Respiratory depression following administration of low dose buprenorphine as postoperative analgesic after fentanyl balanced anaesthesia

Opioids are among the most ancient and widely used drugs in anaesthesiology. The pharmacology of opioid analgesics and their receptors is a complex and not fully understood matter; even more complex are the interactions between different classes of opioids at both molecular and clinical levels. We want to report here a clinical observation to emphasize the importance of the theoretical basis of anaesthesiology. This paper contains a clinical observation of respiratory depression following the administration of buprenorphine as postoperative analgesic after balanced anaesthesia with fentanyl. The observed case is interpreted in the light of the pharmacokinetics and pharmacodynamics of the different classes of opioid drugs (agonists, agonists–antagonists, antagonists) and of the interactions with their respective receptors.