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→Local Anaesthesia
==Local Anaesthesia==
==Local Anaesthesia==
Local anesthesia (LA) can be used to provide intra- and postoperative analgesia. In contrast to human patients, dogs and cats are not amenable to LA if conscious. So, the techniques are used when the animal is under GA. <font color="red">****see surgical procedures for techqniue*****</font color><br><br>
Local anaesthesia (LA) can be used to provide intra- and postoperative analgesia. In contrast to human patients, dogs and cats are not amenable to LA if conscious. So, the techniques are used when the animal is under GA. <font color="red">****see surgical procedures for techqniue*****</font color><br><br>
When given prior to the start of a procedure, the use of LA may reduce the requirement for GA drugs during surgery. When given at the end of a procedure, prior to GA recovery, they will provide postoperative analgesia.<br><br>
When given prior to the start of a procedure, the use of LA may reduce the requirement for GA drugs during surgery. When given at the end of a procedure, prior to GA recovery, they will provide postoperative analgesia.<br><br>
Useful techniques in the oral cavity include [[Local Infiltration|'''infiltration anesthesia''']] and [[Specific Nerve Blocks|'''regional nerve blocks''']].<br><br>
Useful techniques in the oral cavity include [[Local Infiltration|'''infiltration anaesthesia''']] and [[Specific Nerve Blocks|'''regional nerve blocks''']].<br><br>
All clinically used local anesthetics are '''membrane-stabilizing agents'''. They prevent depolarization and thus stop or retard conduction of impulses. Sensation disappears in the following order: pain, cold, warmth, touch, joint and deep pressure. [[Local Anaesthetics#procaine|'''Procaine hydrochloride''']] is the prototype of all local anesthetics. It is the standard drug for comparison of anesthetic effects. For LA in the oral cavity [[Local Anaesthetics#Lidocaine|'''lidocaine]], [[Local Anaesthetics#Mepivicaine|mepivacaine]],[[Local Anaesthetics#Bupivacaine| bupivacaine]] and ropivacaine''' are all suitable. The local anesthetic drug chosen for postoperative pain relief should ideally have a long duration of action, and therefore [[Local Anaesthetics#Bupivacaine|'''bupivacaine ''']](onset 15 minutes, duration 4–6 hours) '''is the drug of choice'''. Lidocaine can be used during surgery for more immediate effect.<br><br>
All clinically used local anaesthetics are '''membrane-stabilizing agents'''. They prevent depolarization and thus stop or retard conduction of impulses. Sensation disappears in the following order: pain, cold, warmth, touch, joint and deep pressure. [[Local Anaesthetics#procaine|'''Procaine hydrochloride''']] is the prototype of all local anesthetics. It is the standard drug for comparison of anesthetic effects. For LA in the oral cavity [[Local Anaesthetics#Lidocaine|'''lidocaine]], [[Local Anaesthetics#Mepivicaine|mepivacaine]],[[Local Anaesthetics#Bupivacaine| bupivacaine]] and ropivacaine''' are all suitable. The local anaesthetic drug chosen for postoperative pain relief should ideally have a long duration of action, therefore [[Local Anaesthetics#Bupivacaine|'''bupivacaine ''']](onset 15 minutes, duration 4–6 hours) '''is the drug of choice'''. Lidocaine can be used during surgery for a more immediate effect.<br><br>
==Mechanism of Action==
==Mechanism of Action==