title: Hemodynamic and cardiac electrophysiologic effects of lidocaine-bupivacaine mixture in anesthetized and ventilated piglets.
abstract: BACKGROUND
  The sensory blockade induced by a lidocaine-bupivacaine mixture combines the faster onset of lidocaine and the longer duration of bupivacaine. The current study compared the effects of large doses lidocaine (16 mg/kg), bupivacaine (4 mg/kg), and a mixture of 16 mg/kg lidocaine-4 mg/kg bupivacaine on hemodynamic and cardiac electrophysiologic parameters in anesthetized and ventilated piglets.
  
  
  METHODS
  After carotid artery cannulation, a double micromanometer measured mean aortic pressure, left ventricular end diastolic pressure, and the first derivative of left ventricular pressure. Electrocardiogram recording and a bipolar electrode catheter measured RR, PQ, QRS, QT C, JT C, AH, and HV intervals. Lidocaine, bupivacaine, or the mixture was administered intravenously over 30 s, and studied parameters were measured throughout 30 min.
  
  
  RESULTS
  Mean aortic pressure decreased in all groups ( P < 0.05). The first derivative of left ventricular pressure was decreased in all groups ( P < 0.001) but to a greater extent with the mixture compared with lidocaine ( P < 0.04). RR, QT C, and JT C intervals were similarly increased in all groups ( P < 0.05). In all groups, PQ, AH, HV, and QRS intervals were widened ( P < 0.001). The lengthening of PQ was greater with bupivacaine ( P < 0.02). The lengthening of AH was greater and delayed with bupivacaine compared with lidocaine ( P < 0.03). The lengthening of HV and the widening of QRS were greater and delayed with bupivacaine ( P < 0.01). The widening of QRS was greater with the mixture than with lidocaine ( P < 0.01).
  
  
  CONCLUSIONS
  The alterations of ventricular conduction parameters are greater with 4 mg/kg bupivacaine than with a mixture of 16 mg/kg lidocaine-4 mg/kg bupivacaine, whereas the hemodynamic parameters are similarly altered.
authors.affiliation: Division of Anesthesiology, Critical Care, Pain, and Emergency, Department of Anesthesiology, Clinique Val d'Aurel Paul Lamarque, Montpellier, France.
authors.forename: Jean-Yves
authors.initials: JY
authors.lastname: Lefrant
authors.forename: Laurent
authors.initials: L
authors.lastname: Muller
authors.forename: Jean E
authors.initials: JE
authors.lastname: de La Coussaye
authors.forename: Laurent
authors.initials: L
authors.lastname: Lalourcey
authors.forename: Jacques
authors.initials: J
authors.lastname: Ripart
authors.forename: Pascale A
authors.initials: PA
authors.lastname: Peray
authors.forename: Xavier
authors.initials: X
authors.lastname: Mazoit
authors.forename: Michel
authors.initials: M
authors.lastname: Dauzat
authors.forename: Antoine
authors.initials: A
authors.lastname: Sassine
authors.forename: Jean-Jacques
authors.initials: JJ
authors.lastname: Eledjam
mesh_terms: D000758:Anesthesia; D000779:Anesthetics, Local / Q000494:pharmacology*; D000818:Animals; D001835:Body Weight / Q000502:physiology; D002045:Bupivacaine / Q000008:administration & dosage / Q000494:pharmacology*; D004338:Drug Combinations; D004562:Electrocardiography / Q000187:drug effects; D004594:Electrophysiology; D006321:Heart / Q000187:drug effects*; D006339:Heart Rate / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects*; D007262:Infusions, Intravenous; D008012:Lidocaine / Q000008:administration & dosage / Q000494:pharmacology*; D012121:Respiration, Artificial; D013552:Swine
chemical_list: D000779:Anesthetics, Local; D004338:Drug Combinations; D008012:Lidocaine; D002045:Bupivacaine