten
verleiten. Besonders für Opiat- und Benzodiazepinantagonisten muß wegen der unter
Umständen schwerwiegenden Nebenwirkungen eine saubere Indikation gestellt werden.
Für die Antagonisierung der neuromuskulären Blocker kann die Indikationsstellung großzügig
gefaßt werden. Die Dosis aller Antagonisten muß in Abhängigkeit von der beobachteten
Wirkung titriert werden. Die Antagonisierung ersetzt nicht die Überwachung des Patienten.
Im Rettungswesen ist die Gabe der Antagonisten nur ausnahmsweise sinnvoll. Hier hat
die Sicherstellung der Vitalfunktionen Priorität.
Summary
In modern anaesthesia various antagonists are used. They provide efficient tools to
facilitate better control of pharmacological effects and side effects of drugs routinely
used in anaesthesia. Naloxone is a competitive antagonist of opioids without any intrinsic
activity. It counteracts respiratory depression, pruritus, sedation and analgesia
caused by opioids. It is fast-acting with a duration of action of 45 to 90 min. Several
investigators have reported severe side effects of naloxone including hypertension,
tachyarrhythmias, left heart failure and cardiac arrest, and hence the use of naloxone
must be carefully considered in every single patient. Flumazenil is a competitive
antagonist of benzodiazepines. It is a remarkably safe drug and very effective to
terminate all benzodiazepine effects in anaesthesia and intensive-care patients. Serious
complications caused by flumazenil have been reported in patients receiving benzodiazepines
in the treatment of seizure disorders and in patients with mixed intoxications. Neostigmine
is one of several antagonists of neuromuscular blocking agents. Its side effects include
bradycardia, increased bronchial secretions and increased peristalsis. Indication
depends on the results of neuromuscular monitoring. Physostigmine is an unspecific
antagonist of the central anticholinergic syndrome, an acute psychosis that may be
caused by numerous drugs used in anaesthesia. Generally, antagonists should be carefully
titrated. In emergency medicine the use of these antagonists is not recommended; the
primary goal is to restore vital functions.
