Analgesic effects of intraorbital insertion of an absorbable gelatin hemostatic sponge soaked with 1% ropivacaine solution following enucleation in dogs

Clinical Application of Different Doses of Hydromorphone Slow-Release Analgesia in Lumbar Fusion in Elderly Patients

INTRODUCTION

The aim of this study is to examine the analgesic efficacy of varying doses of hydromorphone hydrochloride in conjunction with absorbable gelatin sponge for postoperative pain management in elderly individuals undergoing lumbar fusion surgery. Additionally, the study aims to assess the sustained release analgesic properties of this combination and to determine the optimal dosage of hydromorphone hydrochloride for effective pain relief.

METHODS

A total of 113 elderly patients (aged ≥ 65 years old) meeting the criteria for 1-2-level posterior lumbar fusion surgery at Ganzhou City People's Hospital between July 2022 and August 2023 were randomly assigned to four groups: group A (0.2 mg hydromorphone hydrochloride 1 ml), group B (0.3 mg hydromorphone hydrochloride 1.5 ml), group C (0.4 mg hydromorphone hydrochloride 2 ml), and group D (0.9% normal saline 2 ml) for standard anesthesia induction and maintenance. Prior to suturing the incision, gelfoam was utilized to administer epidural analgesia to each group. Following the surgical procedure, an intravenous analgesia pump was utilized for pain management. The baseline infusion rate was set at 0.5 ml/h. Patient-controlled analgesia (PCA) was administered at a dose of 2 ml, with a lockout interval of 20 min, allowing the patient to self-administer as needed. Pain relief was assessed using the visual analogue scale (VAS) prior to surgery, as well as at 1 day and 3 days post-operation. The frequency of PCA requests within the initial 48-h postoperative period, the remedial analgesia with dezocine, postoperative adverse reactions, and duration of hospitalization were documented for analysis.

RESULTS

The VAS scores of groups B and C were found to be significantly lower than those of group D 1 day after the operation. Additionally, VAS scores at 3 days post-operation, remedial rate of dezocine and PCA follow-up times at 48 h in groups A, B, and C were significantly lower compared to group D (P < 0.001). There was no statistically significant difference between group B and group C in VAS scores at 1 day and 3 days post-operation, as well as PCA follow-up times at 48 h post-operation (P < 0.001). Furthermore, the VAS scores of groups B and C were lower than those of group A at 1 day and 3 days post-operation (P < 0.05). The PCA frequency of group C was also lower than that of group A at 48 h post-operation (P < 0.05).

CONCLUSION

The combination of hydromorphone hydrochloride and absorbable gelatin sponge epidural analgesia has been shown to enhance postoperative pain management. A dosage of 0.4 mg of hydromorphone hydrochloride may be considered an appropriate analgesic dose, as it can provide effective pain relief without eliciting adverse reactions.

TRIAL REGISTRATION

ChiCTR.org.cn(ChiCTR2200064863). Registered on October 20, 2022.

Analgesic effects of a retrobulbar block with 0.75% ropivacaine in dogs undergoing enucleation

OBJECTIVE

To assess the analgesic effects of a retrobulbar block with ropivacaine in dogs undergoing enucleation.

STUDY DESIGN

Prospective, randomized, masked placebo-controlled trial.

ANIMALS

A total of 23 client-owned dogs.

METHODS

Dogs were randomized to be administered a preoperative inferior-temporal palpebral retrobulbar injection of either ropivacaine 0.75% (1 mL 10 kg^-1; group RG) or equivalent volume of 0.9% saline (control; group CG). Intraoperative variables recorded to detect a response to noxious stimuli included heart rate (HR) and mean arterial pressure (MAP). Three observers assessed and recorded pain using a numerical rating pain scale and visual analog scale (VAS) before anesthesia (baseline) and postoperatively at 0, 0.5, 1, 2, 3, 4, 5, 6 and 24 hours after extubation. Rescue analgesia was administered if intraoperative HR or MAP increased by ≥ 20% from the previously recorded surgical time point, average postoperative pain scores totaled ≥ 9/20, scored ≥ 3/4 in any one category with VAS ≥ 35/100, or if VAS was ≥ 35/100 with a palpation score > 0/4.

RESULTS

Intraoperatively, there was no significant difference in HR or MAP between groups. Rescue analgesia was administered intraoperatively to four and one dogs and postoperatively to five and seven dogs in groups CG and RG, respectively, with no significant difference between groups. VAS scores were significantly lower in ropivacaine dogs at extubation (p = 0.02), but not at other postoperative time points. Adverse events were not observed in either group.

CONCLUSIONS AND CLINICAL RELEVANCE

Preoperative retrobulbar 0.75% ropivacaine injection (1 mL 10 kg^-1) provided analgesia in dogs following enucleation at extubation; however, intraoperative and postoperative pain control did not differ from a placebo injection with saline. Lack of differences between groups may have been influenced by sample size limitations.