Ventricular fibrillation after accidental injection of bupivacaine into the pericardium

Abstract

SummaryA postoperative cardiac surgical patient developed ventricular Jibrillation immediately after accidental pericardial injection of bupivacaine at room temperature. The possible causes, which include systemic toxicity. local vasoconstriction with myocardial ischaemia. local toxic effect of bupivacaine or local hypothermia, are discussed. Key wordsToxicity; bupivacaine. Anaesthetic techniques. regional; interpleural block. Heart; ventricular fibrillation.The use of interpleural bupivacaine for analgesia in acute and chronic pain has been reported since 1984. The technique is effective after upper abdominal surgery, but only variably so after thoracotomy [I]. It is thought to work by diffusion of local anaesthetic through the parietal pleura and intercostal muscles, thus blocking the intercostal nerves (dermatomes T, to T,J. The recommended doses of bupivacaine for interpleural analgesia are 20--30 ml in a 0.5 to 0.75% concentration. For treatment of postoperative pain which is resistant to opioids, we have used bupivacaine 0.125% injected into the pleural drain while it is briefly clamped. We report a patient where bupivacaine was accidentally injected through a pericardial drain, with resultant ventricular fibrillation. Case historyA 64-year-old man had a history of two myocardial infarctions. Left ventricular function was good but coronary angiography showed triple vessel disease. Uneventful complete surgical revascularisation was performed and a left pleural and a pericardial drain were left in situ. On the first postoperative day the patient was haemodynamically stable and his pain was treated with piritramide 15 mg intramuscularly. However, on the second day the pain was resistant to this treatment and plain bupivacaine 0.125% 20 ml (25 mg) was injected into the clamped left pleural drain. After 15 min the pain had not diminished, therefore it was decided to inject an additional bolus of bupivacaine 0.125% 10 ml (12.5 mg) interpleurally. However this bolus was inadvertently injected into the pericardial drain, at which point the patient developed ventricular fibrillation. A single D C shock was sufficient to restore sinus rhythm and stable haemodynamics and there were no further cardiac or neurological complications. DiscussionSeveral physiological mechanisms can explain the occurrence of ventricular fibrillation after injection of bupivacaine at room temperature into the pericardial sac.First of all, a local toxic reaction of bupivacaine on epicardial fibres, or perhaps rapid absorption into the coronary arteries, could be responsible for life-threatening arrhythmias. The electrophysiological effect of bupivacaine on myocardial cells results from an interaction with the fast sodium channels in the cardiac membrane [2]. This phenomenon decreases the maximum rate of depolarisation, the amplitude and duration of the action potential and shortens the effective refractory period. This may result in unidirectional conduction delay, ventricular arrhythmias and fibrillation.Secondly, rapid systemic absorption ...

Hemodynamic Effects of Interpleural Lidocaine and Bupivacaine Combination in Anesthetized Dogs with and Without an Open Pericardium

“…Electrolyte concentrations were within normal reference intervals before anesthesia and dogs were administered a maintenance fluid rate of lactated Ringer's solution. Cardiac arrhythmias have been reported in conscious sheep and lightly anesthetized cats when systemic toxic doses of bupivacaine were administered, and in humans after induction of regional nerve blocks 29–32 . General anesthesia and analgesia may have blunted the electrophysiologic response we recorded by suppressing sympathetic nervous system activation caused by bupivacaine or by providing potent vagolytic activity 19,38,46,47 …”

“…Systemic toxicity to bupivacaine is seemingly species specific 29–31 . Ventricular fibrillation after accidental injection of bupivacaine into the pericardium has been reported in a human patient with a history of 2 myocardial infarctions 32 . There have been no controlled studies in dogs assessing the safety of this technique with an open pericardium.…”