When I lecture, in reference to acute surgical pain, it is important to remember to continue pain medication throughout the inflammatory process to prevent chronic pain from forming. How long do we treat? Depends on the duration of inflammation. You want to treat throughout the inflammatory process. It is positively NOT contraindicated to treat and OHE for at least several days.
Castration
Preoperative:
■ Neuroleptanalgesia to include opioid + acepromazine (0.01–0.05 mg/kg) OR alpha2 +/– ketamine (5–10 mg/kg IM: the higher doses are selected for cats that
are more dicult to handle)
■ Induction of anaesthesia: In some cats an opioid, an alpha2 adrenoceptor agonist and ketamine will provide sucient analgesia and anaesthesia for a castration
• Intravenous: Propofol to eect (3–10 mg/kg), ketamine (3–5 mg/kg) + diazepam or midazolam (0.25 mg/kg), or alfaxalone (3–5 mg/kg). Note: if an alpha2
adrenoceptor agonist has been used preoperatively these doses may be lower
• Intramuscular: An alpha2 adrenoceptor agonist + ketamine (5–10 mg/kg) or tiletamine/zolazepam (3–4 mg/kg).
Maintenance of anaesthesia: Inhalation anaesthesia or ketamine or propofol or alfaxalone IV to eect. Note: in many cases a castration can be completed without
the need for maintenance anaesthesia drugs; however, there should be a plan for extending the anaesthesia time in the event the cat becomes responsive or
complications arise. Equipment should also be available for endotracheal intubation.
Local anaesthetic techniques: Intra-testicular block and pre- and/or post-surgery skin inltration with lidocaine.
Postoperative analgesia: NSAID.
Ovariohysterectomy/ovariectomy
Preoperative:
■ Analgesia: Opioid ± ketamine (5–10 mg/kg IM: the higher doses are selected for cats that are more dicult to handle)
■ Sedation: Acepromazine (0.01–0.05 mg/kg IM) or alpha2 adrenoceptor agonist
■ Induction of anaesthesia:
• Intravenous: Propofol to eect (3–10 mg/kg), ketamine (3–5 mg/kg) + diazepam or midazolam (0.25 mg/kg), or alfaxalone (3–5 mg/kg). Note: if an
alpha2 adrenoceptor agonist has been used preoperatively these doses may be lower
• Intramuscular: An alpha2 adrenoceptor agonist + ketamine (5–10 mg/kg) or tiletamine/zolazepam (3–4 mg/kg).
Maintenance of anaesthesia: Inhalation anaesthesia or ketamine or propofol or alfaxalone IV to eect (1/3 or 1/2 of initial dose).
Note: in many cases an ovariohysterectomy or ovariectomy can be completed without the need for maintenance anaesthesia drugs; however, there should be a plan
for extending the anaesthesia time in the event the cat becomes responsive or complications arise; venous access is recommended.
Local anaesthetic techniques: Incisional and intraperitoneal/ovarium ligament block with lidocaine.
Postoperative analgesia: NSAID.
These are directly from the WSAVA GPC Pain Treatise published in the Journal of Small Animal Practice and is available for open access at the GPC pages of
www.wsava.org.