Intranasal Dexmedetomidine as a Sedative Premedication for Patients Undergoing Suspension Laryngoscopy: A Randomized Double-Blind Study

Nebulized Versus Intravenously Administered Dexmedetomidine for Obtunding Hemodynamic Responses to Laryngoscopy and Tracheal Intubation: A Randomized Double-Blind Comparative Study

Introduction Intravenous dexmedetomidine is known to cause major adverse effects such as bradycardia, hypotension, cardiac arrhythmias, and heart block when used as premedication for attenuation of the laryngoscopy and intubation response, limiting its routine use. Thus, it is important to study other routes of administration of dexmedetomidine. Objectives To compare the hemodynamic response and sedation score between intravenous and nebulized dexmedetomidine as premedication for the attenuation of the laryngoscopy and intubation response. Materials and methods In this study, 60 patients fulfilling inclusion criteria undergoing surgeries under general anesthesia (ASA Grade I and II) were randomly allocated into two groups of 30 patients each. Group IV received intravenous 1 mcg/kg dexmedetomidine in 100 mL normal saline, and Group IN received nebulization with 1 mcg/kg dexmedetomidine diluted to a total volume of 5 cc of normal saline, 30 minutes prior to the induction of general anesthesia. Sedation scores were calculated using the Ramsay sedation score at 20 minutes after the administration of the drug; patients were induced by the standard protocol, and laryngoscopy was performed. Vitals were recorded before the administration of the drug and after intubation at stipulated time intervals. Results The median heart rate becomes significantly lower at 15 minutes (70 vs. 76.5) and 20 minutes (66 vs. 76) after induction among Group IV as compared to Group IN. The median systolic blood pressure was significantly lower at 20 minutes in Group IV (110 mmHg) than in Group IN (119 mmHg). The median diastolic blood pressure was significantly lower at 10 minutes (76 vs. 79), 15 minutes (70 vs. 77), and 20 minutes (69 vs. 78.5) in Group IV than in Group IN. The median of mean arterial pressure was significantly lower at 15 minutes (84.8 vs. 91.5) and 20 minutes (83 vs. 92) in Group IV than in Group IN. A comparison of vitals after induction shows that the median heart rate, systolic blood pressure, diastolic blood pressure, and mean arterial pressure were significantly lower statistically among Group IV as compared to Group IN at 0, 1, 3, 5, 10, 15, and 30 minutes after induction (except for systolic blood pressure at 3 minutes). The median sedation score was lower in Group IN (0) than in Group IV (1); this difference is statistically significant. Conclusion The obtundation of hemodynamic responses following laryngoscopy and maintaining hemodynamics intraoperatively is statistically better with nebulized dexmedetomidine compared to intravenous dexmedetomidine.

Nebulized dexmedetomidine for attenuating hemodynamic response to laryngoscopy and endotracheal intubation in adult patients undergoing surgeries under general anaesthesia: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Sympathetic stimulation associated with laryngoscopy and endotracheal intubation (ETI) may lead to adverse cardio-/cerebro-vascular events in susceptible patients. Nebulization is a novel route for dexmedetomidine administration providing a large surface area for absorption while avoiding bradycardia and hypotension associated with intravenous route. We aimed to evaluate the efficacy and safety of dexmedetomidine nebulization for attenuating hemodynamic response to ETI in adult patients undergoing surgery under general anaesthesia.

METHODS

This systematic review was registered prospectively in the International Prospective Register of Systematic Reviews (CRD42023403624). PubMed, Embase (OvidSP), Cochrane library, Scopus (Elsevier), Web of Science (Clarivate) and Google Scholar were systematically searched from database inception until March 31, 2023. Two reviewers independently screened titles, abstracts and then full text against pre-specified eligibility criteria. Randomized controlled trials (RCTs) assessing effect of dexmedetomidine nebulization on hemodynamic response to ETI in adult patients undergoing surgeries under general anaesthesia were included. All studies reporting heart rate and systolic blood pressure at baseline and various time points after ETI were included. A pre-piloted data extraction form, Cochrane revised risk-of-bias tool (ROB 2) tool, GRADE approach and RevMan 5.4.1 (Cochrane Collaboration, Copenhagen, Denmark) were used for data extraction, risk of bias assessment, rating certainty of evidence and data synthesis respectively. Mean difference and relative risk with 95% Confidence Interval (CI) were used for continuous and dichotomous variables respectively.

RESULTS

Six RCTs randomized 480 patients with ASA I/II patients aged < 60 years of age and undergoing elective surgeries to receive either dexmedetomidine (n = 240) or saline nebulization (n = 240). Except for one RCT which used 2 μg/kg, all other RCTs used dexmedetomidine dose of 1 μg /kg. Heart rate, systolic, diastolic and mean blood pressure were significantly lower in the dexmedetomidine group at all the measured time points after laryngoscopy and ETI with the only exception being systolic blood pressure at 3 min [mean difference -13.86 (95% CI -30.01 to 2.99), p = 0.09]. Bradycardia and hypotension as adverse effects were absent across the included studies. However, only one-third of the included studies had a low risk of bias and strength of evidence was very low according to the GRADE assessment.

CONCLUSIONS

Compared to placebo, premedication with dexmedetomidine nebulization was associated with lower HR and BP following ETI without any risk of bradycardia and hypotension. However, the strength of evidence was very poor and came from just one country. Future well designed and conducted studies in different populations are warranted.

TRIAL REGISTRATION

PROSPERO Registration number: CRD42023403624.

The Effect of Intranasal Dexmedetomidine on Emergence Delirium Prevention in Pediatric Ambulatory Dental Rehabilitation Under General Anesthesia: A Randomized Clinical Trial

Purpose

Sevoflurane is the preferred anesthetic agent for induction and maintenance of ambulatory surgery due to its property of fast onset and recovery. However, it has been recognized as one of the major contributors of emergence delirium. The aim of this study was to evaluate the preventive effect of intranasal dexmedetomidine on the occurrence of emergence delirium in pediatric patients under general anesthesia with sevoflurane.

Patients and Methods

Ninety pediatric patients undergoing dental rehabilitation under sevoflurane anesthesia were enrolled in this study. The patients were divided into three groups (n=30 each in the 2 μg/kg dexmedetomidine, 1 μg/kg dexmedetomidine, and control with saline groups). The same volume (0.02mL/kg) of the mixed solution was dropped into the nasal cavity of the children 30 minutes before surgery. We used the Pediatric Anesthesia Emergence Delirium Scale (PAED) to assess the level and incidence of delirium in the post-anesthesia care unit.

Results

Compared with the control group, prophylactic use of different dosages of intranasal dexmedetomidine significantly reduces the incidence of ED and severe ED in PACU (P<0.001). Intranasal administration of 2 μg/kg dexmedetomidine was associated with a better acceptance of mask induction and a better tolerance of separation with parents.

Conclusion

Both 2 μg/kg and 1 μg/kg intranasal dexmedetomidine can achieve ED preventive effects in PACU in dental rehabilitation under general anesthesia. A dosage of 2 μg/kg is more effective in preventing severe ED and providing better mask acceptance.

Esketamine versus Sufentanil Applied Prior to Placement of Suspension Laryngoscope

OBJECTIVE

In laryngeal microsurgery, the insertion of the suspension laryngoscope is a strong stimulus that may cause hemodynamic fluctuations and adverse cardiovascular events. The purpose of this study was to compare the effect of preemptive treatment with esketamine and sufentanil on maintaining hemodynamics and reducing the occurrence of adverse cardiovascular events during the insertion of suspension laryngoscope.

METHODS

In this double-blind randomized controlled trial, patients undergoing general anesthesia for laryngeal microsurgery were randomly assigned (1:1) to esketamine 0.5 mg kg-1 (esketamine group) and sufentanyl 0.125 μg kg-1 (sufentanil group) before inserting the laryngoscope, respectively.

RESULTS

During the insertion of suspension laryngoscope, the incidence of bradycardia (HR < 60 beats/min) was 39.3% (22/56) in esketamine group, lower than 60.0% (33/55) in sufentanil group (odds ratio [OR], 2.32 [95% CI, 1.11-5.08]; p = 0.029). The incidence of hypotension (MAP <65 mmHg) was 33.9% (19/56) in esketamine group, lower than 56.4% (31/55) in sufentanil group (odds ratio [OR], 2.52 [95% CI, 1.91-5.27]; p = 0.018). The frequency of hypotension in esketamine group was lower than that in sufentanil group (0.36 ± 0.52 vs. 0.56 ± 0.50, p = 0.035). The time-weighted average of HR dropping above 30% of baseline was smaller in esketamine group than in sufentanil group (0.52 ± 2.06 vs. 1.08 ± 2.77, p = 0.006).

CONCLUSIONS

These findings showed that compared with preemptive treatment of sufentanil (0.125 μg kg-1 ), esketamine (0.5 mg kg-1 ) was effective in reducing the incidence of cardiovascular adverse events, including bradycardia and hypotension induced by the insertion of suspension laryngoscope during the laryngeal microsurgery.

LEVEL OF EVIDENCE

2 Laryngoscope, 133:3021-3027, 2023.

Two-center randomized controlled trial comparing oral chloral hydrate and intranasal combination of dexmedetomidine and ketamine for procedural sedation in children: study protocol

BACKGROUND

Oral chloral hydrate is widely used in pediatric sedation. Intranasal dexmedetomidine has been increasingly used for pediatric sedation; however, its improvement is warranted. The combination of dexmedetomidine with ketamine can improve onset and hemodynamic stability while maintaining sedative efficacy. This study aims to determine the efficacy and safety of intranasal combination of dexmedetomidine and ketamine compared to oral chloral hydrate.

METHODS

This is a prospective, parallel-arm, single-blinded, two-center, superiority randomized controlled trial with 1:1 allocation, designed to compare the effects of intranasal combination of dexmedetomidine and ketamine with those of oral chloral hydrate. We shall enroll 136 patients aged < 7 years old in this study. Prior to the procedure, we shall randomize each patient into the control group (oral chloral hydrate 50 mg/kg) or study group (intranasal dexmedetomidine 2 μg/kg and ketamine 3 mg/kg). The primary outcome will be the rate of achieving an adequate sedation level (6-point Pediatric Sedation State Scale 1, 2, or 3) within 15 min. In addition, we shall measure the sedation time, sedation failure rate, completion of procedure, adverse events, patient acceptance, and physician satisfaction.

DISCUSSION

This study will provide evidence of the efficacy and safety of the intranasal combination of dexmedetomidine and ketamine in comparison with oral chloral hydrate.

TRIAL REGISTRATION

ClinicalTrials.gov , NCT04820205. Registered on 19th March 2021.

What Is the Role of Dexmedetomidine in Modern Anesthesia and Critical Care?

Dexmedetomidine's unique sedative properties have led to its widespread use. Dexmedetomidine has a beneficial pharmacologic profile including analgesic sparing effects, anxiolysis, sympatholysis, organ-protective effects against ischemic and hypoxic injury, and sedation which parallels natural sleep. An understanding of predictable side effects, effects of age-related physiologic changes, and pharmacokinetic and pharmacodynamic effects of dexmedetomidine is crucial to maximize its safe administration in adults and children. This review focuses on the growing body of literature examining advances in applications of dexmedetomidine in children and adults.

Anaesthetic Approach to Enhanced Recovery after Surgery for Kidney Transplantation: A Narrative Review

Enhanced recovery after surgery (ERAS) protocols are designed to reduce medical complications, the length of hospital stays (LoS), and healthcare costs. ERAS is considered safe and effective for kidney transplant (KTx) surgery. KTx recipients are often frail with multiple comorbidities. As these patients follow an extensive diagnostic pathway preoperatively, the ERAS protocol can ideally be implemented at this stage. Small singular changes in a long perioperative pathway can result in significant positive outcomes. We have investigated the current evidence for an ERAS pathway related to anaesthetic considerations in renal transplant surgery for adult recipients.

Evaluation of Nebulised Dexmedetomidine Given Pre-operatively to Attenuate Hemodynamic Response to Laryngoscopy and Endotracheal Intubation: A Randomised Control Trial

Background and aim

A variety of medications have been studied to reduce the hemodynamic response to laryngoscopy and intubation. Dexmedetomidine has been used intravenously in many studies to reduce the hemodynamic response to laryngoscopy and intubation. In high-risk patients, this pressor response can increase morbidity and mortality. As dexmedetomidine has a good bioavailability via the nebulisation route, we formulated this study to evaluate the effect of nebulised dexmedetomidine on the hemodynamic response to laryngoscopy and endotracheal intubation.

Methods

This is a prospective, randomised controlled trial conducted on 100 patients with the American Society of Anesthesiologists grade I and II. The primary objective of the study was to see if nebulised dexmedetomidine at a dose of 1 microgram/kg could reduce the stress reaction to laryngoscopy and intubation. The secondary objective was to study the dose sparing effect of nebulised dexmedetomidine on the amount of propofol used during induction of general anaesthesia. The study population was randomly divided into two groups: group A (n = 50) included patients nebulised with dexmedetomidine 1 microgram/kg and group B (n = 50) included patients nebulised with 5 ml saline 30 minutes before induction of anaesthesia in a sitting position.

Results

The demographics were similar in both groups. Following laryngoscopy and intubation, the systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), and heart rate showed a significant increase in the control group B as compared to the treatment group A. In group A, there was attenuation in SBP (one minute = 113.2 ± 14.503, P < 0.001; five minutes = 109.86 ± 8.342, P < 0.001; 10 minutes = 114.24 ± 7.797, P = 0.010), DBP (one minute = 73.72 ± 10.986, P = 0.011; five minutes = 71.62 ± 9.934, P = 0.005; 10 minutes = 76.1 ± 8.006, P = 0.009), MAP (one minute = 86.80 ± 11.86, P = 0.001; five minutes = 84.44 ± 8.97, P = 0.006; 10 minutes = 88.72 ± 7.44, P = 0.018), and heart rate (one minute = 83.34 ± 12.325, P = 0.001; five minutes = 81.56 ± 13.33, P = 0.003; 10 minutes = 80.16 ± 14.086, P = 0.013) following laryngoscopy and intubation. Induction dose of propofol was significantly lower in the dexmedetomidine group (73 ± 19.509, P < 0.001).

Conclusion

Nebulised dexmedetomidine effectively blunts the hemodynamic response to laryngoscopy and intubation and also has a dose sparing effect on the induction dose of propofol.

Intranasal dexmedetomidine premedication in children with recent upper respiratory tract infection undergoing interventional cardiac catheterisation: A randomised controlled trial

BACKGROUND

Recent upper respiratory tract infection (URI) is a risk factor for the occurrence of peri-operative respiratory adverse events (PRAE). This risk may be higher in children with congenital heart disease (CHD), particularly in those undergoing interventional cardiac catheterisation. It is therefore essential to adapt the anaesthetic strategy in these children to prevent from the occurrence of PRAE.

OBJECTIVE

To determine whether intranasal dexmedetomidine (DEX) premedication can reduce the incidence of PRAE in children with recent URI undergoing interventional cardiac catheterisation.

DESIGN

Randomised controlled trial.

SETTING

Single-centre study based at a tertiary care centre in Shanghai, China.

PATIENTS

A total of 134 children with CHD aged 0 to 16 years with recent URI undergoing interventional cardiac catheterisation.

INTERVENTIONS

Children were randomised to receive either intranasal DEX 1.5 μg kg (DEX group) or intranasal saline (Placebo group) 30 to 45 min before anaesthesia induction.

MAIN OUTCOME MEASURES

The incidence of PRAE.

RESULTS

Intranasal DEX significantly reduced the incidence of PRAE (P = 0.001), particularly oxygen desaturation (P = 0.012). Most PRAE were observed during the emergence phase. The incidence of PRAE was comparable among the three types of left-right shunt CHD children in both groups. In children aged less than 3 years, the incidence of PRAE was significantly lower in the DEX group (P = 0.003). In contrast, the incidence of PRAE was comparable between the two groups in children aged at least 3 years. No differences in the incidence of emergence agitation, fever and vomiting between the two groups were noted.

CONCLUSION

Administration of intranasal DEX 1.5 μg kg 30 to 45 min before induction led to a reduction in the incidence of PRAE in children aged less than 3 years with recent URI undergoing interventional cardiac catheterisation.

TRIAL REGISTRATION

chictr.org.cn identifier: ChiCTR-RRC-17012519.

Supplementation With Dexmedetomidine for Transsphenoidal Resection of Pituitary Adenoma: A Meta-Analysis of Randomized Controlled Trials

INTRODUCTION

The effect of dexmedetomidine supplementation on hemodynamic stability for transsphenoidal resection of pituitary adenoma remains controversial. We conduct a systematic review and meta-analysis to explore the influence of dexmedetomidine supplementation on hemodynamic stability for transsphenoidal resection of pituitary adenoma.

METHODS

We have searched PubMed, EMbase, Web of science, EBSCO, and Cochrane library databases through August 2020 for randomized controlled trials assessing the effect of dexmedetomidine supplementation on transsphenoidal resection of pituitary adenoma.

RESULTS

Four randomized controlled trials involving 160 patients were included in the meta-analysis. Overall, compared with the control group for transsphenoidal resection of pituitary adenoma, dexmedetomidine supplementation resulted in significantly reduced mean arterial pressure at 30 minutes [mean difference (MD), -26.62; 95% confidence interval (CI), -36.71 to -16.53; P < 0.00001], heart rate at 30 minutes (MD, -16.50; 95% CI, -32.48 to -0.53; P = 0.04), blood loss (MD, -112.57; 95% CI, -165.12 to -60.01; P < 0.0001), and fentanyl (MD, -154.13; 95% CI, -303.97 to -4.29; P = 0.04), but demonstrated similar incidence of nausea and vomiting (odds ratio, 0.37; 95% CI, 0.13-1.03; P = 0.06), and hypotension (odds ratio, 2.11; 95% CI, 0.49-9.22; P = 0.32).

CONCLUSIONS

Dexmedetomidine supplementation was effective in improving hemodynamic stability for transsphenoidal resection of pituitary adenoma.

Effect of preoperative dexmedetomidine nebulization on the hemodynamic response to laryngoscopy and intubation: a randomized control trial

Background

Dexmedetomidine, an alpha-2 agonist, has been used for attenuation of hemodynamic response to laryngoscopy but not through the nebulized route. We evaluated the effects of preoperative dexmedetomidine nebulization on the hemodynamic response to laryngoscopy and intubation and examined the intraoperative anesthetic-analgesic requirements and recovery outcomes.

Methods

Overall, 120 American Society of Anesthesiologists I & II adult patients (of either gender) undergoing elective surgeries and requiring tracheal intubation, were randomized to receive nebulized dexmedetomidine (1 µg/kg in 3–4 ml of 0.9% saline) or 0.9% saline (3–4 ml), 30 min before anesthesia induction. Heart rate (HR) and non-invasive systolic blood pressure (SBP) were monitored for 10 min following laryngoscopy.

Results

After laryngoscopy, linear mixed effect modelling showed significantly lower trend of increase in HR in the dexmedetomidine group versus saline (P = 0.012); however, there was no difference in the SBP changes between the two groups (P = 0.904). Induction dose of propofol (P < 0.001), intraoperative fentanyl consumption (P = 0.007), and isoflurane requirements (P = 0.013) were significantly lower in the dexmedetomidine group. There was no difference in the 2 h incidence of postoperative nausea and vomiting (PONV) (P = 0.612) or sore-throat (P = 0.741).

Conclusions

Nebulized dexmedetomidine at 1 µg/kg attenuated the increase in HR but not SBP following laryngoscopy and reduced the intraoperative anesthetic and analgesic consumption. There was no effect on early PONV, sore-throat, or increase in incidence of adverse effects. Nebulized dexmedetomidine may represent a favorable alternative to the intravenous route in short duration surgeries.

Comparison of Intranasal Dexmedetomidine and Oral Midazolam for Premedication in Pediatric Dental Patients under General Anesthesia: A Randomised Clinical Trial

The aim of this study was to compare the effects of preoperative intranasal dexmedetomidine and oral midazolam on preoperative sedation and postoperative agitation in pediatric dentistry. A total of 60 children (ASA grade I, aged 3-6 years) scheduled for elective pediatric dental treatment were randomly divided into the dexmedetomidine (DEX) and midazolam (MID) groups. Ramsay sedation score, parental separation anxiety scale, mask acceptance scale, pediatric anesthesia emergence delirium scale, and hemodynamic parameters were recorded. The Ramsay sedation scale and hemodynamic parameters of the children were observed and recorded immediately before administration and 10, 20, and 30 min after administration. A satisfactory mask acceptance scale rate was 93.33% in both MID and DEX groups, and there was no significant difference between the two groups (p > 0.05). The proportions of children that "successfully separated from their parents" were 93.33% (MID) and 96.67% (DEX). No significant difference was found between the two groups (p > 0.05). The incidence of agitation was 20% in the MID group and 0% in the DEX group, and the difference was statistically significant (p < 0.05). Intranasal dexmedetomidine and oral midazolam provided satisfactory sedation. No significant difference between the two groups was found in terms of parental separation anxiety and mask acceptance (p > 0.05). The incidence of postoperative pediatrics emergence delirium was significantly lower in the DEX group (p < 0.05).

Attenuation of haemodynamic responses to laryngoscopy and endotracheal intubation with dexmedetomidine: A comparison between intravenous and intranasal route

Background and Aims:

Haemodynamic changes during endotracheal intubation are major concerns in general anaesthesia This study compared the efficacy of intranasal and intravenous dexmedetomidine (DEX) to attenuate the stress response of laryngoscopy and endotracheal intubation.

Methods:

In this prospective, randomised, double-blinded study, 70 adults were divided into two groups [Group D_IV(n=35) and Group D_IN(n=35)]. D_IV group received intravenous dexmedetomidine (DEX) infusion (0.5 μg/kg) over 40 min and D_IN group received intranasal dexmedetomidine (1 μg/kg) 40 min before induction. The primary objective was the comparison the mean arterial pressure (MAP) between two groups from 40 min before induction at every 10 min intervals till induction of anaesthesia, at the time of intubation, thereafter every 1 min interval till 5 min, at 7 min and 10 min after intubation. The secondary outcomes were comparison of heart rate, systolic and diastolic blood pressure along with sedation and other adverse effects. Statistical analysis was with Statistica 6.0 and Graph Pad prism version 5.

Results:

In both the groups, all the haemodynamic parameters were maintained within (20% of baseline values) throughout the study period. There was no statistically significant difference in MAP between two groups (P>0.05). Preoperative sedation score was significantly higher in the D_IV group than the D_IN group (P = 0.014).

Conclusion:

Like IV DEX, intranasal DEX can also attenuate the haemodynamic stress responses of laryngoscopy and endotracheal intubation without significant differences in MAP between two groups.

Intranasal Low-Dose Dexmedetomidine Reduces Postoperative Opioid Requirement in Patients Undergoing Hip Arthroplasty Under General Anesthesia

BACKGROUND

Patients undergoing total hip arthroplasty (THA) need substantial amount of opioids for postoperative pain management, which necessitates opioid-sparing modalities. Dexmedetomidine is a novel alpha-2-adrenoceptor-activating drug for procedural sedation. In addition to its sedative effect, dexmedetomidine has analgesic and antiemetic effects. We evaluated retrospectively the effect of intraoperatively administered intranasal low-dose dexmedetomidine on postoperative opioid requirement in patients undergoing THA.

METHODS

We included 120 patients with American Society of Anesthesiologists status 1-2, age between 35 and 80 years, and scheduled for unilateral primary THA under general anesthesia with total intravenous anesthesia. Half of the patients received 50 μg of intranasal dexmedetomidine after anesthesia induction, while the rest were treated conventionally. Postoperative opioid requirements were calculated as morphine equivalent doses for both groups. The impact of intranasal dexmedetomidine on postoperative hemodynamics and length of stay was evaluated.

RESULTS

The cumulative postoperative opioid requirement was significantly reduced in the dexmedetomidine group compared with the control group (26.3 mg, 95% confidence interval 15.6-36.4, P < .001). The cumulative dose was significantly different between the groups already at 12, 24, and 36 h postoperatively (P = .01; P = .001; P < .001, respectively). Dexmedetomidine group had lower mean arterial pressure in the postanesthesia care unit compared with the control group (P = .01). There was no difference in the postanesthesia care unit stay or postoperative length of stay between the two groups (P = .47; P = .10, respectively).

CONCLUSION

Compared with the control group, intraoperative use of intranasal low-dose dexmedetomidine decreases opioid consumption and sympathetic response during acute postoperative period in patients undergoing THA.

Anesthesia for functional endoscopic sinus surgery

PURPOSE OF REVIEW

The present article summarizes anesthetic techniques used during functional endoscopic sinus surgery to decrease bleeding and aid in creating a clear surgical field. The applicable physiology behind these anesthetic techniques is reviewed with emphasis on the effect on bleeding and the surgical field. Deliberate hypotension, reverse Trendelenburg positioning, regional anesthesia, and cerebral monitoring are discussed.

RECENT FINDINGS

There are mixed data as to whether traditional inhalation anesthesia or total intravenous anesthesia is superior with respect to better surgical fields and decreased blood loss. A review of the literature tends to favor total intravenous anesthesia. Cerebral oximetry and transcranial Doppler ultrasound are emerging techniques to monitor cerebral perfusion during deliberate hypotension.

SUMMARY

Total intravenous anesthesia using propofol and remifentanil is the current favored technique for producing deliberate hypotension during endoscopic sinus surgery due to its hemodynamic stability and smooth rapid emergence.

Effect of intratracheal dexmedetomidine administration on recovery from general anaesthesia after gynaecological laparoscopic surgery: a randomised double-blinded study

OBJECTIVES

To examine the efficacy of intratracheal dexmedetomidine (Dex) injection for the prevention of the laryngeal response on emergence from general anaesthesia following gynaecological laparoscopic surgery.

DESIGN

Prospective, randomised, double-blinded, controlled trial.

SETTING

A general hospital, Guangdong Province, China.

PARTICIPANTS

All patients who underwent elective laparoscopic gynaecological surgery, aged 18-60 years old, 40-80 kg in weight, American Society of Anesthesiologists class I-II were eligible. Patients were excluded if they had respiratory disease, heart disorders which might represent risk factors of potential complications of Dex such as bradycardia, heart block, coronary heart disease, uncontrolled hypertension or the long-term use of sedative drugs.

INTERVENTION

Patients were randomly allocated to either receive intratracheal Dex (DT), intravenous Dex (DV) or intravenous saline (CON, n=30, respectively). In the DT and DV groups, Dex (0.5 µg/kg) was diluted and mixed in 1 or 20 mL of saline, respectively, and injected via the intratracheal or intravenous route 30 min before the completion of the surgery.

OUTCOME MEASURES

The primary outcome was the coughing extent among the three groups. Secondary outcomes included awareness time, extubation time, postoperative visual analogue scale and Steward recovery score.

RESULTS

Compared with the CON group, the extent of coughing was significantly reduced in both the DV group and the DT group. Furthermore, the mean time to awareness (13.4 (4.3) vs 8.8 (2.9), p<0.001) and the extubation time (14.3 (4.3) vs 8.4 (3.6), p<0.001) were reduced in the DT group. Patients in the DT group also experienced better early recovery quality and less pain than those in the CON group. Furthermore, intratracheal Dex administration contributed to improved stability in haemodynamics with no significant side effects.

CONCLUSIONS

Intratracheal Dex administration may avoid untoward laryngeal responses for patients emerging from general anaesthesia after gynaecological laparoscopy.

TRIAL REGISTRATION NUMBER

ChiCTR-IOR-15007611.

Dexmedetomidine for refractory adrenergic crisis in familial dysautonomia

OBJECTIVE

Adrenergic crises are a cardinal feature of familial dysautonomia (FD). Traditionally, adrenergic crises have been treated with the sympatholytic agent clonidine or with benzodiazepines, which can cause excessive sedation and respiratory depression. Dexmedetomidine is a centrally-acting α ₂-adrenergic agonist with greater selectivity and shorter half-life than clonidine. We evaluated the preliminary effectiveness and safety of intravenous dexmedetomidine in the treatment of refractory adrenergic crisis in patients with FD.

METHODS

Retrospective chart review of patients with genetically confirmed FD who received intravenous dexmedetomidine for refractory adrenergic crises. The primary outcome was preliminary effectiveness of dexmedetomidine defined as change in blood pressure (BP) and heart rate (HR) 1 h after the initiation of dexmedetomidine. Secondary outcomes included incidence of adverse events related to dexmedetomidine, hospital and intensive care unit (ICU) length of stay, and hemodynamic parameters 12 h after dexmedetomidine cessation.

RESULTS

Nine patients over 14 admissions were included in the final analysis. At 1 h after the initiation of dexmedetomidine, systolic BP decreased from 160 ± 7 to 122 ± 7 mmHg (p = 0.0005), diastolic BP decreased from 103 ± 6 to 65 ± 8 (p = 0.0003), and HR decreased from 112 ± 4 to 100 ± 5 bpm (p = 0.0047). The median total adverse events during dexmedetomidine infusion was 1 per admission. Median hospital length of stay was 9 days [interquartile range (IQR) 3-11 days] and median ICU length of stay was 7 days (IQR 3-11 days).

CONCLUSIONS

Intravenous dexmedetomidine is safe in patients with FD and appears to be effective to treat refractory adrenergic crisis. Dexmedetomidine may be considered in FD patients who do not respond to conventional clonidine and benzodiazepine pharmacotherapy.