Comparison between dexmedetomidine and fentanyl on intubation conditions during awake fiberoptic bronchoscopy: A randomized double-blind prospective study

Comparative evaluation of nebulized versus intravenous dexmedetomidine on intubating conditions during awake fiberoptic nasotracheal intubation

BACKGROUND

There is a search for an ideal agent to facilitate awake fiberoptic intubation (AFOI). Dexmedetomidine is a selective α2 agonist which can be administered through intravenous, intramuscular, buccal, intranasal & inhalational routes. It provides good intubation conditions without oxygen desaturation but may cause hypotension and bradycardia when administered intravenously. Hence, alternative routes of administering dexmedetomidine which may improve its safety profile are worth exploring.

METHODS

In this randomised, controlled, double-blind trial, 46 ASA I/II adult participants scheduled for elective ENT surgery were randomly allocated to Group ND (Nebulised Dexmedetomidine) (n = 23) to receive nebulisation with dexmedetomidine 1μg.kg-1 and Group ID (Intravenous Dexmedetomidine) (n = 23) to receive intravenous dexmedetomidine 1μg.kg-1 before AFOI. All the patients received injection midazolam 1 mg i.v. as premedication before anaesthesia was initiated. The primary outcome was the cough score. The secondary outcomes were the RSS, SAYGO boluses, post-intubation score, hemodynamic parameters, recall of the procedure, patient satisfaction score and any side effects.

RESULTS

The cough score was significantly lower in nebulized group (2.43 ± 0.992 vs 3.52 ± 1.082) with p = 0.001. RSS(3.30 ± 0.926 vs 4.22 ± 1.126; p = 0.004), number of SAYGO boluses required (2.74 ± 0.864 vs 3.57 ± 1.161; p = 0.009) & the post intubation score (1.48 ± 0.593 vs 2.17 ± 0.778; p = 0.001) were also significantly lower in nebulized group.

CONCLUSIONS

Nebulisation with dexmedetomidine results in desirable degree of sedation and better tolerance of the procedure with adequate attenuation of the haemodynamic responses to intubation.

Effect of different doses of dexmedetomidine as an adjuvant to lignocaine nebulization: A comparative study during awake flexible fiberoptic bronchoscopy

Background and Aims

Mild to moderate sedation during bronchoscopy is essential for patient safety, comfort during and after the procedure, and to facilitate the performance of the bronchoscopist. Dexmedetomidine is a highly selective, centrally acting α-2 agonist used to provide conscious sedation during various procedures. The aim of this study was to compare the efficacy of three different doses of dexmedetomidine nebulization as an adjuvant to lignocaine during bronchoscopy.

Material and Methods

Ninety American Society of Anesthesiologists physical status I/II patients, aged from 18 to 60 years, scheduled for an elective bronchoscopy, were recruited. They were divided into three groups: 30 patients in each group. Group I: The patient was nebulized with a mixture of 4 ml of 4% lignocaine and dexmedetomidine 0.5 μg/kg. Group II: The patient was nebulized with a mixture of 4% lignocaine, 4 ml, and dexmedetomidine, 1 μg/kg. Group III: The patient was nebulized with 4% lignocaine 4 ml and dexmedetomidine 1.5 μg/kg.

Results

The mean cough score was (1.17 ± 0.37), (1.40 ± 0.49), and (1.70 ± 0.75) in group III, group II, and group I, respectively. A significant difference was found between the groups. Patients were more comfortable with a statistically significant difference in the comfort score in group III as compared to group II and group I.

Conclusion

Dexmedetomidine nebulization in a dose of 1.5 μg/kg (compared to 1 μg/kg or 0.5 μg/kg) as an adjuvant to lignocaine, provides better bronchoscopy conditions and patient satisfaction.

A comparative examination of morphine and fentanyl: unravelling the differential impacts on breathing and airway stability

This study provides an in-depth analysis of the distinct consequences of the opioid drugs morphine and fentanyl during opioid-induced respiratory depression (OIRD). We explored the physiological implications of both drugs on ventilation and airway patency in anaesthetized mice. Our results revealed a similar reduction in respiratory frequency with equivalent scaled dosages of fentanyl and morphine, though the onset of suppression was more rapid with fentanyl. Additionally, fentanyl resulted in transient airflow obstructions during the inspiratory cycle, which were absent following morphine administration. Notably, these fentanyl-specific obstructions were eliminated with tracheostomy, implicating the upper airways as a major factor contributing to fentanyl-induced respiratory depression. We further demonstrate that bronchodilators salbutamol and adrenaline effectively reversed these obstructions, highlighting the bronchi's contribution to fentanyl-induced airflow obstruction. Our study also uncovered a significant reduction in sighs during OIRD, which were eliminated by fentanyl and markedly reduced by morphine. Finally, we found that fentanyl-exposed mice had reduced survival under hypoxic conditions compared to mice given morphine, demonstrating that fentanyl becomes more lethal in the context of hypoxaemia. Our findings shed light on the distinct and profound impacts of these opioids on respiration and airway stability and lay the foundation for improved opioid use guidelines and more effective OIRD prevention strategies. KEY POINTS: Both morphine and fentanyl significantly suppressed respiratory frequency, but the onset of suppression was faster with fentanyl. Also, while both drugs increased tidal volume, this effect was more pronounced with fentanyl. Fentanyl administration resulted in transient obstructions during the inspiratory phase, suggesting its unique impact on airway stability. This obstruction was not observed with morphine. The fentanyl-induced obstructions were reversed by administering bronchodilators such as salbutamol and adrenaline. This suggests a possible therapeutic strategy for mitigating the adverse airway effects of fentanyl. Both drugs reduced the frequency of physiological sighs, a key mechanism to prevent alveolar collapse. However, fentanyl administration led to a complete cessation of sighs, while morphine only reduced their occurrence. Fentanyl-treated mice showed a significantly reduced ability to survive under hypoxic conditions compared to those administered morphine. This indicates that the impacts of hypoxaemia during opioid-induced respiratory depression can vary based on the opioid used.

Comparison of dexmedetomidine alone with dexmedetomidine and fentanyl during awake fiberoptic intubation in patients with difficult airway: a randomized clinical trial

Background

Awake fiberoptic intubation (AFOI) is the procedure of choice for securing the airway in patients with a difficult airway when undergoing surgeries under general anesthesia. An ideal drug would not only provide conscious sedation but also maintain spontaneous ventilation, smooth intubation conditions, and stable hemodynamics. We compared the effects of dexmedetomidine alone and dexmedetomidine in combination with fentanyl at a dose lower than the standard dose for achieving conscious sedation during AFOI in difficult airway patients undergoing oral cancer and dental surgeries.

Methods

We included 68 adult patients undergoing AFOI. The patients were randomized in two groups, wherein Group D received intravenous dexmedetomidine 1 µg/kg and Group DF received dexmedetomidine 0.5 µg/kg and fentanyl 1 µg/kg. The outcomes measured were airway obstruction score, intubation scores, fiberoptic intubation comfort score, sedation score, and hemodynamic variables.

Results

Low-dose dexmedetomidine with fentanyl showed similar results as those with the standard dose of dexmedetomidine in terms of airway obstruction, vocal cord movement, degree of cough, degree of limb movements, and intubation comfort. However, the sedation achieved and incidence of hypotension and bradycardia were higher in Group D than in Group DF.

Conclusions

A low dose of dexmedetomidine–fentanyl provides satisfactory intubation conditions as those with a standard dose of dexmedetomidine in AFOI, thereby avoiding bradycardia, hypotension, and sedation.

Fentanyl versus nalbuphine for intubating conditions during awake fiberoptic bronchoscopy: A randomized double-blind comparative study

Background and Aims:

Patient cooperation, sedation, anxiolysis, and topicalization are important prerequisites for the successful and safe conduct of awake intubation. Because of the pharmacological properties, opioids can facilitate this process. Fentanyl is an opioid agonist and nalbuphine is an agonist-antagonist. This study aims to compare these two opioids for their effect on sedation and intubating conditions during awake fiberoptic intubation.

Material and Methods:

This randomized double-blind controlled study was conducted on 62 ASA I/II patients of either sex between the age of 20 and 60 years, weight between 40 and 80 kg, with MP class I/II airways requiring general anesthesia with endotracheal intubation. All patients received standard airway topicalization and nebulization. Patients were randomly allocated to one of the two groups according to a computer-generated random number table. Group F (n = 31) received fentanyl 2 μg/kg i.v. and group N (n = 31) received nalbuphine 0.2 mg/kg i.v. over 10 min before intubation. Fiberoptic intubation was attempted and lignocaine spray and propofol boluses were administered as and when required. Hemodynamic responses and intubating conditions were recorded. Repeated measure ANOVA, McNemar test, and Chi-square test or Fischer's exact test were used for data analysis. A P < 0.05 was considered significant.

Results:

Cough score (P = 0.458), post-intubation score (P = 1.000), and sedation score (P = 1.000) were comparable among the two groups. Hemodynamic responses and propofol and lignocaine requirements were also comparable.

Conclusion:

Both fentanyl and nalbuphine provide comparable intubating conditions when used before awake fiberoptic intubation with minimal adverse effects on hemodynamic profile.

Dexmedetomidine combined with midazolam infusion guided by bispectral index during bronchoscopy

BACKGROUND

Conscious sedation guided by bispectral index (BIS) during bronchoscopy has been proved to be a feasible approach. This study aimed to investigate the safety and efficacy of dexmedetomidine combined with midazolam for undergoing conscious sedation during bronchoscopy.

METHODS

The trial was registered prior to patient enrollment at the Chinese Clinical Trial Registry. Patients were randomized into DEX group (dexmedetomidine combined with midazolam) and FEN group (fentanyl combined with midazolam). Bronchoscopy was performed under awake sedation titrated to a BIS level of 60-80. The primary endpoint was the incidence of hypoxia, the secondary endpoint was the incidence of bradycardia and hypotension, effect of sedation including satisfaction degree (VAS) of the operators and patients and patients' willingness to undergo bronchoscopy again.

RESULTS

A total of 222 cases in DEX group and 211 cases in FEN group completed the study. The incidence of hypoxia and tachycardia in DEX group was lower than that in FEN group (8.1% vs 14.7%, 10.4% vs 19.0%, p < 0.05), and the incidence of hypotension and bradycardia in DEX group was higher than that in FEN group (6.8% vs 0, 15.3% vs 8.1%, p < 0.05). Midazolam dosage was significantly lower in the DEX group than in the FEN group, and the duration of surgery was significantly longer in the DEX group. The differences in intraoperative discomfort of VAS score, satisfaction VAS score, and willingness rate to undergo bronchoscopy again were not statistically significant between the two groups. In addition, the proportion of "procedural interference by patient movement" in DEX group was higher than that in FEN group.

CONCLUSIONS

The conscious sedation regimen of dexmedetomidine combined with midazolam monitored by BIS is considered to be safe and effective during bronchoscopy. The occurrence of hypoxia and tachycardia was less, and the fluctuation of blood pressure and heart rate was mild, but the proportion of bradycardia in dexmedetomidine group was higher than that in fentanyl combined with midazolam group.

Comparison between Intravenous Dexmedetomidine and Spray as you Go with 4% Lignocaine Versus Intravenous Fentanyl and Transtracheal Injection of 4% Lignocaine for Awake Nasotracheal Intubation with Flexible Vedioscope - A Randomized Single-Blind Prospective Study

Background:

Awake fiber-optic bronchoscopy-guided intubation is the method of choice in difficult airway which requires effective airway anesthesia to ensure patient comfort and acceptance.

Aims:

This study was conducted to assess the quality of airway anesthesia, patient comfort during intubation, and postoperative satisfaction of patients.

Settings:

Patients posted for surgeries under general anesthesia with Mallampati Grade I and II in a medical college. Patients were followed in the operation theater and postoperative ward.

Study Design:

This was a prospective randomized single-blind study.

Materials and Methods:

Group D received intravenous (i.v.) dexmedetomidine 1 μg.kg⁻¹ i.v. over 10 min and 3 ml of 4% lignocaine spray as you go (SAYGo). Group F received i.v. fentanyl 2 μg.kg⁻¹ over 10 min and transtracheal injection 3 ml of 4% lignocaine. Parameters assessed were endoscopic time, intubating condition, vocal cord position, cough severity, comfort during intubation, postoperative patient satisfaction, and any adverse effects such as sore throat, hoarseness, unpleasant memories, and hemodynamic response during intubation.

Statistical Analysis:

Independent Student's t-test, Mann–Whitney, Chi-squared test, or Fisher's exact test were used. P ≤ 0.05 was considered statistically significant.

Results:

Intubating conditions, vocal cord position, cough severity, comfort during intubation, and postoperative patient satisfaction were statistically significant (P ≤ 0.05) in favor of Group D though endoscopic time was longer.

Conclusion:

IV dexmedetomidine with SAYGo is effective than IV fentanyl with transtracheal block for awake fiber-optic videoscopic intubation in terms of intubating conditions, vocal cord position, cough severity, comfort during intubation, and postoperative satisfaction of patients with significant attenuation of postintubation hemodynamic response and better preservation of respiration though endoscopic time is more.

A Randomized Controlled Study Comparing Dexmedetomidine-Midazolam with Fentanyl-Midazolam for Sedation during awake Fiberoptic Intubation in Anticipated Difficult Airway

Background:

Awake fibreoptic nasotracheal intubation is an effective technique for the management of patients with difficult airways. Adequate sedation with effective topicalization of the airway is important to overcome discomfort and achieve intubation successfully.

Aim and Objectives:

Our aim was to compare the effectiveness of dexmedetomidine-midazolam with fentanyl-midazolam infusion for providing conscious sedation during fibreoptic intubation in patients with anticipated difficult airway under topical anaesthesia.

Materials and Methods:

Thirty adult patients of ASA physical status classification I and II with anticipated difficult airway and planned for elective awake nasal fibreoptic intubation under conscious sedation were randomly allocated into two groups. Dexmedetomidine 1 μg.kg-1 diluted in 50 ml saline was infused in Group DM over 10 min and Fentanyl 2 μg.kg-1 diluted in 50 ml saline was infused in Group FM over 10 min. Topicalization of the airway was done in all patients. All patients were assessed for sedation score, ease of endotracheal tube placement, patient comfort and cooperation, tolerance to endotracheal tube, any adverse events and recall of procedure.

Results:

The score of the modified OAA/S was comparable between the groups (P > 0.05). Quality of AFOI was comparable in both groups (P > 0.05). The intubation time and first EtCO2 were significantly lower in dexmedetomidine group (P <0.05). Group DM also showed better hemodynamics and less episodes of desaturation than Group FM.

Conclusion:

Fentanyl-midazolam and dexmedetomidine-midazolam are both effective for awake fiberoptic intubation under topical anesthesia. Dexmedetomidine allows better endurance and more stable hemodynamics.

The role of dexmedetomidine in neurosurgery

Dexmedetomidine can be used for sedation and analgesia and has been approved for this use by the European Medicines Agency since 2017. It causes an arousable state of sedation, which is beneficial during neurosurgical procedures that require the patient to cooperate with neurological tests (i.e. tumor surgery or implantation of deep brain stimulators). During procedures where monitoring of somatosensory evoked potentials and/or motor evoked potentials is required, dexmedetomidine can be used as an adjunct to general anesthesia with GABAergic drugs to decrease the dose of the latter when these drugs impair the monitoring signals. The use of dexmedetomidine has also been associated with neuroprotective effects and a decreased incidence of delirium, but studies confirming these effects in the peri-operative (neuro-)surgical setting are lacking. Although dexmedetomidine does not cause respiratory depression, its hemodynamic effects are complex and careful patient selection, choice of dose, and monitoring must be performed.

A Synopsis of Contemporary Anesthesia Airway Management

New airway equipment has recently become available that has reduced morbidity and mortality. However, airway disasters still occur. This article discusses the prudent escalation of the use of advanced airway equipment to prevent these disasters. We illustrate when and how to use a gum elastic bougie and a video-laryngoscope (VL). We also strongly recommend the combined use of the VL together with a flexible intubation scope (FIS) for both asleep and awake intubation when dealing with a genuinely difficult airway. Blind intubations should no longer be performed today. When an airway has been recognized as difficult it is the safest to aim for an awake or at least a spontaneously breathing intubation if circumstances do not allow for an awake intubation. Emergency cricothyroidotomy needs to be prepared for so that it can be executed rapidly in case the attempted awake intubation leads to complete airway obstruction.

Is It Time for an Expanded Role of Dexmedetomidine in Contemporary Anesthesia Practice? - A Clinician's Perspective

Since its approval by US Food and Drug Administration in 1999 the clinical use of dexmedetomidine has been gaining in popularity. The indications and clinical applications of this drug have been expanded significantly. In this paper we reviewed its pharmacokinetics, pharmacodynamics, mechanisms of action and mainly focused on its clinical uses and outcomes. Common clinical uses of dexmedetomidine include pre-operative anxiolysis, heart rate control during intubation, treatment of bronchospasm, prevention of laryngospasm and avoiding opioid-induced post-operative respiratory depression and nausea and vomiting. Avoiding opioid induced respiratory depression has been especially beneficial in patients with sleep apnea syndrome. Other problems that can be prevented with dexmedetomidine are tachydysrhythmias, myocardial ischemia, delirium and acute kidney injury. Dexmedetomidine is an excellent sedative drug for intubated patients and it greatly facilitates neurological evaluation. It has been used successfully as a patient-controlled anesthesia drug and to prevent shivering. It is also used as an adjuvant to local anesthetics. It has been suggested that dexmedetomidine is a drug that has many beneficial effects and should be used more frequently by anesthesia care providers to prevent common problems in the peri-operative period. With judicious titration to effect during the intravenous administration of this drug the occurrence of side effects can be minimized. It is very likely that this drug will ascend to take a much more prominent role in future anesthesia practice.

Comparison between lignocaine nebulization and airway nerve block for awake fiberoptic bronchoscopy-guided nasotracheal intubation: a single-blind randomized prospective study

BACKGROUND

The preferred management strategy for difficult airways is awake fiberoptic bronchoscopy-guided intubation, which requires effective airway anesthesia to ensure patient comfort and acceptance. This randomized single-blind prospective study was conducted to compare lignocaine nebulization and airway nerve block for airway anesthesia prior to awake fiberoptic bronchoscopy-guided intubation.

METHODS

Sixty adult patients scheduled for surgical procedures under general anesthesia were randomly allocated to two groups. Group N received jet nebulization (10 ml of 4% lignocaine) and Group B received bilateral superior laryngeal and transtracheal recurrent laryngeal nerve blocks (each with 2 ml of 2% lignocaine) followed by fiberoptic bronchoscopy-guided nasotracheal intubation. All patients received procedural sedation with dexmedetomidine. The intubation time, intubating conditions, vocal cord position, cough severity, and degree of patient satisfaction were recorded. Student's t test was used to analyze parametric data, while the Mann-Whitney U test was applied to non-parametric data and Fisher's test to categorical data. P values < 0.05 were considered statistically significant.

RESULTS

The time taken for intubation was significantly shorter in Group B [115.2 (14.7) s compared with Group N [214.0 (22.2) s] (P = 0.029). The intubating conditions and degree of patient comfort were better in Group B compared with Group N. Although all patients were successfully intubated, patient satisfaction was higher in Group B.

CONCLUSIONS

Airway nerve blocks are preferable to lignocaine nebulization as they provide superior-quality airway anesthesia. However, nebulization may be a suitable alternative when a nerve block is not feasible.

Hemodynamic Responses and Safety of Sedation Following Premedication with Dexmedetomidine and Fentanyl during Fiberoptic-assisted Intubation in Patients with Predicted Difficult Airway

Background:

Awake fiberoptic intubation (AFOI) is the gold standard for the management of predicted difficult airway, and inappropriate sedation is a major cause leading to its failure.

Aims:

The primary objective was to compare the heart rate (HR) changes that accompany AFOI following sedation with dexmedetomidine and fentanyl. Secondary objectives included comparison of changes in blood pressure, patient comfort, ease of intubation, and degree of sedation.

Settings and Designs:

This prospective double-blinded randomized study was conducted in a tertiary care institution.

Subjects and Methods:

Forty patients with anticipated difficult airway requiring AFOI were included in the study. Group A received dexmedetomidine 1 μg/kg whereas Group B received fentanyl 2 μg/kg. After topical anesthesia of the airway, AFOI was performed.

Statistical Analysis Used:

Fisher's exact test, independent two-sample t-test, and Mann–Whitney U-test were used as applicable.

Results:

The hemodynamic parameters were comparable in both the groups except at 1 min postintubation when fentanyl group had significantly higher HR. There were lower alertness and muscle tone scores in dexmedetomidine group. Total comfort score was significantly higher in fentanyl group. Though more patients in dexmedetomidine group showed that no reaction to intubation and more patients in fentanyl had slight grimacing, the difference was insignificant. The ease of intubation was similar in both the groups.

Conclusion:

Though dexmedetomidine1 μg/kg and fentanyl 2 μg/kg premedication results in comparable hemodynamics and ease of intubation, in view of enhanced patient comfort, dexmedetomidine premedication is advantageous in patients with anticipated difficult airway undergoing AFOI.

Correlation of bispectral index and Richmond agitation sedation scale for evaluating sedation depth: a retrospective study

Background

This study aims to verify the correlation of bispectral index (BIS) and Richmond agitation sedation scale (RASS) for evaluating these and explore possibility of replacing RASS with BIS.

Methods

This retrospective cohort study consisted of 74 patients who were collected from the third Intensive Care Unit (ICU) ward of XXX Hospital between May 2012 and June 2015 in this retrospective study. Sedation levels were evaluated using the 10-grade RASS and were continuously monitored with a BIS monitor during the procedure every 5 minutes. BIS values and RASS scores were recorded.

Results

Patients were divided into dexmedetomidine (n=31) and midazolam (n=43) groups, and 342 paired data were collected. A statistically significant correlation existed between BIS values and RASS scores either in all patients undergoing flexible fiberoptic bronchoscopy (FFB) or in dexmedetomidine and midazolam groups at different time points. Correlation coefficient was higher in midazolam group compared with dexmedetomidine group at different time points (P<0.05).

Conclusions

A correlation was observed between BIS and RASS for evaluating depth of sedation in ICU patients undergoing FFB (P<0.05). Study results indicated that BIS monitoring is a meaningful tool, which can be applied as an adjunctive and alternative method to assess sedation, especially for high-risk patients who are prone to be under- or over-sedation.

Intravenous dexmedetomidine as an adjunct to subarachnoid block: A simple effective method of better perioperative efficacy

BACKGROUND AND AIM

Dexmedetomidine (D) is a α2 agonist, has anesthetic and analgesic-sparing property. The objective of this study was to evaluate the effect of intravenous (I.V.) dexmedetomidine on the duration of sensory and motor block, postoperative analgesia, the level of sedation and side effect.

MATERIAL AND METHODS

Sixty patients were randomly divided into two groups of thirty each. Group D received dexmedetomidine infusion @1 mcg/kg over 10 min and then @ 0.6 mcg/kg/h for rest of duration during surgery, Group C (control) received a similar volume of normal saline infusion before spinal anesthesia with 3 ml of bupivacaine 0.5%. Time of onset and regression time for sensory and motor blockade, the maximum upper level of sensory blockade, duration of postoperative analgesia, Ramsay sedation score and hemodynamic parameters were recorded. Intraoperative bradycardia and atropine requirement along with other side effect were also recorded.

RESULTS

The duration of sensorimotor block was significantly longer in D Group (341.7 ± 20.8 min for sensory block and 278.0 ± 11.0 min for motor block) as compared to control group (329.5 ± 22.1 min for sensory block and 250.0 ± 14.8 min for motor block), which was statistically significant (P < 0.05). The mean time for two dermatomal regression of sensory blockade was significantly prolonged in dexmedetomidine group (115.5 ± 8.7 min) compared to control group (95.8 ± 11.4) (P < 0.001). Intraoperative Ramsay sedation scores were significantly higher in D Group (mean - 3.4 ± 0.7, range - 2-4) as compared to C Group (mean - 2.9 ± 0.3, range - 2-4) (P < 0.001). 26.7% (8/30) cases had bradycardia that required atropine as compared to control group (2/30), and none of the patients in the dexmedetomidine group had postoperative shivering as compared to 10% in control group (P = 0.056). Statistical analysis was performed with statistical package for the social science version-20 using analysis of variance/Chi-square test/unpaired t-test, and P < 0.05 was considered statistically significant.

CONCLUSION

I.V. dexmedetomidine significantly prolongs the duration of sensory and motor block of bupivacaine spinal anesthesia. Dexmedetomidine provides an excellent sedation during surgery.

Effect of dexmedetomidine and midazolam for flexible fiberoptic bronchoscopy in intensive care unit patients: A retrospective study

This study aimed to investigate the clinical effectiveness of dexmedetomidine and midazolam for sedation of intensive care unit (ICU) patients requiring flexible fiberoptic bronchoscopy (FFB).This retrospective cohort study included 148 patients from the third ICU ward of the Second Affiliated Hospital of Harbin Medical University (Harbin, China) who received simultaneous invasive mechanical ventilation and FFB between March 2012 and December 2014. Patients were divided into dexmedetomidine (n  =  72) and midazolam (n  =  76) groups according to sedative mode. The sedative effects, incidence of adverse events, and bronchoscopist satisfaction scores were compared between groups.During FFB, total sedation time and total time of FFB were significantly shorter in the midazolam group (P < .001, respectively), with a lower percentage of these patients requiring propofol for remedial sedation (P < .001). The incidence of FFB-related adverse events (including bronchospasm, cough, and decreased oxygen saturation) was significantly higher in dexmedetomidine group compared with midazolam group (P  =  .007, .014 and .008, respectively). However, the incidence of other adverse events was not significantly different between groups. In addition, bronchoscopist satisfaction scores were significantly higher in the midazolam compared with dexmedetomidine group (7.72 ± 1.65 vs 7.08 ± 1.77; P  =  .030).For sedation of ICU patients during FFB, combination of midazolam and dexmedetomidine demonstrated an enhanced sedative effect, lower incidence of adverse events, and higher bronchoscopist satisfaction score compared with dexmedetomidine alone, thus represents a suitable alternative sedative for FFB patients.

Evaluation of different doses of dexmedetomidine alone versus the combination of dexmedetomidine and fentanyl in sedation during awake fiberoptic intubation in oral cancer surgery patients: A prospective, randomized, double-blind clinical trial

BACKGROUND

Awake fiberoptic intubation (AFOI) is one of the principal techniques in the management of difficult airway in oral cancer surgery. We hypothesized that the addition of a small dose of fentanyl could improve the sedative criteria of dexmedetomidine during AFOI technique, without the need to increase the dose of dexmedetomidine which may be associated with airway compromise.

PATIENTS AND METHODS

One hundred and fifty American Society of Anesthesiologists physical status 1 and 2 patients planned for AFOI for oral cancer surgery patients were allocated into three groups (fifty patients each). Group D1: Received an infusion of 1 μcg/kg dexmedetomidine diluted in 50 ml saline over 20 min. Group D2: Received an infusion of 2 μcg/kg dexmedetomidine diluted in 50 ml saline over 20 min. Group DF: Received an infusion of 1 μcg/kg dexmedetomidine added to 1 μcg/kg fentanyl diluted in 50 ml saline over 20 min. AFOI was done by topical anesthesia and with the same technique in all patients. All patients were assessed for: airway obstruction, intubation scores (vocal cord movement, coughing, and limb movement), fiberoptic intubation scores, and hemodynamic variables. Any episode of bradycardia or hypoxia was recorded and managed.

RESULTS

Group D2 showed more incidence of airway obstruction than the other two groups. Limb movement scores were more in Group D1 compared to the other two groups. All groups were comparable as regard fiberoptic intubation scores, coughing, and vocal cord opening scores.

CONCLUSION

Adding a low dose of fentanyl (1 μcg/kg) to a low dose of dexmedetomidine can prevent the risk of airway obstruction associated with increasing the dose of dexmedetomidine while achieving the same favorable intubation scores.

Efficacy of intravenous dexmedetomidine on patient's satisfaction, comfort and sedation during awake fibre-optic intubation in patients with cervical spondylotic myelopathy posted for elective cervical fixation

Background and Aims:

Various anaesthetic drugs, in addition to airway block, are used for producing favourable intubation conditions during awake fibre-optic intubation (AFOI), but most of them cause respiratory depression and hypoxaemia. The aim of this study was to evaluate the efficacy of intravenous (IV) dexmedetomidine (DEX) on sedation, patient comfort and cardiovascular responses during AFOI in patients with cervical spondylotic myelopathy (CSM).

Methods:

This randomised, placebo-controlled, double-blinded, prospective study was conducted on 56 adult patients with cervical spondylotic myelopathy (CSM) undergoing elective cervical fixation, who were randomly allocated into two groups - Group D and Group C. Group D patients received DEX infusion at a rate of 1 μg/kg for the first 10 min followed by 0.5 μg/kg/h and Group C received 0.9% normal saline infusion in the same manner. Airway blocks with lignocaine were given to all patients before undergoing AFOI. Patient's alertness, sedation and cardiorespiratory changes during the procedure were assessed by the Observer Assessment Awareness and Sedation (OAA/S) scale. On the 1^st post-operative day, patient's' comfort during AFOI was assessed by visual analogue scale (VAS).

Results:

Patients of Group D had an acceptable level of sedation (OAA/S score: 20 to 17 with greater comfort and satisfaction (VAS: 40–60), compared to control group (VAS: 50–90, P < 0.001.). Moreover, haemodynamic parameters were less significantly altered in the DEX group during AFOI.

Conclusions:

IV DEX infusion during AFOI improves patient's tolerances with an acceptable level of sedation without significant haemodynamic instability and respiratory depression.

Evaluation of Effectiveness of Dexmedetomidine and Fentanyl-midazolam Combination on Sedation and Safety during Awake Fiberoptic Intubation: A Randomized Comparative Study

Background

Awake fiberoptic intubation (AFOI) is a recommended technique for anticipated difficult airway. An ideal regime should provide patient comfort, cooperation, amnesia, hemodynamic stability, and blunt airway reflexes and maintain a patent airway with spontaneous ventilation. The aim of our study was to compare intubation conditions between dexmedetomidine and fentanyl-midazolam combination during AFOI.

Methods

This prospective, randomized study was conducted on a total of sixty patients of the American Society of Anesthesiologists physical status I and II of either sex, in the age group of 18-60 years having predicted difficult intubation undergoing elective surgeries and the patients were allocated to two groups of thirty patients each. After premedication and topicalization of airways, dexmedetomidine group (Group I, n = 30) received dexmedetomidine 1 μg/kg over 10 min and midazolam-fentanyl group (Group II, n = 30) received fentanyl 2 μg/kg plus midazolam 0.02 mg/kg over 10 min. Adequacy of intubation condition was evaluated by cough score and postintubation score. Incidence of desaturation, hemodynamic changes, and sedation using Ramsay sedation scale were noted and compared between two groups.

Results

The demographic characteristics were comparable in the two groups (P > 0.05). The mean Ramsay sedation score in Group I was 3.13 ± 0.937 and Group II was 3.16 ± 0.949, and the comparison between two groups was statistically insignificant (P = 0.891). Cough scores and postintubation scores were favorable in dexmedetomidine group than midazolam-fentanyl group and were statistically significant with P < 0.001 and 0.0001, respectively. Group I also showed better hemodynamics and less episodes of desaturation than Group II.

Conclusions

Dexmedetomidine is more effective than midazolam-fentanyl during AFOI, as it provides better intubation condition, hemodynamic stability, and preservation of airway and spontaneous ventilation.

Awake orotracheal fibre-optic intubation: Comparison of two different doses of dexmedetomidine on intubation conditions in patients undergoing cervical spine surgery

Background and Aims

Awake fibre-optic intubation (AFOI) is an integral part of anaesthetic management of difficult airways. Conscious sedation is essential to assist AFOI. This study compared two different doses of dexmedetomidine in combination with topical spray and airway blocks for awake orotracheal fibre-optic intubation in patients undergoing elective cervical spine surgery with rigid cervical collar in situ.

Methods

A randomized, prospective, comparative study design was conducted in sixty patients divided into two groups: Group (L) (n = 30) patients received low dose of dexmedetomidine (0.5 μg/kg) along with airway blocks and Group (H) (n = 30) patients received standard dose of dexmedetomidine (1 μg/kg) along with airway blocks. Both the groups received dexmedetomidine infusion over 10 min followed by airway block. Quantitative data were analysed by applying Student's t-test whereas qualitative data were analysed with Chi-square test. The objectives were to compare patients' Observer's Assessment of Alertness/Sedation scale (OAA/S) as primary outcome and other variables such as endoscopy, intubation condition, tolerance and haemodynamic stability among low and standard doses of dexmedetomidine.

Results

Group H had more favourable OAA/S score than that of Group L, but endoscopy and intubation time, patient tolerance, vocal cord and limb movement and satisfaction score did not differ significantly between the groups. There were no significant haemodynamic differences between the two groups.

Conclusion

The 0.5 μg/kg dose of dexmedetomidine was found optimal and effective in combination with topical spray and airway blocks for awake orotracheal fibre-optic intubation for patients undergoing elective cervical spine surgery.

The Safety and Efficacy of Dexmedetomidine vs. Sufentanil in Monitored Anesthesia Care during Burr-Hole Surgery for Chronic Subdural Hematoma: A Retrospective Clinical Trial

Background: Chronic subdural hematoma (CSDH) is a very common clinical emergency encountered in neurosurgery. While both general anesthesia (GA) and monitored anesthesia care (MAC) can be used during CSDH surgery, MAC is the preferred choice among surgeons. Further, while dexmedetomidine (DEX) is reportedly a safe and effective agent for many diagnostic and therapeutic procedures, there have been no trials to evaluate the safety and efficacy of DEX vs. sufentanil in CSDH surgery.

Objective: To evaluate the safety and efficacy of DEX vs. sufentanil in MAC during burr-hole surgery for CSDH.

Methods: In all, 215 fifteen patients underwent burr-hole surgery for CSDH with MAC and were divided into three groups: Group D1 (n = 67, DEX infusion at 0.5 μg·kg⁻¹ for 10 min), Group D2 (n = 75, DEX infusion at 1 μg·kg⁻¹ for 10 min), and Group S (n = 73, sufentanil infusion 0.3 μg·kg⁻¹ for 10 min). Ramsay sedation scale (RSS) of all three groups was maintained at 3. Anesthesia onset time, total number of intraoperative patient movements, hemodynamics, total cumulative dose of DEX, time to first dose and amount of rescue midazolam or fentanyl, percentage of patients converted to alternative sedative or anesthetic therapy, postoperative recovery time, adverse events, and patient and surgeon satisfaction scores were recorded.

Results: The anesthesia onset time was significantly less in group D2 (17.36 ± 4.23 vs. 13.42 ± 2.12 vs. 15.98 ± 4.58 min, respectively, for D1, D2, S; P < 0.001). More patients in groups D1 and S required rescue midazolam to achieve RSS = 3 (74.63 vs. 42.67 vs. 71.23%, respectively, for D1, D2, S; P < 0.001). However, the total dose of rescue midazolam was significantly higher in group D1 (2.8 ± 0.3 vs. 1.9 ± 0.3 vs. 2.0 ± 0.4 mg, respectively, for D1, D2, S; P < 0.001). The time to first dose of rescue midazolam was significantly longer in group D2 (17.32 ± 4.47 vs. 23.56 ± 5.36 vs. 16.55 ± 4.91 min, respectively, for D1, D2, S; P < 0.001). Significantly fewer patients in groups S and D2 required rescue fentanyl to relieve pain (62.69 vs. 21.33 vs. 27.40%, respectively, for D1, D2, S; P < 0.001). Additionally, total dose of rescue fentanyl in group D1 group was significantly higher (212.5 ± 43.6 vs. 107.2 ± 35.9 vs. 98.6 ± 32.2 μg, respectively, for D1, D2, S; P < 0.001). Total number of patient movements during the burr-hole surgery was higher in groups D1 and S (47.76 vs. 20.00 vs. 47.95%, respectively, for D1, D2, S; P < 0.001). Four patients in D1 and five in S converted to propofol. The time to recovery for discharge from the PACU was significantly shorter in group D2 (16.24 ± 4.15 vs. 12.48 ± 3.29 vs. 15.91 ± 3.66 min, respectively, for D1, D2, S; P < 0.001). Results from the patient and surgeon satisfaction scores showed significant differences favoring group D2 (P < 0.05). More patients in groups D1 and S showed higher levels of the overall incidence of tachycardia and hypertension, and required higher doses of urapidil and esmolol (P < 0.05). Six patients experienced respiratory depression in group S.

Conclusion: Compared with sufentanil, DEX infusion at 1 μg·kg⁻¹ was associated with fewer intraoperative patient movements, fewer rescue interventions, faster postoperative recovery, and better patient and surgeon satisfaction scores and could be safely and effectively used for MAC during burr-hole surgery for CSDH.

A Retrospective Study of Success, Failure, and Time Needed to Perform Awake Intubation

Background

Awake intubation is the standard of care for management of the anticipated difficult airway. The performance of awake intubation may be perceived as complex and time-consuming, potentially leading clinicians to avoid this technique of airway management. This retrospective review of awake intubations at a large academic medical center was performed to determine the average time taken to perform awake intubation, its effects on hemodynamics, and the incidence and characteristics of complications and failure.

Methods

Anesthetic records from 2007 to 2014 were queried for the performance of an awake intubation. Of the 1,085 awake intubations included for analysis, 1,055 involved the use of a flexible bronchoscope. Each awake intubation case was propensity matched with two controls (1:2 ratio), with similar comorbidities and intubations performed after the induction of anesthesia (n = 2,170). The time from entry into the operating room until intubation was compared between groups. The anesthetic records of all patients undergoing awake intubation were also reviewed for failure and complications.

Results

The median time to intubation for patients intubated post induction was 16.0 min (interquartile range: 13 to 22) from entrance into the operating room. The median time to intubation for awake patients was 24.0 min (interquartile range: 19 to 31). The complication rate was 1.6% (17 of 1,085 cases). The most frequent complications observed were mucous plug, endotracheal tube cuff leak, and inadvertent extubation. The failure rate for attempted awake intubation was 1% (n = 10).

Conclusions

Awake intubations have a high rate of success and low rate of serious complications and failure. Awake intubations can be performed safely and rapidly.