title: Chronic left heart catheterization for microvascular blood flow determination in the rabbit: a minimally invasive technique using specially designed port devices.
abstract: BACKGROUND
  This study describes a modified catheterization technique with subcutaneously implanted port catheters to be inserted in a retrograde manner across the aortic valve into the left heart ventricle through the right carotid artery to measure organ perfusion.
  
  
  METHODS
  The specially designed arterial port catheters were implanted in New Zealand rabbits (n = 11, 3.7 +/- 0.1 kg [mean +/- SEM]) under iv anesthesia (medetomidine/ketamine) and single-shot perioperative antibiotic therapy. Hemodynamics were registered continuously during the operation via an ear artery catheter.
  
  
  RESULTS
  Implantation of ports was performed in all animals (11/11) without major complications (mean operation time: 70 +/- 3 min). We did not observe catheter-associated arrhythmia, fall in mean arterial pressure (MAP before and post OP: 70 +/- 2 and 68 +/- 2 Torr, respectively), or change in arterial oxygen saturation (SaO2 before and post OP: 89 +/- 3 and 95 +/- 2%, respectively). With a specifically modified microsurgical insertion technique, cerebral blood supply was effectively preserved as evidenced from postmortem histological examinations, cerebral blood flow determination with fluorescent microspheres, and measurement of S-100b protein serum concentrations, a specific marker of neuronal damage. The positioning of the catheter tip in the left ventricle was found to be correct in 10/11 animals.
  
  
  CONCLUSIONS
  Repeated and atraumatic microsphere injections into the left ventricle have become feasible by transcutaneous puncture of subcutaneous port systems over several weeks under light sedation. Hence, this new approach (i) avoids the necessity of repeated intracardiac injections and port insertions via thoracotomy, thus reducing the perioperative stress for the animals, and (ii) allows for the first time minimally invasive repetitive and chronic measurements of regional organ blood flow under various experimental settings.
authors.affiliation: Department of Surgery, Klinikum Grosshadern, Germany.
authors.forename: Johannes N
authors.initials: JN
authors.lastname: Hoffmann
authors.forename: Sonja
authors.initials: S
authors.lastname: Steinhagen
authors.forename: Christina
authors.initials: C
authors.lastname: Kast
authors.forename: Heinz P
authors.initials: HP
authors.lastname: Scheuber
authors.forename: Marianne
authors.initials: M
authors.lastname: Jochum
authors.forename: Cornelia
authors.initials: C
authors.lastname: Gippner-Steppert
authors.forename: Dietrich
authors.initials: D
authors.lastname: Inthorn
authors.forename: Friedrich W
authors.initials: FW
authors.lastname: Schildberg
authors.forename: Dirk
authors.initials: D
authors.lastname: Nolte
mesh_terms: D000818:Animals; D001794:Blood Pressure; D006328:Cardiac Catheterization / Q000295:instrumentation* / Q000379:methods*; D002408:Catheters, Indwelling; D002560:Cerebrovascular Circulation / Q000502:physiology; D003326:Coronary Circulation / Q000502:physiology*; D006352:Heart Ventricles; D008833:Microcirculation / Q000502:physiology; D008863:Microspheres; D019060:Minimally Invasive Surgical Procedures / Q000379:methods; D010100:Oxygen / Q000097:blood; D018962:Phlebotomy / Q000295:instrumentation / Q000379:methods; D011817:Rabbits
chemical_list: D010100:Oxygen