Comparison between dexmedetomidine and propofol for sedation in the intensive care unit: patient and clinician perceptions

Mapping Theme Trends and Research Frontiers in Dexmedetomidine Over Past Decade: A Bibliometric Analysis

Background

Dexmedetomidine, an α2-adrenergic receptor (α2-AR) agonist, is extensively used in clinical and animal studies owing to its sedative, analgesic, and anxiolytic effects. The diverse range of research domains associated with dexmedetomidine poses challenges in defining pivotal research directions. Therefore, this study aimed to conduct a qualitative and quantitative bibliometric study in the field of dexmedetomidine over the past decade to establish current research trends and emerging frontiers.

Methods

Relevant publications in the field of dexmedetomidine between 2014 and 2023 were extracted from the Web of Science Core Collection database. The bibliometric analysis, incorporating statistical and visual analyses, was conducted using CiteSpace (6.1.R6) and R (4.3.1).

Results

The present study encompassed a total of 5,482 publications, exhibiting a consistent upward trend over the past decade. The United States and its institutions had the highest centrality. Ji, Fuhai, and Ebert, Thomas J. were identified as the most productive author and the most cited author, respectively. As anticipated, the most cited journal was Anesthesiology. Moreover, cluster analysis of cited references and co-occurrence of keywords revealed that recent studies were primarily focused on sedation, delirium, and opioid-free anesthesia. Finally, a timeline view of keywords clusters and keywords burst demonstrated that primary research frontiers were stress response, neuroinflammation, delirium, opioid-free anesthesia, peripheral nerve block, and complications.

Conclusion

Current research trends and directions are focused on sedation, delirium, and opioid-free anesthesia, as evidenced by our results. The frontier of future research is anticipated to encompass basic investigations into dexmedetomidine, including stress response and neuroinflammation, as well as clinical studies focusing on delirium, opioid-free anesthesia, peripheral nerve block, and associated complications.

Comparison of dexmedetomidine versus propofol sedation on microcirculation and organ injuries in critically ill surgical patients: A randomized controlled pilot study

BACKGROUND

Recent studies have shown that dexmedetomidine may improve microcirculation and prevent organ failure. However, most evidence was obtained from experimental animals and patients receiving cardiac surgery with cardiopulmonary bypass. This study aimed to investigate the effect of dexmedetomidine on microcirculation and organ injuries in critically ill general surgical patients.

METHODS

In this prospective randomized trial, patients admitted to the surgical intensive care unit after general surgery were enrolled and randomly allocated to the dexmedetomidine or propofol groups. Patients received continuous dexmedetomidine or propofol infusions to meet their requirement of sedation according to their grouping. At each time point, sublingual microcirculation images were obtained using the incident dark field video microscope.

RESULTS

Overall, 60 patients finished the trial and were analyzed. Microcirculation parameters did not differ significantly between two groups. Heart rate at 4 h after ICU admission and mean arterial pressures at 12 h and 24 h after ICU admission were lower in the dexmedetomidine group than in the propofol group. At 24 h, serum aspartate aminotransferase (41 (25-118) vs 86 (34-129) U/L, p = 0.035) and alanine aminotransferase (50 (26-160) vs 68 (35-172) U/L, p = 0.019) levels were significantly lower in the dexmedetomidine group than in the propofol group.

CONCLUSION

Microcirculation parameters did not differ significantly between the dexmedetomidine and propofol groups. At 24 h after ICU admission, serum liver enzyme levels were lower in patients receiving dexmedetomidine as compared to propofol.

Dexmedetomidine post-treatment exacerbates metabolic disturbances in septic cardiomyopathy via α2A-adrenoceptor

Cardiomyopathy is a common complication and significantly increases the risk of death in septic patients. Our previous study demonstrated that post-treatment with dexmedetomidine (DEX) aggravates septic cardiomyopathy. However, the mechanisms for the side effect of DEX post-treatment on septic cardiomyopathy are not well-defined. Here we employed a cecal ligation and puncture (CLP) model and α2A-adrenoceptor deficient (Adra2a-/-) mice to observe the effects of DEX post-treatment on myocardial metabolic disturbances in sepsis. CLP mice displayed significant cardiac dysfunction, altered mitochondrial dynamics, reduced cardiac lipid and glucose uptake, impaired fatty acid and glucose oxidation, enhanced glycolysis and decreased ATP production in the myocardium, almost all of which were dramatically enhanced by DEX post-treatment in septic mice. In Adra2a-/- mice, DEX post-treatment did not affect cardiac dysfunction and metabolic disruptions in CLP-induced sepsis. Additionally, Adra2a-/- mice exhibited impaired cardiac function, damaged myocardial mitochondrial structures, and disturbed fatty acid metabolism and glucose oxidation. In sum, DEX post-treatment exacerbates metabolic disturbances in septic cardiomyopathy in a α2A-adrenoceptor dependent manner.

Dexmedetomidine Alters the Inflammatory Profile of Rat Microglia In Vitro

BACKGROUND

Microglia are a primary mediator of the neuroinflammatory response to neurologic injury, such as that in traumatic brain injury. Their response includes changes to their cytokine expression, metabolic profile, and immunophenotype. Dexmedetomidine (DEX) is an α2 adrenergic agonist used as a sedative in critically ill patients, such as those with traumatic brain injury. Given its pharmacologic properties, DEX may alter the phenotype of inflammatory microglia.

METHODS

Primary microglia were isolated from Sprague-Dawley rats and cultured. Microglia were activated using multiple mediators: lipopolysaccharide (LPS), polyinosinic-polycytidylic acid (Poly I:C), and traumatic brain injury damage-associated molecular patterns (DAMP) from a rat that sustained a prior controlled cortical impact injury. After activation, cultures were treated with DEX. At the 24-h interval, the cell supernatant and cells were collected for the following studies: cytokine expression (tumor necrosis factor-α [TNFα], interleukin-10 [IL-10]) via enzyme-linked immunosorbent assay, 6-phosphofructokinase enzyme activity assay, and immunophenotype profiling with flow cytometry. Cytokine expression and metabolic enzyme activity data were analyzed using two-way analysis of variance. Cell surface marker expression was analyzed using FlowJo software.

RESULTS

In LPS-treated cultures, DEX treatment decreased the expression of TNFα from microglia (mean difference = 121.5 ± 15.96 pg/mL; p < 0.0001). Overall, DEX-treated cultures had a lower expression of IL-10 than nontreated cultures (mean difference = 39.33 ± 14.50 pg/mL, p < 0.0001). DEX decreased IL-10 expression in LPS-stimulated microglia (mean difference = 74.93 ± 12.50 pg/mL, p = 0.0039) and Poly I:C-stimulated microglia (mean difference = 23.27 ± 6.405 pg/mL, p = 0.0221). In DAMP-stimulated microglia, DEX decreased the activity of 6-phosphofructokinase (mean difference = 18.79 ± 6.508 units/mL; p = 0.0421). The microglial immunophenotype was altered to varying degrees with different inflammatory stimuli and DEX treatment.

CONCLUSIONS

DEX may alter the neuroinflammatory response of microglia. By altering the microglial profile, DEX may affect the progression of neurologic injury.

Dexmedetomidine-Oxycodone combination for conscious sedation during colonoscopy in obese patients: A randomized controlled trial

Background

Obesity is a risk factor for sedation-related respiratory depression during colonoscopy. In a colonoscopy, propofol is frequently used because of its strong sedative and hypnotic properties. However, propofol is associated with marked respiratory depression. The objective of this trial was to investigate the effectiveness and safety of dexmedetomidine plus oxycodone for conscious sedation during colonoscopy in obese patients.

Methods

A total of 120 patients had colonoscopies, and they were divided into two groups at random: Dexmedetomidine and oxycodone were used to sedate group Dex + oxy; while group Pro + oxy received anesthesia with propofol plus oxycodone. Parameters including blood pressure, heart rate, respiration, blood oxygen saturation, injection pain, and recovery time were recorded for both groups.

Results

The incidence of hypoxemia was significantly reduced in group Dex + oxy compared with group Pro + oxy (4.9% vs 20.3%, P = 0.011). Blood pressure was lower, and heart rate was higher in group Pro + oxy compared with group Dex + oxy (P < 0.05). In addition, group Dex + oxy showed a significantly shorter caecal insertion time, recovery time to orientation, and recovery time to walking than group Pro + oxy (P < 0.05). Endoscopist satisfaction scores were significantly higher in group Dex + oxy compared with group Pro + oxy (P = 0.042).

Conclusion

For obese patients, dexmedetomidine plus oxycodone effectively sedate them with few adverse effects, while also reducing colonoscopy operation difficulty by allowing obese patients to reposition. Thus, dexmedetomidine plus oxycodone could be used safely as a conscious sedation method for colonoscopy in obese patients.

Trial registration

The protocol was registered at www.chictr.org.cn (ChiCTR1800017283, July 21, 2018).

Considerations for Satisfactory Sedation during Dental Implant Surgery

Implant surgery is a lengthy dental procedure, and sedation is often used to reduce discomfort. The effectiveness of sedation has traditionally been evaluated in terms of patient and surgeon satisfaction, but the most important goal is not to induce a deep sleep in the patient, but rather to ensure that the surgery is performed safely and as planned. Additionally, adequate pain control is a necessary requirement for patient and surgeon satisfaction. Most patients undergoing implant surgery are middle-aged or older, and a relatively large number of them have cardiovascular disease. Infiltration anesthesia using articaine or lidocaine in combination with adrenaline is widely used, but its use in patients with cardiovascular disease is limited because of adrenaline's effects on the cardiovascular system. The use of long-acting local anesthetics and the potential efficacy of ultrasound-guided jaw nerve block have been investigated to enhance analgesia without resorting to adrenaline. Midazolam and propofol are usually used for sedation, but dexmedetomidine, which causes less respiratory depression, and the ultrashort-acting benzodiazepine remimazolam are emerging as potential alternatives. Monitoring of anesthetic depth using electroencephalography is effective in maintaining a constant level of sedation. In addition, sedation promotes the stabilization of heart rate and blood pressure, reducing the risks associated with adrenaline and allowing for safer management.

Analgesia-based Sedation for Oral Surgery in Patients With Chronic Respiratory Obstructive Disease

Chronic obstructive pulmonary disease (COPD) is a risk factor for postoperative cardiovascular and respiratory complications. Thus, intravenous sedation can be a better option than general anesthesia for surgery in patients with severe COPD. Herein, we present 2 cases of analgesia-based sedation in patients with severe COPD who underwent oral surgery. The current study aimed to discuss these cases to provide knowledge about the appropriate sedation management in patients with this disease. In the current cases, the patients received sufficient analgesia and minimum sedation (analgesia-based sedation). Moreover, dexmedetomidine was used for maintaining sedation and fentanyl for analgesic effects. Furthermore, we focused on providing the maximum analgesic effect of local anesthesia. The patients' vital signs were stable. They did not have any psychological or physical complaints, such as anxiety and pain, during the procedure. Then, they were discharged from the hospital without any complications. Thus, analgesia-based sedation can be an alternative option for oral surgery in patients with COPD.

A Retrospective Analysis of Guanfacine for the Pharmacological Management of Delirium

Background Delirium is a syndrome of acute brain failure that represents a change from an individual's baseline cognitive functioning characterized by deficits in attention and multiple aspects of cognition that fluctuate in severity over time. The symptomatic management of delirium's behavioral manifestations remains difficult. The alpha-2 agonists, dexmedetomidine and clonidine, are efficacious, but their potential cardiovascular adverse effects limit their utilization. Guanfacine is an oral alpha-2 agonist with a lower potential for such adverse outcomes; however, its use in delirium has not been studied. Methods A retrospective descriptive analysis of guanfacine for managing hyperactive or mixed delirium at Tampa General Hospital from January 2020 to October 2020 was conducted. The primary outcome was the time reduction in acute sedative administration. Secondary outcomes included renewed participation in physical therapy or occupational therapy (PT/OT), decreased opioid use, and an incidence of cardiovascular adverse effects. Results One hundred forty-nine patients were identified as having received guanfacine for managing delirium during the study period. All experienced a reduction in acute sedative use after the initiation of guanfacine. In 93 patients receiving PT/OT and no longer participating due to behavioral agitation, 74% had a documented renewal of services within four days. Of 112 patients on opioids, 70% experienced a 25% reduction in opioid administration within four days. No patients experienced consecutive episodes of hypotension that required a change in their clinical care. Two patients experienced a single episode of consecutive bradycardia that led to the discontinuation of guanfacine.  Conclusions Based on our retrospective study, guanfacine is a well-tolerated medication for the management of delirium. Even in medically and critically ill patients, cardiovascular adverse events were rare with guanfacine. Patients treated with guanfacine experienced decreased acute sedative use for behavioral agitation. Additionally, patients treated with guanfacine received fewer opioids and were better able to participate in PT/OT. Future studies with prospective, randomized, placebo-controlled designs are warranted to evaluate this promising intervention for delirium further.

Low-dose propofol as a solo agent for sedation in postoperative ventilated liver transplant recipients: A preliminary observational study

Background and Aims

Propofol is a commonly used sedative agent, in a dose of 1.5-4.5 mg.kg-1.h-1. Following liver transplantation (LT), drug metabolism may be altered due to liver mass, altered hepatic blood flow, reduced levels of serum proteins, and liver regeneration. Thus, we hypothesized that propofol requirements in this group of patients would be different as compared to the standard dose. This study evaluated the dose of propofol used for sedation in electively ventilated living donor liver transplantation (LDLT) recipients.

Material and Methods

After patients were shifted to the postoperative intensive care unit (ICU) following LDLT surgery, propofol infusion was started at a dose of 1 mg.kg-1.h-1 and titrated to maintain a bispectral index (BIS) value of 60-80. No other sedatives such as opioids or benzodiazepines were used. Dose of propofol, noradrenaline, and arterial lactate levels were noted 2 hourly.

Results

The mean propofol dose required in these patients was 1.02 ± 0.26 mg.kg-1.h-1. Noradrenaline was gradually tapered off and stopped within 14 h of shifting to ICU. The mean duration between the time of cessation of propofol infusion till extubation was 2.06 ± 1.44 h. Propofol dose did not correlate with respective lactate levels, ammonia levels, or graft-to-recipient weight ratio.

Conclusion

The dose range of propofol required for postoperative sedation in LDLT recipients was lower than the conventional dose.

Sedation With Dexmedetomidine in Critically Ill Burn Patients Reduced Delirium During Weaning From Mechanical Ventilation

INTRODUCTION

Weaning of mechanical ventilation while maintaining appropriate pain control and preventing delirium is one of the most challenging aspects of burn care. Dexmedetomidine, an α₂-adrenergic receptor agonist used for sedation may improve intensive care unit (ICU) patients' arousal status and enhance patient comfort.

OBJECTIVES

To determine the efficacy of dexmedetomidine vs. standardized usual care (midazolam or propofol) in maintaining sedation and reducing delirium in burn patients while weaning off mechanical ventilation.

MATERIAL AND METHODS

A total of 56 mechanically ventilated patients who fulfilled the criteria for weaning were enrolled in the study. Group 1 (26 patients) received dexmedetomidine 1 mcg/kg over 15 minutes as a loading dose, followed by 0.4-0.1 mcg/kg/h. Group 2 (30 patients) received usual sedation with midazolam 0.08 mg/kg/h or propofol 15- 30 mcg /kg/min).

RESULTS

 Dexmedetomidine was not associated with a significantly shorter duration of mechanical ventilation (Mean {IQR}: 9.3 {4,12} versus 7.5 {4,10}, p=0.3). Patients who received dexmedetomidine had a lower delirium rate (38,4% on Day 1 to 7,7% on Day 5) in comparison with patients from the usual care group (53,3% on Day 1 to 20% on Day 5) during the five days after the onset of weaning process (p=0.02) and had less need for supplemental use of analgesia (23.1% versus 53.3%, p=0.045) and antipsychotic agents (15.4% versus 53.3%, p=0.01). The most notable adverse effect of dexmedetomidine was bradycardia.

CONCLUSIONS

Dexmedetomidine may provide effective light sedation and is associated with fewer sedation-related adverse effects in burn patients. Sedation with dexmedetomidine during the weaning process in adult burn patients was associated with lower delirium rates, a trend towards the earlier withdrawal of mechanical ventilation but did not seem to improve the total duration of mechanical ventilation.

Amelioration of myocardial ischemia/reperfusion injury in diabetes: A narrative review of the mechanisms and clinical applications of dexmedetomidine

Mechanisms contributing to the pathogenesis of myocardial ischemia-reperfusion (I/R) injury are complex and multifactorial. Many strategies have been developed to ameliorate myocardial I/R injuries based on these mechanisms. However, the cardioprotective effects of these strategies appear to diminish in diabetic states. Diabetes weakens myocardial responses to therapies by disrupting intracellular signaling pathways which may be responsible for enhancing cellular resistance to damage. Intriguingly, it was found that Dexmedetomidine (DEX), a potent and selective α2-adrenergic agonist, appears to have the property to reverse diabetes-related inhibition of most intervention-mediated myocardial protection and exert a protective effect. Several mechanisms were revealed to be involved in DEX’s protection in diabetic rodent myocardial I/R models, including PI3K/Akt and associated GSK-3β pathway stimulation, endoplasmic reticulum stress (ERS) alleviation, and apoptosis inhibition. In addition, DEX could attenuate diabetic myocardial I/R injury by up-regulating autophagy, reducing ROS production, and inhibiting the inflammatory response through HMGB1 pathways. The regulation of autonomic nervous function also appeared to be involved in the protective mechanisms of DEX. In the present review, the evidence and underlying mechanisms of DEX in ameliorating myocardial I/R injury in diabetes are summarized, and the potential of DEX for the treatment/prevention of myocardial I/R injury in diabetic patients is discussed.

Outcomes of dexmedetomidine versus propofol sedation in critically ill adults requiring mechanical ventilation: a systematic review and meta-analysis of randomised controlled trials

BACKGROUND

Guidelines have recommended the use of dexmedetomidine or propofol for sedation after cardiac surgery, and propofol monotherapy for other patients. Further outcome data are required for these drugs.

METHODS

This systematic review and meta-analysis was prospectively registered on PROSPERO. The primary outcome was ICU length of stay. Secondary outcomes included duration of mechanical ventilation, ICU delirium, all-cause mortality, and haemodynamic effects. Intensive care patients were analysed separately as cardiac surgical, medical/noncardiac surgical, those with sepsis, and patients in neurocritical care. Subgroup analyses based on age and dosage were conducted.

RESULTS

Forty-one trials (N=3948) were included. Dexmedetomidine did not significantly affect ICU length of stay across any ICU patient subtype when compared with propofol, but it reduced the duration of mechanical ventilation (mean difference -0.67 h; 95% confidence interval: -1.31 to -0.03 h; P=0.041; low certainty) and the risk of ICU delirium (risk ratio 0.49; 95% confidence interval: 0.29-0.87; P=0.019; high certainty) across cardiac surgical patients. Dexmedetomidine was also associated with a greater risk of bradycardia across a variety of ICU patients. Subgroup analyses revealed that age might affect the incidence of haemodynamic side-effects and mortality among cardiac surgical and medical/other surgical patients.

CONCLUSION

Dexmedetomidine did not significantly impact ICU length of stay compared with propofol, but it significantly reduced the duration of mechanical ventilation and the risk of delirium in cardiac surgical patients. It also significantly increased the risk of bradycardia across ICU patient subsets.

Dexmedetomidine vs other sedatives in critically ill mechanically ventilated adults: a systematic review and meta-analysis of randomized trials

Conventional gabaminergic sedatives such as benzodiazepines and propofol are commonly used in mechanically ventilated patients in the intensive care unit (ICU). Dexmedetomidine is an alternative sedative that may achieve lighter sedation, reduce delirium, and provide analgesia. Our objective was to perform a comprehensive systematic review summarizing the large body of evidence, determining if dexmedetomidine reduces delirium compared to conventional sedatives. We searched MEDLINE, EMBASE, CENTRAL, ClinicalTrials.gov and the WHO ICTRP from inception to October 2021. Independent pairs of reviewers identified randomized clinical trials comparing dexmedetomidine to other sedatives for mechanically ventilated adults in the ICU. We conducted meta-analyses using random-effects models. The results were reported as relative risks (RRs) for binary outcomes and mean differences (MDs) for continuous outcomes, with corresponding 95% confidence intervals (CIs). In total, 77 randomized trials (n = 11,997) were included. Compared to other sedatives, dexmedetomidine reduced the risk of delirium (RR 0.67, 95% CI 0.55 to 0.81; moderate certainty), the duration of mechanical ventilation (MD - 1.8 h, 95% CI  - 2.89 to  - 0.71; low certainty), and ICU length of stay (MD  - 0.32 days, 95% CI  - 0.42 to  - 0.22; low certainty). Dexmedetomidine use increased the risk of bradycardia (RR 2.39, 95% CI 1.82 to 3.13; moderate certainty) and hypotension (RR 1.32, 95% CI 1.07 to 1.63; low certainty). In mechanically ventilated adults, the use of dexmedetomidine compared to other sedatives, resulted in a lower risk of delirium, and a modest reduction in duration of mechanical ventilation and ICU stay, but increased the risks of bradycardia and hypotension.

A comparative study of sedo-analgesic effect of dexmedetomidine and dexmedetomidine with ketamine in postoperative mechanically ventilated patients

Background and Aims:

To compare the sedoanalgesic effects of dexmedetomidine alone or with combination of ketamine.

Material and Methods:

After getting ethical approval and informed patient consent, 60 adult surgical patients, were randomly divided into two groups. Group KD (n = 30); received dexmedotomidine 0.5 μg/kg/h mixed with ketamine 0.5 μg/kg/h and Group DEX (n = 30); received dexmedotomidine at 0.5 mg/kg/h infusion only. In both the groups, study drugs were titrated (dexmedetomidine- 0.2-0.7 μg/kg/h and ketamine 0.2-0.7 mg/kg/h) to achieve target sedation. Hemodynamic variables, pain scores, sedation scores, and patient satisfaction were recorded. Qualitative and Quantitative data were analyzed with Pearson Chi-squared test and analysis of variance test, respectively. All analyses were done by using statistical package for social sciences (SPSS) version 16.0.

Results:

Pain scores were higher in group DEX than in group KD at 2 h and 4 h which was statistically significant (P < 0.05). At the end of 2 h, sedation scores were higher in group KD than in group DEX and was statistically significant (P < 0.05). Length of intensive care unit stay was almost comparable in both groups, and the time to tracheal extubation was lesser in ketamine-dexmedetomidine group as compared to the dexmedetomidine alone group. However the difference was statistically non-significant.

Conclusions:

By combining dexmedetomidine with ketamine we observed lower incidence of hypotension and bradycardia. Dexmedetomidine with ketamine combination therapy could be used safely and effectively as sedo-analgesic agent.

Comparison of Intra and Post-operative Sedation efficacy of Dexmedetomidine-Midazolam and Dexmedetomidine-Propofol for Major Abdominal Surgery

BACKGROUND

The effectiveness and side effects of dexmedetomidine (DEX) in combination with midazolam and propofol have not been comparatively studied in a single clinical trial as sedative agents to general anesthesia before.

OBJECTIVE

The objective of this study is to compare intra and post-operative sedation between DEX-Midazolam and DEX-Propofol in patients who underwent major abdominal surgery on the duration of general anesthesia, hemodynamic and sedation effect.

METHOD

This prospective, randomized, double-blinded clinical trial included 50 patients who were 20 to 60 years of age and admitted for major abdominal surgery. The patients were randomly assigned by a computer-generated random numbers table to sedation with DEX plus midazolam (DM group) (n=25) or DEX plus propofol (DP group) (n=25). In the DM group, patients received a bolus dose of 0.1 mg/kg of midazolam and immediately initiated the intravenous (i.v.) infusion of DEX 1 µg/kg over a 10 min and 0.5 µg/kg/hr by continuous i.v. infusion within operation period. In the DP group, patients received pre-anesthetic i.v. DEX 1 µg/kg over 15 min before anesthesia induction and 0.2-1 µg/kg/hr by continuous i.v. infusion during the operative period. After preoxygenation for at least 2 min, during the surgery, patients received propofol infusion dose of 250 μg/kg/min for 15 min then a basal infusion dose of 50 μg/kg/min. The bispectral index (BIS) value, as well as mean arterial pressure (MAP), heart rate (HR), respiratory rate (RR), oxygen saturation (SaO2), percutaneous arterial oxygen saturation (SpO2) and end-tidal carbon dioxide tension (ETCO2) were recorded before anesthesia (T0), during anesthesia (at 15-min intervals throughout the surgical procedure), by a blinded observer. Evidence of apnea, hypotension, hypertension and hypoxemia were recorded during surgery.

RESULTS

The hemodynamic changes, including HR, MAP, BIS, VT, SaO2, and RR had a downward tendency with time, but no significant difference was observed between the groups (P>0.05). However, the two groups showed no significant differences in ETCO2 and SPO2 values in any of the assessed interval (P>0.05). In this study, the two groups showed no significant differences in the incidence of nausea, vomiting, coughing, apnea, hypotension, hypertension, bradycardia and hypoxemia (P>0.05). Respiratory depression and serious adverse events were not reported in either group. Extubation time after surgery was respectively 6.3 ± 1.7 and 5.8 ± 1.4 hr. in the DM and DP groups and the difference was not statistically significant (P= 0.46).

CONCLUSION

Our study showed no significant differences between the groups in hemodynamic and respiratory changes in each of the time intervals. There were also no significant differences between the two groups in the incidence of complication intra and post-operative. Further investigations are required to specify the optimum doses of using drugs which provide safety in cardiovascular and respiratory system without adverse disturbance during surgery.

Impact of intravenous dexmedetomidine on postoperative bowel movement recovery after laparoscopic nephrectomy: A consort-prospective, randomized, controlled trial

BACKGROUND

Postoperative ileus is a frequent postoperative complication, especially after abdominal surgery. Sympathetic excitation is the primary factor for postoperative ileus. Sympathetic activation becomes increased by surgical stress, postoperative pain, and inflammation. Dexmedetomidine (DEX) can inhibit sympathetic nerve activity, inflammation, and pain.

AIM

To observe whether DEX promotes bowel movements in patients after laparoscopic nephrectomy.

METHODS

One hundred and twenty patients undergoing laparoscopic nephrectomy were assigned to three groups: C (normal saline infusion), D1 (DEX 0.02 µg/kg/h), and D2 (DEX 0.04 µg/kg/h). The primary outcomes were the recorded times to first flatus, defecation, and eating after surgery. The secondary outcomes were postoperative pain, assessed using the numerical rating scale (NRS), adverse effects, and the duration of the postoperative hospital stay.

RESULTS

The times to first flatus, defecation, and eating in groups D1 and D2 were significantly shorter than those in group C (P < 0.01). The NRS scores at 8 h and 24 h after surgery were significantly lower in groups D1 and D2 than in group C (P < 0.05). No adverse effects were observed (P > 0.05).

CONCLUSION

Postoperative infusion of DEX at 0.04 µg/kg/h facilitates bowel movements in patients undergoing laparoscopic nephrectomy.

Inhibitory Effects of Dexmedetomidine and Propofol on Gastrointestinal Tract Motility Involving Impaired Enteric Glia Ca2+ Response in Mice

Propofol and dexmedetomidine are popular used for sedation in ICU, however, inadequate attention has been paid to their effect on gastrointestinal tract (GIT) motility. Present study aimed to compare the effect of propofol and dexmedetomidine on GIT motility at parallel level of sedation and explore the possible mechanism. Male C57BL/6 mice (8-10 weeks) were randomly divided into control, propofol and dexmedetomidine group. After intraperitoneal injection of propofol or dexmedetomidine, comparable sedative level was confirmed by sedative score, physiological parameters and electroencephalogram (EEG). Different segments of GIT motility in vivo (gastric emptying, small intestine transit, distal colon bead expulsion, stool weight and number of fecal pellets, gastrointestinal transit and whole gut transit time) and colonic migrating motor complexes (CMMCs) pattern in vitro were evaluated. The Ca2+ response of primary enteric glia was examined under the treatment of propofol or dexmedetomidine. There is little difference in physiological parameters and composite permutation entropy index (CPEI) between administration of 50 mg/kg propofol and 40 μg/kg dexmedetomidine, indicated that parallel level of sedation was reached. Data showed that propofol and dexmedetomidine had significantly inhibitory effect on GIT motility while dexmedetomidine was stronger. Also, the amplitude (ΔF/F0) of Ca2+ response in primary enteric glia was attenuated after treated with the sedatives while the effect of dexmedetomidine was greater than propofol. These findings demonstrated that dexmedetomidine caused stronger inhibitory effects on GIT motility in sedative mice, which may involve impaired Ca2+ response in enteric glia. Hence, dexmedetomidine should be carefully applied especially for potential GIT dysmotility patient.

Hemodynamic Adverse Effects of Dexmedetomidine and Propofol in a Critically Ill Trauma and Surgical Population: A Retrospective Cohort

BACKGROUND

Propofol and dexmedetomidine may cause hemodynamic adverse effects (AEs) and more data are needed in a trauma and surgical population.

OBJECTIVE

The objective of this study was to evaluate the rate of hemodynamic AEs requiring an intervention between dexmedetomidine and propofol in a critically ill trauma and surgical population.

METHODS

This was a retrospective cohort study at a Level 1 trauma center. Intensive care unit patients admitted from October 1, 2017, through October 31, 2018, were divided into two groups: dexmedetomidine or propofol. The primary end point was the proportion of patients who required a therapeutic intervention for a hemodynamic AE within the first 24 hr of initiation of dexmedetomidine or propofol.

RESULTS

A total of 800 charts were reviewed and 85 patients (dexmedetomidine [n = 35] and propofol [n = 50]) were included. The study population consisted of Caucasian (86%) males (61%) with a median age of 61 [interquartile range-IQR 48, 72], and 18% and 24% required antihypertensive and vasopressor agents, respectively. No difference in the primary outcome was observed (17 [49%] vs. 27 [54%], p = .624). There was no difference in the overall incidence of hemodynamic AE (18 [51%] vs. 30 [60%], p = .433). Dexmedetomidine patients had a greater decrease in median heart rate (HR) compared with the propofol (23 [IQR 16, 41] vs. 14 [IQR 5, 24] beats/min, p = .002).

CONCLUSIONS

The rate of hemodynamic AEs requiring therapeutic interventions was similar between dexmedetomidine and propofol in a critically ill trauma and surgical population; however, dexmedetomidine may be associated with a larger decrease in HR.

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.

Optimizing Pain Control and Minimizing Opioid Use in Trauma Patients

Adverse effects of opioids and the ongoing crisis of opioid abuse have prompted providers to reduce prescribing opioids and increase use of multiple nonpharmacologic therapies, nonopioid analgesics, and co-analgesics for pain management in trauma patients. Nonopioid agents, including acetaminophen, nonsteroidal anti-inflammatory drugs, gabapentinoids, ketamine, central α2 agonists, and lidocaine, can be used as adjuncts or alternatives to opioids in the trauma population. Complementary therapies such as acupuncture, virtual reality, and mirror therapy are modalities that also may be helpful in reducing pain. Performing pain assessments is fundamental to identify pain and evaluate treatment effectiveness in the critically ill trauma patient. The efficacy, safety, and availability of opioid-sparing therapies and multimodal pain regimens are reviewed.

Dexmedetomidine sedation for endobronchial ultrasound-guided transbronchial needle aspiration, a randomised controlled trial

Background and aim

Appropriate sedation is important to the success of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA). Dexmedetomidine is a sedative agent that operates via the α2 adrenergic agonist, which provides sleep-like sedation with little respiratory suppression. This study compared the efficacy and safety of dexmedetomidine sedation with propofol in cases of EBUS-TBNA.

Methods

Patients requiring EBUS-TBNA were randomly assigned dexmedetomidine sedation (D, n=25) or propofol sedation (P, n=25). Vital signs, diagnostic yield and the bispectral index (BIS) were recorded throughout the bronchoscopic procedure and recovery period. The tolerance and cooperation of the patients were evaluated using questionnaires.

Measurements and results

The lowest mean arterial blood pressure in group D (79.2±9.9 versus 72.5±12.9 mmHg, p=0.049) exceeded that in group P, the lowest heart rate was lower (60.9±10.2 versus 71.4±11.8 beats·min⁻¹, p=0.006) and the mean BIS during sedation was significantly higher (84.1±8.3 versus 73.6±5.7, p<0.001). Patients in group D were more likely to report perceiving procedure-related symptoms and express an unwillingness to undergo the bronchoscopy again, if indicated (41.1 versus 83.3%, p=0.007). One subject in group D aborted EBUS-TBNA due to intolerance. Many of the variables in the two groups were similar, including the proportion of hypoxaemic events, recovery times, patient cooperation and diagnostic yield.

Conclusions

The effects of dexmedetomidine on haemodynamics were in line with its pharmacodynamic features. Patients who received dexmedetomidine were more likely than those who received propofol to perceive the procedures. Overall, dexmedetomidine did not prove inferior to propofol sedation in terms of patient cooperation or diagnostic yield.

Compared to propofol sedation for EBUS-TBNA, dexmedetomidine provided patients lighter sedation with lower heart rates and less decrease in blood pressure. The recovery times, hypoxaemia, cooperation and diagnostic yield in the two groups were similar.https://bit.ly/33qgEj3

Guidelines for sedation in gastroenterological endoscopy (second edition)

Sedation in gastroenterological endoscopy has become an important medical option in routine clinical care. Here, the Japan Gastroenterological Endoscopy Society and the Japanese Society of Anesthesiologists together provide the revised "Guidelines for sedation in gastroenterological endoscopy" as a second edition to address on-site clinical questions and issues raised for safe examination and treatment using sedated endoscopy. Twenty clinical questions were determined and the strength of recommendation and evidence quality (strength) were expressed according to the "MINDS Manual for Guideline Development 2017." We were able to release up-to-date statements related to clinical questions and current issues relevant to sedation in gastroenterological endoscopy (henceforth, "endoscopy"). There are few reports from Japan in this field (e.g., meta-analyses), and many aspects have been based only on a specialist consensus. In the current scenario, benzodiazepine drugs primarily used for sedation during gastroenterological endoscopy are not approved by national health insurance in Japan, and investigations regarding expense-related disadvantages have not been conducted. Furthermore, including the perspective of beneficiaries (i.e., patients and citizens) during the creation of clinical guidelines should be considered. These guidelines are standardized based on up-to-date evidence quality (strength) and supports on-site clinical decision-making by patients and medical staff. Therefore, these guidelines need to be flexible with regard to the wishes, age, complications, and social conditions of the patient, as well as the conditions of the facility and discretion of the physician.

Effect of dexmedetomidine on delirium during sedation in adult patients in intensive care units: A systematic review and meta-analysis

STUDY OBJECTIVE

To compare the effect of sedation protocols with and without dexmedetomidine on delirium risk and duration in adult patients in intensive care units (ICUs).

DESIGN

A meta-analysis of randomized controlled trials.

REVIEW METHODS

We searched the Cochrane Central Register of Controlled Trials, PubMed, EMBASE, and ISI Web of Science from inception to September 3, 2020. We included studies comparing the effect of dexmedetomidine-based sedation on delirium risk with non-dexmedetomidine-based sedation in adult patients in ICUs. We pooled the data using a random-effects model using Review Manager 5.2, and assessed publication bias using Stata 11.0. The quality of evidence was rated using the Grading of Recommendations, Assessment, Development and Evaluation system.

MAIN RESULTS

We included 36 studies involving 9623 participants. The use of dexmedetomidine was associated with reduced risk of delirium (risk ratio [RR], 0.63; 95% confidence interval [CI], 0.54-0.75; very low-quality evidence), but higher incidences of hypotension and bradycardia during hospital stay. Dexmedetomidine was also associated with shorter durations of ICU stay, hospital stay and mechanical ventilation. Dexmedetomidine did not affect ICU mortality (RR, 1.01; 95% CI, 0.89-1.14; low-quality evidence), hospital mortality (RR, 1.01; 95% CI, 0.91-1.12; very low-quality evidence), or 30-day mortality (RR, 0.77; 95% CI, 0.58-1.01; moderate-quality evidence), or duration of delirium (mean difference, -0.74 days; 95% CI, -1.83 to 0.36 days; very low-quality evidence). We identified publication bias for risk and duration of delirium, length of ICU stay, and hospital stay.

CONCLUSIONS

Low- or very low-quality evidence suggests that dexmedetomidine was associated with a clinically-small reduction of delirium risk, ICU/hospital stay and mechanical ventilation duration, but were not associated with improved mortality or shorter delirium duration in ICU patients. These findings were inconclusive because of publication bias, heterogeneity, and limited sample size. Significant adverse effects of dexmedetomidine include hypotension and bradycardia. PROSPERO registration number: CRD42018095358.

Dexmedetomidine-remifentanil vs propofol-remifentanil for monitored anesthesia care during hysteroscopy: Randomized, single-blind, controlled trial

BACKGROUND

Although dexmedetomidine has been used as either the anesthetic agent for light sedation or as an adjunct to other sedatives, no study has investigated the usefulness of dexmedetomidine as the main sedative agent for invasive and painful procedures. The purpose of this study was to compare the safety of dexmedetomidine-remifentanil and propofol-remifentanil during monitored anesthesia care (MAC) for hysteroscopy.

METHODS

Female patients undergoing hysteroscopy were randomly assigned to either the dexmedetomidine (group D) or the propofol group (group P). The study drug (0.6 ml/kg; dexmedetomidine 2 μg/ml or propofol 4 mg/ml) was loaded for 10 minutes followed by 0.1 to 0.5 ml/kg/hour to maintain a bispectral index of 60 to 80 during the procedure. In both groups, remifentanil was infused using a target-controlled-infusion system with a target concentration of 2 ng/ml and titrated during the procedure. The incidence rates of intraoperative respiratory depression in both groups were compared. Postoperative pain and patients satisfaction were also compared.

RESULTS

A total of 69 female patients were included in this study. Dexmedetomidine significantly decrease the incidence of respiratory depression compared with propofol (15/34 [44.1%] vs 5/35 [14.3%], P = .006, group P and D, respectively). Postoperative pain and patients satisfaction score did not differ between the groups.

CONCLUSION

The combination of dexmedetomidine-remifentanil can reduce the incidence of respiratory depression without increasing hemodynamic complications compared with propofol-remifentanil for MAC during hysteroscopy.

Dexmedetomidine Is an Equal Cost Alternative to Propofol in Transcatheter Aortic Valve Replacement, With Equivalent In-Hospital and 30-Day Outcomes

OBJECTIVE

Transcatheter aortic valve replacement (TAVR) with monitored anesthesia care (MAC) is well-tolerated and is growing in popularity. Differences in outcomes based on anesthetic agent choice with MAC has received less attention. The authors sought to determine whether differences in outcomes and cost exist based on whether patients receive dexmedetomidine or propofol when undergoing TAVR with MAC.

DESIGN

Retrospective cohort study.

SETTING

The Penn State Milton S. Hershey Medical Center, Hershey, Pennsylvania.

PARTICIPANTS

The study comprised 161 patients who underwent TAVR with MAC between May 2014 and March 2019.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

A propofol-only (n = 58) group and dexmedetomidine-only (n = 103) group were identified. No differences in in-hospital mortality or complication rate were identified when evaluating for stroke, transfusion, new arrhythmia, cardiac arrest, or bleeding and vascular complications (p > 0.05, all). Thirty-day outcomes were also equivalent, with no differences in mortality, stroke, vascular complication, new arrhythmia, or myocardial infarction (p > 0.05, all). The average amount of epinephrine, norepinephrine, or phenylephrine used intraoperatively was not significantly different. Overall median hospitalization costs were equivalent ($57,554.31 with dexmedetomidine v $58,538.08 with propofol, p = 0.97).

CONCLUSIONS

There were no significant differences in in-hospital outcomes, 30-day outcomes, or total cost of the patient's hospitalization, based on the use of dexmedetomidine versus propofol in patients undergoing TAVR.

Assessment of the sedative effects of dexmedetomidine and propofol treatment in patients undergoing mechanical ventilation in the ICU and relationship between treatment and occurrence of ventilator-associated pneumonia and detection of pathogenic bacteria

The present study aimed to investigate the sedative effects of dexmedetomidine combined with propofol in patients undergoing mechanical ventilation in the intensive care unit (ICU), and to reveal the risk factors of ventilator-associated pneumonia (VAP). A retrospective analysis of 322 patients who had been subject to mechanical ventilation in the ICU ward was performed. Subjects were divided into two groups: A group treated with dexmedetomidine and propofol (combined group) and a group treated with dexmedetomidine alone (monotherapy group). Clinical data, sedative effects, the number of VAP patients and the distribution of VAP pathogens were assessed. Multivariate analysis and receiver operating characteristic (ROC) curves were used to predict VAP. Significant differences in the sedative effects between the two groups were observed (P<0.001). The incidence of VAP was significantly higher in the monotherapy group compared with the combined group (P<0.05). Multivariate logistic regression analysis demonstrated that age, acute physiology chronic health evaluation score, consciousness, invasive operations, recovery time, extubation time and sedation regimen were independent risk factors for VAP in the ICU during mechanical ventilation. ROC curves indicated that the areas under the curve for age, acute physiology chronic health score, consciousness, invasive operations, recovery time, extubation time and sedation regimen were 0.934, 0.870, 0.632, 0.677, 0.865, 0.950 and 0.603, respectively. In summary, dexmedetomidine combined with propofol can shorten the recovery and extubation times of mechanical ventilation patients in the ICU. Different sedation schemes are also independent risk factors for VAP during mechanical ventilation in the ICU.

Effects of spinal anesthesia and sedation with dexmedetomidine or propofol on cerebral regional oxygen saturation and systemic oxygenation a period after spinal injection

PURPOSE

To evaluate changes in cerebral regional oxygen saturation (rSO₂) after spinal anesthesia and compare the changes in rSO₂ and systemic oxygenation between dexmedetomidine sedation and propofol sedation.

METHODS

Thirty-six patients scheduled to undergo transurethral surgery under spinal anesthesia were randomly assigned to the dexmedetomidine (n = 18) and propofol groups (n = 18). We used near-infrared spectroscopy sensors to measure rSO₂, and obtained data from each side were averaged. After oxygen insufflation, baseline measurements of mean arterial blood pressure (MAP), heart rate, rSO₂, pulse oximetry saturation (SpO₂), bispectral index, and body temperature were made. After spinal anesthesia, we measured these parameters every 5 min. Twenty minutes after spinal injection, dexmedetomidine or propofol administration was started. We measured each parameter at 10, 25, and 40 min after the administration of dexmedetomidine or propofol.

RESULTS

The baseline rSO₂ in the dexmedetomidine group was 71.3 ± 7.3%, and that in the propofol group was 71.8 ± 5.6%. After spinal anesthesia, rSO₂ in both groups decreased significantly (dexmedetomidine group: 65.4 ± 6.9%; propofol group: 64.3 ± 7.4%). After administering sedatives, rSO₂ was equivalent after spinal anesthesia. rSO₂ was comparable between the two groups. MAP and SpO₂ were significantly higher in the dexmedetomidine group than in the propofol group.

CONCLUSION

Spinal anesthesia decreased rSO₂; however, the decline was not severe. Dexmedetomidine and propofol did not compromise cerebral oxygenation under spinal anesthesia. Nevertheless, MAP and SpO₂ were more stable in dexmedetomidine sedation than in propofol sedation. Dexmedetomidine may be suitable for spinal anesthesia.

Hemodynamic Effects of Dexmedetomidine in Adults With Reduced Ejection Fraction Heart Failure

BACKGROUND

Dexmedetomidine (DEX) can cause hypotension complicating its use in critically ill patients with labile hemodynamics secondary to an underlying disease state such as heart failure. The aim of this study was to determine the effect of DEX on mean arterial pressure (MAP) in nonsurgical patients with heart failure and reduced ejection fraction (HFrEF).

METHODS

This retrospective single-center cohort study evaluated patients who received DEX in the cardiac care and medical intensive care units at a large academic hospital. The primary end point was the change in MAP within 6 hours following DEX initiation.

RESULTS

Sixty-five patients with HFrEF diagnosis were compared 1:1 to a control group without HFrEF. Both groups experienced a decrease in MAP over the study period. Patients with HFrEF had a greater absolute percentage reduction in MAP 1 hour following DEX initiation compared to the control group (-9.6% vs -5.2%; P < .01). When accounting for the combined effect of DEX initiation and HFrEF diagnosis on the primary end point, patients with HFrEF did not have a significant difference in MAP compared to the control group over the study period.

CONCLUSIONS

Within 6 hours following DEX initiation, both groups experienced a decrease in MAP. The effect of DEX on MAP over the composite time period was not found to be significantly different in the HFrEF group compared to the non-HFrEF group. However, patients with HFrEF experienced a greater reduction in MAP in the first hour following DEX initiation compared to the non-HFrEF group. Prospective studies are needed to evaluate the effect of DEX on patients with acute decompensated HFrEF compared to patients with compensated HFrEF.

The (Un)Conscious Mouse as a Model for Human Brain Functions: Key Principles of Anesthesia and Their Impact on Translational Neuroimaging

In recent years, technical and procedural advances have brought functional magnetic resonance imaging (fMRI) to the field of murine neuroscience. Due to its unique capacity to measure functional activity non-invasively, across the entire brain, fMRI allows for the direct comparison of large-scale murine and human brain functions. This opens an avenue for bidirectional translational strategies to address fundamental questions ranging from neurological disorders to the nature of consciousness. The key challenges of murine fMRI are: (1) to generate and maintain functional brain states that approximate those of calm and relaxed human volunteers, while (2) preserving neurovascular coupling and physiological baseline conditions. Low-dose anesthetic protocols are commonly applied in murine functional brain studies to prevent stress and facilitate a calm and relaxed condition among animals. Yet, current mono-anesthesia has been shown to impair neural transmission and hemodynamic integrity. By linking the current state of murine electrophysiology, Ca2+ imaging and fMRI of anesthetic effects to findings from human studies, this systematic review proposes general principles to design, apply and monitor anesthetic protocols in a more sophisticated way. The further development of balanced multimodal anesthesia, combining two or more drugs with complementary modes of action helps to shape and maintain specific brain states and relevant aspects of murine physiology. Functional connectivity and its dynamic repertoire as assessed by fMRI can be used to make inferences about cortical states and provide additional information about whole-brain functional dynamics. Based on this, a simple and comprehensive functional neurosignature pattern can be determined for use in defining brain states and anesthetic depth in rest and in response to stimuli. Such a signature can be evaluated and shared between labs to indicate the brain state of a mouse during experiments, an important step toward translating findings across species.

Efficacy of combination therapy with dexmedetomidine for benzodiazepines-induced disinhibition during endoscopic retrograde cholangiopancreatography

BACKGROUND

Benzodiazepines (BZDs) and analgesics are widely used for conscious sedation during endoscopic ultrasound (EUS) or endoscopic retrograde cholangiopancreatography (ERCP). However, endoscopic procedures are sometimes discontinued because of BZD-induced disinhibitory reactions such as excessive movement. We evaluated the usefulness of dexmedetomidine (DEX) for BZD-induced disinhibition in ERCP.

METHODS

Between February 2018 and August 2019, 22 patients who underwent EUS or ERCP were enrolled. All patients showed BZD-induced excessive movement at the first examination (BZD group) and received DEX at the second examination (DEX group). The initial DEX dose was 6 μg/kg/h for a 10-min loading, followed by 0.4 μg/kg/h during the procedure. BZDs and analgesics were administered before scope insertion. An additional sedative was administered to achieve a Ramsay sedation scale (RSS) of 4-5. Sedative effect, procedure completion rate, and changes in circulatory and respiratory dynamics were evaluated.

RESULTS

Mean RSS scores were significantly higher (p < 0.001) in the DEX (5.1 ± 0.5) compared with the BZD (4.0 ± 0.5) group. The movement score (p < 0.001) and number of additional sedatives required (p < 0.01) were lower in the DEX group. The procedure completion rate was significantly higher in the DEX (95.5%) compared with the BZD group (63.6%; p < 0.05). Significant differences in the frequency of hypotension (p = 1.00), bradycardia (p = 0.22), and respiratory depression (p = 0.68) were not noted between groups.

CONCLUSIONS

The addition of DEX to BZD therapy yielded better sedative efficacy, lower excessive movement, a reduction in BZDs used, and a higher procedure complete rate. DEX may be used as an alternative method for BZD-induced inhibition during ERCP.

Examination of the sedative and analgesic effects of gabapentin and dexmedetomidine in patients undergoing laparoscopic cholecystectomy surgery: A randomized controlled trial

Introduction:

At present, laparoscopic surgery is a very common method, especially for the removal of the gallbladder, because pain and anxiety following surgery is a major problem in surgical operations. Various studies have demonstrated the effectiveness of gabapentin and dexmedetomidine in reducing pain intensity after surgery. The present study is aimed at examining the sedative and analgesic effects of gabapentin and dexmedetomidine in patients undergoing laparoscopic cholecystectomy.

Methods:

This was a double-blinded clinical trial involving 40 patients who were candidates for laparoscopic cholecystectomy. The patients were randomly allotted in two groups of dexmedetomidine (n = 20) and gabapentin (n = 20). Then, pain intensity based on the visual analog scale (VAS) and sedation level based on the Ramsay Sedation Scale (RSS) were measured at the curtained times. As the data were not normally distributed, the Mann–Whitney U test was used to analyze the data, and the significance level was set at 0.05.

Results:

Across the follow-up points, more reduction in pain intensity was observed in the dexmedetomidine group as compared with the gabapentin group. The available dissimilarities between these two groups in pain decrement at the recovery room and 3 h after being discharged from the recovery room were not significant (P ≥ 0.414). In addition, across all the time points, there was considerable growth in sedation in the dexmedetomidine group in comparison with the gabapentin group (P < 0.024). This finding indicated that dexmedetomidine was more effective than gabapentin in creating sedation.

Conclusion:

Compared with gabapentin, dexmedetomidine leads to more pain reduction after surgery and better sedation during and after surgery.

Earlier tracheostomy is associated with an earlier return to walking, talking, and eating

BACKGROUND

Conjecture remains regarding the optimal timing for tracheostomy. Most studies examine patient mortality, ventilation duration, intensive care unit (ICU) length of stay, and medical complications. Few studies examine patient-centric outcomes. The aim of this study was to determine whether timing of tracheostomy had an impact on length of stay, morbidity, mortality, and patient-centric outcomes towards their functional recovery.

METHODS

This prospective observational study included data for all tracheostomised patients over 4 y in a tertiary ICU. The study time period commenced with the insertion of an endotracheal tube. Data collected included patient and disease specifics; mortality up to 4 y; mobility scores; and time to oral intake, talking, and out-of-bed exercises. To assess differences between timing of tracheostomy, a survival analysis was conducted to dynamically compare patients on days before and after tracheostomy tube (TT) placement during their ICU admission.

RESULTS

TT was placed in 276 patients. After tracheostomy, the patients were able to (on average) verbally communicate 7.4 d earlier (confidence interval [CI] = -9.1 to -4.9), return to oral intake 7.0 d earlier (CI = -10 to -4.6), and perform out-of-bed exercises 6.2 d earlier (CI = -8.4 to -4) than those who did not yet have a TT. In patients with an endotracheal tube, none were able to talk or have oral intake, and the majority (99%) did not participate in out-of-bed exercises/active rehabilitation. After tracheostomy, patients subsequently received significantly less analgesic and sedative drugs and more antipsychotics. No clear differences in ICU and long-term mortality were associated with tracheostomy timing.

CONCLUSIONS

Earlier tracheostomy is associated with earlier achievement of patient-centric outcomes - patients returning to usual daily activities such as talking, out-of-bed mobility, and eating/drinking significantly earlier, whilst also receiving less sedatives and analgesics.

A prospective randomized double-blinded study of dexmedetomidine versus propofol infusion for orbital surgeries

PURPOSE

Orbital surgeries are traditionally taken up under general anesthesia. Local anesthesia combined with moderate sedation can also be considered as an alternative option. This study was performed to compare the safety and efficacy of dexmedetomidine and propofol infusion for orbital surgeries under local anesthesia.

METHODS

Twenty patients undergoing orbital surgery by a single surgeon were enrolled in this prospective randomized study. Selected patients were randomly administered dexmedetomidine (Group D) or propofol (Group P). Hemodynamic and respiratory effects, sedation levels, recovery profile, analgesic properties, and satisfaction levels of the patients and the surgeon were assessed.

RESULTS

There was a significant decrease in mean arterial pressures following drug administration compared to initial measurements in both the groups. However, a statistically significant decrease in heart rate was observed only in Group P. The sedation score at the end of loading dose was 3.3 ± 0.82 in Group D and 2.5 ± 0.52 in Group P and this difference was also statistically significant (P value-0.027). The surgeon's satisfaction score was 6.5 ± 0.71 in Group D and 5.6 ± 1.07 in Group P (P value - 0.045). There were no statistically significant differences observed in patients' satisfaction, pain, and anxiety scores in either group. No major hemodynamic changes or complications were noted in either of the groups.

CONCLUSION

Dexmedetomidine, in comparison to propofol, provides better sedation levels with good hemodynamic stability. It also offers better surgeon satisfaction, thus providing a useful alternative for general anesthesia in selective patients undergoing orbital surgery.

Optimising the dose of clonidine to achieve sedation in intensive care unit patients with population pharmacokinetics

Aims

The aim of this study was to investigate the population pharmacokinetics (PK) of clonidine in intensive care unit (ICU) patients in order to develop a dosing regimen for sedation.

Methods

We included 24 adult mechanically ventilated, sedated patients from a mixed medical and surgical ICU. Intravenous clonidine was added to standard sedation in doses of 600, 1200 or 1800 μg/d. Within each treatment group, 4 patients received a loading dose of half the daily dose administered in 4 hours. Patients gave an average of 12 samples per individual. In total, 286 samples were available for analysis. Model development was conducted with NONMEM and various covariates were tested. After modelling, doses to achieve a target steady‐state plasma concentration of >1.5 μg/L were explored using stochastic Monte Carlo simulations for 1000 virtual patients.

Results

A 2‐compartment model was the best fit for the concentration‐time data. Clearance (CL) increased linearly with 0.213%/h; using allometric scaling, body weight was a significant covariate on the central volume of distribution (V1). Population PK parameters were: CL 17.1 (L/h), V1 124 (L/70 kg), intercompartmental CL 83.7 (L/h), and peripheral volume of distribution 178 (L), with 33.3% CV interindividual variability on CL and 66.8% CV interindividual variability on V1. Simulations revealed that a maintenance dose of 1200 μg/d provides target sedation concentrations of >1.5 μg/L in 95% of the patients.

Conclusion

A population PK model for clonidine was developed in an adult ICU. A dosing regimen of 1200 μg/d provided a target sedation concentration of >1.5 μg/L.

The influence of dexmedetomidine and propofol on circulating cytokine levels in healthy subjects

Background

Surgery and diseases modify inflammatory responses and the immune system. Anesthetic agents also have effects on the human immune system but the responses they induce may be altered or masked by the surgical procedures or underlying illnesses. The aim of this study was to assess how single-drug dexmedetomidine and propofol anesthesia without any surgical intervention alter acute immunological biomarkers in healthy subjects.

Methods

Thirty-five healthy, young male subjects were anesthetized using increasing concentrations of dexmedetomidine (n = 18) or propofol (n = 17) until loss of responsiveness (LOR) was detected. The treatment allocation was randomized. Multi-parametric immunoassays for the detection of 48 cytokines, chemokines and growth factors were used. Concentrations were determined at baseline and at the highest drug concentration for each subject.

Results

The changes in the concentration of eotaxin (decrease after dexmedetomidine) and platelet-derived growth factor (PDGF, increase after propofol) were statistically significantly different between the groups. Significant changes were detected within both groups; the concentrations of monocyte chemotactic protein 1, chemokine ligand 27 and macrophage migration inhibitory factor were lower in both groups after the drug administration. Dexmedetomidine decreased the concentration of eotaxin, interleukin-18, interleukin-2Rα, stem cell factor, stem cell growth factor and vascular endothelial growth factor, and propofol decreased significantly the levels of hepatocyte growth factor, IFN-γ-induced protein 10 and monokine induced by IFN-γ, and increased the levels of interleukin-17, interleukin-5, interleukin-7 and PDGF.

Conclusions

Dexmedetomidine seemed to have an immunosuppressive effect on the immune system whereas propofol seemed to induce mixed pro- and anti-inflammatory effects on the immune system. The choice of anesthetic agent could be relevant when treating patients with compromised immunological defense mechanisms.

Trial registration

Before subject enrollment, the study was registered in the European Clinical Trials database (EudraCT number 2013–001496-21, The Neural Mechanisms of Anesthesia and Human Consciousness) and in ClinicalTrials.gov (Principal Investigator: Harry Scheinin, number NCT01889004, The Neural Mechanisms of Anesthesia and Human Consciousness, Part 2, on the 23rd of June 2013).

The comparison of dexmedetomidine, esmolol, and combination of dexmedetomidine with esmolol for attenuation of sympathomimetic response to laryngoscopy and intubation in patients undergoing coronary artery bypass grafting

Background:

The aim of this study was to compare the effects of dexmedetomidine, esmolol, and combination of both on control of sympathetic response to laryngoscopy and tracheal intubation in coronary artery disease patients.

Material and Methods:

A prospective, randomized, double-blinded clinical study included 90 patients scheduled for elective coronary artery bypass surgery. Patients were randomly allocated into three groups of 30 each: dexmedetomidine group (Group D) 1 μg/kg, esmolol group (Group E) 2 mg/kg, and group dexmedetomidine with esmolol (Group DE) 0.5 μg/kg of dexmedetomidine with 1 mg/kg of esmolol. Each drug was diluted with 0.9% normal saline to 20 ml volume and infused in 10 min before induction of anesthesia. Hemodynamic changes (heart rate [HR], arterial blood pressure, and pulmonary artery pressure) were compared at various time intervals as follows-baseline, after study drug, after induction, and 1, 3, and 5 min after intubation. Statistical analysis included analysis of variance, Chi-square, and Fisher's exact test.

Results:

In Group DE, there was no significant increase in HR at all-time intervals, and the HR was stable compared to Group D and Group E. Blood pressure values were comparable in all groups except in Group E at 5 min. The pulmonary arterial pressures were statistically less in DE group except at 3 and 5 min.

Conclusions:

The combination of dexmedetomidine and esmolol group has beneficial effect on HR and pulmonary arterial pressures but has no additional advantage with respect to arterial blood pressure when compared with dexmedetomidine and esmolol groups in patients undergoing elective coronary artery bypass grafting.

The Effect of Dexmedetomidine on Oral Mucosal Blood Flow and the Absorption of Lidocaine

Dexmedetomidine (DEX) is a sedative and analgesic agent that acts via the alpha-2 adrenoreceptor and is associated with reduced anesthetic requirements, as well as attenuated blood pressure and heart rate in response to stressful events. A previous study reported that cat gingival blood flow was controlled via sympathetic alpha-adrenergic fibers involved in vasoconstriction. In the present study, experiment 1 focused on the relationship between the effects of DEX on alpha adrenoreceptors and vasoconstriction in the tissues of the oral cavity and compared the palatal mucosal blood flow (PMBF) in rabbits between general anesthesia with sevoflurane and sedation with DEX. We found that the PMBF was decreased by DEX presumably because of the vasoconstriction of oral mucosal vessels following alpha-2 adrenoreceptor stimulation by DEX. To assess if this vasoconstriction would allow decreased use of locally administered epinephrine during DEX infusion, experiment 2 in the present study monitored the serum lidocaine concentration in rabbits to compare the absorption of lidocaine without epinephrine during general anesthesia with sevoflurane and sedation with DEX. The depression of PMBF by DEX did not affect the absorption of lidocaine. We hypothesize that this is because lidocaine dilates the blood vessels, counteracting the effects of DEX. In conclusion, despite decreased palatal blood flow with DEX infusion, local anesthetics with vasoconstrictors should be used in implant and oral surgery even with administered DEX.

Sedatives, analgesics and antipsychotics in tracheostomised ICU patients - Is less more?

BACKGROUND

Sedation and anaesthesia are used universally to facilitate mechanical ventilation - with larger cumulative doses being used in those with prolonged ventilation. Transitioning from an endotracheal to a tracheostomy tube enables the depth of sedation to be reduced. Early use of speaking valves with tracheostomised patients has become routine in some intensive care units (ICU). The return of verbal communication has been observed to improve ease of patient care and increase patient and family engagement, with a perceived reduction in patient agitation.

OBJECTIVES

To investigate the potential impact of speaking valve (SV) use on requirements of sedatives, analgesics and antipsychotics in ICU patients with a tracheostomy.

METHODS

A retrospective data audit was undertaken for all tracheostomised patients in a cardio-respiratory ICU from 2011 to 2014. Use of sedative, analgesic and antipsychotic drugs was captured for endotracheal tube, tracheostomy and SV periods, including patient demographics, disease specifics and severity. Stratified Cox regression analysis was performed to determine the effects of SV on drug dosage.

RESULTS

Of 257 patients, 144 (56%) received an SV. Use of an SV was associated with reduced risk of being in the upper quartile of daily dosage of analgesics (HR: 0.6; 95% CI: 0.5-0.8; p < 0.001). In the final adjusted multivariable model, analgesic dose was additionally associated with age, and attendance to operating theatre during ICU. Sedative dose was associated with age, gender and SOFA score. Antipsychotic dose was associated with gender (less likely in females: HR 0.6, 95% CI: 0.4-0.8), age and APACHE score.

CONCLUSIONS

There was significantly less analgesic used in patients with an SV compared to those without. However, SV use in patients with tracheostomy was not found to be associated with reduced dose of sedatives or antipsychotics, despite the clinical impression. Future prospective studies are needed to more adequately investigate the association between drugs and patients' ability to verbally participate in their care.

Dexmedetomidine: present and future directions

Dexmedetomidine is a potent, highly selective α-2 adrenoceptor agonist, with sedative, analgesic, anxiolytic, sympatholytic, and opioid-sparing properties. Dexmedetomidine 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. Dexmedetomidine may produce less delirium than other sedatives or even prevent delirium. The analgesic effect of dexmedetomidine is not strong; however, it can be administered as a useful analgesic adjuvant. As an anesthetic adjuvant, dexmedetomidine decreases the need for opioids, inhalational anesthetics, and intravenous anesthetics. The sympatholytic effect of dexmedetomidine may provide stable hemodynamics during the perioperative period. Dexmedetomidine-induced cooperative sedation with minimal respiratory depression provides safe and acceptable conditions during neurosurgical procedures in awake patients and awake fiberoptic intubation. Despite the lack of pediatric labelling, dexmedetomidine has been widely studied for pediatric use in various applications. Most adverse events associated with dexmedetomidine occur during or shortly after a loading infusion. There are some case reports of dexmedetomidine-related cardiac arrest following severe bradycardia. Some extended applications of dexmedetomidine discussed in this review are promising, but still limited, and further research is required. The pharmacological properties and possible adverse effects of dexmedetomidine should be well understood by the anesthesiologist prior to use. Moreover, it is necessary to select patients carefully and to determine the appropriate dosage of dexmedetomidine to ensure patient safety.

Adjusted vs Total Body Weight-Based Dosing of Sedation and Analgesia Used in the Intensive Care Unit

Background: The purpose of this study was to evaluate if dosing fentanyl, dexmedetomidine, and propofol based on ideal or adjusted vs actual weight in patients would decrease overall opioid and sedative use. Methods: This was a retrospective chart review comparing adjusted vs actual weight-based dosing protocol of mechanically ventilated (MV) intensive care unit (ICU) adult patients who required fentanyl and either propofol or dexmedetomidine. Results: A total of 261 patients were included in which 101 patients were in the actual weight group and 160 patients were in the adjusted weight group. Total doses per MV day of fentanyl was 1042 ± 1060 µg in the actual weight group vs 901 ± 1025 µg in the adjusted weight group (P = .13). Total doses per MV day of midazolam was 20 ± 19 mg in the actual group vs 15 ± 19 mg adjusted group (P = .02). Average MV days was 8.2 vs 7.1 days, ICU length of stay was 10.6 vs 9.4 days, and self-extubation rates were 17.8% vs 4.4% in the actual group and adjusted group, respectively. Conclusion: Total midazolam doses per MV day were lower in the adjusted group. No significant change was seen in MV days, ICU length of stay, or self-extubation rates.

Region specific differences in the effect of propofol on the murine colon result in dysmotility

Propofol is the most widely used intravenous anaesthetic agent for maintenance of anaesthesia and sedation. Studies in varying regions of the bowel have shown conflicting differences on the effects of propofol on motility. There the aim of this study was to understand the influence of propofol on colonic function and explore by which mechanism any changes occur. Functional studies were conducted using isolated colonic tissue from C57BL6 mice which were exposed to 5 μM propofol. Faecal pellet motility, colonic migratory motor complexes (CMMCs) and functional bioassays were utilised to monitor colonic function and nitric oxide production was monitored by amperometry. There was a signficant reduction in amplitude of CMMCs in the distal colon in the presence of 5 μM propofol, however no difference was observed in the proximal colon. A signficant increase in the 5-HT evoked contractions were observed in distal colon in the presence of 5 μM propofol. Additionally, a reduction in the NO production in the presence of 5 μM propofol was only observed in the distal colon. As a result, in the presence of 5 μM propofol, faecal pellet transit was increased, and velocity was reduced. At clinically relevant doses, propofol was shown to reduce colonic motility by inhibiting nitric oxide synthase in only the distal region of the colon. Our findings indicate that propofol has a considerable influence on colonic signalling mechanisms and impairs colonic motility, which may have implications in its clinical use especially for maintenance.

Efficacy of Adding Low-Dose Ketamine to Dexmedetomidine Versus Low-Dose Ketamine and Propofol for Conscious Sedation in Patients Undergoing Awake Fiber-optic Intubation

Background and Aims:

Conscious sedation is the key for successful AFOI. This trial was conducted to compare the effectiveness of dexmedetomidine and low dose of ketamine against propofol and low dose ketamine.

Materials and Methods:

Sixty patients subjected for general anesthesia were invited to participate in the study and randomly allocated into two equal groups: D-K (n = 30) had been received a bolus dose of both ketamine 0.5mg /kg and dexmedetomidine 1ug/kg over 10 min. Then continuous infusion of ketamine 0.5mg /kg and dexmedetomidine 1ug/kg. The second group (P-K group) (n = 30): had been received a bolus dose of both ketamine 0.5mg/kg and propofol 1mg/kg over 10 min. Then continuous infusion of ketamine 0. 5mg/kg and propofol 1mg/kg.

Results:

The intubation time was statistically significant shorter within the D-K group (58.9 ± 6.1) versus P-K group (63.4 ± 5.3) with p-value 0.02. The shorter time needed to achieve the OAA/S score = 2 was in the D-K group (2.25 ± 0.75) versus (2.9 ± 0.79) in P-K group with (P-value 0.004). The intubation scores were insignificant different between both groups except vocal cord opening which was statistical better among D-K group with P-value 0.03. The significant hypotensive recorded data were among P-K group while the decreased heart rate were recorded in D-K group. Eighty percentages of patients had excellent score of satisfaction within the D-K gp against 47% among the patients within P-K gp with P-value 0.01.

Conclusion:

The concomitant administration of low dose of ketamine with dexmedetomidine had better intubation time and sedation scores with higher patient satisfaction scores than the combination of propofol and low dose of ketamine.

Pharmacologic Considerations Surrounding Sedation, Delirium, and Sleep in Critically Ill Adults: A Narrative Review

INTRODUCTION

Agitation, delirium, and sleep dysfunction in the intensive care unit (ICU) are common occurrences that result in negative patient outcomes. With the recent publication of the 2018 Clinical Practice Guidelines for the Prevention and Management of Pain, Agitation/Sedation, Delirium, Immobility, and Sleep Disruption in Adult Patients in the ICU (PAD-IS), several areas are of particular interest due to emerging literature or conflicting results of research.

OBJECTIVE

To highlight areas where emerging literature or variable study results exist and to provide the clinician with recommendations regarding patient management.

METHODS

The 2018 PAD-IS guidelines were reviewed, and areas of emerging literature or lack of consensus of included investigations surrounding pharmacologic management of sedation, delirium, and sleep in the ICU were identified. A review and appraisal of the literature was conducted specifically to address the identified areas. Prospective, randomized trials were included in this narrative review.

RESULTS

Four areas with emerging data or conflicting evidence were identified and included: use of propofol or dexmedetomidine for sedation, pharmacologic prevention of delirium, treatment of delirium, and pharmacologic strategies to improve sleep.

CONCLUSION

A comprehensive approach to the prevention and management of delirium, sedation, and sleep in the ICU is necessary to optimize patient outcomes.

Sedative drugs used for mechanically ventilated patients in intensive care units: a systematic review and network meta-analysis

BACKGROUND

The effects of different sedative drugs on all-cause mortality rate, duration of ICU stay, and risk of delirium in mechanically ventilated ICU patients are unclear. This meta-analysis aimed to compare the effectiveness and safety of individual sedative drugs and drug combinations in mechanically ventilated ICU patients.

MATERIALS AND METHODS

Medline, Embase, Cochrane, EBSCOhost, and ISI Web of Science databases were searched for studies that assessed sedation in ICU mechanically ventilated patients. A Bayesian random-effects model was used to combine the direct comparisons and indirect evidence.

RESULTS

Thirty-one randomized, controlled trials were included, which consisted of 4491 patients who received one of seven sedative drugs or a combination of drugs. There were no significant differences regarding the all-cause mortality rate. Compared to propofol, inhalation anesthetics (hazard ratio [HR] 0.121; 95% credible interval [CrI] -7.58 to 7.62), alpha agonists (HR 2.2; 95% CrI 0.776 to 5.22), propofol with benzodiazepines (HR 0.306; 95% CrI -6.97 to 7.65), ketamine with benzodiazepines (HR 6.57; 95% CrI -6.05 to 19.1) and placebo (HR 2.4; 95% CrI -5.37 to 10.3), benzodiazepines (HR 3.62; 95% CrI 0.834 to 6.2) may increase the duration of ICU stay. Compared to alpha agonists, propofol (HR 2.4; 95% CrI 0.304 to 21.1) and placebo (HR 6.12; 95% CrI 0.745 to 54.6), benzodiazepines (HR 2.59; 95% CrI 1.08 to 7.4) were associated with incremental risks of delirium.

CONCLUSION

Compared to propofol, benzodiazepines may increase the duration of ICU stay. Compared to alpha agonists, benzodiazepines were associated with an increased risk of delirium.

Comparison of dexmedetomidine and benzodiazepine for intraoperative sedation in elderly patients: a randomized clinical trial

Background and objectives

Elderly individuals have a greater sensitivity to sedation, and the most commonly used drugs for sedation are benzodiazepines, which exhibit some complication. Therefore, this study aimed to compare the use of dexmedetomidine and midazolam regarding proper sedation and postoperative complications in elderly individuals who require intraoperative sedation.

Methods

This study was a parallel-randomized clinical trial, which included 120 patients aged >70 years undergoing regional anesthesia and sedation. The exclusion criteria consisted of bradycardia, heart failure, respiratory failure, a Glasgow Coma Scale ≤14, liver failure and refusal to participate. Patients were divided into two groups: the first group received midazolam (MDZ), while the second group received dexmedetomidine (DEX). The doses were titrated to achieve an intraoperative Richmond Agitation-Sedation Scale (RASS) score between −3 and −1. Incidences of complications were recorded.

Results

During a 120 min follow-up, the depth of sedation (RASS score) revealed variations less often in the DEX group (p=0.002). Patients in the DEX group (n=67) had lower rates of intraoperative complications (19.4% vs 73.6%, p<0.001). Intraoperatively, the incidence rates of psychomotor agitation (15.1% vs 1.5%, p=0.005), arterial hypotension (28.3% vs 3.0%, p<0.001) and respiratory depression (73.6% vs 0%, p<0.001) were higher in the MDZ group (n=53). During postanesthesia care, the incidence rates of shivering (p<0.001), residual sedation (p=0.04) and use of supplemental oxygen (p<0.001) were significantly lower in the DEX group.

Conclusions

The use of DEX for sedation during surgery provides better control over the depth of sedation and produces fewer complications in elderly individuals.

Trial registration number

NCT02878837.

Difficult Extubation: Calming the Sympathetic Storm

Tracheal extubation can evoke an equally strong haemodyamic stress response as tracheal intubation. We present a patient with myocardial infarction who repeatedly failed tracheal extubation. He developed acute pulmonary oedema following each attempt at tracheal extubation due to sympathetic overactivity. A change of approach with extubation under propofol sedation followed by continued sympatholysis with dexmedetomidine infusion allowed successful extubation.

Dexmedetomidine Infusion without Loading Dose in Surgical Patients Requiring Mechanical Ventilation: Haemodynamic Effects and Efficacy

We investigated the haemodynamic effects and the efficacy of a continuous infusion of dexmedetomidine without a loading dose in 50 patients having had cardiac surgery (n=33), complex major surgery (n=9) and multiple trauma (n=8). The mean age was 60 (±16) years, and the mean APACHE II score was 13 (±5). Dexmedetomidine was commenced at an initial rate of 0.2 to 0.4 μg/kg/h (depending on whether anaesthetic or sedative agents had already been used) and rescue analgesia and sedation was administered with morphine and midazolam respectively. Propofol was used if additional sedation was needed. Sedation was targeted to a modified Motor Activity Assessment Score. Eighty percent of patients required no or “minimal” rescue therapy (<10 mg midazolam /day and/or <10 mg morphine/day and/or <100 mg propofol/day). The cardiac surgery group needed the least rescue therapy. A statistically significant but clinically unimportant reduction in mean heart rate and mean systolic blood pressure was observed over the first six hours (P<0.0001, and P=0.009 respectively). The baseline heart rate of 85 (±17) beats per minute (bpm), fell to a low of 78 (±13) bpm at four hours and then remained stable throughout the infusion period. The systolic blood pressure fell from 125 (±22) mmHg to a low of 112 (±20) mmHg at 1.5 hours with minimal change afterwards.

Dexmedetomidine was an effective sedative and analgesic in this group of complex surgical and trauma patients with pronounced benefit in the cardiac surgery group. Omitting the loading dose avoided undesirable haemodynamic effects without compromising sedation and analgesia.