General anaesthesia in Pugs

by Jan Mylemans D.V.M.

General anaesthesia in Pugs is best given under intubation :

     Before the anaesthesia is induced, the Pug is given Atropin subcutaneous at a dose of 0.04 mg per kg bodyweight.
     Ten minutes later a cocktail of 0.4 mg Methadon + 0.4 mg Acepromazine intramuscular per kg bodyweight.
     Ten minutes later the larynx is sprayed with xylocain-spray to avoid reactions by introducing the tracheotube in the
     larynx and the trachea. When this is done successfully, the tracheotube is connected to the anaesthesia-machine which
     provides a mixture of isoflurane and medical oxygen, in a concentration of 3% isoflurane and 97% oxygen at the
     beginning of the general anaesthesia and this concentration is augmented or lowered in function of the degree of pain
     reaction by testing for pain feeling on the Pug.

This method permits a surgery as long as necessary, with a mortal risk of 3 pro mille, this in opposite to classic intravenous
barbiturate anaesthesia where the mortal risk is much higher (up to 25 % !).

The current trend in veterinary medicine is to replace halothane by isoflurane, as explained in the following note sent on
October 9th, 1995, by

Ron Mandsager, DVM
     Diplomate, American College of Veterinary Anesthesiologists
     Asst. Professor, Anesthesiology
     Dept. of Medicine & Surgery
     College of Veterinary Medicine
     Oklahoma State University
     Stillwater, OK, USA

     "Fluothane (a trade name for halothane) is still widely used for anaesthesia in veterinary medicine in the United
     States. However, many veterinarians are making a transition to using isoflurane instead of halothane or
     methoxyflurane - although all three inhalant anaesthetics are available.

     Advantages of isoflurane over halothane include:
          Slightly faster inductions and recoveries,
          Lowered incidence of cardiac arrhythmias,
          Better maintenance of cardiac output,
          No metabolism, with less potential for toxicity (such as halothane hepatitis).

     Disadvantages of isoflurane over halothane:
          Much more expensive,
          More respiratory depression."