Comparison of the effects of dexmedetomidine versus fentanyl on airway reflexes and hemodynamic responses to tracheal extubation during rhinoplasty: A double-blind, randomized, controlled study

Comparative study between remifentanil (or fentanyl) and dexmedetomidine for the analgesia of rhinoplasty: A meta-analysis of randomized controlled trials

BACKGROUND

Remifentanil (or fentanyl) and dexmedetomidine may have some potential to improve the analgesia of rhinoplasty, and this meta-analysis aims to compare their efficacy for the analgesia of rhinoplasty.

METHODS

PubMed, Embase, Web of Science, EBSCO, and Cochrane Library databases were systematically searched, and we included randomized controlled trials (RCTs) assessing the analgesic effect of remifentanil (or fentanyl) versus dexmedetomidine for rhinoplasty.

RESULTS

Four RCTs were finally included in the meta-analysis. In patients undergoing rhinoplasty, remifentanil (or fentanyl) infusion and dexmedetomidine infusion resulted in similar good patient satisfaction (odd ratio [OR] = 2.71; 95% confidence interval [CI] = 0.63 to 11.64; P = .18), good surgeon satisfaction (OR = 1.68; 95% CI = 0.02 to 181.40; P = .83), extubation time (mean difference [MD] = 7.56; 95% CI = -11.00 to 26.12; P = .42), recovery time (MD = -2.25; 95% CI = -23.41 to 18.91; P = .83), additional analgesic requirement (OR = 0.16; 95% CI = 0 to 8.65; P = .37) and adverse events (OR = 8.50; 95% CI = 0.47 to 153.30; P = .15).

CONCLUSIONS

Remifentanil (or fentanyl) and dexmedetomidine may have comparable analgesia for patients undergoing rhinoplasty.

Effects of continuous and slow tracheal tube cuff deflation on cough reflex during extubation in noncardiac surgery patients: a randomised clinical trial

BACKGROUND

The incidence of cough reflex during extubation is 76%. Cough reflex causes severe hemodynamic fluctuations and airway complications. This prospective trial investigated the potential effects of tracheal tube cuff deflation on cough reflex during extubation.

METHODS

One hundred and twenty-six patients scheduled for operations within 3 h under general anaesthesia with orotracheal intubation were randomly assigned to one of three groups: control (C), experimental (E) or syringe (S) groups. Patients in group C underwent tracheal tube cuff deflation using a 10-ml syringe in 1 s, patients in group E underwent tracheal tube cuff deflation continuously and slowly in 5 s using a cuff pressure gauge until the pressure was zero and patients in group S underwent tracheal tube cuff deflation using a 10-ml syringe at a speed of 1 ml s^-1. The incidence and severity of cough reflexs during extubation and the incidence of postoperative airway complications within 48 h were assessed.

RESULTS

Compared with group C (60.0%), the incidence of cough reflex in group E was 9.8% (p < 0.001) and in group S was 12.5% (p < 0.001). The severity of cough reflex was graded as 2 (1-2) in group C, 1 (1-1) in group E and 1 (1-1) in group S (p < 0.001 for group comparisons). The incidence of hoarseness in group C was 0.0%, in group E was 19.5% and in group S was 5.0% (p < 0.05 for all groups, p = 0.009 between group C and E).

CONCLUSIONS

Compared with deflating a trachal tube cuff with a 10-ml syringe in 1 s, the use of a 10-ml syringe at a speed of 1 ml s^-1 or a cuff pressure guage within 5 s can both reduce the incidence of cough reflex, but deflating with a cuff pressure guage can increase the incidence of postoperative hoarseness.

TRIAL REGISTRATION

Chinese Clinical Trial Registry, identifier: ChiCTR2100054089, Date: 08/12/2021.

Recovery and post-operative analgesic efficacy from fentanyl- versus dexmedetomidine-based anesthesia in head and neck cancer surgery: A prospective comparative trial

Background

Opioids such as fentanyl are being used frequently in the management of postoperative period, whereas non-opioid drugs such as dexmedetomidine are now commonly being used as adjuvants during the perioperative period to hasten the fast recovery and better outcome in the post-operative period because of their anesthetic and analgesic property. The recovery profile was measured by the emergence of anesthesia and pain characteristics. We aimed to evaluate and compare the efficacy of dexmedetomidine and fentanyl in the surgery of head and neck cancer patients.

Methods

Prospective double-blind study on 60 patients with the American Society Anesthesiologists (ASA) grade I and II were randomly divided into two groups. Group DM received a loading dose of dexmedetomidine 1 µg/kg over 10 min followed by a maintenance dose of 0.5 µg/kg/h and Group FM received a loading dose of fentanyl 2 µg/kg/h for over 10 min followed by 1 µg/kg/h maintenance dose. Data were analyzed using a Chi-square test or Student's 't' test.

Results

The group DM was hemodynamic stable as compared to group FM. The perturbation during extubation emergence was significantly lower in group DM as compared to that in group FM. A total of four patients were severely agitated in group FM, whereas it was absent in group DM. Severe agitation was significantly different between Group FM and Group DM. The visual analog scale (VAS) was lower among patients of Group DM as compared to Group FM at all times except at 4 h.

Conclusions

The infusion of dexmedetomidine was better in controlling emergence agitation, postoperative pain, and achieving peri-operative hemodynamic stability as compared to fentanyl.

Superior laryngeal nerve block with in-line lignocaine nebulization for awake extubation response

Background and Aims:

Tracheal extubation is associated with various undesirable hemodynamic and airway responses. Various drugs are used effectively to curb these responses. But these drugs have limitations and produce side effects. Hence, the study was planned to assess the effects of superior laryngeal nerve block with inline lignocaine nebulization on awake extubation responses to suggest an alternative. The aim of this study was to assess the effect of bilateral superior laryngeal nerve block with inline lignocaine nebulization on awake extubation responses.

Material and Methods:

A study was conducted in 35 patients aged 18-60 years, posted for surgery less than 3 h under general anesthesia. The hemodynamic responses like heart rate, arterial blood pressure, and mean arterial pressure were recorded preoperatively and at 1, 5, and 10 min postextubation. Undesirable respiratory responses like bucking, severity of sore throat, and cough response were also assessed. Repeated measures analysis of variance followed by the Tukey HSD test was used to find the significance of hemodynamic parameters. Qualitative data were expressed as percentages.

Results:

Decrease in Systolic Blood Pressure, Diastolic Blood Pressure and Mean Arterial Pressure was statistically significant at 5 mins (T2) and 10 mins (T3) postextubation as compared to baseline (T0). No cough was observed postextubation in 80% patients while 20% had mild Grade 1 cough.

Conclusion:

Superior laryngeal nerve block with in-line lignocaine nebulization for awake extubation is effective in curbing the haemodynamic and respiratory responses of extubation.

Attenuation of the Airway and Cardiovascular Responses to Extubation in Chronic Smokers by Prior Treatment with Dexmedetomidine, Fentanyl, and their Combination

BACKGROUND: Respiratory complications and hemodynamic changes during and after extubation are more common than during tracheal intubation and induction of anesthesia. AIM: The objective of this study was to compare the efficacy of prior treatment with dexmedetomidine, fentanyl, and their combination on the attenuation of the airway and cardiovascular responses to extubation. METHODS: The subjects were adult chronic male smokers, representing the population in which secondary response to extubation is most common. A randomized double-blinded comparative trial was conducted on 66 patients who were 20–60 years of age, chronic male smokers, scheduled for elective surgeries, and divided into three equal groups according to given drug 20 min before the end of surgery. Group A (n = 22) received 1 ug. kg−1 dexmedetomidine, Group B (n = 22) received fentanyl 1 ug. kg−1, and Group C (n = 22) received a mixture of the previously used drugs in the same doses. Time to and quality of extubation, airway and hemodynamic responses, and post-operative agitation and sedation were recorded. RESULTS: Hemodynamic responses and quality of extubation were better in both Groups A and C than patients in Group B at the expense of increasing time to extubation, post-extubation sedation, and delayed recovery in Group C. CONCLUSION: Single-dose dexmedetomidine 1 ug. kg-1 given 15 min before extubation in chronic cigarette smokers provided better attenuation of the airway and cardiovascular responses to extubation and suctioning with better recovery profile when compared to fentanyl 1 ug. kg-1 and dexmedetomidine mixed with fentanyl in the same previous doses.

Dexmedetomidine versus midazolam on cough and recovery quality after partial and total laryngectomy - a randomized controlled trial

Background

During emergence from anesthesia after partial and total laryngectomy, excessive airway reflex and systemic hypertension may lead to subcutaneous emphysema, hemorrhage or pneumothorax.

Methods

American Society of Anesthesiologist physical status III and IV male adults undergoing elective laryngectomy were recruited and randomly allocated to receive either dexmedetomidine (group D) or midazolam (group M). The primary outcome was incidence and severity of cough. Pulse oximetry results (SpO₂), heart rate (HR), systolic blood pressure (SBP), and diastolic blood pressure (DBP) were also recorded. The visual analog scale and the Ramsay sedation scale were recorded at the points of wakefulness and departure from the post-anesthesia care unit (PACU). Rescue analgesia consumption, the time of spontaneous breath recovery, duration of the PACU stay, and the incidence of adverse effects were also recorded.

Results

The prevalence of no coughing was significantly higher in group D than in group M at the points of wakefulness and departure. HR, SBP, and DBP were significantly lower in group D compared with group M, and SpO₂ was significantly higher in group D than in group M at the moment of laryngectomy. Pain scores were lower in group D than in group M. The Ramsay score at the point of wakefulness was higher in group D than in group M. There was no difference in time to spontaneous breathing recovery, duration of the PACU stay, and incidence of adverse effects.

Conclusions

Compared with midazolam, dexmedetomidine is an effective alternative to attenuate coughing and hemodynamic changes with a low incidence of adverse events during emergence from anesthesia after partial and total laryngectomy.

Trial registration

NCT03918889, registered at clinicaltrials.gov, date of registration: March 28, 2019.

The Efficacy of Hypotensive Agents on Intraoperative Bleeding and Recovery Following General Anesthesia for Nasal Surgery: A Network Meta-Analysis

OBJECTIVES

A systematic review of the literature was conducted to evaluate hypotensive agents in terms of their adverse effects and associations with perioperative morbidity in patients undergoing nasal surgery.

METHODS

Two authors independently searched databases (Medline, Scopus, and Cochrane databases) up to February 2020 for randomized controlled trials comparing the perioperative administration of a hypotensive agent with a placebo or other agent. The outcomes of interest for this analysis were intraoperative morbidity, operative time, intraoperative bleeding, hypotension, postoperative nausea/vomiting, and postoperative pain. Both a standard pairwise meta-analysis and network meta-analysis were conducted.

RESULTS

Our analysis was based on 37 trials. Treatment networks consisting of six interventions (placebo, clonidine, dexmedetomidine, beta-blockers, opioids, and nitroglycerine) were defined for the network meta-analysis. Dexmedetomidine resulted in the greatest differences in intraoperative bleeding (-0.971; 95% confidence interval [CI], -1.161 to -0.781), intraoperative fentanyl administration (-3.683; 95% CI, -4.848 to -2.518), and postoperative pain (-2.065; 95% CI, -3.170 to -0.960) compared with placebo. The greatest difference in operative time compared with placebo was achieved with clonidine (-0.699; 95% CI, -0.977 to -0.421). All other agents also had beneficial effects on the measured outcomes. Dexmedetomidine was less likely than other agents to cause adverse effects.

CONCLUSION

This study demonstrated the superiority of the systemic use of dexmedetomidine as a perioperative hypotensive agent compared with the other five tested agents. However, the other agents were also superior to placebo in improving operative time, intraoperative bleeding, and postoperative pain.

Effects of Dexmedetomidine and ACE Genotype on Cardiovascular Response During the Decannulation Period of General Anesthesia in Patients With Essential Hypertension

PURPOSE

This study investigated the effects of dexmedetomidine on cardiovascular response during the decannulation period of general anesthesia in patients with different genotypes of angiotensin-converting enzyme (ACE) and essential hypertension.

METHODS

The present study enrolled patients with essential hypertension and American Society of Anesthesiologists class II or III who were scheduled to undergo abdominal surgery under general anesthesia. Patients were assigned to 1 of 6 groups according to ACE genotype, as detected by polymerase chain reaction-restriction fragment length polymorphism, as follows: DD; ID; II; and DD, ID, and II each with dexmedetomidine (Dex). Dexmedetomidine was intravenously infused at 0.5 μg/kg/h for 30 min before the end of surgery in groups DD (Dex), ID (Dex), and II(Dex). Anesthesia was induced and maintained by the same anesthetics in all patients. Systolic and diastolic blood pressure, heart rate (HR), ECG, and rate-pressure product were recorded before anesthesia induction; at 30 min before the end of surgery; at the end of surgery; and at 0, 1.5, 5, and 10 min after extubation.

FINDINGS

A total of 210 patients were enrolled (n = 35 per genotype). After extubation, systolic and diastolic blood pressure, HR, and RPP were increased markedly from baseline in groups DD, ID, and II; the increases were greater in groups DD and ID than in group II. No significant changes in blood pressure, HR, or RPP were found, and proper sedative was achieved in groups DD (Dex), ID (Dex), and II(Dex). The prevalences of cardiac arrhythmia were higher in groups DD and ID than in groups II, DD (Dex), ID (Dex), and II(Dex).

IMPLICATIONS

Patients essential hypertension and the ACE D allele had a strong hemodynamic response to tracheal extubation, on which dexmedetomidine was found to have both a prevention and treatment effect.

Comparision of Vital Surgical Parameters, after Administration of Midazolam and Dexmedetomidine for Conscious Sedation in Minor Oral Surgery

Aim:

The aim of this study is to compare the efficacy between midazolam and dexmedetomidine in relation to vital parameters, sedation score, pain score, cognitive judgment, and postoperative amnesia to the event in conscious sedation for minor oral surgical procedure.

Materials and Methods:

A sample size of 30 patients were selected in each group: Group M (midazolam) and Group D (dexmedetomidine).

Results:

The mean heart rate (HR) and systolic and diastolic blood pressure measurements were significantly higher in Group M after the 20^th min when compared to Group D. The visual analog scale (VAS) scores of pain were not statistically significant between the two groups during the procedure, but at the time of discharge, statistically significant VAS scores were found between the two groups. Nine (30%) patients in Group D and 21 (70%) patients in Group M showed cognitive judgment impairment with the Stroop Color and Word Test at the 30^th min.

Conclusion:

The dexmedetomidine group of patients had reduced blood pressure and HR. No significant differences were noted in oxygen saturation or in respiratory rate between the two drugs. Patients had better sedation, analgesia, lesser cognitive impairment, and amnesia in the dexmedetomidine group.

Effect of Pharmacological Agents Administered for Attenuating the Extubation Response on the Quality of Extubation: A Systematic Review

Background

Several drugs have been tried to obtund the hemodynamic extubation response but all have variable side effects that may affect the quality of short-term recovery.

Objective

Our primary objective was to evaluate the effect of pharmacological agents, such as dexmedetomidine, local anesthetics, and so on, administered for attenuating the extubation response on the quality of extubation, as judged by the presence or absence of cough, sedation, and laryngospasm/bronchospasm in adult patients who had undergone general anesthesia. A secondary objective was to evaluate the effect of these drugs on other immediate post-extubation complications such as respiratory depression, desaturation, bradycardia, hypotension, and nausea and vomiting (PONV).

Methods

This is a systematic review of (randomized controlled trials) RCTs with meta-analysis. The Medical Literature Analysis and Retrieval System Online (MEDLINE), Cumulative Index of Nursing and Allied Health Literature (CINAHL), and Cochrane Central Register of Controlled Trials (CENTRAL) databases were searched for RCTs on the effect of pharmacological agents on both the hemodynamic extubation response as well as the quality of extubation.

Results

Fourteen out of 24 included studies were subjected to a meta-analysis. The risk of cough was less likely in the intervention group as compared to control groups (OR 0.26, 95% CI 0.15 to 0.46, p<0.00001, I²=35%). Sedation, hypotension (OR= 10.47; 95% CI: 1.86, 58.80, p=0.008, I²=0%), and bradycardia (OR= 6.57; 95% CI: 2.09, 20.64, p=0.001, I²=0%) were reported with dexmedetomidine. Only one study reported laryngospasm with dexmedetomidine and two studies with opioids.

Conclusion

Dexmedetomidine 0.4 to 0.5 ug/kg was associated with smooth extubation, minimal coughing, no laryngospasm/ bronchospasm, and with stable hemodynamics, without causing respiratory depression, PONV, and desaturation. However, in higher doses (more than 0.5 ug/kg), it caused bradycardia, hypotension, and sedation. Other pharmacological agents, such as local anesthetics, calcium channel blockers, and opioids, did not attenuate cough associated with extubation.

Dexmedetomidine for Improved Quality of Emergence From General Anesthesia: A Dose-Finding Study

BACKGROUND

Dexmedetomidine provides smooth and hemodynamically stable emergence at the expense of hypotension, delayed recovery, and sedation. We investigated the optimal dose of dexmedetomidine for prevention of cough, agitation, hypertension, tachycardia, and shivering, with minimal side effects.

METHODS

In this prospective, randomized, double-blind trial, 216 adult patients were randomly assigned to dexmedetomidine 1 µg/kg (D 1), 0.5 µg/kg (D 0.5), 0.25 µg/kg (D 0.25), or control (C). During emergence, cough, agitation, hemodynamic parameters, shivering, time to extubation, and sedation scores were recorded.

RESULTS

A total of 190 patients were analyzed. The respective incidences for the groups D 1, D 0.5, and D 0.25 versus group C were 48%, 64%, and 64% vs 84% for cough-corrected P < .003 between groups D 1 and C; 33%, 34%, and 33% vs 72% for agitation-corrected P < .003 between group C and each of the study groups; and 4%, 2%, and 7% vs 22% for shivering-corrected P = .03 and corrected P = .009 between groups D 1 and D 0.5 versus group C, respectively. The percent increase from baseline blood pressure on extubation for the 3 treatment groups was significantly lower than group C. Percent increase in heart rate was lower than control in groups D 1 and D 0.5 but not in group D 0.25. Time to extubation and sedation scores were comparable. However, more hypotension was recorded during the emergence phase in the 3 treatment groups versus group C.

CONCLUSIONS

D 1 at the end of surgery provides the best quality of emergence from general anesthesia including the control of cough, agitation, hypertension, tachycardia, and shivering. D 0.5 also controls emergence phenomena but is less effective in controlling cough. The 3 doses do not delay extubation. However, they cause dose-dependent hypotension.

Medication Use and Risk of Delirium in Mechanically Ventilated Patients

One of the principal complications in patients in the intensive care unit, particularly in those receiving mechanical ventilation, is medication-induced delirium. The present study aimed to intensively analyze pharmaceutical factors affecting the development of delirium in mechanically ventilated patients using the electronic health records. The present study was designed as a retrospective case-control study. The delirium group included 500 mechanically ventilated patients. The non-delirium group included 2,000 patients who were hospitalized during the same period as the delirium group and received mechanical ventilation. A total of seven types of medications (narcotic analgesics, non-narcotic analgesics, psychopharmaceuticals, sleep aid medications, anticholinergics, steroids, and diuretics), conventionally used to manage mechanical ventilation, were found to be major risk factors associated with the occurrence of delirium. Since these medications are an integral part of managing mechanically ventilated patients, prudent protocol-based medication approaches are essential to decrease the risk of delirium.

Comparison of dexmedetomidine vs. remifentanil combined with sevoflurane during radiofrequency ablation of hepatocellular carcinoma: a randomized controlled trial

BACKGROUND

Remifentanil is widely used for ultrasound-guided percutaneous radiofrequency ablation (RFA) of small hepatocellular carcinoma (HCC). We determined whether dexmedetomidine could be an alternative to remifentanil for RFA of HCC under general anesthesia with sevoflurane.

METHODS

We prospectively randomized patients scheduled to undergo RFA for HCC to a dexmedetomidine (DEX) group or remifentanil (REMI) group (47 patients each). In the DEX group, a bolus infusion (0.4 μg kg^- 1) was started 15 min before anesthesia induction and continued at 0.2 μg kg^- 1 h^- 1 until 10 min before the end of surgery. In the REMI group, 3 μg kg^- 1 h^- 1 of remifentanil was administered from 15 min before anesthesia induction to the end of the surgery. The primary endpoint was postoperative pain intensity. Secondary endpoints included analgesic requirement, postoperative liver function, patient comfort, and hemodynamic changes. Group allocation was concealed from patients and data analysts but not from anesthesiologists.

RESULTS

Postoperative pain intensity, analgesic consumption, comfort, liver function, and time to emergence and extubation did not differ between the two groups. Heart rate, but not mean arterial pressure, was significantly lower in the DEX group than in the REMI group, at 1 min after intubation and from 30 min after the start of the surgery until anesthesia recovery. Sevoflurane concentration and dosage were significantly lower in the DEX group than in the REMI group.

CONCLUSION

During RFA for HCC, low-dose dexmedetomidine reduced the heart rate and need for inhalational anesthetics, without exacerbating postoperative discomfort or liver dysfunction. Although it did not exhibit outstanding advantages over remifentanil in terms of pain management, dexmedetomidine could be a safe alternative adjuvant for RFA under sevoflurane anesthesia.

TRIAL REGISTRATION

Chinese Clinical Trial Registry, ChiCTR-OPC-15006613 . Registered on 16 June 2015.

Comparison of the effects of oxycodone versus fentanyl on airway reflex to tracheal extubation and postoperative pain during anesthesia recovery after laparoscopic cholecystectomy: A double-blind, randomized clinical consort study

BACKGROUND

Fentanyl has been suggested to be effective for controlling airway and hemodynamic responses to tracheal extubation. This study was performed to compare the effects of oxycodone and fentanyl on airway and hemodynamic responses and postoperative pain during the recovery period in patients undergoing laparoscopic cholecystectomy.

METHODS

Ninety patients aged 18 to 65 years were randomly allocated to 1 of 3 groups: fentanyl, oxycodone, and control. Coughing responses (incidence and severity), hemodynamic responses during the recovery period, and acute postoperative pain were assessed.

RESULTS

The incidence of cough was decreased in the fentanyl and oxycodone groups compared with that in the control group at the points of awareness and extubation, and no significant difference was observed between the 2 treatment groups. Severe cough response was decreased in the fentanyl and oxycodone groups compared with that in the control group at the point of extubation, and no significant change was observed in cough severity between the 2 treatment groups. Postoperative pain scores were lower in the fentanyl and oxycodone groups than those in the control group at 5 and 30 minutes postoperatively, and no significant difference was observed between the 2 treatment groups. Hemodynamic responses did not differ among the 3 groups during the recovery period.

CONCLUSION

Oxycodone treatment before tracheal extubation reduced cough response and was as effective as fentanyl treatment for improving extubation quality. Furthermore, single boluses of fentanyl and oxycodone showed equal effectiveness in attenuating acute postoperative pain in patients undergoing laparoscopic cholecystectomy.

Neuroprotective effect of bispectral index-guided fast-track anesthesia using sevoflurane combined with dexmedetomidine for intracranial aneurysm embolization

Dexmedetomidine has sedative, anxiolytic, analgesic, anti-sympathetic, and anti-shivering effects. Dexmedetomidine might be effective in combination with sevoflurane for anesthesia, but prospective randomized controlled clinical trials with which to verify this hypothesis are lacking. In total, 120 patients who underwent embolization of an intracranial aneurysm were recruited from Anhui Provincial Hospital and Renmin Hospital of Wuhan University of China and randomly allocated to two groups. After intraoperative administration of 2% to 3% sevoflurane inhalation, one group of patients received pump-controlled intravenous injection of 1.0 μg/kg dexmedetomidine for 15 minutes followed by maintenance with 0.3 μg/kg/h until the end of surgery; the other group of patients only underwent pump-controlled infusion of saline. Bispectral index monitoring revealed that dexmedetomidine-assisted anesthesia can shorten the recovery time of spontaneous breathing, time to eye opening, and time to laryngeal mask removal. Before anesthetic induction and immediately after laryngeal mask airway removal, the glucose and lactate levels were low, the S100β and neuron-specific enolase levels were low, the perioperative blood pressure and heart rate were stable, and postoperative delirium was minimal. These findings indicate that dexmedetomidine can effectively assist sevoflurane for anesthesia during surgical embolization of intracranial aneurysms, shorten the time to consciousness and extubation, reduce the stress response and energy metabolism, stabilize hemodynamic parameters, and reduce adverse reactions, thereby reducing the damage to the central nervous system. This trial was registered at the Chinese Clinical Trial Registry (http://www.chictr.org.cn/) (registration number: ChiCTR-IPR-16008113).

Dexmedetomidine's inhibitory effects on acetylcholine release from cholinergic nerves in guinea pig trachea: a mechanism that accounts for its clinical benefit during airway irritation

BACKGROUND

Airway instrumentation can evoke upper airway reflexes including bronchoconstriction and cough which can cause serious complications including airway trauma, laryngospasm or bronchospasm which may in turn lead to difficulty with ventilation and hypoxemia. These airway events are mediated in part by irritant-induced neuronal modulation of airway tone and cough responses. We investigated whether the commonly used anesthetic agents dexmedetomidine, lidocaine or remifentanil attenuated neuronal and airway smooth muscle responses in the upper airways of guinea pigs.

METHODS

The ability of dexmedetomidine, lidocaine or remifentanil to attenuate direct cholinergic nerve stimulation, C-fiber stimulation or direct smooth muscle contraction were studied using isolated tracheal rings from male guinea pigs under four paradigms; (1) the magnitude of contractile force elicited by cholinergic electrical field stimulation (EFS); (2) the amount of acetylcholine released during cholinergic EFS; (3) the direct airway smooth muscle relaxation of a sustained acetylcholine-induced contraction and (4) the magnitude of C-fiber mediated contraction.

RESULTS

Dexmedetomidine (1-100 μM) and lidocaine (1 mM) attenuated cholinergic 30Hz EFS-induced tracheal ring contraction while remifentanil (10 μM) had no effect. Dexmedetomidine at 10 μM (p = 0.0047) and 100 μM (p = 0.01) reduced cholinergic EFS-induced acetylcholine release while lidocaine (10 μM-1 mM) and remifentanil (0.1-10 μM) did not. Tracheal ring muscle force induced by the exogenous addition of the contractile agonist acetylcholine or by a prototypical C-fiber analogue of capsaicin were also attenuated by 100 μM dexmedetomidine (p = 0.0061 and p = 0.01, respectively). The actual tracheal tissue concentrations of dexmedetomidine achieved (0.54-26 nM) following buffer application of 1-100 μM of dexmedetomidine were within the range of clinically achieved plasma concentrations (12 nM).

CONCLUSIONS

The α2 adrenoceptor agonist dexmedetomidine reduced cholinergic EFS-induced contractions and acetylcholine release consistent with the presence of inhibitory α2 adrenoceptors on the prejunctional side of the postganglionic cholinergic nerve-smooth muscle junction. Dexmedetomidine also attenuated both exogenous acetylcholine-induced contraction and C-fiber mediated contraction, suggesting a direct airway smooth muscle effect and an underlying mechanism for cough suppression, respectively.

Comparison of King Vision and Truview Laryngoscope for Postextubation Visualization of Vocal Cord Mobility in Patients Undergoing Thyroid and Major Neck Surgeries: A Randomized Clinical Trial

Background:

Visualization of vocal cords following extubation after thyroid and major neck surgeries is highly desirable for the surgeon as well as the anaesthesiologist to rule out vocal cord palsy or oedema. As the patient is emerging from general anaesthesia, it may be challenging for the anaesthesiologist to optimally visualise and grade vocal cord movement following extubation.

Setting:

Randomized clinical trial at a tertiary care centre.

Methodology:

After obtaining institutional ethics committee approval, 60 patients posted for thyroid and major neck surgeries under American Society of Anesthesiologists (ASA) grade I and II were recruited for the study. Written informed consent was obtained. Pre-operatively indirect laryngoscopy was performed in all the patients to assess baseline vocal cord function. All patients were premedicated and induced and maintained as per standardized anaesthesia protocol. Patients were randomized using a sealed envelope technique to either Group K where intubation was performed using Kings vision laryngoscope or Group T where intubation was performed using True view laryngoscope. Glottis visualization was graded in all patients and intubated. Ten minutes prior to extubation injection. dexmedetomidine 1 μg/kg was administered. Once patients satisfied extubation criteria, laryngoscopy was performed using respective video-laryngoscope in each group, patient extubated under vision and assessed for vocal cord visualization and mobility grade (VMG) and patient reactivity score (PRS). Heart rate, systolic blood pressure, diastolic blood pressure and mean arterial pressure was also noted. Total intraoperative morphine consumption was recorded. Vocal cord function was assessed again before the day of discharge by indirect laryngoscopy.

Results:

Age (P = 0.27), sex (P = 0.08), body mass index (P = 0.70), ASA (P = 0.39), mallampati class (P = 0.72) and morphine used (P = 0.39) were comparable in both groups. There was no statistically significant difference among the two groups with respect to VMG (P = 0.18). There was no statistical difference in the PRS (P = 0.06) in both groups. Increase in heart rate or mean arterial pressure from baseline was not significant statistically in both groups. Time taken for laryngoscopy during extubation was significantly less with group T as compared to group K (P = 0.000).

Conclusion:

Both Kings Vision and Truview Video-laryngoscopes provide comparable laryngoscopic view with similar patient comfort, although clinically Truview may be a better choice due to less time consumed for visualisation and rating vocal cord movement during extubation.

A Comparative Evaluation of Intravenous Dexmedetomidine and Fentanyl in Breast Cancer Surgery: A Prospective, Randomized, and Controlled Trial

Background and Aim:

Recent studies have advised narcotic less anaestheic techniques for breast cancer surgeries due to altered immune system by use of opioids. So we planned this study to compare the efficacy of dexmedtomidine with fentanyl in breast cancer surgery in terms of haemodynamic stability, anaesthetic sparing effects, recovery profile and postoperative analgesia.

Material and Methods:

In this randomized prospective controlled trial, a total of 60 female patients were randomly assigned into two groups. Patients in group F (n = 30) received a loading dose of fentanyl 2 μg/kg with maintenance dose of 0.5 μg/kg/h and in group D (n = 30) received dexmedetomidine 1 μg/kg as loading dose with maintenance dose of 0.25 μg/kg/h till the end of surgery. Hemodynamic parameters, desflurane requirement, recovery profile and postoperative analgesia were monitored and compared in both the groups.

Results:

Mean HR was less in group D compared to group F intraoperatively, before and after extubation with a significant p value. The mean MAP was also lower in group D compared to group F at all the time points. MAC requirements were found lower in group D compared to group F with a significant P < 0.001. Cognitive recovery in the form of time to respond to verbal commands, time to extubation, time to orientation was early in dexmedetomidine group.

Conclusion:

Dexmedtomidine can be used as suitable alternative to fentanyl in breast cancer surgeries due to better hemodynamic stability, anaesthetic sparing effects and better recovery profile.

Intravenous Dexmedetomidine Infusion Compared with that of Fentanyl in Patients Undergoing Arthroscopic Shoulder Surgery under General Anesthesia

Background

Anesthesia for arthroscopic shoulder surgery is challenging due to the need for oligaemic surgical field as well as a good postoperative recovery profile.

Aim

The present study was prospective, randomized to evaluate the efficacy of dexmdetomidine infusion compared to that of fentanyl in patients undergoing arthroscopic shoulder surgery under general anesthesia.

Patients and Methods

A total of 60 patients aged from thirty to fifty years, American Society of Anesthesiologists Class I/II of either sex for arthroscopic shoulder surgery, were included. The patients were divided into two groups of 30 patients each. Group I received dexmedetomidine loading 1 μg/kg over 10 min followed by maintenance 0.5 μg/kg/h and Group II Fentanyl loading 1 μg/kg followed by maintenance 0.5 μg/kg/h.

Measurements

Hemodynamic readings (Heart rate HR, and mean arterial blood pressure MAP) were recorded after the start of the study drug infusion (T1), after intubation (T2), then every 15 minutes till the end of surgery (T15, T30, T45, T60, T75, T90). In the PACU, MAP, and HR were recorded on arrival, after 30 min, 1 hr, and 2 hrs (R0, R30, R1 hr, R2 hr) Postoperative analgesia was assessed by visual analogue scale (VAS), Modified Observers's Assessment of Alertness and Sedation OAA/S was recorded on arrival to PACU.

Results

This study showed that in the dexmedatomidine group there was statistically significant decrease of MAP and HR after drug infusion up to two hours in the recovery period, more sedation, better control of pain and surgeon satisfaction.

Conclusion

Iv infusion of dexamedatomidine may be an attractive option during arthroscopic shoulder surgery as it provided a better hypotensive anesthesia by lowering MAP and HR which leads to better surgical field and surgeon satisfaction than iv infusion fentanyl along with a better postoperative VAS.

Rapid and reliable smooth extubation - Comparison of fentanyl with dexmedetomidine: A randomized, double-blind clinical trial

BACKGROUND

Fentanyl and dexmedetomidine have been tried to attenuate airway and circulatory reflexes during emergence and extubation individually but have not been compared with respect to the level of sedation to evolve a reliable technique for rapid and smooth extubation.

AIM

To compare the effects of fentanyl and dexmedetomidine in attenuating airway and circulatory reflexes during emergence and extubation of the endotracheal tube.

SETTING AND DESIGN

This double-blind, randomized, controlled study was done in patients undergoing surgery under general anesthesia belonging to the American Society of Anesthesiologists physical status 1 or 2.

METHODOLOGY

All patients received a standardized anesthetic protocol. Patients were randomized to receive either fentanyl 1 μg/kg or dexmedetomidine 0.75 μg/kg. Fifteen minutes before expected last surgical suture, isoflurane was cutoff and equal amount of test solution was given when train-of-four ratio was 0.3. The degree of sedation, airway, and circulatory responses at the time of suction and extubation were analyzed.

STATISTICAL ANALYSIS USED

Chi-square test for nonparametric data and t-test for parametric data.

RESULTS

Heart rate (HR) was comparable in both the groups until endotracheal extubation. Later, there was rise in HR in fentanyl group. There was stastisticaly significant drop in blood pressure at 5 min after test drug administration in both the groups. Airway response for suctioning and extubation was better in dexmedetomidine group and it was associated with better sedation score than fentanyl group.

CONCLUSION

Single dose of 0.75 μg/kg dexmedetomidine given 15 min before extubation provides smooth extubation when compared to fentanyl.

The effects of dexmedetomidine on attenuation of hemodynamic changes and there effects as adjuvant in anesthesia during laparoscopic surgeries

Background:

As an anesthetic adjuvant dexmedetomidine has been shown to provide good perioperative hemodynamic stability with minimum alveolar concentration sparing effect on inhalational anesthetic agents during laparoscopic surgeries performed under general anesthesia.

Aim:

The study was planned to investigate the effects of dexmedetomidine on attenuation of hemodynamic changes and requirements of intra-operative analgesic and inhalational anesthetic during laparoscopic surgeries and its postoperative side effects.

Materials and Methods:

A total of 70 patients scheduled for elective laparoscopic surgeries were randomized to receive bolus infusion of dexmedetomidine (group D) or saline (group S) 1 mcg/kg/h, followed by continuous infusion of the same, at the rate of 0.5 mcg/kg/h. Anesthesia was maintained with nitrous oxide in oxygen, muscle relaxant and isoflurane. Supplementation with end-tidal isoflurane was considered when heart rate (HR) and mean arterial blood pressure (BP) exceeded 20% of the baseline value. Hemodynamics, end-tidal isoflurane concentration and adverse events were recorded.

Results:

Intra-operative mean HR and mean BP in group D were lower than group S (P < 0.05) throughout the laparoscopy surgery. Requirement of intra-operative fentanyl, end-tidal isoflurane and postoperative tramadol were significantly more in group S compared to group D (P < 0.05) Statistically significant nausea and vomiting were noted in group S. Undue sedation and other adverse effects are comparable in both the groups.

Conclusion:

Dexmedetomidine as an adjuvant in general anesthesia for laparoscopic surgeries provided a stable hemodynamic profile in the perioperative period and effectively blunted pressor response to intubation and extubation, leading to minimal requirements for additional analgesics and potent inhalational agents. There were less adverse events.

Comparative Evaluation of Bolus Administration of Dexmedetomidine and Fentanyl for Stress Attenuation During Laryngoscopy and Endotracheal Intubation

BACKGROUND

Laryngoscopy and endotracheal intubation can cause hypertension and tachycardia which can result in myocardial ischemia or stroke in vulnerable people. The objective of our study was to compare the efficacy of bolus dose of dexmedetomidine and fentanyl in attenuating haemodynamic stress responses following laryngoscopy and intubation.

MATERIALS AND METHODS

Sixty patients who were fixed to undergo elective surgeries under general anaesthesia were randomly divided into 2 groups. Group 1 received 1 mcg/kg of dexmedetomidine over 10 minutes and group 2 received fentanyl 2mcg/kg before induction. Anaesthesia was standardized in both the groups and vital parameters were recorded for up to 10 minutes after intubation.

RESULTS

Dexmedetomidine in a dose of 1mcg/kg prevented an increase in heart rate following laryngoscopy when compared to fentanyl group. This effect lasted for 10 minutes after intubation is performed. Though dexmedetomidine prevented an increase in blood pressure, this effect was statistically significant only for 2 minutes after intubation when compared to fentanyl group.

CONCLUSION

Attenuation of rise in heart rate and blood pressure following laryngoscopy and endotracheal intubation was better with 1mcg/kg of dexmedetomidine when compared to fentanyl.

Efficacy of dexmedetomidine on postoperative nausea and vomiting: a meta-analysis of randomized controlled trials

PURPOSE

Postoperative nausea and vomiting (PONV) is a frequent complication in postoperative period. The aim of the current meta-analysis was to assess the efficacy of dexmedetomidine on PONV.

METHODS

Two researchers independently searched PubMed, Embase and Cochrane Central Register of Controlled Trials for randomized controlled trials (RCTs). The meta-analysis was performed with Review Manager.

RESULTS

Eighty-two trials with 6,480 patients were included in this meta-analysis. Dexmedetomidine reduced postoperative nausea (Risk Ratio (RR) = 0.61, 95% confidence interval (CI): 0.50 to 0.73) and vomiting (RR = 0.48, 95% CI: 0.36 to 0.64) compared with placebo, with an effective dose of 0.5 ug/kg (RR = 0.46, 95% CI: 0.34 to 0.62) and 1.0 ug/kg (RR = 0.29, 95% CI: 0.12 to 0.75), respectively. The antiemetic effect can only be achieved intravenously, not epidurally or intrathecally. The efficacy of dexmedetomidine was similar to that of widely used agents, such as propofol, midazolam etc., but better than opioid analgesics. Moreover, application of dexmedetomidine reduced intraoperative requirement of fentanyl (Standard Mean Difference = -1.91, 95% CI: -3.20 to -0.62).

CONCLUSIONS

The present meta-analysis indicates that dexmedetomidine shows superiority to placebo, but not to all other anesthetic agents on PONV. And this efficacy may be related to a reduced consumption of intraoperative opioids.

Comparison of Dexmedetomidine versus Propofol for Sedation after Uvulopalatopharyngoplasty

Background

Adequate sedation is important in the post-anesthesia care unit (PACU) following uvulopalatopharyngoplasty (UPPP) to ensure patient comfort and decrease the duration of mechanical ventilation (MV), PACU stay, and bleeding. This study aimed to compare dexmedetomidine and propofol as sedatives after UPPP in the PACU.

Material/Methods

We randomized 124 mechanically ventilated adults following UPPP who were managed in the PACU of the General Hospital of the Shenyang Military Region between January 2014 and June 2014, to receive either dexmedetomidine or propofol. The patients in the propofol group received an infusion of propofol (3 mg/kg/h) titrated up to 6 mg/kg/h to attain a Ramsay sedation score ≥4. The dexmedetomidine group patients received 1.0 μg/kg of dexmedetomidine over a period of 10 minutes and then 0.5 to 1.0 μg/kg/h infusion to maintain a Ramsay sedation score ≥4.

Results

Bispectral index (BIS) values were significantly lower in the dexmedetomidine group than in the propofol group at Ramsay sedation scores of 4 and 5. The mean times to spontaneous breathing, waking, and extubation were shorter in the dexmedetomidine group. Tramadol requirement was significantly reduced in the dexmedetomidine group (P<0.05). Incidence of cough during the extubation process in the propofol group was higher than in the dexmedetomidine group. After extubation, Bruggemann comfort scale (BCS) and Rass agitation scores (RASS) were decreased in the dexmedetomidine-sedated patients.

Conclusions

Dexmedetomidine provides safe and effective sedation for post-UPPP surgical patients and significantly reduces the use of analgesics, with minimal adverse effects.

Efficacy of dexmedetomidine on postoperative nausea and vomiting: a meta-analysis of randomized controlled trials

PURPOSE

Postoperative nausea and vomiting (PONV) is a frequent complication in postoperative period. The aim of the current meta-analysis was to assess the efficacy of dexmedetomidine on PONV.

METHODS

Two researchers independently searched PubMed, Embase and Cochrane Central Register of Controlled Trials for randomized controlled trials (RCTs). The meta-analysis was performed with Review Manager.

RESULTS

Eighty-two trials with 6,480 patients were included in this meta-analysis. Dexmedetomidine reduced postoperative nausea (Risk Ratio (RR) = 0.61, 95% confidence interval (CI): 0.50 to 0.73) and vomiting (RR = 0.48, 95% CI: 0.36 to 0.64) compared with placebo, with an effective dose of 0.5 μg/kg (RR = 0.46, 95% CI: 0.34 to 0.62) and 1.0 μg/kg (RR = 0.29, 95% CI: 0.12 to 0.75), respectively. The antiemetic effect can only be achieved intravenously, not epidurally or intrathecally. The efficacy of dexmedetomidine was similar to that of widely used agents, such as propofol, midazolam etc., but better than opioid analgesics. Moreover, application of dexmedetomidine reduced intraoperative requirement of fentanyl (Standard Mean Difference = -1.91, 95% CI: -3.20 to -0.62).

CONCLUSIONS

The present meta-analysis indicates that dexmedetomidine shows superiority to placebo, but not to all other anesthetic agents on PONV. And this efficacy may be related to a reduced consumption of intraoperative opioids.

Attenuation of circulatory and airway responses to endotracheal extubation in craniotomies for intracerebral space occupying lesions: Dexmedetomidine versus lignocaine

OBJECTIVES

The objective of the study is to compare the effect of dexmedetomidine versus lignocaine in attenuation of circulatory and airway responses during endotracheal extubation in craniotomies for intracerebral space occupying lesions (ICSOL).

MATERIALS AND METHODS

A total of 50 patients of American Society of Anesthesiologists Grade I and II of either sex, aged 18-50 years undergoing craniotomies for non-vascular ICSOL under general anesthesia were divided into two groups according to drug received. Group D (n = 25) received dexmedetomidine (0.5 mcg/kg) whereas group L (n = 25) received lignocaine (1.5 mg/kg). Both the drugs were given 5 min before the extubation over a period of 60 s. Values for heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), were recorded just before (A0) and 1, 3, 5 (A1, A3, A5) min after the study drug administration, at extubation (E) and 1, 3, 5, 10, 15 min after extubation (E1, E3, E5, E10 and E15). Respiratory rate, oxygen saturation and airway responses like coughing, breath-holding, laryngospasm/bronchospasm were recorded only at extubation (E) and 1, 3, 5, 10, 15 min after extubation (E1, E3, E5, E10, E15). Quality of extubation was recorded with four point scale. After extubation all these patients were also observed for sedation by Ramsey sedation score.

RESULTS

Both groups showed a statistically significant increase (D < L) in HR, SBP and DBP during (E) and immediately after extubation (E1) (P < 0.05). Dexmedetomidine (72%) produced a higher degree of sedation (Grade 3) as compare with lignocaine (0%) and with no incidence of coughing or breath holding (P < 0.05).

CONCLUSION

Single dose of dexmedetomidine (0.5 mcg/kg) given 5 min before extubation produced significant attenuation of circulatory and airway responses produced during extubation as compared to Lignocaine (1.5 mg/kg) in ICSOL.

Efficacy of dexmedetomidine on postoperative shivering: a meta-analysis of clinical trials

PURPOSE

Shivering is a frequent complication in the postoperative period. The aim of the current meta-analysis was to assess the efficacy of dexmedetomidine on postoperative shivering.

METHODS

Two researchers independently searched PubMed, EMBASE and the Cochrane Central Register of Controlled Trials for controlled clinical trials. The meta-analysis was performed by Review Manager.

RESULTS

Thirty-nine trials with 2,478 patients were included in this meta-analysis. Dexmedetomidine reduced postoperative shivering compared with placebo (risk ratio [RR] = 0.26; 95% confidence interval [CI]: 0.20 to 0.34), with a minimum effective dose of 0.5 µg·kg(-1) (RR = 0.36; 95% CI: 0.21 to 0.60). The anti-shivering effect can be achieved both intravenously and epidurally when administered within two hours prior to the end of surgery. The efficacy of dexmedetomidine was similar to widely used anti-shivering agents, such as fentanyl, meperidine, tramadol, clonidine and so on; however, dexmedetomidine may increase the incidence of sedation, hypotension, bradycardia and dry mouth.

CONCLUSIONS

The present meta-analysis indicates that dexmedetomidine shows superiority over placebo, but not over other anti-shivering agents. Therefore, considering its high price and potential adverse events, dexmedetomidine may not be appropriate solely for the purpose of the prevention of postoperative shivering.

A randomized controlled trial of the effect of preoperative dexmedetomidine on the half maximal effective concentration of propofol for successful i-gel insertion without muscle relaxants

BACKGROUND

Dexmedetomidine is a useful anesthetic adjuvant for general anesthesia. We determined whether preoperative dexmedetomidine administration could reduce the half maximal effective concentration (EC50) of propofol for successful i-gel insertion without muscle relaxants.

METHODS

Thirty-seven patients were randomly allocated to one of two groups. In the dexmedetomidine group (n = 19), dexmedetomidine (1 µg/kg) was loaded for 10 min preoperatively. In the control group (n = 20), the same volume of 0.9% normal saline was administered in the same manner. The EC50 of propofol for successful i-gel insertion was determined using Dixon's up-and-down method. The EC50 of propofol was calculated as the midpoint concentration after at least six crossover points had been obtained. For successful i-gel insertion, all of the following four factors were required—(1) no major movement of the body within 1 min of insertion, (2) no significant resistance to mouth opening, (3) cough ≤2, and (4) visible square wave capnogram without air leakage at a peak airway pressure of <10 cmH2O. Mean blood pressure (MBP) and heart rate (HR) were monitored during the peri-insertion period of i-gel.

RESULTS

The EC50 of propofol for successful i-gel insertion was 3.18 μg/mL in the dexmedetomidine group and 6.75 μg/mL in the control group (p < 0.001). The incidence of hypotension (MBP <80% of the baseline) during the peri-insertion period of i-gel was higher in the control group (p = 0.001), whereas the incidence of bradycardia (HR <80% of the baseline) was higher in the dexmedetomidine group (p = 0.001).

CONCLUSIONS

Preoperative dexmedetomidine reduced the EC50 of propofol for successful i-gel insertion without muscle relaxants.

Effect of intraoperative Dexmedetomidine infusion on Sevoflurane requirement and blood glucose levels during entropy-guided general anesthesia

Background:

Dexmedetomidine has been shown to blunt the stress response to surgery. Hence a study was designed to evaluate the effect of intravenous (IV) Dexmedetomidine infusion during general anesthesia for abdominal surgeries on blood glucose levels and on Sevoflurane requirements during anesthesia.

Materials and Methods:

Forty patients scheduled for abdominal surgery under general anesthesia were divided into Dexmedetomidine (D) group and Placebo (P) group of 20 each. Group D received a loading dose of Inj. Dexmedetomidine at 1 μg/kg/10 min diluted to 20 mL, followed by maintenance with 0.5 μg/kg/h., till the end of surgery. Group P received similar volume of IV normal saline. Anesthesia was maintained with nitrous oxide in oxygen and Sevoflurane keeping entropy between 40 and 60. Data were analyzed using students t test, chi square test and Fisher Exact test as applicable.

Results:

During the first postoperative hour, Dexmedetomidine group showed blood glucose levels of 118.2 ± 16.24 mg/dL, compared to placebo group which was 136.95 ± 19.76 mg/dL and it was statistically significant (P < 0.01). Mean hourly Sevoflurane requirement in Group D was 11.10 ± 2.17 mL, compared to 15.45 ± 3.97 mL in placebo group. In peri-operative period, the heart rate and MAP were significantly lower in Group D, when compared to placebo. Patients in Group D were better sedated and post-operative pain score was better in Group D compared to Group P.

Conclusion:

IV Dexmedetomidine was effective in blunting stress response to surgical trauma as indicated by lower blood glucose levels, and reduces Sevoflurane requirements during entropy guided general anesthesia without affecting time for extubation.

A double blind, randomized, controlled trial to study the effect of dexmedetomidine on hemodynamic and recovery responses during tracheal extubation

Background:

The α2-adrenoreceptor agonist, dexmedetomidine, provides excellent sedation with minimal cardiovascular instability or respiratory depression and may be a useful adjunct to facilitate smooth tracheal extubation.

Materials and Methods:

Fifty American Society of Anesthesiologists grade I-II patients, aged 20-45 years, scheduled for elective general surgical, urological and gynecological surgeries were studied after randomization into two groups. Group A and B, received an intravenous infusion of dexmedetomidine 0.75 mcg/kg or placebo respectively, over 15 minutes before anticipated time of end of surgery, in a double blind manner. Anesthesia techniques were standardized. Heart rate, systolic, diastolic, mean arterial pressures were recorded while starting injection, at 1, 3, 5, 10, 15 minutes after starting injection, during extubation, at 1, 3, 5 minutes after extubation, and thereafter every 5 minutes for 30 minutes. Quality of extubation was evaluated on a 5 point scale and postoperative sedation on a 6 point scale. Any event of laryngospasm, bronchospasm, desaturation, respiratory depression, vomiting, hypotension, undue sedation was noted.

Results:

Heart rate, systolic, diastolic, mean arterial pressures were significantly higher in group B (P < 0.05). Extubation quality score of majority of patients was 2 in group A and 3 in group B. Sedation score of most patients was 3 in group A and 2 in group B. Bradycardia and hypotension incidences were higher in group A. One patient in group A, two patients in group B had vomiting. No patient had any other side effects.

Conclusion:

Dexmedetomidine 0.75 mcg/kg administered 15 minutes before extubation, stabilizes hemodynamics and facilitates smooth extubation.