Dexmedetomidine–ketamine and midazolam–ketamine combinations for sedation in pediatric patients undergoing extracorporeal shock wave lithotripsy: a randomized prospective study

Dexmedetomidine-ketamine combination versus fentanyl-midazolam for patient sedation during flexible bronchoscopy: a prospective, single-blind, randomized controlled trial

BACKGROUND

Sedation during flexible bronchoscopy (FB) should maintain an adequate respiratory drive, ensure maximum comfort for the patient, and warrant that the objectives of the procedure are achieved. Nevertheless, the optimal sedation method for FB has yet to be established. This study aimed to compare the standard recommended combination of midazolam-fentanyl (MF) with that of dexmedetomidine-ketamine (DK) for patient sedation during FB.

METHODS

Patients subjected to FB were randomly assigned to a DK (n = 25) and an MF group (n = 25). The primary outcome was the rate of critical desaturation events (arterial oxygen saturation < 80% with nasal oxygen supply 2 L/min). Secondary outcomes included sedation depth, hemodynamic complications, adverse events, and patient and bronchoscopist satisfaction.

RESULTS

The incidence rates of critical desaturation events were similar between the two groups (DK: 12% vs. MF: 28%, p = 0.289). DK achieved deeper maximum sedation levels (higher Ramsay - lower Riker scale; p < 0.001) and was associated with longer recovery times (p < 0.001). Both groups had comparable rates of hemodynamic and other complications. Patient satisfaction was similar between the two groups, but bronchoscopist satisfaction was higher with the DK combination (p = 0.033).

CONCLUSION

DK demonstrated a good safety profile in patients subjected to FB and achieved more profound sedation and better bronchoscopist satisfaction than the standard MF combination without increasing the rate of adverse events.

Efficacy and safety of ketamine alone and ketamine-dexmedetomidine combination for sedation for brain computed tomography in paediatric patients with head injuries: A retrospective study

OBJECTIVE

To compare the efficacy and safety of ketamine alone with those of ketamine-dexmedetomidine combination for sedation during brain CT in paediatric patients with head injuries.

METHODS

We retrospectively analysed the data of paediatric patients who underwent sedation for brain CT at the ED. We included patients aged 6 months to 6 years with American Society of Anesthesiologists physical status I or II. The sedative protocol involved the administration of intramuscular (IM) ketamine 3 mg/kg (K), ketamine 2 mg/kg with dexmedetomidine 1.5 μg/kg (KD) or ketamine 1.5 mg/kg with dexmedetomidine 1.5 μg/kg (low-KD). The primary and secondary outcomes were sedation failure and adverse events, respectively.

RESULTS

We included 77 patients; among them, 28, 23 and 26 were in the K, KD and low-KD groups, respectively. In multivariable analysis, the combination groups (KD and low-KD groups) were significantly associated with a lower possibility of sedation failure compared to the K group (adjusted odds ratio, 0.12; 95% confidence interval, 0.02-0.56). Moreover, there were no significant differences in adverse events between the groups, and the sedation-related time variables also did not significantly differ among the three groups.

CONCLUSIONS

Our findings indicated that a combination of IM ketamine-dexmedetomidine provides effective sedation for paediatric patients undergoing brain CT without significant adverse events. Further research is needed to investigate the potential benefits of using lower doses of ketamine in combination.

Comparison of the Effectiveness of Dexmedetomidine-Ketamine and Midazolam-Ketamine Regimens in Sedation of Children Treated with Extracorporeal Shock Wave Lithotripsy

Background

Despite the high acceptability of the extracorporeal shock wave lithotripsy (ESWL) procedure in the treatment of urinary stones at all ages, it is necessary to use a variety of analgesic drugs during the procedure, especially among children.

Objectives

We aimed to evaluate the effect of dexmedetomidine-ketamine (DK) and midazolam-ketamine (MK) compounds in the sedation of children (2-6 years old) undergoing ESWL.

Methods

This randomized, double-blind clinical trial was performed on children aged 2 to 6 years with renal stones undergoing ESWL. The participants were randomly assigned to the DK and MK regimen groups (dexmedetomidine, 0.05 mcg/kg within 10 minutes infusion; midazolam, 0.05 mg/kg within 3 minutes infusion; ketamine, 0.5 mg/kg bolus injection). The patients were assessed with respect to sedation degree, post-procedure hemodynamic status, recovery time and awakening, and operator satisfaction.

Results

Recovery time was significantly shorter in the DK group than in the MK group. Also, the DK regimen was more analgesic than the MK regimen; therefore, the need to repeat ketamine administration was less. There was no difference between the 2 methods in terms of cooperation at the time of separation of children from their parents, patient cooperation during the procedure, average verbal response time and average cooperation time after entering recovery, and operator satisfaction with the operation. No side effects were observed in the 2 groups.

Conclusions

Ketamine with dexmedetomidine is associated with greater analgesia and shorter recovery time; however, sedation time was longer (insignificant) in ketamine with midazolam than in ketamine with dexmedetomidine. Thus, ketamine with dexmedetomidine is more preferred.

Uncovering the Benefits of the Ketamine-Dexmedetomidine Combination for Procedural Sedation during the Italian COVID-19 Pandemic

This retrospective observational study evaluated the safety and efficacy of the ketamine and dexmedetomidine combination (keta-dex) compared to ketamine or dexmedetomidine alone for sedation of patients with acute respiratory distress due to COVID-19 pneumonia who require non-invasive ventilation. The following factors were assessed: tolerance to the ventilation, sedation level on the Richmond Agitation-Sedation Scale (RASS), hemodynamic and saturation profile, adverse effects, and discontinuation or mortality during ventilation. The study included 66 patients who underwent sedation for non-invasive ventilation using keta-dex (KETA-DEX group, n = 22), ketamine (KET group, n = 22), or dexmedetomidine (DEX group, n = 22). The DEX group showed a slower sedation rate and a significant reduction in blood pressure compared to the KETA-DEX group (p < 0.05). An increase in blood pressure was recorded more frequently in the KET group. No reduction in oxygen saturation and no deaths were observed in any of the groups. None of the patients discontinued ventilation due to intolerance. The mean duration of sedation was 28.12 h. No cases of delirium were observed in any of the groups. Overall, keta-dex was associated with faster sedation rates and better hemodynamic profiles compared to dexmedetomidine alone. Keta-dex is effective and safe for sedation of uncooperative patients undergoing non-invasive ventilation.

Dexmedetomidine for sedation during epicardial ablation for ventricular tachycardia: a single-center experience

BACKGROUND

Epicardial approach to ventricular tachycardia (VT) ablation is mainly performed under general anesthesia (GA). Although catheter manipulation and ablation in the epicardial space could be painful, GA lowers blood pressure and may interfere with arrhythmia induction and mapping, and the use of muscle relaxants precludes identification of the phrenic nerve (PN). Moreover, an anesthesiologist's presence is required during GA for the whole procedure, which may not always be possible. Therefore, we evaluated the feasibility and safety of epicardial VT ablations performed under conscious sedation using dexmedetomidine in our center.

METHODS

Between January 2018 and January 2022, all patients who underwent epicardial VT ablation under continuous dexmedetomidine infusion were prospectively included in the study. All patients received premedication 30 min before the epicardial puncture with paracetamol (acetaminophen 10 mg/ml) 1000 mg and ketorolac 30 mg. Sedation protocol included an intravenous bolus of midazolam hydrochloride (0.03-0.05 mg/kg) followed by continuous infusion of dexmedetomidine (0.2-0.7 mcg/kg/h). In addition, an intravenous fentanyl citrate bolus (0.7-1.4 mcg/kg) was given for short-term analgesia, followed by a second dose repeated after 30 to 45 min. Sedation-related complications were defined in case of respiratory failure, severe hypotension, and bradycardia requiring treatment.

RESULTS

Sixty-nine patients underwent epicardial or endo-epi VT ablation under conscious sedation and were included in the analysis. The mean age was 65.4 ± 12.1 years; forty-six patients were males (66.6%). All patients had drug-refractory recurrent VT. Forty-seven patients (68.1%) had non-ischemic cardiomyopathy (NICM), 13 patients (18.9%) had ischemic-cardiomyopathy (ICM), and 9 patients (13%) had myocarditis. Standard percutaneous sub-xiphoid access was attempted in all patients. Non-inducibility of any VT was achieved in 82.6% (9/9 myocarditis, 10/13 ICM, 38/47 NICM, n = 57/69 patients), inducibility of non-clinical VT in 13% (3/13 ICM, 6/38 NICM, n = 9/69 patients), and failure in 4.3% (3/38 NICM, n = 3/69 patients). Although we observed procedural-related complications in five patients (7.2%), one transient PN palsy, two pericarditis, and two vascular complications, those were not related to the conscious sedation protocol. No respiratory failure, severe hypotension, or bradycardia requiring treatment has been observed among the patients.

CONCLUSIONS

Prompt availability of anesthesiology support remains crucial for complex procedures such as epicardial VT ablation. Continuous infusion of dexmedetomidine and administration of midazolam and fentanyl seem to be a safe and effective sedation protocol in patients undergoing epicardial VT ablation.

Dexmedetomidine in combination with ketamine for pediatric procedural sedation or premedication: A meta-analysis

OBJECTIVE

To evaluate effectiveness of combinational use of dexmedetomidine and ketamine (DEX-KET) for pediatric procedural sedation or premedication.

METHODS

Relevant studies were identified after a literature search in electronic databases and study selection was based on precise eligibility criteria. Meta-analyses of mean differences were performed to examine differences in sedation onset and recovery times between DEX-KET and comparators. Changes from baseline in heart rate (HR), respiratory rate, oxygen saturation, and mean arterial pressure (MAP), were pooled. Meta-analyses of proportions were performed to estimate incidence of adverse events.

RESULTS

15 studies (1087 patients) were included. Onset of sedation was significantly shorter in DEX-KET than in DEX group. HR declined in DEX-KET group from start (-3.5 beats per minute (BPM) [95% CI: -5.1, -1.9]) through midpoint (-7.2 BPM [95% CI: -12.1, -2.3]) and at end of sedation (-8.7 BPM [95% CI: -13.1, -4.4]). Decrease in HR after DEX administration at start was -11.6 BPM [95% CI: -16.0, -7.1] and remained consistent afterward. There was no change in MAP during DEX-KET sedation. However, after DEX administration, MAP decreased by -6.9 [95% CI: -10.4, -3.3] at start, -7.8 [95% CI: -11.4, -4.2] at middle, and by -6.6 [95% CI: -14.4, 1.1] at end of sedation. Incidence of hypotension was 3% [95% CI: 0, 9] in DEX-KET, 7% [95% CI: 2, 14] in DEX, and 0% [95% CI: 0, 2] in KET groups. Incidence of bradycardia was 2% [95% CI: 0, 6] with DEX-KET and 12% [95% CI: 5, 20] with DEX. Incidence of oxygen desaturation was 3% [95% CI: 0, 8] in DEX-KET, 2% [95% CI: 0, 6] in DEX, 12% [95% CI: 5, 20] in KET, and 13% [95% CI: 6, 21] in PROP-KET groups. MIDA-KET sedation had 13% [95% CI: 4, 25] incidence of tachycardia.

CONCLUSIONS

DEX-KET for pediatric sedation results in better sedation outcomes than DEX or KET by shortening onset of sedation and recovery while maintaining hemodynamic and respiratory stability with low incidence of adverse events. DEX sedation was associated with higher incidence of bradycardia. Higher incidence of oxygen desaturation was observed with KET and PROP-KET whereas MIDA-KET was associated with higher incidence of tachycardia.

[Propofol-ketamine versus dexmedetomidine-ketamine for sedation during upper gastrointestinal endoscopy in pediatric patients: a randomized clinical trial]

BACKGROUND AND OBJECTIVES

Day-case pediatric sedation is challenging. Dexmedetomidine is a sedative analgesic that does not induce respiratory depression. We compared dexmedetomidine to propofol when it was added to ketamine for sedation during pediatric endoscopy, regarding recovery time and hemodynamic changes.

METHODS

We enrolled 120 patients (2-7 years in age) and randomly assigned them into two groups. Each patient received intravenous (IV) ketamine at a dose of 1 mg.kg^-1 in addition to either propofol (1 mg.kg^-1) or dexmedetomidine (0.5 μg.kg^-1). The recovery time was compared. Hemodynamics, oxygen saturation, need for additional doses, postoperative complications and endoscopist satisfaction were monitored.

RESULTS

There was no significant difference in hemodynamics between the groups. The Propofol-Ketamine (P-K) group showed significantly shorter recovery times than the Dexmedetomidine-Ketamine (D-K) group (21.25 and 29.75 minutes respectively, p <0.001). The P-K group showed more oxygen desaturation. Eleven and six patients experienced SpO₂ <92% in groups P-K and D-K, respectively. A significant difference was noted regarding the need for additional doses; 10% of patients in the D-K group needed one extra dose, and 5% needed two extra doses, compared to 25% and 20% in the P-K group, respectively (p=0.001). The P-K group showed less post-procedure nausea and vomiting. No statistically significant difference between both groups regarding endoscopist satisfaction.

CONCLUSIONS

The P-K combination was associated with a shorter recovery time in pediatric upper gastrointestinal endoscopy, while the D-K combination showed less need for additional doses.

REGISTRATION NUMBER

Clinical trials.gov (NCT02863861).

Effects on the Upper Airway Morphology with Intravenous Addition of Ketamine after Dexmedetomidine Administration in Normal Children

General anesthesia decreases the tone of upper airway muscles in a dose-dependent fashion, potentially narrowing the pharyngeal airway. We examined the effects of adding ketamine on the airway configuration after dexmedetomidine administration in spontaneously breathing children with normal airways. 25 children presenting for Magnetic Resonance Imaging (MRI) of the brain/spine under general anesthesia were prospectively recruited in the study. Patients were anesthetized with dexmedetomidine bolus (2 mcg over 10 min) followed by dexmedetomidine infusion (2 mcg·kg−1·h) and ketamine and permitted to breathe spontaneously via the native airway. MR-CINE images of the upper airway were obtained with dexmedetomidine infusion alone (baseline) and 5, 10, and 15 min after administering ketamine bolus (2 mg·kg−1) in two anatomical axial planes at the nasopharynx and the retroglossal upper airway. Airway lumen is segmented with a semi-automatic image processing approach using a region-growing algorithm. Outcome measures of cross-sectional area, transverse and anterior-posterior diameters of the airway in axial planes at the level of the epiglottis in the retroglossal airway, and in the superior nasopharynx were evaluated for changes in airway size with sedation. Airway dimensions corresponding to the maximum, mean, and minimum sizes during a respiratory cycle were obtained to compare the temporal changes in the airway size. The dose-response of adding ketamine to dexmedetomidine alone condition on airway dimensions were examined using mixed-effects of covariance models. 22/25 patients based on inclusion/exclusion criteria were included in the final analysis. The changes in airway measures with the addition of ketamine, when compared to the baseline of dexmedetomidine alone, were statistically insignificant. The modest changes in airway dimensions are clinically less impactful and within the accuracy of the semi-automatic airway segmentation approach. The effect sizes were small for most airway measures. The duration of ketamine seems to not affect the airway size. In conclusion, adding ketamine to dexmedetomidine did not significantly reduce upper airway configuration when compared to dexmedetomidine alone.

Propofol-ketamine versus dexmedetomidine-ketamine for sedation during upper gastrointestinal endoscopy in pediatric patients: a randomized clinical trial

Background and objectives

Day-case pediatric sedation is challenging. Dexmedetomidine is a sedative analgesic that does not induce respiratory depression. We compared dexmedetomidine to propofol when it was added to ketamine for sedation during pediatric endoscopy, regarding recovery time and hemodynamic changes.

Methods

We enrolled 120 patients (2−7 years in age) and randomly assigned them into two groups. Each patient received intravenous (IV) ketamine at a dose of 1 mg.kg^-1 in addition to either propofol (1 mg.kg^-1) or dexmedetomidine (0.5 μg.kg^-1). The recovery time was compared. Hemodynamics, oxygen saturation, need for additional doses, postoperative complications and endoscopist satisfaction were monitored.

Results

There was no significant difference in hemodynamics between the groups. The Propofol-Ketamine (P-K) group showed significantly shorter recovery times than the Dexmedetomidine-Ketamine (D-K) group (21.25 and 29.75 minutes, respectively, p < 0.001). The P-K group showed more oxygen desaturation. Eleven and 6 patients experienced SpO₂ < 92% in groups P-K and D-K, respectively. A significant difference was noted regarding the need for additional doses; 10% of patients in the D-K group needed one extra dose, and 5% needed two extra doses, compared to 25% and 20% in the P-K group, respectively (p =  0.001). The P-K group showed less post-procedure nausea and vomiting. No statistically significant difference between both groups regarding endoscopist satisfaction.

Conclusions

The P-K combination was associated with a shorter recovery time in pediatric upper gastrointestinal endoscopy, while the D-K combination showed less need for additional doses.

Registration number

Clinical trials.gov (NCT02863861).

The pearls of pediatric sedation: polish the old and embrace the new

Over the past decade, as the complexity and breadth of pediatric procedures increases, the actual choices of approved sedatives have remained relatively stagnant. Since the introduction of midazolam, there has not been a sedative approved for pediatric labelling until December 2018. This December, the European approval of ADV6209 (Ozalin) for pediatric usage marked the newest addition to the pediatric sedative armamentarium in over a decade. This review is timely and significant because it will provide a balanced evaluation of the most common sedatives in use today, the most recent sedative to be approved and, most importantly, a critical look at the literature supporting the latest approaches to the most commonly performed procedures.

Application of dexmedetomidine-remifentanil in high-intensity ultrasound ablation of uterine fibroids: a randomised study

OBJECTIVE

To compare the effects of dexmedetomidine-remifentanil with the traditional analgesia and sedation regimen midazolam-remifentanil during HIFU treatment of uterine fibroids.

DESIGN

A randomised controlled trial.

SETTING

Department of Anesthesia in a single hospital.

POPULATION

Patients with uterine fibroids.

METHODS

A total of 80 patients diagnosed with uterine fibroids and scheduled for selective HIFU treatment were randomly divided into the dexmedetomidine group (the D group) and midazolam group (the M group). At 20 minutes before the HIFU procedure, patients in the D group received a loading dose of 0.8 μg/kg dexmedetomidine, followed by a continuous intravenous infusion of 0.2 μg/kg/hour until the end of the operation. Patients in the M group were given a corresponding amount of 0.9% saline. Patients in the M group received a slow intravenous infusion of 0.03 mg/kg midazolam before the procedure, an intravenous injection of 0.02 mg/kg 30 minutes later, another 0.02 mg/kg 60 minutes later, followed by 0.02 mg/kg at 40-minutes intervals. Patients in the D group were given a corresponding amount of 0.9% saline. During the HIFU procedure, patients in both groups were administered remifentanil at an effect site concentration of 1.0 ng/ml. Sedation and analgesia were rated using the Ramsay Sedation Scale (RSS) and Visual Analogue Scale (VAS) before drug administration (T1), after drug administration but before HIFU (T2), at the beginning of HIFU (T3), 15 minutes later (T4), 45 minutes later (T5), 75 minutes later (T6), and at the end of HIFU (T7). Patient satisfaction score and Steward recovery score survey were conducted 30 minutes after surgery.

MAIN OUTCOME MEASURES

Different effects of the traditional midazolam-remifentanil regimen and dexmedetomidine-remifentanil.

RESULTS

All patients in both groups underwent a successful HIFU procedure without developing serious complications during the postoperative period. However, the D group reported significantly fewer cases of respiratory depression than the M group during HIFU treatment (P < 0.05). The pause during HIFU ablation in the D group was significantly shorter than that in the M group. HIFU ablation intensity, the number of patients with an RSS of 3 or 4 measured at different time points, and the number of patients with an RSS of 3 or 4 measured at arousal were significantly greater in the D than the M group (P < 0.05). Likewise, the D group scored significantly higher in the evaluation of patient satisfaction, recovery score, and surgeon satisfaction (P < 0.05).

CONCLUSIONS

Both dexmedetomidine-remifentanil and midazolam-remifentanil met the requirements and ensured the safety of HIFU treatment of uterine fibroids. However, compared with the traditional midazolam-remifentanil regimen, dexmedetomidine-remifentanil was associated with more stable sedation in patients, more efficient HIFU treatment and higher degree of patient comfort.

TWEETABLE ABSTRACT

Dexmedetomidine-remifentanil is associated with more stable sedation in patients, more efficient HIFU treatment and higher degree of patient comfort than is midazolam-remifentanil.

Analysis of 17 948 pediatric patients undergoing procedural sedation with a combination of intranasal dexmedetomidine and ketamine

BACKGROUND

Intranasal procedural sedation using dexmedetomidine is well described in the literature. The combination of intranasal dexmedetomidine and ketamine is a novel approach for which there are little data on the rate of successful sedation or adverse events.

OBJECTIVES

The aim of this study is to evaluate the rate of successful sedation and adverse events of intranasal procedural sedation using a combination of dexmedetomidine and ketamine for diagnostic examination in children.

METHODS

This was a retrospective study and data were collected after ethics approval. A total of 17 948 pediatric patients (7718 females, 10 230 males) in a tertiary hospital in China were evaluated. Patients received a combination of 2 μg kg^-1 of dexmedetomidine and 1 mg kg^-1 of ketamine intranasally for procedural sedation. The level of sedation and recovery was assessed by the Modified Observer Assessment of Alertness/Sedation scale and the Modified Aldrete Score.

RESULTS

The rate of intranasal sedation success was 93% (16691/17948), intranasal sedation rescue was 1.8% (322/17948), and intranasal sedation failure was 5.2% (935/17948). Sedation success was defined as successful completed the diagnostic examination and obtained adequate diagnostic-quality images and reports. Intranasal sedation success, rescue and failure were respectively defined as sedation success with intranasal a single dose, additional bolus dose and the need for intravenous (IV) medications/inhalation agents. Median sedation time was 62 min (interquartile range: 55-70 min), median time for onset of sedation was 15 min (interquartile range: 15-20 min), and median sedation recovery time was 45 min (interquartile range: 38-53 min). Incidence of adverse events was low (0.58%; 105/17948), with major and minor adverse event being reported in 0.02% (4/17948) and 0.56% (101/17948) patients, respectively. Postoperative nausea and vomiting was the most common (0.3%; 53/17948) minor adverse event.

CONCLUSION

Procedural sedation using a combination of intranasal dexmedetomidine and ketamine is associated with acceptable effectiveness and low rates of adverse events.

Population Pharmacokinetics of Intramuscular and Intravenous Ketamine in Children

Ketamine is an N-methyl D-aspartate receptor antagonist used off-label to facilitate dissociative anesthesia in children undergoing invasive procedures. Available for both intravenous and intramuscular administration, ketamine is commonly used when vascular access is limited. Pharmacokinetic (PK) data in children are sparse, and the bioavailability of intramuscular ketamine in children is unknown. We performed 2 prospective PK studies of ketamine in children receiving either intramuscular or intravenous ketamine and combined the data to develop a pediatric population PK model using nonlinear mixed-effects methods. We applied our model by performing dosing simulations targeting plasma concentrations previously associated with analgesia (>100 ng/mL) and anesthesia awakening (750 ng/mL). A total of 113 children (50 intramuscular and 63 intravenous ketamine) with a median age of 3.3 years (range 0.02 to 17.6 years), and median weight of 14 kg (2.4 to 176.1) contributed 275 plasma samples (149 after intramuscular, 126 after intravenous ketamine). A 2-compartment model with first-order absorption following intramuscular administration and first-order elimination described the data best. Allometrically scaled weight was included in the base model for central and peripheral volume of distribution (exponent 1) and for clearance and intercompartmental clearance (exponent 0.75). Model-estimated bioavailability of intramuscular ketamine was 41%. Dosing simulations suggest that doses of 2 mg/kg intravenously and 8 mg/kg or 6 mg/kg intramuscularly, depending on age, provide adequate sedation (plasma ketamine concentrations >750 ng/mL) for procedures lasting up to 20 minutes.

Comparison of Ketamine with Midazolam versus Ketamine with Fentanyl for Pediatric Extracorporeal Shock Wave Lithotripsy Procedure: A Randomized Controlled Study

Objectives

To compare the effects of ketamine-fentanyl (KF) and ketamine-midazolam (KM) combinations on hemodynamic parameters, recovery properties, pain, and side effects in pediatric patients undergoing extracorporeal shock wave lithotripsy (ESWL) procedure.

Methodology

In this double-blinded, randomized trial, 60 pediatric patients aged between 1 and 13 years with American Society of Anesthesiologists physical status Classes I and II, who scheduled for ESWL procedure, were included in the study. Patients were randomly divided into two groups: Group KM received 0.1 mg/kg of midazolam +1-1.5 mg/kg of ketamine and Group KF received 1 μg/kg of fentanyl +1-1.5 mg/kg of ketamine intravenously.

Results

There were similar demographic properties, recovery, and discharge times between groups. No statistically significant difference was found in peripheral oxygen saturation, mean and diastolic blood pressure, Ramsey sedation scores, modified Aldrete recovery scores, side effects, and recovery times (Group KM, 16.067 ± 1.2 min; Group KF, 19.46 ± 0.86 min) between groups (P > 0.05).

Conclusion

KF combination offers better hemodynamic properties, less side effects with lower visual analog scores, and face, legs, activity, cry, and consolability scores than KM in the pediatric ESWL procedure.

Dexmedetomidine-ketamine versus Dexmedetomidine-midazolam-fentanyl for monitored anesthesia care during chemoport insertion: a Prospective Randomized Study

Background

Dexmedetomidine as a sole agent showed limited use for painful procedures due to its insufficient sedative/analgesic effect, pronounced hemodynamic instability and prolonged recovery. The aim of this study was to compare the effects of dexmedetomidine-ketamine (DK) versus dexmedetomidine-midazolam-fentanyl (DMF) combination on the quality of sedation/analgesia and recovery profiles for monitored anesthesia care (MAC).

Methods

Fifty six patients undergoing chemoport insertion were randomly assigned to group DK or DMF. All patients received 1 μg.kg⁻¹ dexmedetomidine over 10 min followed by 0.2–1.0 μg.kg⁻¹h⁻¹ in order to maintain 3 or 4 of modified Observer's Assessment of Analgesia and Sedation score checked every 3 min. At the start of dexmedetomidine infusion, patients in group DK or DMF received 0.5 mg.kg⁻¹ ketamine or 0.05 mg.kg⁻¹ midazolam + 0.5 μg.kg⁻¹ fentanyl intravenously, respectively. When required, rescue sedatives (0.5 mg.kg-1 of ketamine or 0.05 mg.kg-1 of midazolam) and analgesics (0.5 mg.kg-1 of ketamine or 0.5 μg.kg-1 of fentanyl) were given to the patients in DK or DMF group, respectively. The primary outcome of this study was the recovery parameters (time to spontaneous eye opening and the length of the recovery room stay). The secondary outcomes were parameters indicating quality of sedation/analgesia, cardiorespiratory variables, and satisfaction scores.

Results

There were no significant differences in the onset time, time to spontaneous eye opening, recovery room stay, the incidences of inadequate analgesia, hypotension and bradycardia between the two groups. Despite lower infusion rate of dexmedetomidine, more patients in the DMF group had bispectral index (BIS) < 60 than in the DK group and vice versa for need of rescue sedatives. The satisfaction scores of patients, surgeon, and anesthesiologist in the DMF group were significantly better than the DK group.

Conclusions

The DK and DMF groups showed comparable recovery time, onset time, cardiorespiratory variables, and analgesia. However, the DMF group showed a better sedation quality and satisfaction scores despite the lower infusion rate of dexmedetomidine, and a higher incidence of BIS < 60 than the DK group.

Trial registration

Clinical Trial Registry of Korea KCT0000951, registered 12/12/2013

A study to compare the overall effectiveness between midazolam and dexmedetomidine during monitored anesthesia care: A randomized prospective study

Background:

Monitored anesthesia care (MAC) combines intravenous sedation along with local anesthetic infiltration or nerve block. Several drugs have been used for MAC, but all are associated with complications. Dexmedetomidine is a selective α2-adrenoceptor agonist with both sedative and analgesic properties and is devoid of respiratory depressant effects. Its short elimination half-life makes it an attractive agent for sedation during MAC.

Aim:

Comparative evaluation of dexmedetomidine and midazolam for MAC.

Methods:

In this prospective, randomized, double-blind study, 50 American Society of Anesthesiologist I and II patients undergoing a surgical or diagnostic procedure of <1 h requiring MAC were enrolled. Dexmedetomidine-ketamine (Group “KD”) patients (n = 25) received intravenous (I.V.) dexmedetomidine 1 mcg/kg over 10 min followed by 0.5 mg/kg of I.V. ketamine. Midazolam-ketamine patients (n = 25) received I.V. midazolam 0.05 mg/kg over 10 min followed by 0.5 mg/kg of I.V. ketamine to get a targeted level of sedation (≤4 using Observer's Assessment of Alertness/Sedation Scale score). Inadequate sedation (e.g., 15% increase in mean arterial blood pressure or heart rate, decrease in degree of calmness, increase in respiratory rate, physical movement) was treated by a ketamine bolus of 0.5 mg/kg as a rescue analgesia.

Statistical Analysis:

The statistical tests used in the study are unpaired Student's t-test for continuous variables and Chi-square test for categorical variables. Mann–Whitney test was used to assess the patient and surgeon satisfaction. Data were expressed as mean ± standard deviation. Value of P < 0.05 is considered significant and P < 0.0001 as highly significant.

Results:

Clinically desired sedation and analgesia was achieved earlier and better with dexmedetomidine. Patients and surgeons satisfaction were significantly higher with dexmedetomidine. The requirement of additional sedation and analgesia was less in dexmedetomidine (KD) group.

Conclusion:

During MAC dexmedetomidine provides better sedation and analgesia than midazolam.

Meta-analysis of dexmedetomidine on emergence agitation and recovery profiles in children after sevoflurane anesthesia: different administration and different dosage

The objective of this article is to evaluate the effect of dexmedetomidine on emergence agitation (EA) and recovery profiles in children after sevoflurane anesthesia and its pharmacological mechanisms. Standard bibliographic databases, including MEDLINE, EMBASE, PsycINFP, Springer and ISI Web of Knowledge, were artificially searched to identify all randomized controlled trials (RCTs) comparing the impact of dexmedetomidine with placebo, fentanyl and midazolam on EA and recovery profiles after sevoflurane anesthesia in post-anesthesia care unit (PACU). Two authors assessed the quality of each study independently in accordance with strict inclusion criteria and extracted data. RevMan 5.0 software was applied for performing statistic analysis. The outcomes analyzed included: 1) incidence of EA, 2) emergence time, 3) time to extubation, 4) incidence of post-operation nausea and vomiting, 5) number of patients requiring an analgesic, and 6) time to discharge from PACU. A total of 1364 patients (696 in the dexmedetomidine group and 668 in the placebo, fentanyl and midazolam group) from 20 prospective RCTs were included in the meta-analysis. Compared with placebo, dexmedetomidine decreased the incidence of EA (risk ratio [RR] 0.37; 95% CI 0.30 to 0.46), incidence of nausea and vomiting (RR 0.57; 95% CI 0.38 to 0.85) and number of patients requiring an analgesic (RR 0.43; 95% CI 0.31 to 0.59). However, dexmedetomidine had a significantly delayed effect on the emergence time (weighted mean differences [WMD] 1.16; 95% CI 0.72 to 1.60), time to extubation (WMD 0.61; 95% CI 0.27 to 0.95), and time to discharge from recovery room (WMD 2.67; 95% CI 0.95 to 4.39). Compared with fentanyl (RR 1.39; 95% CI 0.78 to 2.48) and midazolam (RR 1.12; 95% CI 0.54 to 2.35), dexmedetomidine has no significantly difference on the incidence of EA. However, the analgesia effect of dexmedetomidine on postoperation pain has no significantly statistical differences compared with fentanyl (RR 1.12; 95% CI 0.66 to 1.91), which implied that its analgesia effect might play an important role in decreasing the incident of EA. No evidence of publication bias was observed.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Laparoscopic appendectomy under spinal anesthesia with dexmedetomidine infusion

BACKGROUND

Laparoscopic appendectomy (LA) is rarely performed under regional anesthesia because of pneumoperitoneum-related problems. We expected that dexmedetomidine would compensate for the problems arising from spinal anesthesia alone. Thus, we performed a feasibility study of spinal anesthesia with intravenous dexmedetomidine infusion.

METHODS

Twenty-six patients undergoing LA received spinal anesthesia with intravenous dexmedetomidine infusion. During surgery, the patient's pain or discomfort was controlled by supplemental fentanyl or ketamine injection, and all adverse effects were evaluated.

RESULTS

No patient required conversion to general anesthesia, and all operations were completed laparoscopically without conversion to open surgery. Seventeen (65.4%) patients required supplemental injection of fentanyl or ketamine. Bradycardia occurred in seven (26.9%) patients.

CONCLUSIONS

Spinal anesthesia with dexmedetomidine infusion may be feasible for LA. However, additional analgesia, sedation, and careful attention to the potential development of bradycardia are needed for a successful anesthetic outcome.

Comparison of effects of dexmedetomidine-ketamine and dexmedetomidine-midazolam combinations in transurethral procedures

OBJECTIVE

To compare the effects of dexmedetomidine-ketamine and dexmedetomidine-midazolam combinations on the recovery time, hemodynamic and respiratory variables, and side effects in patients undergoing transurethral procedures.

METHODS

Sixty patients scheduled for elective outpatient transurethral procedure were randomized into 2 groups. In the group K, a ketamine-dexmedetomidine combination was administered, and in the group M, midazolam-dexmedetomidine was administered, to provide sedation/analgesia. Pain and sedation levels were assessed using visual analog score (VAS) and Ramsey Sedation Scale, respectively. The recovery time was assessed with the scale of Aldrete. Time was measured and recorded to the moment at which patient responses brought the Aldrete score to 10 points. Time to eye opening and length of stay in the recovery room were recorded.

RESULTS

Group M showed significantly lower mean arterial pressure (MAP) values at 5 and 10 minutes during the procedure when compared with group K (P = .02 and P = .01, respectively). Visual analogue scale scores were greater in group M than in group K at 5 and 10 minutes for the transurethral procedure (P = .039 and P = .028, respectively). Sedation scores were similar between groups during the procedure. Time to eye opening and length of recovery room stay were shorter (P < .001 and P < .001, respectively), and Aldrete scores were greater in group K than group M.

CONCLUSION

Both combinations provided satisfactory sedation levels, but the dexmedetomidine-ketamine combination provided better analgesia and hemodynamic stability, with less nausea and vomiting and shorter recovery time, than the dexmedetomidine-midazolam combination.

Dexmedetomidine and ketamine: an effective alternative for procedural sedation?

OBJECTIVES

Although generally effective for sedation during noninvasive procedures, dexmedetomidine as the sole agent has not been uniformly successful for invasive procedures. To overcome some of the pitfalls with dexmedetomidine as the sole agent, there are an increasing number of reports regarding its combination with ketamine. This article provides a descriptive account of the reports from the literature regarding the use of a combination of dexmedetomidine and ketamine for procedural sedation.

DATA SOURCE

A computerized bibliographic search of the literature regarding dexmedetomidine and ketamine for procedural sedation.

MEASUREMENTS AND MAIN RESULTS

The literature contains four reports with cohorts of more than ten patients with a total of 122 patients. Two of these studies were prospective randomized trials. Additionally, there are eight single case reports or small case series (six patients or less) with an additional 21 pediatric patients. When used together, dexmedetomidine may prevent the tachycardia, hypertension, salivation, and emergence phenomena from ketamine, whereas ketamine may prevent the bradycardia and hypotension, which has been reported with dexmedetomidine. An additional benefit is that the addition of ketamine to initiate the sedation process speeds the onset of sedation, thereby eliminating the slow onset time when dexmedetomidine is the sole agent. Although various regimens have been reported in the literature, the most effective regimen appears to be the use of a bolus dose of both agents, dexmedetomidine (1 µg/kg) and ketamine (1-2 mg/kg), to initiate sedation. This can then be followed by a dexmedetomidine infusion (1-2 µg/kg/hr) with supplemental bolus doses of ketamine (0.5-1 mg/kg) as needed.

CONCLUSIONS

The available literature except for one trial is favorable regarding the utility of a combination of ketamine and dexmedetomidine for procedural sedation. Future studies with direct comparisons to other regimens appear warranted for both invasive and noninvasive procedures.

Dexmedetomidine-ketamine sedation during bone marrow aspirate and biopsy in a patient with duchenne muscular dystrophy

Sedation during invasive procedures not only provides appropriate humanitarian care for patients, but also facilitates the completion of invasive procedures. Although generally safe and effective, adverse effects may occur especially in patients with co-morbid diseases. We present the successful use of a combination of dexmedetomidine and ketamine to provide sedation and analgesia in a 21-year-old patient with Duchenne muscular dystrophy (DMD) undergoing bone marrow aspiration and biopsy. Co-morbidities included both depressed myocardial function and impaired respiratory function. Dexmedetomidine was administered as a loading dose of 1 μg/kg over 5 min followed by an infusion of 1 μg/kg/h. Ketamine (20 mg) was administered along with the dexmedetomidine loading dose. An additional 10 mg of ketamine was administered to treat the pain experienced during the placement of the local anesthetic agent prior to the procedure. No clinically significant hemodynamic or respiratory changes were noted. The patient tolerated the procedure well and was discharged home. A review of previously published reports of dexmedetomidine and ketamine for procedural sedation are reviewed.