Comparison of intraperitoneal ropivacaine and bupivacaine for postoperative analgesia in dogs undergoing ovariohysterectomy.

OBJECTIVE: To compare postoperative analgesia following either intraperitoneal (IP) ropivacaine or bupivacaine in dogs undergoing ovariohysterectomy (OVH) in the scope of multimodal analgesia. STUDY DESIGN: Prospective, randomized, blinded clinical study. ANIMALS: A total of 45 privately owned dogs undergoing OVH, aged 37 ± 28 months and weighing 11.3 ± 4.5 kg. METHODS: Dogs were premedicated with acepromazine (0.05 mg kg-1) and morphine (0.5 mg kg-1) intramuscularly (IM). Anaesthesia was induced with alfaxalone and maintained with isoflurane in oxygen. Carprofen (4 mg kg-1) was injected subcutaneously after intubation. Dogs were randomly assigned to receive either bupivacaine (group B; 3 mg kg-1) or ropivacaine (group R; 3 mg kg-1) IP prior to complete closure of the linea alba. At 0.5, 1, 2, 4, 6 and 8 hours after extubation, sedation and postoperative pain were assessed, using the short form of the Glasgow Composite Pain scale (GCPS-SF), a dynamic interactive visual analogue scale (DIVAS), and mechanical nociceptive threshold (MNT) measurement. Rescue morphine (0.2 mg kg-1) was administered in case of ≥ 5/20 or ≥ 6/24 in the GCPS-SF and/or >40 mm in the DIVAS. Parametric data were compared using the t test; nonparametric data were analysed with the two-sample Wilcoxon test (p < 0.05). RESULTS: The GCPS-SF score was significantly higher in group R at 8 hours. There was no other significant difference regarding sedation or analgesia between the groups. Rescue analgesia was administered to 15 dogs (R: 9/22; B: 6/22), with no significant difference between the groups. MNT values decreased in both groups at all time points when compared to baseline. No adverse effects were observed. CONCLUSIONS AND CLINICAL RELEVANCE: Ropivacaine or bupivacaine IP in combination with morphine IM and carprofen SC provided comparable postoperative analgesia in dogs after OVH for 6 hours. However, the anaesthetic protocol used did not prevent the administration of rescue analgesia in 41% of animals.

Intraperitoneal bupivacaine with or without incisional bupivacaine for postoperative analgesia in dogs undergoing ovariohysterectomy.

OBJECTIVE: Intraperitoneal (IP) bupivacaine provides postoperative analgesia in dogs undergoing ovariohysterectomy (OHE) alone or in combination with incisional (INC) bupivacaine. This study investigated whether the combination of INC and IP bupivacaine is superior to IP bupivacaine alone. STUDY DESIGN: Prospective, randomized, blinded clinical study. ANIMALS: Thirty-nine privately owned dogs undergoing OHE, aged 25 ± 23 months and weighing 11.8 ± 5.7 kg. METHODS: Dogs were premedicated with acepromazine (0.05 mg kg(-1) ) and morphine (0.5 mg kg(-1) ) intramuscularly (IM); anaesthesia was induced with propofol and maintained with isoflurane in oxygen. Carprofen (4 mg kg(-1) ) was administered subcutaneously (SC) after intubation. Bupivacaine (3 mg kg(-1) ) IP was administered before complete closure of the linea alba to all dogs. Dogs were randomly assigned into two groups: group B received bupivacaine (n = 20; 1 mg kg(-1) ) and group S received saline (n = 19; 0.2 mL kg(-1) ) INC as a subcutaneous 'splash' before skin closure. Postoperative analgesia was assessed with a dynamic interactive visual analogue scale, the short form of the Glasgow Composite Pain Scale, and mechanical nociceptive threshold (MNT) measurement at 0.5, 1, 2, 4, 6, 8, 12 and 20 hours after surgery by one blinded observer. Parametric data were tested using t-test; nonparametric data were analysed using the two-sample Wilcoxon test (p < 0.05). RESULTS: There was no significant difference between groups with regard to age, weight, surgical and anaesthetic duration, incision length, sedation and pain scores. MNT values decreased in both groups at all time points as compared with the baseline. No dog required rescue analgesia. No postoperative complications were observed. CONCLUSION AND CLINICAL RELEVANCE: Bupivacaine IP and carprofen SC after morphine IM did provide satisfactory postoperative analgesia in dogs undergoing OHE with the anaesthetic protocol used. There appears to be no clinical advantage to adding bupivacaine INC. Neither protocol could prevent the development of primary hyperalgesia.