Possible indications of beta-blockers in the perioperative period other than prevention of cardiac ischemia

Do β-adrenoreceptor blocking drugs associate with reduced risk of symptomatic osteoarthritis and total joint replacement in the general population? A primary care-based, prospective cohort study using the Clinical Practice Research Datalink

INTRODUCTION

To investigate if β-adrenoreceptor blocking drug (β-blocker) prescription reduces the risk of knee or hip osteoarthritis, total joint replacement and analgesic prescription.

SETTING

Primary care.

METHODS AND ANALYSIS

This is a cohort study using data from the Clinical Practice Research Datalink. Two separate analyses will be performed. Study 1 will be on the association between β-blocker prescription and incident knee/hip osteoarthritis. Inclusion criteria will be age ≥40 years. Exposed participants will be those with ≥2 continuous β-blocker prescriptions, and the index date will be the date of the first prescription of β-blocker. Unexposed participants will include up to four controls matched for age, sex, general practice surgery and propensity score for β-blocker prescription. Exclusion criteria will include contraindications to β-blockers, consultations for osteoarthritis or potent analgesic prescription before the index date. Outcomes will be knee osteoarthritis (primary outcome), hip osteoarthritis, knee pain and hip pain. Study 2 will be on the association between β-blocker prescription and total joint replacement and analgesic prescription in people with osteoarthritis. Inclusion criteria will be age ≥40 years, knee or hip osteoarthritis, and index date will be as in study 1. Unexposed participants will be as in study 1, additionally matched for consultation for knee or hip osteoarthritis prior to the index date. Exclusion criteria will include contraindications to β-blockers and osteoarthritis in other joints prior to the index date. Outcomes will be total knee replacement (primary outcome), total hip replacement and new analgesic prescription.

STATISTICAL ANALYSIS

Kaplan-Meier curves will be plotted, and Cox proportional HRs and 95% CIs will be calculated. Stratified analysis will be performed by class of β-blocker, intrinsic sympathomimetic effect and indication(s) for prescription.

ETHICS AND DISSEMINATION

This study was ethically approved by the Independent Scientific Advisory Committee of the Medicines and Healthcare Authority (Ref 18_227R). The results of this study will be published in peer-reviewed journals and presented at conferences.

SUMMARY

This prospective cohort study will evaluate the analgesic potential of commonly used drugs for osteoarthritis pain.

Neuroprotection against stroke and encephalopathy after cardiac surgery

Cerebral ischemia in the perioperative period is a major risk factor for stroke, encephalopathy, and cognitive decline after cardiothoracic surgery. After coronary artery bypass grafting, both stroke and encephalopathy can result in poor patient outcomes and increased mortality. Neuroprotection aims to lessen the severity and occurrence of further injury mediated by stroke and encephalopathy and to aid the recovery of conditions already present. Several pharmacological and non-pharmacological methods of neuroprotection have been investigated in experimental studies and in animal models, and, although some have shown effectiveness in protection of the central nervous system, for most, clinical research is lacking or did not show the expected results. This review summarizes the value and need for neuroprotection in the context of cardiothoracic surgery and examines the use and effectiveness of several agents and methods with an emphasis on clinical trials and clinically relevant neuroprotectants.

The effect of esmolol compared to opioids on postoperative nausea and vomiting, postanesthesia care unit discharge time, and analgesia in noncardiac surgery: A meta-analysis

Background and Aims:

Perioperative esmolol as an opioid alternative has been shown to reduce postoperative nausea vomiting using opioid sparing. The aim of this meta-analysis was to compare esmolol and opioids on postoperative nausea and vomiting (PONV), time spent in recovery, and analgesia in noncardiac surgeries.

Material and Methods:

OVID Medline (1980–February 2014), OVID EMBASE, EBSCO, CINAHL, and the Cochrane Register of Controlled Trials were searched for randomized controlled trials (RCTs) comparing esmolol and opioids on early postoperative recovery and pain intensity during general anesthesia in noncardiac surgeries. The primary outcomes were related to PONV and postanesthesia care unit (PACU) discharge time, whereas secondary outcomes were related to early postoperative pain.

Results:

Eight trials were identified involving 439 patients, 228 of whom received esmolol while 211 received opioids. A random-effects meta-analysis showed that in comparison with opioids, esmolol led to a 69% reduction in the incidence of PONV (odds ratio 0.31, 95% confidence interval [CI] 0.13–0.74, P = 0.008, I² = 44.1%). An increase in the volatile anesthetic requirement was evident in the esmolol group compared with opioid (MD + 0.67% desflurane equivalent, 95% CI 0.27–1.08, P = 0.001, I² =23.5%). There was no statistically significant difference between the esmolol and opioid groups in relation to PACU discharge time, early postoperative pain scores, opioid requirement, and cumulative opioid consumption. Significant heterogeneity was noted between studies. No significant adverse effects were noted.

Conclusion:

Compared with opioids, perioperative esmolol may reduce the incidence of postoperative nausea vomiting and increase the volatile anesthetic requirement. Esmolol administration may not improve the early postoperaive pain intensity. Nonetheless, these findings are limited by the absence of high-quality RCTs and the heterogeneity among studies. Further, large-scale studies are needed to explore these results.

The effect of perioperative esmolol on early postoperative pain: A systematic review and meta-analysis

Esmolol has been shown to improve postoperative pain and reduce opioid requirements. The aim of this systematic review was to evaluate the effect of perioperative esmolol as an adjunct on early postoperative pain intensity, recovery profile, and anesthetic requirement. Databases were searched for randomized placebo-controlled trials evaluating the effects of esmolol during general anesthesia. Primary outcomes were related to early postoperative pain whereas secondary outcomes were related to emergence time, postoperative nausea and vomiting, and intraoperative anesthetic requirement. Nineteen trials were identified involving 936 patients (esmolol = 470, placebo = 466). In esmolol group, numeric pain scores at rest in the immediate postoperative period were reduced by 1.16 (95% confidence interval [CI]: 1.97–0.35, I² = 96.7%) out of 10. Opioid consumption was also decreased in the postanesthesia care unit compared with placebo, mean difference of 5.1 mg (95% CI: 7.0–3.2, I² = 96.9%) morphine IV equivalents; a 69% reduction in opioid rescue dosing was noted (odds ratio [OR]: 0.31, 95% CI: 0.16–0.80, I² = 0.0%). A 61% reduction in postoperative nausea and vomiting was also evident (OR: 0.39, 95% CI: 0.20–0.75, I² = 60.7%). A reduction in propofol induction dose was noted in the esmolol group (mean difference: −0.53 mg/kg, 95% CI: −0.63–−0.44, I² = 0.0%). A decrease in end-tidal desflurane equivalent (mean difference: 1.70%, 95% CI: −2.39–−1.02, I² = 92.0%) and intraoperative opioid usage (fentanyl equivalent, mean difference: 440 μg, 95% CI: −637–−244, I² = 99.6%) was observed in esmolol group. Esmolol had no effect on the emergence time. Perioperative esmolol as an adjunct may reduce postoperative pain intensity, opioid consumption, and postoperative nausea vomiting. Given the heterogeneity, larger clinical trials are warranted to confirm these findings.

Propranolol Attenuates Surgical Stress-Induced Elevation of the Regulatory T Cell Response in Patients Undergoing Radical Mastectomy

Surgical stress and inflammatory response induce the release of catecholamines and PGs, which may be key factors in facilitating cancer recurrence through immunosuppression. Animal studies have suggested the efficacy of perioperative blockades of catecholamines and PGs in reducing immunosuppression. In this study, to our knowledge, we present the first report of the effects of perioperative propranolol and/or parecoxib on peripheral regulatory T cells (Tregs) in breast cancer patients. Patients were randomly assigned to control, propranolol, parecoxib, and propranolol plus parecoxib groups. We demonstrated that levels of circulating epinephrine, norepinephrine, and PGE2increased in response to surgery. Meanwhile, peripheral FOXP3 mRNA level and Treg frequencies were elevated on postoperative day 7. Propranolol administration, rather than parecoxib, attenuated such elevation of Tregs, indicating the critical roles for catecholamines in surgery-induced promotion of Tregs. Besides, propranolol plus parecoxib treatment demonstrated no additive or synergistic effects. Furthermore, a study of Treg activity on CD4(+)T cell responses to specific tumor Ags was performed in the control and propranolol groups. Propranolol abrogated the increased Treg activity and accompanying suppression of CD4(+)T cell responses after surgery. Finally, we conducted ex vivo experiments on the effects of varying concentrations of epinephrine and/or propranolol on Treg proliferation over PBMCs from breast cancer patients, to provide further direct evidence strengthening our clinical observations. Epinephrine markedly promoted Treg proliferation, whereas propranolol prevented such enhancement effect. In conclusion, our study highlights beneficial roles for propranolol in inhibiting Treg responses in vivo and in vitro, and demonstrates that propranolol could alleviate surgical stress-induced elevation of Tregs in breast cancer patients.

Esmolol versus ketamine-remifentanil combination for early postoperative analgesia after laparoscopic cholecystectomy: a randomized controlled trial

PURPOSE

Controversy surrounds the optimal technique to moderate pain after laparoscopic cholecystectomy (LC). Opioid analgesics, sympatholytic drugs, and adjuvants, such as ketamine, have all been used. We compared esmolol with a combination of remifentanil plus ketamine in patients undergoing LC to determine the impact of these drugs on morphine requirements and pain control.

METHODS

Sixty American Society of Anesthesiologists physical status I-II patients undergoing LC and anesthetized with sevoflurane were randomized to one of two groups. Group E patients received a bolus of esmolol 0.5 mg·kg(-1) iv at induction followed by an infusion of 5-15 μg·kg(-1)·min(-1), and Group R-K patients received a bolus of ketamine 0.5 mg·kg(-1) iv and remifentanil 0.5 μg·kg(-1) iv at induction followed by a remifentanil infusion titrated over a range of 0.1-0.5 μg·kg(-1)·min(-1). All patients received paracetamol, dexketoprofen, and levobupivacaine via infiltration of laparoscopic port sites. After surgery, a predetermined bolus of morphine was administered according to a verbal numerical rating scale (VNRS) for pain intensity. The primary outcome of interest was postoperative morphine requirement.

RESULTS

Median consumption of morphine was higher in Group R-K than in Group E (5 mg [4-6] vs 0 mg [0-2], respectively; P < 0.001). In the postanesthesia care unit, patients in Group R-K had higher pain scores than patients in Group E (difference in maximum VNRS, -11; 95% confidence interval (CI), -19 to -3). The concentration of sevoflurane to maintain a bispectral index~40 was higher in Group E than in Group R-K (between-group difference 0.3%; 95% CI, 0.15 to 0.40). The incidence of postoperative nausea and vomiting was similar between the two groups.

CONCLUSION

Intraoperative esmolol infusion reduces morphine requirements and provides more effective analgesia compared with a combination of remifentanil-ketamine given by infusion in patients undergoing LC.

Esmolol modulates inhibitory neurotransmission in the substantia gelatinosa of the spinal trigeminal nucleus of the rat

Background

β₁-adrenaline receptor antagonists are often used to avoid circulatory complications during anesthesia in patients with cardiovascular diseases. Of these drugs, esmolol, a short-acting β antagonist, is also reported to exert antinociceptive and anesthetic sparing effects. This study was designed to identify the central mechanism underlying the antinociceptive effect of esmolol.

Methods

Wistar rats (7-21 d, 17-50 g) were anesthetized with ketamine (100-150 mg/kg) or isoflurane (5%) and decapitated. Horizontal slices (400-μm thick) of the lower brainstem containing the substantia gelatinosa (SG) of the caudal part of the spinal trigeminal nucleus (Sp5c), in which the nociceptive primary afferents form the first intracranial synapses, were made with a vibrating slicer. The miniature inhibitory and excitatory postsynaptic currents (mIPSCs and mEPSCs, respectively) were simultaneously recorded from visually identified SG neurons of the Sp5c in the presence of tetrodotoxin (1 μM). Additionally, mIPSCs were recorded during pharmacological isolation of GABA- and glycine-mediated mIPSCs with kynurenic acid (1 mM).

Results

Esmolol (500 μM) significantly and selectively increased the mIPSC frequency (to 214.2% ± 34.2% of the control, mean ± SEM, n = 35; P < 0.001), but not that of mEPSCs, without changing their amplitude. The increase in mIPSC frequency with esmolol was not affected by prior activation of β receptors with isoproterenol (100 μM) but it was significantly attenuated by removal of extracellular Ca²⁺.

Conclusions

These data suggest that esmolol modulates inhibitory transmitter release in the Sp5c through a mechanism involving Ca²⁺-entry but in a β₁-adrenoceptor-independent manner. The present results suggest that the facilitation of inhibitory transmitter release in the central nociceptive network underlies, at least in part, the antinociceptive effect of esmolol.

Cardioprotective effects of perioperative β-blockade in vascular surgery patients: fact or fiction?

PURPOSE OF REVIEW

Perioperative β-blockade remains a subject of debate. In this review, recent literature and current guidelines for perioperative β-blockade in vascular surgery patients are discussed.

RECENT FINDINGS

Available evidence suggests that perioperative β-blockade may be beneficial in reducing cardiac events. However, in a recent large study, the incidences of stroke and mortality were increased in patients on perioperative β-blockers. Large systematic reviews failed to demonstrate a net beneficial effect of perioperative β-blockers. The 2009 American and the European guidelines for perioperative β-blockade in vascular surgery disagree on the available evidence but do recommend β-blockade for several indications. Most recent, Wallace and colleagues published a large-sized retrospective study, reporting a beneficial effect of the adoption of a protocol for perioperative β-blockade.

SUMMARY

Perioperative β-blockade reduces cardiac events, but at the expense of increased risk for mortality and stroke. The guidelines seem to be eager to follow positive outcome studies, without considering the effects of β-blockade on other organ systems. Perhaps the main reason for the reported cardioprotective effects of perioperative β-blocker therapy should be sought in failing preoperative β-blocker prophylaxis (irrespective of surgery).