1 Case report Uneventful recovery following accidental epidural injection of dobutamine Bastiaan M. Gerritse, M.D., Ph.D., Daan de Vos, R.N.A, Anton W. Visser, M.D., Ph.D. Department of Anesthesiology, Intensive Care and Pain Management, Amphia Hospital, Molengracht 21, 4818 CK Breda, The Netherlands Correspondence: Dr. B.M. Gerritse Department of Anesthesiology, Intensive Care and Pain Management, Amphia Hospital, Molengracht 21, 4818 CK Breda, The Netherlands Telephone: 076-5955000 Email: bgerritse@amphia.nl
2 Errors in drug administration are common in clinical anesthesia. We report an uneventful recovery after accidental thoracic epidural injection of dobutamine, which to our knowledge, has not been reported before. A 81-yr-old female (length 162 cm, weight 63 kg) was scheduled to undergo open partial gastrectomy due to the presence of a Gastrointestinal Stromal Tumor. Previous history consisted of a classic cholecystectomy, cataract surgeries and chronic atrial fibrillation. Home medication consisted of digoxine, nitrofurantoin, esomeprazol and ferrogluconate. An epidural catheter was placed uneventfully at the Th6-7 interspace. A test dose of 3 ml of lidocaine 2% was administered without any visible effect. Blood pressure was 150/75 mm Hg, with a heart rate of 80/min. Anesthesia was inducted with propofol, rocuronium and sufentanil through a periferal venous catheter, anesthesia was maintained by administration of sevoflurane. A 20G catheter was inserted in the right radial artery, a triple lumen catheter was inserted in the right internal jugular vein. After induction of general anesthesia and prior to incision by the surgeon, five ml of a solution which was thought to be bupivacaine given epidurally. Within minutes the injection was followed by a quick increase of heart rate and blood pressure to 125/min and 208/120 mm Hg respectively. Since these changes coincided with the surgical incision, insufficient epidural anesthesia was suspected and 25 μg of sufentanil i.v. was given. Blood pressure and heart rate slowly decreased to baseline values over the next 25 min. During this time, it was discovered that the injected solution had been drawn up from a multidose vial of dobutamine 5 mg/ml (Hameln Pharma Plus GmbH, Hameln, Germany), which looks similar to a vial containing bupivacaine 5 mg/ml (Actavis Group hf, Hafnarfjördur, Iceland). (figure 1). Vials of dobutamine are normally not present in the operation theatre. It was added to the anesthesia trolley, but not used, because of a previous patient that was severely cardiac compromised. Having noted the error, and with vital signs returned to normal, a continuous epidural infusion of bupivacaine 0.125% with
3 sufentanil 1µg/ml was started at 8 ml/h. No cardiac output was measured during anesthesia. Further surgery and anesthesia were uneventful, and the patient was observed in the recovery room for 180 minutes, during which vital signs remained stable. Postoperative analgesia was adequate, with a sensory block from Th6-Th12. Physical examination of the legs showed normal sensory and motor function. The postoperative 12 leads ECG showed no changes compared to the preoperative 12 leads ECG, postoperative troponines at 0 and 6 hours was beneath the reference value. The patient had an uneventful recovery with full mobilisation until discharge from the hospital ten days later. Related sequelae of inadvertant epidural injections range from none or reversible effects to debilitating irreversible neurological damage. 1,2 Recommendations to prevent drug errors are easily found elsewhere and are beyond the scope of this report.,3,4 To prevent medication errors, hospital regulatings now stipulate that any syringe containing medication should be checked and signed for by two independent health care providers. However, since drug errors will probably never be completely eliminated, we believe it is important to report any inadvertent epidural injection with a drug that has not been previously reported. To our knowledge, while reports on epidural injections of other inotropic drugs have been published, ours is the first to describe recovery following accidental epidural injection of dobutamine. The solution injected is this case is registered as Dobutamine-hameln and contains 250 mg of dobutamine per 50 ml vial, with addition of sodiummetabisulfate, sodiumchloride, and hydrochloric acid in aqueous solution. The immediate effects of the epidural injection of dobutamine in our patient may be explained by quick absorption from the epidural space into the systemic circulation. Presumably, despite the vasodilation effect of dobutamine, β 1 stimulation of the heart produced a significant increase in heart rate and cardiac output with
4 subsequent rise in blood pressure. The fact that dobutamine was injected epidurally may have attenuated the peak effects compared to a similar intravenous dose. It may have also resulted in prolonged duration of action, which is at odds with the elimination half-life of dobutamine of less than three minutes. 5 The favourable outcome in our patient may be in part due to the relatively weak α receptor action and vasodilation effects of β receptor stimulation. Spinal injection of inotropic drugs with strong α receptor action has been shown to induce severe vasoconstriction, resulting in spinal cord ischemia. 6 In conclusion, while the inadvertent epidural injection of 25 mg of dobutamine resulted in temporary tachycardia and hypertension, recovery was uneventful and no long term complications were seen. This favorable outcome may be reassuring in case of any future inadvertent epidural injection of dobutamine.
5 References 1. Hew CM, Cyna AM, Simmons SW. Avoiding inadvertent epidural injection of drugs intended for non-epidural use. Anaesth Intensive Care 2003;31 (1):44-9 2. Abeysekera A, Berman IJ, Kluger MT, Short TG. Drug error in anaesthetic practice: a review of 896 reports from the Australian Incident Monitoring Study database. Anaesthesia 2005;60(3):220-7 3. Mulroy MF, Norris MC, Liu SS. Safety steps for epidural injection of local anesthetics: review of the literature and recommendations. Anesth Analg 1997:85(6):1346-56 4. Jensen LS, Merry AF, Webster CS, Weller J, Larsson L. Evidence-based strategies for preventing drug administration errors during anaesthesia. Anaesthesia 2004;59(5):493-504 5. Rang HP, Dale MM, Ritter JM, Flower RJ. Rang and Dale s Pharmacology, 6th edition. Elsevier Health Science Division 6. Dohi S, Matsumiya N, Takeshima R, Naito H. The effects of subarachnoid lidocaine and phenylephrine on spinal cord and cerebral blood flow in dogs. Anesthesiology 1984;61(3):238-40 Figure Legend
6 Figure 1. Bupivacaine and dobutamine vials
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