[Geometry and function of the dog nose: how does function change when form of the nose is changed?]. / Geometrie und Funktion der Hundenase: Wie ändert sich die Funktion, wenn die Form verändert wird?

Nasal airflow resistance in brachycephalic dogs is significantly elevated compared to normal dogs. LaserAssisted TurbinEctomy (LATE)-surgery as well as xylometazolin were shown to reduce pathologically increased intranasal airway resistance in brachycephalic dogs by approximately 50 %. Impulse oscillometry provides a reliable and sensitive method to examine intranasal stenoses in the canine nose. Acoustic rhinometry allows assessment of changes in cross sectional area and volume of the canine nasal cavity.

[Brachycephaly in dog and cat: a "human induced" obstruction of the upper airways]. / Brachyzephalie bei Hund und Katze: eine "menschengemachte" Obstruktion der oberen Atemwege.

Selective breeding for exaggerated features caused in many brachycephalic dog and cat breeds virtually a loss of the nose, with serious anatomical and functional consequences. In addition to respiratory and olfactory tasks, in dogs the nose is of vital importance for thermoregulation. As obligatory nose breathers, dogs suffer far more than humans when their nasal ventilation is restricted. An open discussion in the broad public has to motivate authorities and kennel clubs to recognize extreme brachycephalic breeding as seriously affecting animal health and welfare.

Structural characteristics of the nose in brachycephalic dog breeds analysed by computed tomography. / Strukturelle Besonderheiten der Nase brachyzephaler Hunderassen in der Computertomographie.

INTRODUCTION AND OBJECTIVE: In brachycephalic dogs breeds exaggerated and incorrect breed selection has led to overemphasis of brachycephaly and almost complete loss of the nose. This structural deformity causes severe malfunction of the airway and thus brachycephalic airway syndrome (BAS). It was the aim of this study to examine the anatomical specifics of the brachycephalic nose by computed tomography (CT) and to compare them to those of the normocephalic nose. METHODS: A total of 23 brachycephalic dogs (11 pugs, seven French Bulldogs, five English Bulldogs) and one normocephalic German Shepard dog as reference were examined. Multislice CT images of all animals were analysed. First multisclice images of both nose types were generated. Then, to compare structural differences to normocephalic breeds and among brachycephalic breeds, anatomical parameters were recorded and derived. RESULTS: Extreme shortening of the craniofacial skull and thus of the nasal cavity leads to abnormal configuration of the conchae. Two main types of aberrant conchal growth have been described: 1. rostral, aberrant conchae obstructing the nasal passage (RAC) and 2. caudal aberrant conchae obstructing the choanae (CAC). Furthermore, these conchae are characterised by a low degree of branching and crude lamellae. Measurements of the skull revealed characteristic differences among the brachycephalic dog breeds. The pug had an even shorter craniofacial skull than the French and English Bulldogs. CONCLUSION: The severe intranasal deformities in brachycephalic dogs described here for the first time are the basis for a new pathophysiologic understanding of BAS. CLINICAL RELEVANCE: Detailed structural analysis of aberrant, stenosing conchae (RAC, CAC) is an indispensable prerequisite for the development of an intranasal surgical therapy of BAS in the form of partial laser-assisted turbinectomy (LATE therapy).

[Old and new alpha 2-adrenoceptor agonists. 1. Xylazine and medetomidine]. / Alte und neue alpha 2-Adrenozeptor-Agonisten. Teil 1: Xylazin und Medetomidin.

The "discovery" of alpha 2-receptors permits the explanation of the mechanism of xylazine that was hitherto poorly understood. The substance can be classified as an alpha 2-adrenoceptor agonist. In the near future two new alpha 2-adrenoceptor agonists will be available in Germany: medetomidine for small animals and detomidine for large animals. Also a new alpha 2-adrenoceptor antagonist will be introduced: atipamezole. alpha 2-adrenoceptor agonists cause sedation, analgesia and muscle relaxation. Notable side effects are bradycardia, heart block and a dose dependent respiratory depression. A comprehensive survey on the pharmacology of the alpha 2-adrenoceptor agonists is given. The previous literature is summarized and discussed, including own studies and clinical experience. An attempt is made to assess the clinical importance of the new drugs. For certain indications medetomidine alone may not be satisfying and combination with other drugs becomes necessary. If sedation is inadequate, the combination with benzodiazepines or propofol is advised; if analgesia is poor, the combination with ketamine or an opioid is recommended.

[Anesthesia of horses with xylazine and ketamine. 2. Anesthesia in adult horses]. / Ein Beitrag zur Anästhesie des Pferdes mit Xylazin und Ketamin. Teil 2: Die Anästhesie des adulten Pferdes.

Xylazine and Ketamine were used for anaesthesia in 250 adult horses. This combination is useful both for induction and maintenance of anaesthesia. The induction with Xylazine and Ketamine has been successful not only with foals but also with high risk patients such as horses with colic. During the maintenance of anaesthesia Xylazine/Ketamine can be used with injectable anaesthetics as well as with volatile anaesthetics at the same time. A form of injection anaesthesia for short-time surgical procedures like castration and wound repair is presented. The maintenance of a Thiobarbiturate/Guaifenesin anaesthesia with Xylazine/Ketamine seems to be suitable for field conditions.

[Anesthesia of horses with xylazine and ketamine. 1. Anesthesia of foals]. / Ein Beitrag zur Anästhesie des Pferdes mit Xylazin und Ketamin. Teil 1: Die Anästhesie des Fohlens.

The anaesthesia with Xylazine and Ketamine in 24 foals is described. Special qualities of this form of anaesthesia and dosages for foals of different age are discussed. The combination of Xylazine and Ketamine is well suited for the anaesthesia of foals of all age and risk-groups. The induction takes place quickly and calmly, without signs of cardiorespiratory depression. The maintenance of anaesthesia is possible, without any problem, by repeated injection with Xylazine and Ketamine, as well as by inhalation anaesthesia with volatile anaesthetics. The recovery is short; the animals rise swiftly and safely. For these reasons we prefer, in foals, the anaesthesia with Xylazine and Ketamine to the induction and maintenance of anaesthesia with thiobarbiturates.