title: The electrocardiogram of anaesthetized southern sea lion (Otaria flavescens) females.
abstract: OBJECTIVE
  The goal of this study was to characterize for the first time the electrocardiogram (ECG) of the southern sea lion (SSL) Otaria flavescens.
  
  
  METHODS
  Thirteen wild SSL females were captured at Isla de Lobos (Uruguay) and anaesthetized with isoflurane. Electrocardiographic recording was performed on anaesthetized animals at ventral recumbence following standardized procedures.
  
  
  RESULTS
  The ECG recordings showed normal sinus rhythm. Amplitude and duration of P and T waves, QRS complex, PR interval, QT interval and ST segment (STS) were determined for all animals in all leads. QT corrected was determined in lead II. P wave polarity was consistent among animals (positive in LI, LII, LIII and AVF leads and negative in AVL and AVR leads for all animals), but T wave polarity did not present any constant pattern among animals, being either positive, negative or biphasic in different leads and different animals. The PR interval (0.15 ± 0.2 s) was similar to the allometric prediction for most of mammalian species including humans. The STS were normal in 10 of the SSL but showed STS depression in three of the animals. Almost all animals had a negative electrical axis (-30° to -120°), with one exception that showed a positive electrical axis (120°). Mean eupnoeic heart rate was 104.61 ± 10.06 (range = 88-120) beats per minute.
  
  
  CONCLUSIONS
  This study was the first ECG description for this species, and provides valuable information for cardiac monitoring during anaesthesia.
authors.affiliation: Instituto de Investigaciones Marinas y Costeras, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata-CONICET, Funes 3350, (7600) Mar del Plata, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas, Rivadavia 1917, PB (C1033AAJ) Ciudad Autónoma de Buenos Aires, Argentina. Electronic address: marieladassis@gmail.com.
authors.forename: M
authors.initials: M
authors.lastname: Dassis
authors.affiliation: Instituto de Investigaciones Marinas y Costeras, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata-CONICET, Funes 3350, (7600) Mar del Plata, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas, Rivadavia 1917, PB (C1033AAJ) Ciudad Autónoma de Buenos Aires, Argentina.
authors.forename: D H
authors.initials: DH
authors.lastname: Rodríguez
authors.affiliation: Departamento de Sanidad Animal y Medicina Preventiva, Facultad de Ciencias Veterinarias, Universidad Nacional del Centro de la Provincia de Bs As, CONICET - Unidad Ejecutora CIVETAN, Ciencias Veterinarias de Tandil, Pje. Arroyo Seco, s/n, (7000) Tandil, Argentina.
authors.forename: E
authors.initials: E
authors.lastname: Rodríguez
authors.affiliation: Departamento Mamíferos Marinos, Dirección Nacional de Recursos Acuáticos (DINARA), Ministerio de Ganadería, Agricultura y Pesca, Constituyente 1497, (C.P. 11200) Montevideo, Uruguay.
authors.forename: A
authors.initials: A
authors.lastname: Ponce de León
authors.affiliation: Departamento de Fisiopatología, Facultad de Ciencias Veterinarias, Universidad Nacional del Centro de la Provincia de Bs. As., CONICET - Unidad Ejecutora CIVETAN, Ciencias Veterinarias de Tandil, Pje. Arroyo Seco, s/n, (7000) Tandil, Argentina.
authors.forename: E
authors.initials: E
authors.lastname: Castro
mesh_terms: D018685:Anesthetics, Inhalation; D000818:Animals; D000835:Animals, Wild; D004562:Electrocardiography / Q000662:veterinary*; D005260:Female; D007530:Isoflurane; D012016:Reference Values; D046070:Sea Lions
chemical_list: D018685:Anesthetics, Inhalation; D007530:Isoflurane
keywords: Dive physiology; Electrocardiography; Isoflurane anaesthesia; Pinnipeds