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Background and Aims The main goal of an epidural test dose (ETD) is to avoid the inadvertent injection of large doses of opioids and local anaesthetic either intravascularly, subduraly or intrathecally. Although some literature suggests that the ETD is not an effective method for identification of epidural catheter (EC) misplacement in obstetrics, it is still common practice in many maternities.

Methods We review 3 clinical scenarios of complications after the administration of epidural anaesthesia or analgesia, where the ETD failed to reveal the catheter misplacement.

Results The first case report refers to a pregnant woman who received a sequential block for labour analgesia. An ETD with lidocaine was administered after the technique. One hour later an epidural dose for analgesia was administered, which caused a complete motor block with hypotension and fetal distress. The second case describes an epidural technique for labour analgesia, followed by an uneventful ETD with lidocaine and epinephrine. Shortly after a ropivacaine bolus, the patient developed a patchy block and a Horner syndrome. The third case refers to a caesarean section with an EC already in place, tested with a lidocaine bolus. After the administration of ropivacaine for surgical anaesthesia, the patient developed severe respiratory distress with the need for mechanical ventilation.

Conclusions There are many cases in literature where the ETD was ineffective and even associated with adverse events. These three case reports show that the ETD does not prevent the occurrence of adverse outcomes. More studies are required to establish which strategy is valid for early detection of EC misplacement.