title: Evaluation of the repeatability of rhinomanometry and its use in assessing transnasal resistance and pressure in dogs.
abstract: OBJECTIVE
  To evaluate a modified posterior rhinomanometric method for clinical application in dogs.
  
  
  METHODS
  15 healthy Beagles and 8 Bulldogs (4 healthy and 4 with respiratory problems).
  
  
  METHODS
  Rhinomanometry was performed 3 times within a 15-minute period in anesthetized dogs. Transnasal pressure (P(NA)) and nasal resistance (R(NA)) were determined by use of artificial airflow (adjusted for body weight) for inspiration (P(NAin) and R(NAin), respectively) and expiration (P(NAout) and R(NAout)). Procedures were repeated for the Beagles 7 days later.
  
  
  RESULTS
  For the Beagles, mean +/- SD of P(NAin) for both days (0.162 +/- 0.042 kPa) was significantly lower than P(NAout) (0.183 +/- 0.053 kPa). Similarly, R(NAin) (1.47 +/- 0.41 kPa/[L/s]) was significantly lower than R(NAout) (1.64 +/- 0.46 kPa/[L/s]). Pairwise comparison of values for P(NA) and R(NA) for the 2 days revealed no significant difference. Repeatability of the method (estimated as within-day variation) for R(NA) was +/- 0.19 kPa/(L/s), whereas variation between the days was +/- 0.36 kPa/(L/s) for R(NAin) and +/- 0.44 kPa/(L/s) for R(NAout). The 4 clinically normal Bulldogs had R(NA) values ranging from 1.69 to 3.48 kPa/(L/s), whereas in the 4 Bulldogs with respiratory problems, R(NA) ranged from 9.83 to 20.27 kPa/(L/s).
  
  
  CONCLUSIONS
  R(NA) is inversely dependent on body size and nonlinearly associated with airflow. We propose that R(NA) in dogs should be determined for airflows standardized on the basis of body size. The P(NA) and R(NA) in Beagles can be measured with sufficient repeatability for clinical use and nasal obstructions are detectable.
authors.affiliation: Equine Hospital, Vetsuisse Faculty, University of Zurich, Zurich CH-8057, Switzerland.
authors.forename: Thomas S
authors.initials: TS
authors.lastname: Wiestner
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Koch
authors.forename: Natascha
authors.initials: N
authors.lastname: Nad
authors.forename: Aaron
authors.initials: A
authors.lastname: Balli
authors.forename: Malgorzata
authors.initials: M
authors.lastname: Roos
authors.forename: Richard
authors.initials: R
authors.lastname: Weilenmann
authors.forename: Erika
authors.initials: E
authors.lastname: Michel
authors.forename: Susanna
authors.initials: S
authors.lastname: Arnold
mesh_terms: D000403:Airway Resistance / Q000502:physiology*; D000818:Animals; D004283:Dog Diseases / Q000175:diagnosis*; D004285:Dogs; D005260:Female; D008297:Male; D015508:Nasal Obstruction / Q000175:diagnosis / Q000662:veterinary*; D015203:Reproducibility of Results; D025363:Rhinomanometry / Q000662:veterinary*