EDITOR: A fit 46-year-old female patient with diverticulitis refractory to conservative measures was scheduled for sigmoid colectomy. An epidural catheter was sited at the L3-4 interspace and a test dose of 4 mL bupivacaine 0.5 per cent injected from a labelled 20 mL syringe containing a total of 9 mL of solution. General anaesthesia was then induced with a standard rapid sequence induction. At the start of surgery, a further bolus dose of 'bupivacaine' was administered through the epidural catheter. Immediately following the injection, the anaesthetist noted that instead of giving bupivacaine, the remaining 6 mL of thiopentone 2.5 per cent left from the induction had been inadvertently administered. The catheter was immediately aspirated, removing 1 mL of fluid and the bacterial filter was discarded. Eighty millilitres of 0.9 per cent saline drawn up through a filter needle was injected over 30 min in an attempt to dilute the solution in the epidural space. The patient remained cardiovascularly stable and surgery was continued. In recovery, the patient had no complaints and was neurologically intact. Following the incident, the epidural catheter was left in place but no further doses of local anaesthetic or analgesics were administered. The catheter was removed the following morning. In this case, a relatively small dose of 2.5 per cent thiopental had been injected through an epidural catheter while the patient was under a general anaesthetic. In awake patients, the inadvertent administration of thiopental via the epidural route has been associated with pain and other transient neurological signs [1,2] as well as signs of systemic effects [3], but permanent damage has not been described using the 2.5 per cent concentration. The high lipid solubility of thiopental and the ample vascular supply of the epidural space may favour systemic absorption, leading to rapid decline of tissue concentration in the epidural space. Provided the epidural needle or catheter has not breached the dura mater, there seems to be effective separation of the subarachnoid compartment from the epidural space [4]. This is evidenced by a number of reports of other drugs that have been administered inadvertently via the epidural route. The majority of these resulted in no or only transient neurological impairment. These include drugs such as ephedrine [2], magnesium sulphate [5], methohexital [6], ether [7], and potassium chloride [8,9]. However, despite the apparently good dural protection, serious morbidity has also been reported following epidural administration of concentrated potassium chloride solution [10] and paraldehyde [11]. Various strategies have been adopted regarding the management of accidental administration of epidural thiopental. These include injection of local anaesthetic agents in the awake patient [1], epidural epinephrine [3], steroids [3] and epidural lavage through infusion of comparatively large volumes of normal saline [1]. Common to all management strategies are attempts to dilute the drug concentration in the epidural space, to diminish absorption across the dura by influencing the pH and to control the presumed inflammatory response to the drug. However, all these efforts are entirely empirical and have not been evaluated critically under controlled conditions. In particular, the role of steroids to prevent an inflammatory reaction is controversial. Epidural steroids may carry their own risks and their role has not yet been clarified. At present, epidural corticosteroids following inadvertent injection of other inappropriate drugs cannot be universally recommended. A. WEIGERT 62 Starfield Road, London, UK G. LAWTON Department of Anaesthesia, Lewisham University Hospital, Lewisham High Street, London, UK