Are beta-blockers anesthestics?

Intra-operative esmolol and pain following mastectomy: A randomised clinical trial

BACKGROUND

Esmolol is a beta-1 selective blocker that has been shown to reduce postoperative pain. Its antinociceptive effects have not been tested following mastectomy.

OBJECTIVE

To evaluate the safety, efficacy and antinociception of intra-operative esmolol infusion after mastectomy.

DESIGN

Randomised, double-blinded, placebo-controlled trial.

SETTING

Tertiary referral centre, Brasília, Brazil. Recruitment: July 2015 to July 2017.

PATIENTS

Seventy women scheduled for mastectomy, ASA I to III, aged 18 to 75 years. Four were excluded.

INTERVENTIONS

All underwent general anaesthesia. The intervention group received a bolus of 0.5 mg kg-1 of esmolol over 10 min followed by a continuous infusion of 100 μg kg-1 min-1. The placebo group received saline.

MAIN OUTCOME MEASURES

The primary outcome was pain at rest 24 h after mastectomy as measured by a 0 to 10 numeric rating scale.

RESULTS

Pain scores at rest 24 h after mastectomy were lower in esmolol-treated patients compared with placebo (mean difference = -1.51, 95% confidence interval (CI), -2.36 to -0.65, P = 0.001). On arrival in the postanaesthesia care unit (PACU), the occurrence of pain was also lower in the esmolol group, at rest and on effort (P = 0.009 and P = 0.013, respectively), on discharge from PACU (P = 0.009 and P = 0.015), 12 h (P = 0.01 and P = 0.007) and on effort in the 24 postoperative hours (P = 0.003). Mean morphine consumption was reduced by 77% in the esmolol group compared with the placebo group (mean difference  = -2.52 mg, 95% CI = -3.67 to -1.38, P < 0.001). The length of hospital stay was shorter for the esmolol group (mean difference = -6.9 h, 95% CI, -13.4 to -0.31, P = 0.040).

CONCLUSION

Esmolol was well tolerated, allowed a notable reduction in the dose of rescue analgesics and demonstrated superior efficacy compared to placebo for pain management after mastectomy.

TRIAL REGISTRATION

ClinicalTrials/NCT02466542.

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.

Esmolol reduces anesthetic requirements thereby facilitating early extubation; a prospective controlled study in patients undergoing intracranial surgery

BACKGROUND

Adequate cerebral perfusion pressure with quick and smooth emergence from anesthesia is a major concern of the neuroanesthesiologist. Anesthesia techniques that minimize anesthetic requirements and their effects may be beneficial. Esmolol, a short acting hyperselective β-adrenergic blocker is effective in blunting adrenergic response to several perioperative stimuli and so it might interfere in the effect of the anesthetic drugs on the brain. This study was designed to investigate the effect of esmolol on the consumption of propofol and sevoflurane in patients undergoing craniotomy.

METHOD

Forty-two patients that underwent craniotomy for aneurysm clipping or tumour dissection were randomly divided in two groups (four subgroups). Anesthesia was induced with propofol, fentanyl and a single dose of cis-atracurium, followed by continuous infusion of remifentanil and either propofol or sevoflurane. Patients in the esmolol group received 500 mcg/kg of esmolol bolus 10 min before induction of anesthesia, followed by additional 200 mcg/kg/min of esmolol. Monitoring of the depth of anesthesia was also performed using the Bispectral Index-BIS and cardiac output. The inspired concentration of sevoflurane and the infusion rate of propofol were adjusted in order to maintain a BIS value between 40-50. Intraoperative emergence was detected by the elevation of BIS value, HR or MAP.

RESULTS

The initial and the intraoperative doses of propofol and sevoflurane were 18-50 mcg/kg/min and 0.2-0.5 MAC respectively in the esmolol group, whereas in the control group they where 100-150 mcg/kg/ and 0.9-2.0 MAC respectively (p = 0.000 for both groups). All procedures were anesthesiologically uneventful with no episodes of intraoperative emerge.

CONCLUSIONS

Esmolol is effective not only in attenuating intraoperative hemodynamic changes related to sympathetic overdrive but also in minimizing significant propofol and sevoflurane requirements without compromising the hemodynamic status. ClinicalTrials.gov Identifier: NCT02455440 . Registered 26 May 2015.

Effect of intravenous esmolol on analgesic requirements in laparoscopic cholecystectomy

Background and Aims:

Perioperative beta blockers are also being advocated for modulation of acute pain and reduction of intraoperative anesthetic requirements. This study evaluated the effect of perioperative use of esmolol, an ultra short acting beta blocker, on anesthesia and modulation of post operative pain in patients of laproscopic cholecystectomy.

Material and Methods:

Sixty adult ASA I & II grade patients of either sex, scheduled for laparoscopic cholecystectomy under general anesthesia, were enrolled in the study. The patients were randomly allocated to one of the two groups E or C according to computer generated numbers. Group E- Patients who received loading dose of injection esmolol 0.5 mg/kg in 30 ml isotonic saline, before induction of anesthesia, followed by an IV infusion of esmolol 0.05 μg/kg/min till the completion of surgery and Group C- Patients who received 30 ml of isotonic saline as loading dose and continuous infusion of isotonic saline at the same rate as the esmolol group till the completion of surgery.

Results:

The baseline MAP at 0 minute was almost similar in both the groups. At 8th minute (time of intubation), MAP increased significantly in group C as compared to group E and remained higher than group E till the end of procedure. Intraoperatively, 16.67% of patients in group C showed somatic signs as compared to none in group E. The difference was statistically significant. 73.33% of patients in group C required additional doses of Inj. Fentanyl as compared to 6.67% in group E.

Conclusions:

We conclude that intravenous esmolol influences the analgesic requirements both intraoperatively as well as postoperatively by modulation of the sympathetic component of the pain i.e. heart rate and blood pressure.

Effect of Intravenous Intraoperative Esmolol on Pain Management Following Lower Limb Orthopedic Surgery

BACKGROUND

Lack of proper control of acute postoperative pain often leads to lingering or chronic pain. Several studies have emphasized the role of beta-blockers in reducing postoperative pain. Esmolol is a selective short-acting beta-blocker that produces few side effects. The purpose of this study was to examine the effect of intravenous intraoperative esmolol on postoperative pain reduction following orthopedic leg fracture surgery.

METHODS

In a clinical trial, 82 patients between 20-65 years of age with tibia fractures and American Society of Anesthesiologists (ASA) physical status I & II who underwent surgery were divided into two groups. Group A received esmolol and group B received normal saline. Postoperative pain was measured at three time points: entering the recovery unit, and at 3 h and 6 h following surgery, using the Visual Analogue Scale (VAS). A P value of < 0.05 was considered significant.

RESULTS

Mean VAS scores at all three time points were significantly different between the two test groups (P = 0.02, P = 0.0001, and P = 0.0001, respectively). The consumption of pethidine was lower in group A than in group B (P = 0.004) and the duration of its effect was significantly longer in time (P = 0.026).

CONCLUSIONS

Intravenous intraoperative esmolol is effective in the reduction of postoperative pain following leg fracture surgery. It reduced opioid consumption following surgery and delayed patient requests for analgesics.

Comparison of effects of intraoperative esmolol and ketamine infusion on acute postoperative pain after remifentanil-based anesthesia in patients undergoing laparoscopic cholecystectomy

BACKGROUND

Remifentanil is a short-acting drug with a rapid onset that is useful in general anesthesia. Recently, however, it has been suggested that the use of opioids during surgery may cause opioid-induced hyperalgesia (OIH). Researchers have recently reported that esmolol, an ultra-short-acing β1 receptor antagonist, reduces the postoperative requirement for morphine and provides more effective analgesia than the administration of remifentanil and ketamine. Hence, this study was conducted to determine whether esmolol reduces early postoperative pain in patients who are continuously infused with remifentanil for anesthesia during laparoscopic cholecystectomy.

METHODS

Sixty patients scheduled to undergo laparoscopic cholecystectomy were randomly divided into three groups. Anesthesia was maintained with sevoflurane and 4 ng/ml (target-controlled infusion) of remifentanil in all patients. Esmolol (0.5 mg/kg) was injected and followed with a continuous dosage of 10 µg/kg/min in the esmolol group (n = 20). Ketamine (0.3 mg/kg) was injected and followed with a continuous dosage of 3 µg/kg/min in the ketamine group (n = 20), while the control group was injected and infused with an equal amount of normal saline. Postoperative pain score (visual analog scale [VAS]) and analgesic requirements were compared for the first 6 hours of the postoperative period.

RESULTS

The pain score (VAS) and fentanyl requirement for 15 minutes after surgery were lower in the esmolol and ketamine groups compared with the control group (P < 0.05). There were no differences between the esmolol and ketamine groups.

CONCLUSIONS

Intraoperative esmolol infusion during laparoscopic cholecystectomy reduced opioid requirement and pain score (VAS) during the early postoperative period after remifentanil-based anesthesia.

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 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.

Intravenous landiolol, a novel β(1)-adrenergic blocker, reduces the minimum alveolar concentration of sevoflurane in women

STUDY OBJECTIVE

To investigate the effect of intravenous (IV) landiolol, a novel β(1)-adrenergic blocker, on the minimum alveolar concentration (MAC) of sevoflurane in adult women.

DESIGN

Prospective, randomized study.

SETTING

University hospital.

PATIENTS

42 ASA physical status 1 and 2 women, aged 24-57 years, who were scheduled to undergo elective abdominal surgery.

INTERVENTIONS

Anesthesia was induced in all patients by vital capacity rapid inhalation induction of sevoflurane. In the landiolol group, administration of landiolol began when patients took a vital-capacity breath: 0.125 mg/kg/min for one minute and then 0.04 mg/kg/min. Normal saline was administered in the control group.

MEASUREMENTS

MAC was determined by a technique adapted from the conventional up-down method.

MAIN RESULTS

The MAC of sevoflurane was 2.2% ± 0.2% in the control group and 1.7% ± 0.2% in the landiolol group, a statistically significant difference (P = 0.0005).

CONCLUSIONS

IV landiolol reduces the MAC of sevoflurane in women by approximately 20%.