Shields John A
Vanderbilt University Medical Center, Nashville, Tennessee, USA.
AANA J. 2008 Feb;76(1):41-5.
Heart block and Q-Tc interval prolongation have been reported with several agents used in anesthesia, and the US Food and Drug Administration mandates evaluation of the Q-T interval with new drugs. Drug-induced Q-T interval prolongation may precipitate life-threatening arrhythmias, is considered a precursor for torsades de pointes, and may predict cardiovascular complications. In the patient described in this article, heart block occurred and the Q-Tc interval became prolonged after muscle relaxant reversal with neostigmine; both were considered to be related to the combination of agents used in the case, as well as to other predisposing factors such as morbid obesity. The agents used that affected cardiac conduction were neostigmine, desflurane, droperidol, dolasetron, and dexmedetomidine. Although the heart block was resolved after 2 doses of atropine, prolonged P-R and Q-Tc intervals persisted into the immediate postoperative period but returned to baseline within 4 hours. Clinical implications of this report include increasing awareness of the multitude of factors affecting Q-T interval prolongation during anesthesia.
已有报道称，多种麻醉用药可导致心脏传导阻滞和Q-Tc间期延长，美国食品药品监督管理局要求对新药进行Q-T间期评估。药物诱发的Q-T间期延长可能会引发危及生命的心律失常，被视为尖端扭转型室速的先兆，并且可能预示心血管并发症。在本文所述病例中，使用新斯的明逆转肌松作用后出现了心脏传导阻滞，Q-Tc间期延长；这两者均被认为与该病例中使用的联合用药有关，也与其他易感因素如病态肥胖有关。影响心脏传导的药物有新斯的明、地氟醚、氟哌利多、多拉司琼和右美托咪定。尽管给予2剂阿托品后心脏传导阻滞得以缓解，但P-R间期和Q-Tc间期延长持续至术后即刻，但在4小时内恢复至基线水平。本报告的临床意义包括提高对麻醉期间影响Q-T间期延长的多种因素的认识。
