Electroacupuncture in trans and postoperative analgesia in bitches submitted to ovariosalpingohisterectomy

Thirty-six dogs undergoing elective ovariohysterectomy surgery were randomly distributed into 3 groups of 12 animals each. In the first group, dense-dispersed electroacupuncture was performed with a frequency of 3-200 Hz in SP4, ST44, KID3 points and 1.5mL of saline was given intramuscularly (GEA group). For the second group, dense-dispersed electroacupuncture was performed with a frequency of 3200 Hz in SP6, ST36, GB34 points and 1.5mL of saline given intramuscularly (GEB group). In the third group acupuncture was performed in 3 false points being the electroacupuncture device attached to the needles but not connected, and morphine was also administered at a dose of 0.5mg/kg diluted in saline so that the total volume was 1.5mL intramuscularly (GF group). Cardiovascular and respiratory parameters were evaluated during the pre and perioperative period. The evaluation of pain and postoperative sedation was performed for 12 hours and analgesic supplementation was performed whenever the pain score reached values above or equal to 9 points (in a total of 27) in accordance with the Scale of Pain of the University of Melbourne (EDUM). The GEB group had stable blood pressure and lower Et-iso value as well as less need for additional analgesia postoperatively. The GEA group showed the highest values of Etiso and showed the greatest need for additional analgesia in the immediate postoperative period (at the moment of extubation). The GF group required more supplementary analgesia postoperatively and showed higher sedation scores up to 4 hours after surgery. The KID3, ST44 and SP4 acupoints used in electroacupuncture with frequency 3-200 Hz are not able to promote satisfactory antinociceptive action in the perioperative period. Postoperative analgesic effect, promoted by electrical stimulation in acupoints KID3, ST44 and SP4, is inferior to that provided by acupoints ST36, SP6 and GB34 and superior to that obtained with morphine.