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

A Comparative Study of the Effect of Labetalol and Remifentanil on Pain Control After Bariatric Surgery

Background

Finding the optimal combination of anesthetics to maintain hemodynamic stability during surgery can be challenging. Traditionally, strong opioid analgesics such as fentanyl and its newer analogs have been used. However, the use of narcotics is associated with certain side effects.

Objectives

This study compares the effects of labetalol and remifentanil in pain control after bariatric surgery in Hazrat Rasool Akram Hospital.

Methods

This randomized, double-blind clinical trial was conducted on 48 laparoscopic bariatric surgery patients. The participants were randomly divided into two groups receiving remifentanil or labetalol. Postoperative pain was measured in the recovery unit using the numerical rating scale (NRS). This score was recorded upon entering recovery, and 30 minutes, 60 minutes, and 120 minutes after surgery for each patient. Also, the duration of anesthesia, the duration of the operation, the recovery time, the dose of the administered opioids, the volume of intravenous fluids, and the dose of administered propofol were recorded for each patient. Nausea and vomiting after the operation were also recorded as outcomes.

Results

There were no significant differences between the two groups regarding the mean duration of surgery and anesthesia, dose of the administered anesthetics, recovery period, nausea and vomiting, and the dose of analgesics after the operation. The mean pain intensity during the given period and also the trend of pain intensity changes between the two groups demonstrated no statistically significant differences (P = 0.112). During the operation, 9 subjects (37.5%) in the labetalol group and 16 (66.7%) in the remifentanil group needed more analgesics (rescue drug); in this regard, a significant difference was observed between the two groups (P = 0.043).

Conclusions

Based on the study's findings, there were no significant differences between labetalol and remifentanil in post and perioperative pain control. However, rescue drugs needed to maintain hemodynamic stability during laparoscopic surgery were significantly lower in patients who received labetalol than remifentanil. Postoperative complications were also comparable between labetalol and remifentanil.

The future of cancer nursing in Europe: Addressing professional issues in education, research, policy and practice

Cancer nursing has evolved to meet the demands of rising cancer incidence, newer and more complex treatment options, and the emergence of specialist roles supporting patients from pre-diagnosis, through treatment, survivorship and end of life care. Nurses are involved in direct and in-direct care of people at risk of, and living with and after cancer in diverse contexts. As a result, nurses are positioned to have a significant influence on the processes and outcomes of cancer care, through education, research, policy, practice and leadership. However, nursing and cancer care face challenges, arising from workforce shortages, under-investment in services and under-representation in decision-making. This paper discusses the evolution of cancer nursing across education, policy, research, profession and practice, and sets an agenda for innovation and disruption across these domains to ensure sustainability of cancer care services and care for people living with and after cancer. We argue for the continued advancement of cancer nursing with critical focus on identifying and addressing inequities in role recognition and access to specialist cancer nursing education throughout Europe. Partnership, exchange of learning, and co-design will be central to progressing education, evidence and policy to support future growth in the cancer nursing workforce and embed cancer nurses in research and policy setting at local, national and international levels.

Knowing the Enemy Is Halfway towards Victory: A Scoping Review on Opioid-Induced Hyperalgesia

Opioid-induced hyperalgesia (OIH) is a paradoxical effect of opioids that is not consensually recognized in clinical settings. We conducted a revision of clinical and preclinical studies and discuss them side by side to provide an updated and renewed view on OIH. We critically analyze data on the human manifestations of OIH in the context of chronic and post-operative pain. We also discuss how, in the context of cancer pain, though there are no direct evidence of OIH, several inherent conditions to the tumor and chemotherapy provide a substrate for the development of OIH. The review of the clinical data, namely in what concerns the strategies to counter OIH, emphasizes how much OIH rely mechanistically on the existence of µ-opioid receptor (MOR) signaling through opposite, inhibitory/antinociceptive and excitatory/pronociceptive, pathways. The rationale for the maladaptive excitatory signaling of opioids is provided by the emerging growing information on the functional role of alternative splicing and heteromerization of MOR. The crossroads between opioids and neuroinflammation also play a major role in OIH. The latest pre-clinical data in this field brings new insights to new and promising therapeutic targets to address OIH. In conclusion, although OIH remains insufficiently recognized in clinical practice, the appropriate diagnosis can turn it into a treatable pain disorder. Therefore, in times of scarce alternatives to opioids to treat pain, mainly unmanageable chronic pain, increased knowledge and recognition of OIH, likely represent the first steps towards safer and efficient use of opioids as analgesics.

Use of an ultrashort-acting selective β1-adrenergic receptor antagonist esmolol in ear, nose and throat surgery

Background / Aim: The concept of general balanced anaesthesia was devised in order to assure cardiovascular stability and fast post-anaesthesia recovery. This clinical trial was organised in order to investigate the parameters of cardiovascular function and emergence from anaesthesia in elective ear, nose and throat (ENT) surgery patients. Methods: A total of 40 ASA I and II patients of both sexes scheduled for elective ENT surgery were randomly divided into two equal groups. Both groups received a continuous IV infusion of glucose 5 % solution and in the esmolol group this infusion also contained esmolol. Esmolol infusion rate was 0.3 mg/kg/min during the first 5 min and thereafter 0.1 mg/kg/min. In critical phases of anaesthesia and operation (induction, intubation, first incision, surgical manipulations, wound suture, extubation), systolic and diastolic blood pressure were monitored. Recovery after anaesthesia was assessed based on times of eye opening on command, spontaneous eye opening and regaining of full orientation. Increases in cardiovascular parameters by 20 % of the baseline values or more were treated with IV boluses of fentanyl, alone or with droperidol and, if necessary, by adding isoflurane 0.5 % to the inhalational mixture. Consumption of drugs was recorded. Results: Esmolol assured stable values of cardiovascular parameters that were in most critical phases of anaesthesia and operation lower than in the control group. The duration of anaesthesia did not differ between the groups. In the esmolol group, lower consumption of fentanyl, droperidol and sevoflurane was registered. Patients in the esmolol group emerged from anaesthesia faster than patients in the control group. Conclusion: Continuous IV infusion of esmolol assures better cardiovascular stability, necessitates lower consumption of analgesics and anaesthetics and results in faster emergence from general anaesthesia in elective ENT surgery.

In the Arms of Morpheus without Morphia; Mitigating the United States Opioid Epidemic by Decreasing the Surgical Use of Opioids

The opioid epidemic is a major public health issue in the United States. Exposure of opioid naïve-patients to opioids in the perioperative period is a well-documented source of continued use with one in 20 opioid-naïve surgical patients continuing to use opioids beyond 90 days. There is no association with magnitude of surgery, major versus minor, and the strongest predictor of continued use is surgical exposure. Causal factors include over reliance on opioids for intraoperative and postoperative analgesia and excessive ambulatory opioid prescribing. Opioid-induced hyperalgesia can paradoxically result from intraoperative (anesthesia controlled) opioid administration. Increasing size of initial prescription is a strong predictor of continued use necessitating procedure specific supplies limited to under 3-days. Alternative multimodal pain management (non-opioid medications and regional anesthesia) that limit opioid use must be a high priority with opioids reserved for severe breakthrough pain. Barriers to implementation of opioid-sparing pathways include reluctance to adopt protocols and apprehension about opioid elimination. Considering the number of surgeries performed annually in the United States, perioperative physicians must aggressively address modifiable factors in surgical patients. Patient care pathways need to be constructed collaboratively by surgeons and anesthesiologists with continuing feedback to optimize patient outcomes including iatrogenic opioid dependence.

Esmolol as an adjunct to general balanced anaesthesia in neurosurgery

Background/Aim: In surgery, and especially in the neurosurgical operations, maintenance of cardiovascular stability during and in the phase of the immediate postoperative recovery is of vital importance. The aim of this study was to investigate the effects of continuous esmolol infusion on the values of cardiovascular parameters and quality of the emergence from anaesthesia in neurosurgical patients. Methods: A total of 40 patients of both sexes scheduled for elective supratentorial surgery were randomly assigned to two groups. Esmolol group received intravenous (iv) infusion of esmolol dissolved in 5 % glucose solution (during the first 5 min at a rate of 0.3 mg/kg/min and thereafter at a rate of 0.1 mg/kg/min), while the ones from the control group received a 5 % glucose solution without esmolol at the same volume and rate. Cardiovascular parameters were registered at critical phases of anaesthesia and operation (induction, intubation, placement of Mayfield frame, craniotomy, skull closure, extubation). Recovery after anaesthesia was assessed based on times of eye opening on command, spontaneous eye opening and regaining of full orientation. Results: Values of systolic blood pressure and heart rate were significantly lower in the esmolol than in the control group of patients. Although the durations of anaesthesia did not differ, patients from the esmolol group required significantly less opioids and isoflurane and recovered after the anaesthesia significantly faster than the patients in the control group. Conclusion: Ultrashort-acting beta-adrenergic receptor antagonist esmolol, administered as a continuous iv infusion, assures better cardiovascular stability and smoother emergence from the balanced inhalation general anaesthesia than the control glucose infusion in elective neurosurgical patients.

Effects of the ultra-short-acting beta-blocker Esmolol infusion on cardiovascular parameters and quality of postoperative recovery in patients scheduled for elective plastic surgery

Background/Aim: Esmolol is an ultra-short-acting, easily titratable b-adrenergic receptor antagonist used for urgent treatment of hypertension and tachycardia in non-surgical and surgical settings. Aim of this clinical study was to investigate its cardiovascular effects and quality of the emergence from anaesthesia in patients scheduled for elective plastic surgery under general balanced anaesthesia. Methods: A total of 30 ASA I/II patients were randomised in two groups of similar demographic characteristics and baseline values of cardiovascular parameters. Esmolol group received esmolol dissolved in glucose 5 % as an intravenous infusion, 0.3 mg/kg/min during the first 5 min and at a rate of 0.1 mg/kg/ min thereafter. Control patients received the solvent only, at the same rate and volume. General balanced anaesthesia was induced with thiopentone sodium and fentanyl and maintained with nitrous oxide and oxygen. Neuromuscular relaxation was assured with pancuronium bromide and was antagonised at the end of operation with atropine and neostigmine. Systolic and diastolic blood pressure and heart rate were registered at all critical phases: (1) immediately prior to the induction (baseline value), (2) induction to anaesthesia, (3) tracheal intubation, (4) first skin incision, (5) surgical manipulation with organs, (6) suture of the surgical wound and (7) tracheal extubation. Drug consumption and quality of postoperative recovery were monitored. Results: In most of the critical phases of anaesthesia and operation, patients from the Esmolol group had significantly lower values of cardiovascular parameters than the patients from the Control group. Esmolol-treated patients needed less fentanyl, droperidol and pancuronium and had faster and smoother emergence from anaesthesia than the control patients. Conclusion: Esmolol improved haemodynamics and post-anaesthesia recovery in patients undergoing elective plastic surgery under general balanced anaesthesia.

Randomized, double-blind, placebo-controlled study of the analgesic effect of intraoperative esmolol for laparoscopic gastroplasty

Purpose

To evaluate the analgesic effect of esmolol in patients submitted to laparoscopic gastroplasty.

Methods

Forty patients aged between 18 and 50 years with American Society of Anesthesiologists (ASA) physical status scores of II and III who underwent gastric bypass were allocated to two groups. Group 1 patients received a 0.5-mg/kg bolus of esmolol in 30 mL of saline before induction of anesthesia, followed by an infusion at 15 µg/kg/min until the end of surgery. Group 2 patients received 30 mL of saline as a bolus and then an infusion of saline. Anesthesia included fentanyl (3 µg/kg), propofol (2-4 mg/kg), rocuronium (0.6 mg/kg), and 2% sevoflurane, with remifentanil if necessary. The following parameters were evaluated: pain intensity over 24h, remifentanil consumption, the first analgesic request, morphine consumption, and side effects.

Results

Pain intensity was lower in the esmolol group except at T0 (after extubation) and 12h postoperatively. Remifentanil supplementation, recovery time, and postoperative morphine supplementation were lower in the esmolol group. No differences in the time to the first analgesic request or side effects were found between the groups.

Conclusion

Intraoperative esmolol promotes reductions in pain intensity and the need for analgesic supplementation without adverse effects, thus representing an effective drug for multimodal analgesia in gastroplasty.

Perioperative intravenous ketamine for acute postoperative pain in adults

BACKGROUND

Inadequate pain management after surgery increases the risk of postoperative complications and may predispose for chronic postsurgical pain. Perioperative ketamine may enhance conventional analgesics in the acute postoperative setting.

OBJECTIVES

To evaluate the efficacy and safety of perioperative intravenous ketamine in adult patients when used for the treatment or prevention of acute pain following general anaesthesia.

SEARCH METHODS

We searched CENTRAL, MEDLINE and Embase to July 2018 and three trials registers (metaRegister of controlled trials, ClinicalTrials.gov and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP)) together with reference checking, citation searching and contact with study authors to identify additional studies.

SELECTION CRITERIA

We sought randomised, double-blind, controlled trials of adults undergoing surgery under general anaesthesia and being treated with perioperative intravenous ketamine. Studies compared ketamine with placebo, or compared ketamine plus a basic analgesic, such as morphine or non-steroidal anti-inflammatory drug (NSAID), with a basic analgesic alone.

DATA COLLECTION AND ANALYSIS

Two review authors searched for studies, extracted efficacy and adverse event data, examined issues of study quality and potential bias, and performed analyses. Primary outcomes were opioid consumption and pain intensity at rest and during movement at 24 and 48 hours postoperatively. Secondary outcomes were time to first analgesic request, assessment of postoperative hyperalgesia, central nervous system (CNS) adverse effects, and postoperative nausea and vomiting. We assessed the evidence using GRADE and created a 'Summary of findings' table.

MAIN RESULTS

We included 130 studies with 8341 participants. Ketamine was given to 4588 participants and 3753 participants served as controls. Types of surgery included ear, nose or throat surgery, wisdom tooth extraction, thoracotomy, lumbar fusion surgery, microdiscectomy, hip joint replacement surgery, knee joint replacement surgery, anterior cruciate ligament repair, knee arthroscopy, mastectomy, haemorrhoidectomy, abdominal surgery, radical prostatectomy, thyroid surgery, elective caesarean section, and laparoscopic surgery. Racemic ketamine bolus doses were predominantly 0.25 mg to 1 mg, and infusions 2 to 5 µg/kg/minute; 10 studies used only S-ketamine and one only R-ketamine. Risk of bias was generally low or uncertain, except for study size; most had fewer than 50 participants per treatment arm, resulting in high heterogeneity, as expected, for most analyses. We did not stratify the main analysis by type of surgery or any other factor, such as dose or timing of ketamine administration, and used a non-stratified analysis.Perioperative intravenous ketamine reduced postoperative opioid consumption over 24 hours by 8 mg morphine equivalents (95% CI 6 to 9; 19% from 42 mg consumed by participants given placebo, moderate-quality evidence; 65 studies, 4004 participants). Over 48 hours, opioid consumption was 13 mg lower (95% CI 10 to 15; 19% from 67 mg with placebo, moderate-quality evidence; 37 studies, 2449 participants).Perioperative intravenous ketamine reduced pain at rest at 24 hours by 5/100 mm on a visual analogue scale (95% CI 4 to 7; 19% lower from 26/100 mm with placebo, high-quality evidence; 82 studies, 5004 participants), and at 48 hours by 5/100 mm (95% CI 3 to 7; 22% lower from 23/100 mm, high-quality evidence; 49 studies, 2962 participants). Pain during movement was reduced at 24 hours (6/100 mm, 14% lower from 42/100 mm, moderate-quality evidence; 29 studies, 1806 participants), and 48 hours (6/100 mm, 16% lower from 37 mm, low-quality evidence; 23 studies, 1353 participants).Results for primary outcomes were consistent when analysed by pain at rest or on movement, operation type, and timing of administration, or sensitivity to study size and pain intensity. No analysis by dose was possible. There was no difference when nitrous oxide was used. We downgraded the quality of the evidence once if numbers of participants were large but small-study effects were present, or twice if numbers were small and small-study effects likely but testing not possible.Ketamine increased the time for the first postoperative analgesic request by 54 minutes (95% CI 37 to 71 minutes), from a mean of 39 minutes with placebo (moderate-quality evidence; 31 studies, 1678 participants). Ketamine reduced the area of postoperative hyperalgesia by 7 cm² (95% CI -11.9 to -2.2), compared with placebo (very low-quality evidence; 7 studies 333 participants). We downgraded the quality of evidence because of small-study effects or because the number of participants was below 400.CNS adverse events occurred in 52 studies, while 53 studies reported of absence of CNS adverse events. Overall, 187/3614 (5%) participants receiving ketamine and 122/2924 (4%) receiving control treatment experienced an adverse event (RR 1.2, 95% CI 0.95 to 1.4; high-quality evidence; 105 studies, 6538 participants). Ketamine reduced postoperative nausea and vomiting from 27% with placebo to 23% with ketamine (RR 0.88, 95% CI 0.81 to 0.96; the number needed to treat to prevent one episode of postoperative nausea and vomiting with perioperative intravenous ketamine administration was 24 (95% CI 16 to 54; high-quality evidence; 95 studies, 5965 participants).

AUTHORS' CONCLUSIONS

Perioperative intravenous ketamine probably reduces postoperative analgesic consumption and pain intensity. Results were consistent in different operation types or timing of ketamine administration, with larger and smaller studies, and by higher and lower pain intensity. CNS adverse events were little different with ketamine or control. Perioperative intravenous ketamine probably reduces postoperative nausea and vomiting by a small extent, of arguable clinical relevance.

Effects of Ketamine on Postoperative Pain After Remifentanil-Based Anesthesia for Major and Minor Surgery in Adults: A Systematic Review and Meta-Analysis

Ketamine, an N-methyl-D-aspartate (NMDA) receptor antagonist, has been postulated as an adjuvant analgesic for preventing remifentanil-induced hyperalgesia after surgery. This systematic review and meta-analysis aims to assess the effectiveness of ketamine [racemic mixture and S-(+)-ketamine] in reducing morphine consumption and pain intensity scores after remifentanil-based general anesthesia. We performed a literature search of the PubMed, Web of Science, Scopus, Cochrane, and EMBASE databases in June 2017 and selected randomized controlled trials using predefined inclusion and exclusion criteria. To minimize confounding and heterogeneity, studies of NMDA receptor antagonists other than ketamine were excluded and the selected studies were grouped into those assessing minor or major surgery. Methodological quality was evaluated with the PEDro and JADA scales. The data were extracted and meta-analyses were performed where possible. Twelve RCTs involving 156 adults who underwent minor surgery and 413 adults who underwent major surgery were included in the meta-analysis. When used as an adjuvant to morphine, ketamine reduced postoperative morphine consumption in the first 24 h and postoperative pain intensity in the first 2 h in the minor and major surgery groups. It was also associated with significantly reduced pain intensity in the first 24 h in the minor surgery group. Time to the first rescue analgesia was longer in patients who received ketamine and underwent major surgery. No significant differences in the incidence of ketamine-related adverse effects were observed among patients in the intervention group and controls. This systematic review and meta-analysis show that low-dose (≤0.5 mg/kg for iv bolus or ≤5 μg/kg/min for iv perfusion) of ketamine reduces postoperative morphine consumption and pain intensity without increasing the incidence of adverse effects.

Effect of intravenous ketamine for postoperative analgesia in patients undergoing laparoscopic cholecystectomy: A meta-analysis

BACKGROUND

We conducted a meta-analysis to assess the efficacy and safety of ketamine for reducing pain and narcotic use for patients undergoing laparoscopic cholecystectomy (LC).

METHODS

PubMed, Embase, Web of science, Medline, and Cochrane library databases were systematically searched. Randomized controlled trials (RCTs) were regarded as eligible in our study. After testing the heterogeneity across RCTs, data were aggregated for fixed/random effect model according to the I statistic. The meta-analysis was conducted using Stata 11.0 software.

RESULTS

Five studies were included, with a total sample size of 212 patients. Current meta-analysis revealed that there were significant differences regarding postoperative pain score at 12 hours [standard mean difference (SMD) = -0.322, 95% confidence interval (95% CI): -0.594 to -0.050, P = .020], 24 hours (SMD = -0.332, 95% CI: -0.605 to -0.059, P = .017), and 48 hours (SMD = -0.340, 95% CI: -0.612 to -0.068, P = .014). Ketamine intervention was found to significantly decrease narcotic use at 12 hours (SMD = -0.296, 95% CI: -0.567 to -0.025, P = .033), 24 hours (SMD = -0.310, 95% CI: -0.581 to -0.039, P = .025), and 48 hours (SMD = -0.338, 95% CI: -0.609 to -0.066, P = .015).

CONCLUSION

Ketamine appeared to significantly reduce postoperative pain and narcotic use following LC. On the basis of the current evidence available, higher quality RCTs are still required for further research.

Efficiency and safety of ketamine for pain relief after laparoscopic cholecystectomy: A meta-analysis from randomized controlled trials

OBJECTIVE

This meta-analysis aims to evaluate the effectiveness of intravenous infusion of ketamine for pain control after laparoscopic cholecystectomy (LC).

METHODS

A systematic search was performed in PubMed (1966-2017.08), Medline (1966-2017.08), Embase (1980-2017.08), ScienceDirect (1985-2017.08) and the Cochrane Library. Only randomized controlled trials (RCTs) were included. Meta-analysis was performed using Stata 11.0 software.

RESULTS

A total of six RCTs were retrieved involving 294 patients. The present meta-analysis showed that there were significant differences between groups in terms of visual analogue scale scores at 12 h (WMD = -0.478, 95% CI: -0.934 to -0.021, P = 0.040), 24 h (WMD = -0.550, 95% CI: -1.099 to -0.002, P = 0.049), and 48 h (WMD = -0.350, 95% CI: -0.678 to -0.021, P = 0.037) after LC. Significant differences were found regarding opioid consumption at 12 h (WMD = -2.820, 95% CI: -5.170 to -0.470, P = 0.019), 24 h (WMD = -3.816, 95% CI: -7.155 to -0.478, P = 0.025), and 48 h (WMD = -2.210, 95% CI: -4.046 to -0.375, P = 0.018) after LC.

CONCLUSION

Intravenous ketamine infusion significantly reduced postoperative pain scores and opioid consumption after LC. In addition, there were fewer adverse effects in the ketamine groups. Higher quality RCTs are still required for further research.

An update on pain management for elderly patients undergoing ambulatory surgery

PURPOSE OF REVIEW

The aim of this review is to provide an overview of the drugs and techniques used for multimodal postoperative pain management in the older population undergoing surgery in the ambulatory setting.

RECENT FINDINGS

Interest has grown in the possibility of adding adjuncts to a single shot nerve block in order to prolong the local anesthetic effect. The rapid and short-acting local anesthetics for spinal anesthesia are potentially beneficial for day-case surgery in the older population because of shorter duration of the motor block, faster recovery, and less transient neurologic symptoms. Another recent advance is the introduction of intravenous acetaminophen, which can rapidly achieve rapid peak plasma concentration (<15 min) following infusion and analgesic effect in ∼5 min with a duration of action up to 4 h.

SUMMARY

The nonopioid analgesic therapies will likely assume an increasingly important role in facilitating the recovery process and improving the satisfaction for elderly ambulatory surgery patients. Strategies to avoid the use of opioids and minimize opioid-related side-effects is an important advance as we expand on the use of ambulatory surgery for the aging population.

Endogenous Opiates and Behavior: 2015

This paper is the thirty-eighth consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2015 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior, and the roles of these opioid peptides and receptors in pain and analgesia, stress and social status, tolerance and dependence, learning and memory, eating and drinking, drug abuse and alcohol, sexual activity and hormones, pregnancy, development and endocrinology, mental illness and mood, seizures and neurologic disorders, electrical-related activity and neurophysiology, general activity and locomotion, gastrointestinal, renal and hepatic functions, cardiovascular responses, respiration and thermoregulation, and immunological responses.

Comparison of effects of intraoperative nefopam and ketamine infusion on managing postoperative pain after laparoscopic cholecystectomy administered remifentanil

BACKGROUND

Although intraoperative opioids provide more comfortable anesthesia and reduce the use of postoperative analgesics, it may cause opioid induced hyperalgesia (OIH). OIH is an increased pain response to opioids and it may be associated with N-methyl-D-aspartate (NMDA) receptor. This study aimed to determine whether intraoperative nefopam or ketamine, known being related on NMDA receptor, affects postoperative pain and OIH after continuous infusion of intraoperative remifentanil.

METHODS

Fifty-four patients undergoing laparoscopic cholecystectomy were randomized into three groups. In the nefopam group (N group), patients received nefopam 0.3 mg/kg at the induction of anesthesia followed by a continuous infusion of 0.065 mg/kg/h. In the ketamine group (K group), patients received ketamine 0.3 mg/kg at the induction of anesthesia followed by a continuous infusion of 3 µg/kg/min. The control group did not received any other agents except for the standard anesthetic regimen. Postoperative pain score, first time and number of demanding rescue analgesia, OIH and degrees of drowsiness/sedation scale were examined.

RESULTS

Co-administrated nefopam or ketamine significantly reduced the total amount of intraoperative remifentanil and postoperative supplemental morphine. Nefopam group showed superior property over control and ketamine group in the postoperative VAS score and recovery index (alertness and respiratory drive), respectively. Nefopam group showed lower morphine consumption than ketamine group, but not significant.

CONCLUSIONS

Both nefopam and ketamine infusion may be useful in managing in postoperative pain control under concomitant infusion of remifentanil. However, nefopam may be preferred to ketamine in terms of sedation.

Effect of ketamine combined with butorphanol on emergence agitation of postoperative patients with gastric cancer

Background

This study aimed to investigate the effect of ketamine combined with butorphanol on emergence agitation (EA) in postoperative gastric cancer patients.

Materials and methods

A total of 150 patients with gastric cancer were included and divided into group B (1 mg butorphanol before anesthesia induction, n=50), group K (1 mg/kg ketamine, n=50), and group C (1 mg butorphanol combined with 1 mg/kg ketamine, n=50). Mean arterial pressure (MAP) and heart rate (HR) at the end of operation, just before extubation (T0) and at 0 minute (T1), 5 minutes (T2), and 30 minutes (T3) after extubation were compared. Statistical analysis of recovery time, extubation time, time in postanesthesia care unit, and EA incidence and adverse reactions were performed.

Results

There were no differences among groups with respect to MAP and HR at T0 and T1 (P>0.05). Compared with patients in group C, significant reduction of MAP and HR were observed in groups K and B at T2 and T3 (P<0.05), while no differences were found between group K and group B (P>0.05). Recovery time, extubation time, time in postanesthesia care unit, and incidence of EA in group C were significantly less than those in groups K and B (P<0.05), but no differences were observed between group K and group B (P>0.05). Total incidence of adverse reactions were significantly increased in group K compared to those in groups C and B (P<0.05).

Conclusion

Injection of ketamine combined with butorphanol before anesthesia induction was more effective than injection of ketamine or butorphanol separately in the prevention of EA.

Opioid-induced redistribution of 6TM and 7TM μ opioid receptors: A hypothesized mechanistic facilitator model of opioid-induced hyperalgesia

Opioids are still the most popular form of pain treatment, but many unavoidable side effects make opioids a big challenge in effective pain management. Opioid-induced hyperalgesia (OIH), a paradoxical phenomenon, portrays an increased sensitivity to harmful stimuli caused by opioid exposure. Changes in the neural modulation are considered a major contributor to the development of OIH. Activation of opioid receptors (ORs) and corresponding downstream molecules are the vital composition of functional performance of opioids. Increasing interests were proposed of the interaction between ORs and other neural transmitter systems such as glutamatergic, GABAergic and adrenergic ones to the genesis of OIH. G protein coupled μ-opioid receptor (MOR) was studied comprehensively on its role in the development of OIH. In addition to the relationship between MOR and other neurotransmitter receptors, a new intracellular MOR that has six transmembrane (6TM) domains was identified, and found to perform a pro-nociceptive task in contrast to the counterpart 7TM isoform. A mechanistic model of OIH in which both 6TM and 7TM MORs undergoing membrane redistribution upon opioid exposure is proposed which eventually facilitates the neurons more sensitive to nociceptive stimulation than that of the preceding opioid exposure.