title: The Effects of Local Anaesthetics on QT Parameters during Thoracic Epidural Anaesthesia Combined with General Anaesthesia: Ropivacaine versus Bupivacaine.
abstract: BACKGROUND
  Many studies focusing on the effects of local anaesthetics on QT intervals have been performed, but the articles evaluating the relationship between thoracic epidural anaesthesia combined with general anaesthesia and QT parameters are very limited.
  
  
  OBJECTIVE
  We aimed to compare the effects of bupivacaine and ropivacaine on QT interval, corrected QT, dispersion of QT, and corrected dispersion of QT in patients undergoing lung resection under thoracic epidural anaesthesia combined with general anaesthesia.
  
  
  METHODS
  Prospective clinical study.
  
  
  METHODS
  Thirty ASA physical status 1-3 patients requiring thoracic epidural anaesthesia combined with general anaesthesia for thoracic surgery. Patients were randomly assigned to two groups, which were allocated to receive either bupivacaine (Group B) or ropivacaine (Group R) during thoracic epidural anaesthesia. Following haemodynamic monitoring, a thoracic epidural catheter was inserted. Local anaesthetic at an average dose of 1.5 mL/ segment was given through an epidural catheter. The same general anaesthesia protocol was administered in both groups. Records and measurements were performed on 10 phases that were between the thoracic epidural catheter insertion to the 5(th) min of endobronchial intubation. In all phases, systolic arterial pressure, diastolic arterial pressure, mean arterial pressure, heart rate, peripheral O2 saturation, and electrocardiogram monitoring were performed in patients. All QT parameters were recorded by 12-lead electrocardiogram and analysed manually by a cardiologist.
  
  
  RESULTS
  QT intervals were similar between two groups. In Group R, corrected QT values at the 20(th) min of local anaesthetic injection and the 5(th) min of endobronchial intubation were shorter than those in Group B (p<0.05). The basal dispersion of QT and dispersion of QT values at the 1(st) min of propofol injection were shorter than those in Group R (p<0.05). The corrected dispersion of QT value at the 1(st) min of propofol injection was shorter in Group R (p<0.05). In Group R, the decrease in mean arterial pressure at the 1st min of fentanyl injection was significant compared with Group B (p<0.05). There was no significant difference between the groups with respect to heart rate and complications.
  
  
  CONCLUSIONS
  The corrected QT, dispersion of QT, and corrected dispersion of QT intervals were slightly longer in the patients receiving bupivacaine compared with those receiving ropivacaine in various phases of the present study.
authors.affiliation: Department of Anesthesiology and Reanimation, Atatürk Chest Diseases and Thoracic Surgery Education and Research Hospital, Ankara, Turkey.
authors.forename: Ozlem
authors.initials: O
authors.lastname: Güven
authors.affiliation: Department of Anesthesiology and Reanimation, Atatürk Chest Diseases and Thoracic Surgery Education and Research Hospital, Ankara, Turkey.
authors.forename: Hilal
authors.initials: H
authors.lastname: Sazak
authors.affiliation: Department of Anesthesiology and Reanimation, Atatürk Chest Diseases and Thoracic Surgery Education and Research Hospital, Ankara, Turkey.
authors.forename: Ali
authors.initials: A
authors.lastname: Alagöz
authors.affiliation: Department of Anesthesiology and Reanimation, Atatürk Chest Diseases and Thoracic Surgery Education and Research Hospital, Ankara, Turkey.
authors.forename: Eser
authors.initials: E
authors.lastname: Savkılıoğlu
authors.affiliation: Department of Anesthesiology and Reanimation, Atatürk Chest Diseases and Thoracic Surgery Education and Research Hospital, Ankara, Turkey.
authors.forename: Cilsem Sevgen
authors.initials: CS
authors.lastname: Demirbaş
authors.affiliation: Department of Cardiology, Harran University Faculty of Medicine, Şanlıurfa, Turkey.
authors.forename: Ali
authors.initials: A
authors.lastname: Yıldız
authors.affiliation: Department of Biostatistics, Hacettepe University Faculty of Medicine, Ankara, Turkey.
authors.forename: Erdem
authors.initials: E
authors.lastname: Karabulut
keywords: Bupivacaine; QT parameters; local anaesthetics; ropivacaine; thoracic epidural anaesthesia