Evaluation of nebulised dexmedetomidine in blunting haemodynamic response to intubation: A prospective randomised 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.

Intraoperative thoracic interfascial plane block with levobupivacaine versus levobupivacaine with dexmedetomidine for postoperative analgesia after modified radical mastectomy: A randomised controlled double-blinded trial

Background and Aims

Nearly half of the patients following breast cancer surgery experience postoperative pain. The interfascial plane for the pectoral nerve (PECS) block, along with dexmedetomidine, can alleviate this pain.

Methods

After institutional ethics committee clearance and written informed consent, this randomised, double-blind study was conducted on 60, 18-60 years female patients, who were scheduled for modified radical mastectomy (MRM) under general anaesthesia. Patients were randomised into Group L (20 ml of 0.25% levobupivacaine) and Group DL (20 ml of 0.25% levobupivacaine with 0.5 µg/kg of dexmedetomidine). After resection of the tumour and securing haemostasis, under strict aseptic precaution, 10 ml of the study drug was injected under direct vision between the pectoralis major and pectoralis minor and 10 ml between pectoralis minor and serratus anterior muscles by the operating surgeon (direct PECS block). The primary outcome was to compare the duration of analgesia. Normally distributed variables were compared using Student's t-test, and non-normally distributed variables were compared using the Mann-Whitney U-test. Qualitative data were analysed using Chi-square/Fisher's exact test. Statistical significance was kept at P < 0.05.

Results

The median time of the first analgesic requirement was 8 [inter-quartile range (IQR): 6-8] h in Group L and 18 (IQR: 16-20) h in Group DL (W = 17.000, P < 0.001). The mean total opioid consumption of Group L was 12.53 [standard deviation (SD): 2.29] mg in the first 24 h and 6.93 (SD: 1.89) mg in Group DL.

Conclusion

Adding 0.5 μg/kg dexmedetomidine to 20 ml of levobupivacaine enhances the duration of analgesia of direct PECS block in patients undergoing MRM.

Clinical usefulness of nebulized dexmedetomidine for conscious sedation in daycare flexible bronchoscopy in Southern India

BACKGROUND

Sedative agents used in bronchoscopy require trained personnel to administer and monitor the patient. This increases the procedure cost, duration, and inpatient stay. Inhalational administration of sedative agents can be a practical solution to the issue. Dexmedetomidine in the inhalational form could give results similar to the intravenous form without significant adverse events.

MATERIALS AND METHODS

The study is prospective, randomized, and double-blinded study. Patients needing bronchoscopy were randomized to receive the nebulized form of either dexmedetomidine or saline (0.9%) before bronchoscopy. The study parameters are assessed and recorded before, during, and after bronchoscopy. Data collected are analyzed using the SPSS software.

DISCUSSION

The side effects limit using commonly administered sedation agents in bronchoscopy, such as midazolam, fentanyl, and dexmedetomidine. The nebulized dexmedetomidine is safe with proven efficacy when compared to the placebo. Proceduralist-administered conscious sedation reduces the overall cost and shortens inpatient stays. Attenuation of hemodynamic parameters by dexmedetomidine could be an advantage for the physician in reducing an untoward cardiac event.

CONCLUSION

Dexmedetomidine in the nebulized form improves the comfort of patients during the procedure. It blunts the pressure response during bronchoscopy and could be a safer and cost-effective agent in its nebulized form for conscious sedation in bronchoscopy. The study is approved by the institutional ethics committee (IEC KMC MLR 10-2021-310).

Comparative evaluation of nebulised dexmedetomidine vs fentanyl for the treatment of post-dural puncture headache (PDPH) in parturients after caesarean section under spinal anaesthesia: A randomised controlled study

Background and Aims

The incidence of post-dural puncture headache (PDPH) following spinal anaesthesia in the obstetric population is around 0.5%-2%. Hydration, bed rest, caffeine, paracetamol, non-steroid anti-inflammatory drugs, epidural blood patches, etc., are the various modalities used for its management. This study aims to compare nebulised dexmedetomidine versus fentanyl for the treatment of PDPH in parturients after caesarean section under spinal anaesthesia.

Methods

Ninety obstetric patients aged 18-35 years with American Society of Anesthesiologists (ASA) physical status II/III and suffering from PDPH as per the criteria of the International Headache Society after caesarean section under spinal anaesthesia were recruited in this double-blinded randomised study. Patients were randomised to Group D (dexmedetomidine 1 µg/kg nebulisation), Group F (fentanyl 1 µg/kg nebulisation), and Group S (saline nebulisation 4mL). The nebulisation was done 12 hourly for 72 hours. Assessment parameters included pain score and the requirement of additional treatment such as paracetamol, caffeine, and epidural blood patch. Analysis of variance test was used for continuous quantitative variables, and the Kruskal-Wallis test was used for quantitative discrete data.

Results

The pain scores at 1, 6, 12, 24, 48, and 72 hours following nebulisation were significantly lower in Group D in comparison to groups F and S (P < 0.001). The number of patients requiring additional analgesic therapy was lower in Group D in comparison to patients in other groups (P < 0.001).

Conclusion

Dexmedetomidine nebulisation resulted in effective reduction in PDPH symptoms and pain scores. Nebulisation with fentanyl did not alleviate PDPH symptoms when compared to the control group.

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.

Comparison of nebulized ropivacaine (0.75%) with nebulized dexmedetomidine on the hemodynamic response on intubation in patients undergoing surgery under general anesthesia: A comparative randomized double-blind placebo-controlled study

Background

Laryngoscopy and tracheal intubation lead to sympathetic stimulation resulting in hemodynamic fluctuations. We compared local anesthetic ropivacaine 0.75% with alpha agonist dexmedetomidine through ultrasonic nebulization for direct local action of the drug in the airway.

Methods

In our randomized study, 180 patients were prospectively assigned to three groups of 60 each: group R (0.75%), group D (1 microgram/kg), and group C (control). The primary objective was to determine whether nebulized ropivacaine or nebulized dexmedetomidine can cause a reduction in stress response to laryngoscopy and intubation. The secondary objectives were to compare the hemodynamic parameters at extubation, cough response at extubation, and postoperative sore throat.

Results

A total of 165 patients were analyzed. Demographically, all the groups were similar. Group R and group D were found to significantly attenuate the heart rate (HR) at intubation and extubation when compared to group C (P < 0.05). A significant reduction in mean arterial pressure (MAP) was seen (P < 0.05; group D: 90 ± 18.4 mmHg, group C: 99.5 ± 15.9 mmHg, group R: 92.4 ± 16.1 mmHg). There was a significant reduction in cough response in both groups in comparison with group C at 0 minutes (P value; group C vs group D: <.0001; group C vs group R:.01) and 5 minutes (P value; group C vs group D: <.0001; group C vs group R: <.0001).

Conclusion

Preinduction topical use of ropivacaine or dexmedetomidine, through the nebulization route, effectively attenuated the pressor responses when compared to placebo.

A prospective-randomized placebo-controlled trial comparing the effects of nebulized dexmedetomidine v/s dexmedetomidine-lignocaine mixture on intraoperative hemodynamics and surgical field quality in patients undergoing endoscopic transnasal transsphenoidal pituitary tumor surgery

Background

During transnasal transsphenoidal pituitary surgery (TNTSS), the primary objective is to maintain stable hemodynamics while ensuring ideal surgical conditions. This study aimed to investigate the effect of nebulized dexmedetomidine on hemodynamic parameters and the quality of the surgical field during TNTSS.

Methods

Seventy-five patients scheduled for TNTSS were randomized into three groups of 25 each and received preoperative nebulization with 5 mL of nebulizing fluid consisting of 1.5 μg/kg of dexmedetomidine with saline in dexmedetomidine (D) group; 1.5 μg/kg of dexmedetomidine with 2% lignocaine in dexmedetomidine-lignocaine (DL) group and normal saline in the control (S) group. Heart rate (HR), mean blood pressure, Formmers score, anesthetic requirement, and emergence were evaluated for each group.

Results

Group S had significantly higher HR and mean arterial pressure than the other two groups across various time points during surgery (P < 0.01). The total requirements for fentanyl, propofol, sevoflurane, and labetalol and the incidence of delayed emergence were significantly higher in the S group compared to the other two groups (P < 0.01). The D and DL groups exhibited significantly better surgical field conditions than the S group. In all the parameters assessed, patients in the D group outperformed those in the DL group.

Conclusion

The administration of nebulized dexmedetomidine, both alone and in combination with lignocaine, resulted in stable hemodynamics, favorable operative conditions, reduced anesthetic requirement, and facilitated prompt emergence during TNTSS. Nebulized dexmedetomidine proved superior to its combination with lignocaine across all evaluated parameters.

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.

Nebulised fentanyl, dexmedetomidine and magnesium sulphate for attenuation of haemodynamic response to laryngoscopy and tracheal intubation: A double-blinded, randomised comparative study

Background and Aims

Direct laryngoscopy and tracheal intubation cause an increase in heart rate (HR) and blood pressure, called as pressor response. This study aimed to compare nebulised forms of fentanyl, dexmedetomidine and magnesium sulphate to attenuate the haemodynamic response to laryngoscopy and tracheal intubation.

Methods

This double-blinded, randomised study was conducted on 90 patients undergoing elective surgery requiring endotracheal intubation. Nebulisation was done with fentanyl 1 μg/kg (Group A), dexmedetomidine 1 μg/kg (Group B) and magnesium sulphate (MgSO4) (40 mg/kg) (Group C). Systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP) and HR were recorded before nebulisation (T0), post-nebulisation (T1) and at 2, 5 and 10 min after intubation (T2, T3, T4). The statistical analysis for comparing continuous variables between the groups was performed using analysis of variance (ANOVA), and a P value <0.05 was considered statistically significant.

Results

Compared to T0, an increase in HR at T2 and T3 was seen in Group A only, which reached baseline values at T4 (P values <0.0001 and 0.037, respectively). No HR value was higher than the baseline readings in groups B and C. The decreasing trend of SBP, DBP and MAP was seen in all three groups. Groups B and C had a statistically significant decrease in all the values from baseline (P values <0.0001).

Conclusion

Nebulised form of dexmedetomidine (1 μg/kg) and magnesium (40 mg/kg) seems to be superior to fentanyl (1 μg/kg) in blunting the stress response to laryngoscopy and tracheal intubation.

A Randomized Comparison of Intravenous Versus Nebulized Routes for Administering Dexmedetomidine and Ketamine Combination to Facilitate Awake Fibreoptic Intubation

Introduction Awake fibreoptic intubation is a technique used to secure the airway of patients who are having predicted difficult intubation. We compared two routes, intravenous and nebulized, for administering a combination of ketamine and dexmedetomidine to patients requiring sedation for fibreoptic intubation. Methods and materials After approval of the institutional ethics committee, 64 patients between 18 and 60 years belonging to the American Society of Anesthesiologists physical status I or II and having predicted difficult airway were randomized to receive study medications through either intravenous (group I, n = 32) or nebulized (group N, n = 32) routes. Group I patients were given a combination of ketamine and dexmedetomidine through intravenous route. Group N patients were nebulized with a combination of ketamine and dexmedetomidine. The time required for awake fiberoptic intubation was the primary outcome variable. In addition, sedation score, cough severity, patient tolerance, intubating condition, hemodynamic changes, recall of events and discomfort during intubation, and any adverse events in the perioperative period were also compared. Results Compared to group N, the time needed to intubate the patients was significantly less in group I (75.69 ± 10.83 versus 49.19 ± 3.60 seconds, p < 0.001). Observer assessment sedation/alertness score (p < 0.001), cough severity (p < 0.001), patient tolerance (p < 0.001), and intubating condition (p = 0.001) were statistically significant, all conditions being better in group I. Patient discomfort and recall of the procedure were statistically similar between the groups. Conclusions The efficacy of a combination of dexmedetomidine and ketamine through the intravenous route is better than the nebulized route for patients undergoing awake fibreoptic intubation.

Reduction in postoperative sore throat by preoperative nebulization with dexmedetomidine, ketamine or saline: A prospective, randomized-controlled trial

Background and Aims

Postoperative sore throat (POST) is a minor but distressing complication following general anesthesia. The current literature on the effect of preoperative nebulization with dexmedetomidine, or ketamine on POST is, however, sparse. So, we compared the effect of preoperative nebulization with these drugs on POST.

Material and Methods

One hundred and thirty-two American Society of Anaesthesiology (ASA) grade I-II patients undergoing elective laparoscopic surgeries under general anesthesia were randomized into three equal groups: D, K, or C to receive dexmedetomidine, ketamine, or saline as preoperative nebulization, respectively. The primary objective was to compare the incidence and severity of POST, as inferred from the patient interviews at 2, 6, 12, 24-h postoperatively.

Results

Group D had a significantly lower incidence (29.5%) and severity (12: mild; 1: moderate) of POST compared to group K (54.5% [21: mild; 3: moderate]) and group C (56.8% [19: mild; 6: moderate]), at 2-h postoperatively. The same trend was observed at 6-h postoperatively (group D: 22.7% [9: mild; 1: moderate]); group K: (40.9% [17: mild; 1: moderate]); group C (50% [17: mild; 5: moderate]). The mean arterial pressure was significantly lower in group D at 15 min intraoperatively (84.09 mmHg, P = 0.018) and immediate postoperatively (97.60 mmHg, P = 0.034). The postoperative sedation, nausea, and vomiting was not statistically significant.

Conclusion

Preoperative nebulization with dexmedetomidine is effective in the reduction of the incidence and severity of early POST.

Efficacy of IM dexmedetomidine in alleviating catheter related bladder discomfort and postoperative inflammatory response following percutaneous nephrolithotomy. A prospective randomized controlled study

Background and Aims

Catheter-related bladder discomfort (CRBD) causes significant distress to the patient and requires great attention to analgesia and increases morbidity in the postoperative period. This study evaluated the efficacy of intramuscular dexmedetomidine in alleviating CRBD following percutaneous nephrolithotomy (PCNL) and postoperative inflammatory response.

Material and Methods

A prospective randomized double-blind study was conducted in a tertiary care hospital from December 2019- March 2020. Sixty seven of ASA I and II patients scheduled for elective PCNL were randomized and group I received 1 μg/kg dexmedetomidine intramuscularly and group II normal saline as control 30 minutes before induction of anesthesia. Standard anesthesia protocol was followed and patients were catheterized with 16 Fr Foleys after induction of anesthesia. Rescue analgesia was paracetamol if the score was moderate. Postoperatively CRBD score and inflammatory markers; total white cell count, erythrocyte sedimentation rate and temperature were noted for 3 days.

Results

There was a significant low CRBD score in group I. Ramsay sedation score was 2 in group I with p 0.00 and rescue analgesia required was very low with p 0.00. Statistical Package for social Sciences software version 20 was used for analysis. Student ttest, analysis of variance, and Chisquare test were applied for quantitative and qualitative analysis respectively.

Conclusion

Single dose intramuscular dexmedetomidine is effective, simple and safe in preventing the CRBD and the inflammatory response remained uninfluenced except ESR, the reason remains largely unknown.

Comparison of Intravenous Versus Nebulized Dexmedetomidine for Laryngoscopy and Intubation-Induced Sympathoadrenal Stress Response Attenuation

Background

Nebulized dexmedetomidine has been used for procedural sedation and allaying separation anxiety in children. Literature regarding its use in the attenuation of laryngoscopy and intubation response via the nebulized route is scarce. We evaluated preoperative dexmedetomidine nebulization on the hemodynamic response arising from laryngoscopy/intubation, hemodynamics, analgesic consumption, and postoperative sore throat.

Objectives

The primary objective was to evaluate/compare the hemodynamic effects of preoperative intravenous and nebulized dexmedetomidine on laryngoscopy/intubation and compare the efficacy of the two routes in blunting the sympathoadrenal response. The secondary objective was to evaluate their effects on intraoperative analgesic consumption and incidence and sore throat postoperatively.

Methods

120 ASA I & II adult patients undergoing elective surgeries requiring tracheal intubation were randomized to receive intravenous dexmedetomidine (1 µg/kg over 10 minutes) and nebulized dexmedetomidine (1 µg/kg in 3 - 4 mL of 0.9% saline), 30 min before anesthesia induction. Heart rate and non-invasive blood pressure were monitored for 10 min following laryngoscopy and then throughout the surgery. Intraoperative analgesic consumption, postoperative sore throat, and recovery from anesthesia were assessed.

Results

No significant hemodynamic difference was found between the two groups till three minutes. Then, the difference turned significant owing to a greater fall in the heart rate and mean arterial pressure in the intravenous group. Nebulized dexmedetomidine exhibited a lesser tendency of hypo/hypertension and brady/tachycardia, while hemodynamics was more stable. There was lesser sore throat and sedation in the nebulized group. Intraoperative analgesic and propofol consumption was comparable between the two groups.

Conclusions

Nebulized dexmedetomidine attenuated laryngoscopy and intubation response, although to a lesser extent than the intravenous group in equivalent doses. However, the nebulized route provided greater hemodynamic stability in the intraoperative period and lesser sedation/sore throat postoperatively without an increase in adverse effects. Nebulized dexmedetomidine may provide a more holistic and viable alternative in patients who poorly tolerate hypotension, bradycardia, and sedation.

A Comparative Study between Local Dexmedetomidine and Intravenous Dexmedetomidine during Awake Fiberoptic Nasotracheal Intubation

Background

Awake fiberoptic intubation (AFOI) is the gold standard for managing a difficult airway. To make the patient comfortable and cooperative during the procedure, many drugs such as benzodiazepines, opioids, or dexmedetomidine are used. Most of these intravenously given drugs may cause respiratory depression and hypoxia.

Aim

We compared the efficacy of dexmedetomidine through nebulization and transtracheal route with intravenous routes with the primary aim of comparing patient tolerance score (PTS) and secondary objectives of comparing sedation score, cough score, and total duration required for awake fiberoptic nasotracheal intubation.

Settings and Design

This study was a prospective randomized double-blind study.

Subjects and Methods

Seventy-six patients, scheduled for elective surgery requiring AFOI between 18 and 75 years, were included in the study. They were randomly divided into two groups of 38 each. Group I patients received intravenous dexmedetomidine 1 μg.kg-1 and Group L patients received local dexmedetomidine through nebulization 0.5 μg.kg-1 and transtracheal injection 0.5 μg.kg-1.

Statistical Analysis Used

Statistical Package for the Social Sciences version 22 was used.

Results

Patients who received dexmedetomidine through nebulization and transtracheal route have significantly better PTSs and less cough scores as compared to patients who received dexmedetomidine by intravenous route (P < 0.05). Hemodynamic parameters and sedation scores between the two groups were statistically insignificant (P > 0.05). The time required for the procedure was significantly less in Group L compared to Group I (P < 0.05).

Conclusion

Dexmedetomidine by nebulization and transtracheal route provides optimal conditions for AFOI with good patient tolerance and less cough score as compared to the intravenous route.

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.

Recent Advances in the Clinical Value and Potential of Dexmedetomidine

Dexmedetomidine, a highly selective α2-adrenoceptor agonist, has sedative, anxiolytic, analgesic, sympatholytic, and opioid-sparing properties and induces a unique sedative response which shows an easy transition from sleep to wakefulness, thus allowing a patient to be cooperative and communicative when stimulated. Recent studies indicate several emerging clinical applications via different routes. We review recent data on dexmedetomidine studies, particularly exploring the varying routes of administration, experimental implications, clinical effects, and comparative advantages over other drugs. A search was conducted on the PubMed and Web of Science libraries for recent studies using different combinations of the words “dexmedetomidine”, “route of administration”, and pharmacological effect. The current routes, pharmacological effects, and application categories of dexmedetomidine are presented. It functions by stimulating pre- and post-synaptic α2-adrenoreceptors within the central nervous system, leading to hyperpolarization of noradrenergic neurons, induction of an inhibitory feedback loop, and reduction of norepinephrine secretion, causing a sympatholytic effect, in addition to its anti-inflammation, sleep induction, bowel recovery, and sore throat reduction effects. Compared with similar α2-adrenoceptor agonists, dexmedetomidine has both pharmacodynamics advantage of a significantly greater α2:α1-adrenoceptor affinity ratio and a pharmacokinetic advantage of having a significantly shorter elimination half-life. In its clinical application, dexmedetomidine has been reported to present a significant number of benefits including safe sedation for various surgical interventions, improvement of intraoperative and postoperative analgesia, sedation for compromised airways without respiratory depression, nephroprotection and stability of hypotensive hemodynamics, reduction of postoperative nausea and vomiting and postoperative shivering incidence, and decrease of intraoperative blood loss. Although the clinical application of dexmedetomidine is promising, it is still limited and further research is required to enhance understanding of its pharmacological properties, patient selection, dosage, and adverse effects.

Comparison of hypotensive properties of dexmedetomidine versus clonidine for induced hypotension during functional endoscopic sinus surgery: A randomised, double-blind interventional study

Background and Aims

Excessive bleeding is a major concern in functional endoscopic sinus surgery (FESS) under general anaesthesia; this can be decreased by various hypotensive agents. This study was conducted to compare the hypotensive effectiveness and haemodynamic stability of dexmedetomidine and clonidine in patients undergoing elective FESS.

Methods

In this prospective double-blinded interventional study, 70 adult patients of either sex, 20-50 years of age, posted for elective FESS were randomly assigned to two groups. Group A received a loading dose of intravenous (IV) dexmedetomidine 1 μg/kg, followed by infusion of 1 μg/kg/h, and group B received a loading dose of IV clonidine 2 μg/kg, followed by 1 μg/kg/h infusion. Surgical field quality, emergence time, sedation score, visual analogue score, recovery profile and haemodynamic parameters were recorded. Statistical analysis was done by Student's unpaired t-test to evaluate the significance of normally distributed variables, whereas Mann-Whitney test and Chi-square test were used for ordinal data and categorical variables and proportions, respectively.

Results

In both the groups, target mean arterial pressure (MAP) of 65-70 mmHg and improved surgical field quality were achieved. MAP and heart rate (HR) were statistically significantly lower in the dexmedetomidine group with a longer duration of post-operative analgesia (P = 0.001). None of the groups showed any statistically significant adverse effects.

Conclusions

Both dexmedetomidine and clonidine can be used for controlled hypotension to improve surgical field quality in FESS. Dexmedetomidine provides more haemodynamic stability and an additional benefit of post-operative analgesia and conscious sedation.

Depth of Anesthesia Monitoring

The electroencephalogram (EEG) can be analyzed in its raw form for characteristic drug-induced patterns of change or summarized using mathematical parameters as a processed electroencephalogram (pEEG). In this article we aim to summarize the contemporary literature pertaining to the commonly available pEEG monitors including the effects of commonly used anesthetic drugs on the EEG and pEEG parameters, pEEG monitor pitfalls, and the clinical implications of pEEG monitoring for anesthesia, pediatrics, and intensive care.

Effectiveness of nebulized dexmedetomidine for treatment of post-dural puncture headache in parturients undergoing elective cesarean section under spinal anesthesia: a randomized controlled study

PURPOSE

The need for effective treatment for post-dural puncture headache (PDPH) is a growing research entity. This study aimed to test the effectiveness of additional dexmedetomidine (DEX) to PDPH conservative management and evaluate its cerebral hemodynamic effects trans-cranial Doppler.

METHODS

This prospective randomized double-blind controlled trial was conducted on 43 post-partum females suffering from PDPH with visual analog score (VAS) ≥ 4 and Lybecker score ≥ 2. The study subjects were allocated into control group [n = 22] received nebulization of 4 mL 0.9% saline and DEX group [n = 21] received nebulization of 1 µg/kg DEX diluted in 4 mL 0.9% saline twice daily that was continued until achieving VAS score ≤ 3 and Lybecker score < 2 and/or for a maximum of 72 h. Both groups received routine conservative management. The primary outcome was the VAS and Lybecker scores and the secondary results were the DEX effects on cerebral vessels and the occurrence of any adverse effects.

RESULTS

VAS and Lybecker scores were significantly lower in DEX group. The middle cerebral artery mean flow velocity was significantly lower, and the pulsatility index was considerably higher after DEX nebulization compared to placebo. Two patients in the control group were indicated for epidural blood patch.

CONCLUSION

The addition of DEX nebulization (1 µg/kg twice daily) to the PDPH conservative care effectively relieved the symptoms and lowered pain scores which could be due to its analgesic and cerebral vasoconstrictive effects.

TRIAL REGISTRATION

This study was approved by the research ethical committee of Faculty of Medicine, Zagazig University with the reference number (ZU-IRB#: 6075/26-4-2020) and it was registered under clinicaltrials.gov (NCT04327726).