Postoperative analgesia by intraarticular clonidine and neostigmine in patients undergoing knee arthroscopy

Sustained analgesic effect of clonidine co-polymer depot in a porcine incisional pain model

Background

Previous research suggests that the α₂ adrenergic agonist clonidine, a centrally acting analgesic and antihypertensive, may also have direct effects on peripheral pain generators. However, aqueous injections are limited by rapid systemic absorption leading to off target effects and a brief analgesic duration of action.

Purpose

The aim of this study was to examine the efficacy of a sustained-release clonidine depot, placed in the wound bed, in a pig incisional pain model.

Methods

The depot was a 15 mm ×5 mm ×0.3 mm poly(lactide-co-caprolactone) polymer film containing 3% (w/w) clonidine HCl (MDT3). Fifty-two young adult mix Landrace pigs (9–11 kg) were divided into seven groups. All subjects received a 6 cm, full-thickness, linear incision into the left lateral flank. Group 1 served as a Sham control group (Sham, n=8). Group 2 received three placebo strips (PBO, n=8), placed end-to-end in the subcutaneous wound bed before wound closure. Group 3 received one MDT3 and two PBO (n=8), Group 4 received two MDT3 and one PBO (n=8), and Group 5 received three MDT3 (n=8). Positive control groups received peri-incisional injections of bupivacaine solution (Group 6, 30 mg/day bupivacaine, n=8) or clonidine solution (Group 7, 225 µg/day, n=4).

Results

The surgical procedure was associated with significant peri-incisional tactile allodynia. There was a dose-dependent effect of MDT3 in partially reversing the peri-incisional tactile allodynia, with maximum pain relief relative to Sham at 72 hours. Daily injections of bupivacaine (30 mg), but not clonidine (up to 225 µg), completely reversed allodynia within 48 hours. There was a statistically significant correlation between the dose of MDT3 and cumulative withdrawal threshold from 4 hours through the conclusion of the study on day 7.

Conclusion

These data suggest that a sustained-release clonidine depot may be a viable nonopioid, nonamide anesthetic therapy for the treatment of acute postsurgical nociceptive sensitization.

Assessment of Intraoperative Intra-articular Morphine and Clonidine Injection in the Acute Postoperative Period After Hip Arthroscopy

BACKGROUND

Previous authors have suggested that intra-articular morphine and clonidine injections after knee arthroscopy have demonstrated equivocal analgesic effect in comparison with bupivacaine while circumventing the issue of chondrotoxicity. There have been no studies evaluating the effect of intra-articular morphine after hip arthroscopy.

PURPOSE

To evaluate the efficacy of intra-articular morphine in combination with clonidine on postoperative pain and narcotic consumption after hip arthroscopy surgery for femoroacetabular impingement.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

A retrospective chart review was performed on 43 patients that underwent hip arthroscopy for femoroacetabular impingement at a single institution between September 2014 and May 2015. All patients received preoperative celecoxib and acetaminophen, and 22 patients received an additional intra-articular injection of 10 mg morphine and 100 μg of clonidine at the conclusion of the procedure. Narcotic consumption, duration of anesthesia recovery, and perioperative pain scores were compared between the 2 groups.

RESULTS

Patients who received intra-articular morphine and clonidine used significantly less opioid analgesic (mEq) in the postanesthesia recovery (median difference, 17 mEq [95% CI, -32 to -2 mEq]; P = .02) compared with the control group. There were no differences in time spent in recovery before hospital discharge or in visual analog pain scores recorded immediately postoperatively and at 1 hour after surgery.

CONCLUSION

Intraoperative intra-articular injection of morphine and clonidine significantly reduced the narcotic requirement during the postsurgical recovery period after hip arthroscopy. The reduction in postsurgical opioids may decrease adverse effects, improve overall pain management, and lead to better quality of recovery and improved patient satisfaction.

Intra-articular clonidine for post-operative analgesia following arthroscopic knee surgery: a systematic review and meta-analysis

PURPOSE

To assess the efficacy and safety of a single dose of intra-articular clonidine for post-operative pain following arthroscopic knee surgery by analyzing relevant randomized controlled trials (RCTs).

METHODS

PubMed, EMBASE, Cochrane Library, ISI Web of knowledge, Chinese Biomedical Literature Database, Google Scholar and other databases were searched for RCTs comparing a single dose of intra-articular clonidine with placebo for post-operative pain following arthroscopic knee surgery. Risk of bias of included studies was assessed by Cochrane Collaboration's tool, and data were analyzed by RevMan 5.1 software. Pain intensity, supplementary analgesic use and side effects were evaluated as the outcomes.

RESULTS

Seven RCTs were included, and the results of the meta-analysis showed that intra-articular clonidine reduced the pain intensity for the first 4 h after surgery, reduced the risk of using rescue analgesics and the incidence of post-operative nausea, but increased the risk of hypotension after surgery.

CONCLUSIONS

A single dose of intra-articular clonidine has a definite analgesic effect, but the analgesic effect is mild and short lasting, which is just for 4 h after injection, and intra-articular clonidine alone could not provide sufficient post-operative analgesia following arthroscopic knee surgery. Post-operative hypotension may be the side effect that should be paid the most attention in the ambulatory setting.

LEVEL OF EVIDENCE

II.

Peripheral Suppression of Arthritic Pain by Intraarticular Fadolmidine, an α2-Adrenoceptor Agonist, in the Rat

BACKGROUND

Earlier results suggest that peripheral alpha(2)-adrenoceptors and opioid receptors may reduce arthritic pain. Fadolmidine is a highly selective alpha(2)-adrenoceptor agonist that has only limited central access after peripheral administration. We assessed the peripheral antinociceptive properties of fadolmidine and the potential contribution of peripheral opioid receptors to its antinociceptive effect in experimental monoarthritis.

METHODS

After induction of monoarthritis in the knee joints of rats, we determined the frequency of vocalization induced by repetitive movement of the knee joint. Fadolmidine and clonidine were administered intraarticularly ipsi- or contralateral to the inflamed joint. Reversal of the fadolmidine-induced effect was attempted with subcutaneous (s.c.) administration of atipamezole, an alpha(2)-adrenoceptor antagonist, and intraarticular administration of naloxone methiodide, an opioid receptor antagonist that does not penetrate the blood-brain barrier.

RESULTS

Fadolmidine produced a dose-dependent attenuation of the vocalization response to movement of the inflamed knee joint, and this effect was significantly stronger after ipsi- than contralateral drug administration. Clonidine also produced a dose-dependent attenuation of the vocalization response, but this effect was not significantly different after ipsi- versus contralateral drug administration. Fadolmidine-induced antinociception was reversed by s.c. administration of atipamezole. Furthermore, intraarticular administration of naloxone methiodide into the inflamed, but not the contralateral, joint reversed the antinociceptive effect of fadolmidine independent of whether fadolmidine was administered into the inflamed or contralateral joint.

CONCLUSIONS

In rats, intraarticular administration of fadolmidine provides a marked suppression of pain-related behavior in arthritis, due to a selective action on peripheral alpha(2)-adrenoceptors and opioid receptors.

Use of neostigmine in the management of acute postoperative pain and labour pain: a review

Neostigmine is a parasympathomimetic agent that has been recently investigated for use as an adjunct analgesic agent in the perioperative and peripartum period. A number of studies have investigated the intrathecal, epidural, caudal and intra-articular routes of administration of this agent, as well as the addition of neostigmine to local anaesthetics used for brachial plexus block and intravenous regional anaesthesia. While the intrathecal administration of neostigmine produced useful analgesic effects in the postoperative period in some studies, the high incidence of adverse events, mainly nausea and vomiting, limit the clinical usefulness of this route of administration. Several studies investigated the postoperative analgesic effects of epidural neostigmine using a number of different regimens. Overall, this route of administration appeared to improve postoperative analgesia in most studies without increasing the incidence of adverse events, and merits further research. Neuraxial administration of neostigmine appears to be safe in the obstetric population, with no reported adverse effects in the mother or fetus. While intrathecal administration is limited by a high incidence of nausea and vomiting in this patient population, the epidural route appears more promising and requires further investigation. The addition of neostigmine to caudal local anaesthetics was associated with improved postoperative analgesia in a number of studies. A dose of 2 microg/kg proved to be effective in several studies but was associated with an increased incidence of vomiting in some studies. Intra-articular administration of neostigmine 500microg produced a useful analgesic effect in the postoperative period in several studies and was not associated with an increase in the incidence of adverse effects. Studies investigating the efficacy of adding neostigmine to the local anaesthetics used for brachial plexus block and intravenous regional anaesthesia reported conflicting results. Further studies are required to determine the place of the administration of neostigmine by these routes.

Transcutaneous electrical nerve stimulation activates peripherally located alpha-2A adrenergic receptors

The alpha2A and alpha2C adrenergic receptor (AR) subtypes mediate antinociception when activated by the endogenous ligand norepinephrine. These receptors also produce antinociceptive synergy when activated concurrently with opioid receptor activation. The involvement of the opioid receptors in the mechanisms governing transcutaneous electrical nerve stimulation (TENS) has been well described. While spinal alpha-2 ARs do not appear to be involved in TENS antihyperalgesia in rats, the noradrenergic analgesic system also involves supraspinal and peripheral sites. Thus, a broader evaluation of the potential contribution of alpha-2 AR to TENS is warranted. The current study compared the antihyperalgesic efficacy of high (100 Hz) and low (4 Hz) frequency TENS in mutant mice lacking a functional alpha2A AR against their respective wildtype counterparts. The degree of secondary heat hyperalgesia induced by intra-articular injection of carrageenan/kaolin (3%) mixture did not differ among the experimental groups. However, the antihyperalgesia induced by both low and high frequency TENS was significantly diminished in alpha2A mutant mice compared to controls. The alpha2 adrenergic receptor selective antagonist, SK&F 86466, reversed TENS-mediated antihyperalgesia when delivered intra-articularly, but not when delivered intrathecally or intracerebroventricularly. These data suggest that peripheral alpha2 ARs contribute, in part, to TENS antihyperalgesia. This pharmacodynamic response is consistent with previous anatomical observations that alpha2A ARs are expressed on primary afferent neurons and macrophages near injured tissue.