Esmolol potentiates reduction of minimum alveolar isoflurane concentration by alfentanil

Effect of esmolol and lidocaine on agitation in awake phase of anesthesia among children: a double-blind, randomized clinical study

Background:

Sevoflurane is widely used to anesthetize children because of its rapid action with minimal irritation of the airways. However, there is a high risk of agitation after emergence from anesthesia. Strabismus surgery, in particular, can trigger agitation because patients have their eyes covered in the postoperative period. The aim of this study was to determine whether or not esmolol and lidocaine could decrease emergence agitation in children.

Methods:

Eighty-four patients aged 3 to 9 years undergoing strabismus surgery were randomly assigned to a control group (saline only), a group that received intravenous lidocaine 1.5 mg/kg, and a group that received intravenous esmolol 0.5 mg/kg and lidocaine 1.5 mg/kg. Agitation was measured using the objective pain score, Cole 5-point score, and Richmond Agitation Sedation Scale score at the end of surgery, on arrival in the recovery room, and 10 and 30 min after arrival.

Results:

The group that received the combination of esmolol and lidocaine showed lower OPS and RASS scores than the other two groups when patients awoke from anesthesia (OPS = 0 (0–4), RASS = –4 [(–5)–1]) and were transferred to the recovery room (OPS = 0 (0–8), RASS = –1 [(–5)–3]) (P < 0.05). There was no significant difference in the severity of agitation among the three groups at other time points (P > 0.05).

Conclusions:

When pediatric strabismus surgery is accompanied by sevoflurane anesthesia, an intravenous injection of esmolol and lidocaine could alleviate agitation until arrival in the recovery room.

Trial registration:

Clinical Research Information Service, No. KCT0002925; https://cris.nih.go.kr/cris/en/search/search_result_st01.jsp?seq=11532

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.

Comparative evaluation of the effect of remifentanil and 2 different doses of esmolol on pain during propofol injection: A double-blind, randomized clinical consort study

BACKGROUND

Propofol is associated with pain during injection, which is stressful to patients. The present study was designed to investigate the analgesic effect of pretreatment with remifentanil and esmolol in minimizing propofol injection pain, compared with placebo.

METHODS

In a randomized, double-blind, prospective trial, 120 patients, scheduled for elective dental surgery under general anesthesia, were randomized to 1 of the 4 treatment arms (n = 30 each) receiving normal saline, remifentanil 0.35 μg/kg, esmolol 0.5 mg/kg, and 1 mg/kg before administration of propofol. During injection of 1% propofol 0.5 mg/kg, pain was evaluated by a 4-point score (0 = none, 1 = mild, 2 = moderate, 3 = severe). Any adverse effects such as hypotension and bradycardia were recorded during the perioperative periods.

RESULTS

In all, 120 patients completed this study. There were no significant differences in terms of demographic data. The incidence of pain on injection of propofol was 11 (36.7%) with remifentanil 0.35 μg/kg, 12 (40%) with esmolol 0.5 mg/kg, and 11 (36.7%) with esmolol 1 mg/kg, compared with 25 (83.3%) with normal saline (respectively, P < 0.05). There were no significant differences in the incidence of pain between groups with remifentanil 0.35 μg/kg, and esmolol 0.5 mg/kg and 1 mg/kg. There were no emergence reactions such as hypotension and bradycardia in all groups.

CONCLUSIONS

Pretreatment with esmolol 0.5 mg/kg and 1 mg/kg and remifentanil 0.35 μg/kg equally decreased pain during propofol injection.

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.

Influence of esmolol on requirement of inhalational agent using entropy and assessment of its effect on immediate postoperative pain score

Background and Context:

Beta-blockers have been used for attenuation of stress response, decreasing anaesthetic requirement and augmentation of the effect of opioids during general anaesthesia.

Aims and Objectives:

The present study aims to evaluate the influence of esmolol on the requirement of an inhalational agent while monitoring the depth of anaesthesia by entropy and also its effect on immediate postoperative pain score.

Methods:

Fifty American Society of Anaesthesiologists (ASA) I and II patients, between 25 and 65 years of age who underwent lower abdominal surgeries were randomly allocated to two groups: Group E and Group S of 25 patients each. Group E received esmolol infusion while Group S received the same volume of saline infusion. Demographic data, haemodynamics, amount of isoflurane used, end-tidal isoflurane concentration, postoperative pain score and total dose of morphine consumed in immediate postoperative period of 30 min were analyzed by using appropriate statistical tests. Value of P<0.05 was considered significant and P<0.001 as highly significant.

Results:

The two groups were comparable with respect to age, weight, ASA physical status, duration of surgery and amount of isoflurane used during anaesthesia. Assessment of postoperative pain was assessed by Visual Analogue Scale (VAS) which showed significant difference at 30 min. The total dose of morphine consumption was significantly less (P<0.05) in Group E for relief of postoperative pain.

Conclusions:

We conclude that in light of depth of anaesthesia monitor esmolol has no effect on requirement of isoflurane, but it decreases the postoperative pain as well as postoperative requirement of morphine without increasing the risk of awareness.

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.

Morphine use in cancer surgery

Morphine is the core of perioperative pain management. However, when it comes to cancer surgery the possibility that this drug might affect tumor recurrence and metastasis has raised concerns. The results of two recent retrospective clinical trials indicated that regional anesthesia/analgesia might be beneficial in prostate and breast cancer surgery. It was proposed that morphine could be responsible for the higher recurrence and mortality rate observed in the general anesthesia/opioid analgesia groups. Nevertheless, the results of several other retrospective studies and one randomized prospective trial failed to confirm any advantage for regional anesthesia/analgesia over general anesthesia and opioid analgesia. Moreover laboratory data on the effect of morphine on cancer are contradictory, ranging from tumor-promoting to anti-tumor effects. Considering that surgical stress and pain promote the recurrence and spread of cancer, choosing a proper analgesic strategy is of high significance. Although the question of whether morphine causes any harm to cancer patients remains unanswered, alternative analgesic regimens could be used concomitant to or instead of morphine to limit its potential adverse effects.

β-Adrenergic Blockade Affects Initial Drug Distribution Due to Decreased Cardiac Output and Altered Blood Flow Distribution

Beta-adrenergic receptor blockers decrease intravenous anesthetic dose requirements. The present study determined the effect of propranolol on indocyanine green and antipyrine disposition from the moment of rapid intravenous injection. Anti-pyrine is a physiological marker that distributes to a volume as large as total body water in a blood flow-dependent manner and is a pharmacokinetic surrogate for many lipophilic drugs, including intravenous anesthetics. Antipyrine and indocyanine green disposition were determined twice in five healthy adult males in this Institutional Review Board-approved study, once during propranolol infusion. After rapid indocyanine green and antipyrine injection, arterial blood samples were collected frequently for 2 min and less frequently thereafter. Plasma indocyanine green and antipyrine concentrations were measured by high-performance liquid chromatography. Indocyanine green and antipyrine disposition were characterized, using SAAM II, by a recirculatory pharmacokinetic model that describes drug disposition from the moment of injection. Parameters were compared using the paired t test. The disposition of indocyanine green demonstrated that propranolol decreased cardiac output at the expense of the fast peripheral (nonsplanchnic) intravascular circuit. The area under the antipyrine concentration versus time relationship was doubled for at least the first 3 min after injection due to both decreased cardiac output and maintenance of nondistributive blood flow at the expense of a two-thirds reduction of blood flow (intercompartmental clearance) to the rapidly equilibrating (fast, splanchnic) tissue volume. The increase in antipyrine area under the curve due to propranolol-induced alteration of initial antipyrine disposition could explain decreased intravenous anesthetic dose requirements in the presence of beta-adrenergic receptor blockade.