Continuous Intravenous Infusion Of Dexmedetomidine Research Articles

Retrospective comparison of the effects of remimazolam and dexmedetomidine on postoperative delirium in elderly patients undergoing orthopedic surgery of the lower extremities under spinal anesthesia.

Remimazolam is often used for perioperative sedation due to its rapid onset and offset. However, the possible association between remimazolam and postoperative delirium (POD) remains undetermined. The present study evaluated whether remimazolam increased the incidence of POD compared with dexmedetomidine in elderly patients undergoing orthopedic surgery of the lower extremities. This retrospective study included patients aged ≥ 65years who had undergone orthopedic surgery of the lower extremities under spinal anesthesia from January 2020 to November 2022 and were sedated with continuous intravenous infusion of dexmedetomidine or remimazolam. The incidence of POD was assessed through a validated comprehensive review process of each patient's medical records. The effect of remimazolam on the occurrence of POD compared with dexmedetomidine was evaluated by propensity score weighted multivariable logistic models. A total of 447 patients were included in the final analysis. The crude incidence of POD within 3days after surgery was 7.5% (17/226) in the dexmedetomidine group and 11.8% (26/221) in the remimazolam group, increasing to 9.7% (22/226) and 15.8% (35/221), respectively (p = 0.073), within 5days. The multivariable models showed that, compared with dexmedetomidine, intraoperative sedation with remimazolam significantly increased the occurrence of POD within 3days (odds ratio [OR] 2.21, 95% confidence interval [CI] 1.31 to 3.82, p = 0.003) and 5days (OR 2.10, 95% CI 1.32 to 3.40, p = 0.002). Compared with dexmedetomidine, remimazolam infusion may be associated with a higher risk of POD in elderly patients undergoing orthopedic surgery of the lower extremities under spinal anesthesia.

Determination of the ED90 of Dexmedetomidine Infusion to Prevent Emergence Agitation in Children Undergoing Dental Rehabilitation With Sevoflurane Anesthesia: A Biased-Coin Up-and-Down Sequential Allocation Trial.

Emergence agitation (EA) is an adverse complication during early recovery from sevoflurane anesthesia. Continuous intravenous infusion of dexmedetomidine (DEX) is commonly used for EA prevention. However, a wide dose range is used for preventing EA, and the optimal dose remains unknown. This study was aimed at determining the optimal dose (the 90% effective dose [ED90]) of DEX for continuous intraoperative infusion for EA prevention in children. We enrolled children aged 3 to 7 years who underwent dental treatment under sevoflurane anesthesia. DEX was continuously infused from the time of the establishment of the intravenous access until 5 minutes before the end of surgery. The initial DEX dose was 0.5 µg/kg/h, and subsequent dose adjustments were determined based on the response of the previous patient by using an up-down sequential allocation with a biased-coin design. The primary outcome was the ED90 for continuous DEX infusion based on the success or failure of the EA-preventing dose. Forty-five patients were enrolled in the study. The DEX dose ranged from 0.50 to 0.90 µg/kg/h. The estimated ED90 (95% confidence interval [CI]) for preventing EA was 0.74 µg/kg/h (0.67-1.05 µg/kg/h). The duration of surgery (mean ± standard deviation [SD]) was 113 ± 30 minutes. The times (mean ± SD) for extubation, time to emergence, and recovery time were 5 ± 2 minutes, 27 ± 9 minutes, and 39 ± 7 minutes, respectively. The ED90 for continuous intraoperative DEX infusion for EA prevention in pediatric patients receiving dental treatment under sevoflurane anesthesia was 0.74 µg/kg/h (95% CI, 0.67-1.05 µg/kg/h).

The role of dexmedetomidine administered via intravenous infusion as adjunctive therapy to mitigate postoperative delirium and postoperative cognitive dysfunction in elderly patients undergoing regional anesthesia: a meta-analysis of randomized controlled trials

Study objectiveThis meta-analysis aimed to assess whether continuous intravenous administration of DEX during surgery can be part of the measures to prevent the onset of postoperative delirium and postoperative cognitive dysfunction in elderly individuals following regional anesthesia.MethodsWe searched the databases of PubMed, Embase, the Cochrane Library and China National Knowledge Infrastructure (by June 1, 2023) for all available randomized controlled trials assessing whether intravenous application of dexmedetomidine can help with postoperative delirium and postoperative cognitive dysfunction in the elderly with regional anesthesia. Subsequently, we carried out statistical analysis and graphing using Review Manager software (RevMan version 5.4.1) and STATA software (Version 12.0).Main resultsWithin the scope of this meta-analysis, a total of 18 randomized controlled trials were included. Among them, 10 trials aimed to assess the incidence of postoperative delirium as the primary outcome, while the primary focus of the other 8 trials was on the incidence of postoperative cognitive dysfunction. The collective evidence from these 10 studies consistently supports a positive relationship between the intravenous administration of dexmedetomidine and a decreased risk of postoperative delirium (RR: 0.48; 95%CI: 0.37 to 0.63, p < 0.00001, I2 = 0%). The 8 literature articles and experiments evaluating postoperative cognitive dysfunction showed that continuous intravenous infusion of dexmedetomidine during the entire surgical procedure exhibited a positive preventive effect on cognitive dysfunction among the elderly population with no obvious heterogeneity (RR: 0.35; 95%CI: 0.25 to 0.49,p < 0.00001, I2 = 0%).ConclusionAdministering dexmedetomidine intravenously during surgery can potentially play a significant role in preventing postoperative delirium and postoperative cognitive dysfunction in patients older than 60 years with regional anesthesia according to this meta-analysis.

Role of dexmedetomidine in modifying immune paralysis in patients with septic shock: randomized controlled trial

BackgroundImmune paralysis can be defined as a hypoinflammatory state associated with the incapacity of the immune system to release proinflammatory mediators despite the clearance of pathogens by antimicrobials. Persistent immune paralysis leads to failure to eradicate primary infections with a substantial increase in the risk of multiorgan dysfunction and mortality. The state of immune paralysis is caused mainly by the diminished ability of monocytes to release proinflammatory cytokines in response to endotoxin. This phenomenon is known as endotoxin tolerance. This study aimed to assess the role of dexmedetomidine in modifying immune paralysis in septic shock patients.MethodsTwenty-four patients with septic shock were randomized into two groups of 12 patients. A continuous intravenous infusion of dexmedetomidine started at 0.15 µg kg−1 hr−1 and adjusted by 0.15 µg kg−1 h−1 to a maximum of 0.75 µg kg−1 h−1 (10 ml h−1), while midazolam was started at 1 mg h−1 (2 mL hr−1) and adjusted by 1 mg h−1 to a maximum of 5 mg h−1 (10 mL h−1). All infusions were adjusted by increments of 2 mL/hr−1 to maintain blinding. Serum levels of CD42a+/CD14+, HLADR+/CD14+, CRP, IL-6, IL-10 and TNF-α were measured at baseline (T1), 12 h (T2), and 24 h (T3).ResultsTreatment with dexmedetomidine yielded no significant difference in CD42a+/CD14+, HLADR+/CD14, CD24b-MFI, HLADR-MFI, IL6 and TREM1 at all time points when compared with midazolam treatment. There was no significant difference in TLR levels between the two groups. Cardiac output in the dexmedetomidine group showed a significant decrease at 6, 12 and 24 h (P = 0.033, 0.021, and 0.005, respectively) compared with that in the midazolam group.ConclusionOur results indicated that dexmedetomidine did not affect CD42a+/CD14+ and HLA-DR+/CD14+ expression in septic patients. Furthermore, cytokine production and inflammatory biomarkers did not change with dexmedetomidine infusion.Trial registration Clinical trial.gov registry (NCT03989609) on June 14, 2019, https://register.clinicaltrials.gov.

The effect of dexmedetomidine on wake-up test quality when muscle relaxants are not used: A randomized control trial.

Stagnara wake-up test is a simple reproducible neuromonitoring method during spinal surgery which replaces the evoked potential monitoring in the absence of neuromonitoring facilities. Dexmedetomidine (DEX) effect on the intraoperative wake-up test is still unclear. The present study was conducted to evaluate the effectiveness of DEX on the quality of wake-up test during spinal correction surgery. A randomized controlled study was carried out over 62 patients randomized into two equal groups planned for elective minimally invasive corrective spine surgery. Instead of atracurium administration in the control group, patients in the experimental group were administered titrated continuous intravenous infusion of DEX at a dose of 0.2-0.7 μg/kg/hour. Lidocaine 2% spray around the vocal cords was done in both the groups to facilitate toleration of the endotracheal tube. The DEX group showed statistically significant longer duration and better quality of the wake-up test. Statistically significant better haemodynamic state, a lower amount of intraoperative sedatives and higher amount of intraoperative analgesics were also evident in the DEX group. The postoperative Ramsay sedation scale was significantly lower in the DEX group just after extubation. The DEX use has shown an improving effect on the wake-up test quality, with slightly prolonged wake-up time. The present work supports the use of DEX as an adjuvant drug alleviating the need for the neuromuscular blockade, inducing a better haemodynamic profile, exhibiting better sedation and improving the awakening condition.

Study on the protective mechanism of dexmedetomidine on the liver of perioperative diabetic patients: A randomized controlled trial.

Background:Although several studies have reported that dexmedetomidine is a highly selective α2-adrenergic receptor agonist that protects liver function in perioperative patients by inhibiting oxidative stress (OS) and inflammatory response, patients with type 2 diabetes mellitus (T2DM) have not been included in the previous studies. The purpose of this study was to investigate the effects of perioperative low-dose dexmedetomidine on perioperative liver function in T2DM patients.Methods:This was a single-center, placebo-controlled randomized trial. Fifty-four T2DM patients scheduled for debridement of lower extremity ulcers were included in this study and randomly divided into 2 groups (n = 27 per group): the dexmedetomidine group (DEX group) and the control group (CON group). Continuous intravenous infusion of dexmedetomidine (DEX group) or normal saline (CON group) was administered from the completion of monitoring to the end of surgery. All participants received femoral and sciatic nerve block with 0.33% ropivacaine. The main result was the activity of liver enzymes (AST, ALT) reflecting liver function. The secondary results included variables reflecting blood glucose (Glu), blood lipids (TG, HDL, LDL, total cholesterol), biomarkers of OS (MDA, SOD), and systemic inflammatory response (TNF-α, IL-6).Results:Compared with CON group, DEX group exhibited a reduction in hemodynamic parameters, Glu, systemic inflammatory response, and liver injury indicators. OS response MDA activity was lower in DEX group than in CON group, while SOD was higher than that in CON group. The variables reflecting lipid metabolism function showed no differences between the groups.Conclusion subsections:Dexmedetomidine administered perioperatively can reduce Glu levels and protect the liver by attenuating OS injury and inflammatory response in T2DM patients without any potential risk.

Effects of Dexmedetomidine on Postoperative Pain and Recovery Time in Obese Patients.

Objective The objective of this study is to investigate the effect of dexmedetomidine on postoperative pain and recovery time in obese patients. Methods A total of 100 obese patients with body mass index (BMI) ≥ 30 kg/m2 who underwent laparoscopic sleeve gastrectomy under general anesthesia in our hospital from January 2019 to December 2021 were included and assigned into DEX group (dexmedetomidine group) and NS group (normal saline group). The bariatric surgery patients who were given normal saline pump were the NS group (n = 50), and the bariatric surgery patients who were given the dexmedetomidine pump were the DEX group (n = 50). The patients in the DEX group were given continuous intravenous infusion of dexmedetomidine before, during, and after induction of anesthesia at a dose of 0.4 μg. kg-1. h-1, 0.4 μg·kg-1. h-1, 0.2 μg·kg-1. h-1, respectively. The NS group was infused with the same volume of normal saline for the same time. The two groups of patients were treated with the same anesthesia induction and maintenance program. By comparing the operation, anesthesia, postoperative extubation, and recovery time of the two groups of patients, the effect of dexmedetomidine on the postoperative recovery time of obese patients was analyzed. Visual analogue scale (VAS) and adverse reactions were compared to analyze the effect of dexmedetomidine on postoperative pain in obese patients. Results The operation, anesthesia, postoperative extubation, and recovery time of the DEX group were significantly lower than those of the NS group, whereas the VAS and adverse reactions were significantly lower than those in the NS group (P < 0.05). Conclusion An appropriate dose of dexmedetomidine in bariatric surgery for morbidly obese patients can effectively shorten the recovery time and extubation time of patients, reduce postoperative pain and the incidence of adverse reactions, and is worthy of clinical application. Dexmedetomidine 2 μg/kg has promising anesthesia benefits in bariatric surgery of obese patients, can provide favorable analgesia and quality of recovery, help reduce the degree of stress response of patients, and does not increase the risk of adverse events. However, this study has certain limitations, so physicians should tailor the dosage according to the patient's physical condition in clinical practice.

Intraoperative use of low-dose dexmedetomidine for the prevention of emergence agitation following general anaesthesia in elderly patients: a randomized controlled trial.

To clarify the effect of an intraoperative low-dose dexmedetomidine infusion on emergence agitation following general anaesthesia in elderly patients. Eighty elderly patients (> 64-years-old) following elective general anaesthesia for radical cancer surgeries were randomly allocated into two groups (n = 40 each): the dexmedetomidine group (Group D) and the normal saline group (Group C). Anaesthesia was maintained with continuous intravenous infusion of dexmedetomidine at -0.2µgkg-1h-1 in Group D, and an equal volume of normal saline (0.5mlkg-1h-1) was given in Group C. All patients were observed for 30min in the post-anaesthesia care unit (PACU), AFPS and NRS were recorded every 2min, and the total doses of nalbuphine and fentanyl were calculated in the PACU. MAP and HR were recorded at the time of 10min (T1), 20min (T2), 30min (T3) after dexmedetomidine or saline pumping, and before extubation (T4), immediately after extubation (T5), and 5min after extubation (T6). We also documented some durations, including anaesthesia duration (D1), surgery duration (D2), duration from the end of surgery to extubation (D3), and emergence agitation duration (D4). The MAP in Group C was significantly higher than that in Group D (P < 0.05), and there were no significant changes between the two groups in HR and MAP within each time point and D1, D2, D3, and D4. The incidence of agitation, NRS score and total dose of nalbuphine and fentanyl were all lower in Group D than in Group C (P < 0.05). An intraoperative low-dose dexmedetomidine continuous infusion can reduce emergence agitation following general anaesthesia in elderly patients (> 64-years-old), remain stable in terms of haemodynamics, and not lead to delays in anaesthesia recovery time and extubation time.

Comparison of the Analgesic Effects of Intravenous Infusion of Dexmedetomidine Versus Bilateral Superficial Cervical Plexus Block After Thyroidectomy: A Randomized Controlled Trial.

Dexmedetomidine (DEX) is widely used in clinical practice because of its safety and effectiveness. Superficial cervical plexus block (SCPB) can reduce pain in thyroid surgery. The objective of this study was to investigated whether intravenous DEX has an equivalent analgesic effect and patients' satisfaction to SCPB for thyroid surgery. Ninety patients who had been scheduled for thyroidectomy under general anesthesia with endotracheal intubation were randomly divided into 3 groups. Group D: DEX was administered intravenously at an initial dose of 1 µg/kg over 10 minutes; then induction and endotracheal intubation performed, and then a continuous intravenous infusion of DEX was administered at a rate of 0.4 μg/kg/h until 30 minutes before the end of surgery. Group B: ultrasound-guided bilateral SCPB was performed, with 10 mL of 0.375% ropivacaine injected on each side. Group C: intravenous saline was administered at the same rate and dose as in group D. Patients' perioperative status, visual analog scale scores, complications and patients' satisfaction were recorded. The pain at rest at 1 hour after extubation and the movement-evoked pain within 24 hours after extubation were significantly lower in groups D and B than in group C. Patients' satisfaction was significantly higher in groups D and B than in group C. There was no difference in pain at rest, movement-evoked pain and patients' satisfaction between group D and B. Perioperative intravenous infusion of DEX can effectively reduce wound pain after thyroidectomy, and the analgesic effect is equivalent to that of bilateral SCPB.

Clinical research of early goal directed sedation applying in acute brain injury

To investigate the value and feasibility of early goal directed sedation (EGDS) in patients with acute brain injury. A total of 110 patients with acute brain injury who were admitted to intensive care unit (ICU) of the Third Medical Center of the Chinese People's Liberation Army General Hospital from January 2015 to March 2019 were included and randomly divided into EGDS group and standard sedation group (STD) using the random number table. Patients in the EGDS group were sedated by continuous intravenous infusion of dexmedetomidine (initial dose of 0.2 μg×kg-1×min-1) for 72 consecutive hours. Patients in the STD group received intravenous bolus of propofol as appropriate clinically. Richmond agitation-sedation score (RASS) and electroencephalogram bispectral index (BIS) were used to continuously monitor the level of sedation. All patients were given sufentanil for analgesia. Routine treatments such as dehydration and reduction of intracranial pressure with mannitol, hemostasis or antiplatelet therapy were given according to the patients' condition. Vital signs, acute physiology and chronic health evaluation II (APACHE II) score, Glasgow coma scale (GCS) score, BIS value, artery blood gas analysis, duration of mechanical ventilation, analgesic dosage and adverse events were recorded in two groups before and 24, 48, and 72 hours after sedation. (1) Among the 110 patients, patients who received the second surgery due to cerebral hemorrhage, had worsening of cerebral hernia, withdrew during the course of the study, or whose family members abandoned treatment were excluded from the study. Finally, 105 patients were enrolled in the study, including 56 patients in the EGDS group and 49 in the STD group. There was no significant difference in gender, age, types of brain injury, baseline APACHE II or GCS score or rate of mechanical ventilation between the two groups. (2) Compared with before sedation, heart rate (HR) significantly decreased till 72 hours after sedation in both groups, and the decrease in the EGDS groups was more obvious as compared with the STD group (bpm: 70.49±7.53 vs. 79.83±9.48, P < 0.05). Besides HR, significant improvement was found in the APACHE II and GCS scores in the STD group at 72 hours of sedation as compared with before sedation, and no significant difference was found in other indicators. Compared with before sedation, arterial partial pressure of carbon dioxide (PaCO2) was significantly increased from the 24th hour of sedation, mean artery pressure (MAP) was decreased significantly and GCS score, BIS value were increased significantly from the 48th hour of sedation, till 72 hours, which were all improved significantly as compared with the STD group [72-hour PaCO2 (mmHg, 1 mmHg = 0.133 kPa): 40.30±5.98 vs. 31.57±8.20, 72-hour MAP (mmHg): 85.01±8.26 vs. 89.54±9.41, 72-hour GCS score: 8.62±3.34 vs. 7.89±2.74, 72-hour BIS: 60.87±24.79 vs. 56.68±33.43, all P < 0.05]. APACHE II score was significantly lower only at the 72nd hour of sedation as compared with before sedation in the EGDS group, and no significant difference was found as compared with the STD group (17.10±7.05 vs. 18.90±3.32, P > 0.05). Oxygenation index (PaO2/FiO2) was significantly increased only at the 24th hour of sedation in the EGDS group as compared with the STD group (mmHg: 261.05±118.45 vs. 226.45±96.54, P < 0.05). (3) The duration of mechanical ventilation was significantly shorter in the EGDS group than that in the STD group (hours: 20.56±9.03 vs. 27.75±11.23, P < 0.05), and the total administered dose of sufentanil was significantly lower in the EGDS group than that in the STD group (μg: 79.16±26.76 vs. 102.46±35.48, P < 0.05). (4) Compared with the STD group, the incidence of bradycardia in the EGDS group was increased significantly [10.71% (6/56) vs. 6.12% (3/49), P < 0.05], while the incidence of tachycardia was decreased significantly [14.29% (8/56) vs. 38.78% (19/49), P < 0.05], but no significant difference was found in the incidence of hypotension [5.36% (3/56) vs. 4.08% (2/49), P > 0.05]. The incidence of unexpected extubation in the STD group was 4.08% (2/49), which did not occurre in the EGDS group. EGDS can improve the GCS score and BIS value of patients with acute brain injury, suggesting that the EGDS is safe and feasible, which can help improve neurological function in patients with acute brain injury.

A Comparative Study on Efficacy and Safety of Propofol versus Dexmedetomidine in Sleep Apnea Patients undergoing Drug-Induced Sleep Endoscopy: A CONSORT-Prospective, Randomized, Controlled Clinical Trial.

The aim of this study is to compare the efficacy and safety of propofol with dexmedetomidine in patients with obstructive sleep apnea hypopnea syndrome (SAHS) undergoing drug-induced sleep endoscopy (DISE). The 88 patients diagnosed with SAHS in the Affiliated Hospital of Xuzhou Medical University were randomly allocated into 2 groups (n = 44). Patients in the group dexmedetomidine (group D) received continuous intravenous infusion of dexmedetomidine 1 μg/kg over 15 minutes before the endoscopy, and propofol 2 mg/kg was intravenously administrated in the group propofol (group P). Cardiopulmonary parameters of patients were recorded. The time to fall asleep, duration of endoscopic examination, the wakeup time of patients, the number of mask ventilations for patients, the satisfaction of patients and endoscopic performers, and false positive cases of SAHS of patients were compared between the two groups. Compared with group D, mean arterial pressure (MAP) and blood oxygen saturation (SPO2) of patients in the P group were lower at the time point of T1 (P < 0.05), the duration of endoscopic examination and wakeup time of patients were obviously prolonged, the incidence of mask ventilation for patients and false positive cases of SAHS of patients was observably higher, and the satisfaction of endoscopic performers was markedly lower, but the time to fall asleep was significantly shortened (P < 0.05). Dexmedetomidine served as a novel sleep induced drug and can provide satisfactory conditions and be safely and effectively applied for endoscopy in patients with SAHS, without adverse hemodynamic effects.

Influence of dexmedetomidine and lidocaine on perioperative opioid consumption in laparoscopic intestine resection: a randomized controlled clinical trial

ObjectiveThe consumption of opioid analgesics could be reduced by the use of analgesics with different mechanisms of action. We investigated whether additional treatment with dexmedetomidine or lidocaine could reduce opioid consumption.MethodsWe randomized 59 study participants into three groups and examined: (i) fentanyl consumption, (ii) consumption of piritramide, and (iii) cognitive function and neuropathic pain. The control group received continuous propofol infusion and fentanyl boluses. Continuous intravenous infusion of dexmedetomidine (0.5 µg/kg/h) was administered to the dexmedetomidine group and lidocaine (1.5 mg/kg/h) was administered to the lidocaine group.ResultsNo reduction in fentanyl consumption was observed among the groups. However, we noted a significantly lower consumption of piritramide on the first and second postoperative day in the lidocaine group. Total consumption of piritramide was significantly lower in the lidocaine group compared with the control group.ConclusionsLidocaine and dexmedetomidine reduced intraoperative propofol consumption, while lidocaine reduced postoperative piritramide consumption.Clinical trial registration: NCT02616523

Effects of Continuous Intravenous Infusion of Dexmedetomidine on the Duration of Spinal Anesthesia: A Prospective, Double-Blind, Randomized, Controlled Trial

Background: Spinal anesthesia with sedation is a common anesthetic technique in infraumbilical surgeries. Dexmedetomidine has been widely used as a sedative during spinal anesthesia, and is recognized as an adjuvant that prolongs the duration of spinal anesthesia. We compared the effects of a continuous intravenous infusion of dexmedetomidine to provide intraoperative sedation on the duration of sensory and motor blockade induced by spinal anesthesia, with those of midazolam. Methods: A double-blind randomized controlled trial was performed on 40 patients, aged between 20 and 75 years, who requested intraoperative sedation, and were classified as American Society of Anesthesiologists (ASA) physical status I-II, and underwent elective surgeries under spinal anesthesia. After spinal anesthesia with 13 mg (2.6 ml) of 0.5% hyperbaric bupivacaine, patients were randomized to receive intravenous dexmedetomidine 3 μg/kg/h for 10 mins followed by an infusion of 0.5 μg/kg/h (Group D), or intravenous midazolam 0.15 mg/kg/h for 10 mins followed by an infusion of 0.025 mg/kg/h (Group M). Sedation was titrated to Observer’s Assessment of Alertness/Sedation (OAA/S) score of 3. Sensory and motor blockade was evaluated using the pinprick test and modified Bromage scale, respectively. Results: The time taken to achieve OAA/S score 3 was similar in the two groups. The maximal level of sensory blockade was 5.3 ± 1.3 min in group D and 4.1 ± 1.5 in group M (P = 0.03). No significant differences were observed in the time taken to achieve the maximal level or the two-segment regression time of sensory blockade between the two groups. The time to sensory regression to the L2 level was significantly longer in group D than in group M (234.6 ± 78.1 mins versus 172.4 ± 41.5 mins, respectively, P = 0.008). The time to motor regression to modified Bromage score 1 was significantly longer in group D than in group M (232.2 ± 79.3 versus 176.5 ± 48.8, respectively, P = 0.02). Conclusion: Continuous intravenous dexmedetomidine to provide sedation during spinal anesthesia significantly prolongs the duration of sensory and motor blockade induced by spinal anesthesia over that with midazolam.

Dexmedetomidine-treated hyperventilation syndrome triggered by the distress related with a urinary catheter after general anesthesia: a case report

BackgroundHyperventilation syndrome (HVS) sometimes occurs in patients under stressful conditions and may provoke severe complications such as myocardial infarction and death. The authors report a case of HVS following general anesthesia, where a continuous intravenous infusion of dexmedetomidine was effective for HVS.Case presentationA 23-year-old male patient with recurrent tongue cancer was scheduled to undergo partial glossectomy and neck dissection. Emergence from general anesthesia was prompt. Twenty-two minutes after extubation, the patient complained of unbearable distress caused by the urinary catheter. He began to cry, with an increased respiratory rate of over 40 breaths per minute. Intravenous infusion of flurbiprofen, droperidol, and morphine was not effective. Electrocardiography and laryngofiberscopy indicated the absence of acute coronary syndrome and airway obstruction, respectively. An arterial blood gas determination showed pH 7.63, PaCO2 18.2 mmHg, PaO2 143 mmHg on O2 mask 4 L/min, Ca2+ 4.29 mmol/L, and lactate 3.4 mmol/L. The patient was diagnosed with HVS. Dexmedetomidine infusion 2.0 μg/kg/h for 10 min followed by 0.7 μg/kg/h reduced respiratory rate, suppressed arousal, and disappeared the complaint of bladder distension. One hour after extubation, an arterial blood gas determination showed pH 7.33, PaCO2 51.3 mmHg, PaO2 196 mmHg on O2 mask 4 L/min, Ca2+ 4.70 mmol/L, and lactate 1.5 mmol/L. After admission to the intensive care unit, dexmedetomidine infusion was maintained at the rate of 0.2 to 0.7 μg/kg/h until the following morning, and he did not complain of distress caused by the urinary catheter.ConclusionsHVS can occur after emergence from general anesthesia, and dexmedetomidine infusion was effective for HVS.

A prospective randomized study comparing recovery following anesthesia with a combination of intravenous dexmedetomidine and desflurane or sevoflurane in spinal surgeries.

Background and Aims:Desflurane and sevoflurane are inhalational anesthetics which provide stable intraoperative hemodynamics and rapid emergence from anesthesia. Dexmedetomidine is an α2-agonist with sedative and hypnotic effects. We compared recovery following anesthesia with a combination of a continuous intravenous infusion of dexmedetomidine and desflurane or sevoflurane in cases of spine surgeries because no such data are available from India.Material and Methods:It was a single-blind, prospective, randomized study. After institutional ethics committee approval, patients were randomly allocated to one of the two groups of fifty patients each. Group D received desflurane and Group S received sevoflurane, along with dexmedetomidine 0.5 μg/kg/h IV infusion for maintenance of anesthesia.Results and Conclusions:Extubation time (ET) in Group D was shorter by 4.2 min than in Group S (10.1 ± 2.2 and 14.2 ± 1.3; P = 0.004). Postoperative recovery, postoperative analgesic, and antiemetic requirement between the groups were comparable The mean dial setting required to maintain the minimum alveolar concentration of 1 intraoperatively was 3.1 for desflurane and 0.7 for sevoflurane.

A Comparison of Dexmedetomidine and Clonidine in Attenuating the Hemodynamic Responses at Various Surgical Stages in Patients Undergoing Elective Transnasal Transsphenoidal Resection of Pituitary Tumors.

Background:Transsphenoidal approach to pituitary tumors is a commonly performed procedure with the advantage of a rapid midline access to the sella with minimal complications. It may be associated with wide fluctuations in hemodynamic parameters due to intense noxious stimulus at various stages of the surgery. As duration of the surgery is short and the patients have nasal packs, it is prudent to use an anesthestic technique with an early predictable recovery.Materials and Methods:A total of 60 patients of either sex between 18 and 65 years of age, belonging to the American Society of Anesthesiologists I and II who were undergoing elective transnasal transsphenoidal pituitary surgery were chosen for this study. Patients were randomly allocated into two groups, Group C (clonidine) and Group D (dexmedetomidine), with each group consisting of 30 patients. Patients in Group C received 200 μg tablet of clonidine and those in Group D received a pantoprazole tablet as placebo at the same time. Patients in the Group D received an intravenous infusion of dexmedetomidine diluted in 50 ml saline (200 μg in 50 ml saline) 10 min before induction and patients in Group C received 0.9% normal saline (50 ml) as placebo. The hemodynamic variables (heart rate, mean arterial pressure) were noted at various stages of the surgery. Statistical analysis of the data was performed.Results:A total of 60 patients were recruited. The mean age, sex, weight and duration of surgery among the two groups were comparable (P > 0.05). Both dexmedetomidine and clonidine failed to blunt the increase in hemodynamic responses (heart rate and blood pressure) during intubation, nasal packing, speculum insertion and extubation. However when the hemodynamic response was compared between the patients receiving dexmedetomidine and clonidine it was seen that patients who received dexmedetomidine had a lesser increase in heart rate and blood pressure (P < 0.05) when compared to clonidine.Conclusions:A continuous intravenous infusion of dexmedetomidine as compared to oral clonidine improved hemodynamic stability in patients undergoing transnasal transsphenoidal resection of pituitary tumors.

A comparative study between propofol and dexmedetomidine as sedative agents during performing transcatheter aortic valve implantation

ObjectiveThe type of sedative drugs could play a major role in providing hemodynamic stability which is crucial during transcatheter aortic valve implantation (TAVI) procedure. The aim of this study is to compare propofol with dexmedetomidine for conscious sedation during TAVI. DesignA prospective randomized pilot study. PatientsFifty patients with a mean age of 74years, American Society of Anesthesiologists 3-4, complaining from severe aortic stenosis were enrolled in this study to undergo TAVI. InterventionsThe propofol group (group P; n=25) received a bolus dose of 0.5mg/kg propofol followed by a continuous intravenous infusion of propofol at a rate of 30 to 50μg kg−1 min−1, and the dexmedetomidine group (group D; n=25) received dexmedetomidine at a loading dose of 1μg/kg and then a continuous intravenous infusion of dexmedetomidine at a rate of 0.5μg kg−1 h−1. MeasurementsHeart rate, mean arterial blood pressure, number of phenylephrine boluses, oxygen saturation, sedation, and satisfaction scores were measured just after the start of infusion of the sedation drugs and at the end of the procedure. Postoperative complications were also recorded. ResultsThere was a statistically significant reduction in the heart rate in group D in comparison to group P where it was 67.28±6.9beats/min in the first group in comparison to 78±6.9beats/min in the last one (P<.001). The mean arterial blood pressure was statistically significant lower in group D in comparison to group P (58.12±5.4mm Hg in group D vs 68.24±11.4mm Hg in group P; P<.001). Also, the number of phenylephrine boluses was higher in group D than in group P (36.5±7.17 in group D vs 20.6±2.07 in group p; P<.001). No difference between the 2 groups regarding oxygen saturation, sedation, pain, satisfaction scores, and postoperative complications. ConclusionDuring TAVI, dexmedetomidine may be associated with significant hypotension and bradycardia rather than propofol.

Intravenous Dexmedetomidine Promotes Spinal Bupivacaine Anesthesia and Postoperative Analgesia in Lower Limb Surgery: A Double-Blind, Randomized Clinical CONSORT Study.

Dexmedetomidine (DEX) has been reported to have synergistic action with local anesthetics. This prospective, randomized, double-blind clinical study was designed to observe the efficacy of intravenous DEX without loading dose on spinal blockade duration, postoperative sedation, patient-controlled analgesia and its morphine-sparing effect in lower limb surgeries.Seventy-five patients, scheduled for lower limb surgery under spinal anesthesia, were randomly allocated into 2 groups: group BS (received 15 mg of 0.5% of bupivacaine for subarachnoid anesthesia and continuous intravenous infusion of saline in Ringer solution) and BD group (received 15 mg of 0.5% of bupivacaine for subarachnoid anesthesia and continuous intravenous infusion of DEX in Ringer solution at a rate of 0.25 μg/kg/h). Intravenous infusion started 15 minutes before spinal anesthesia.The onset time of sensory and motor blockade was shorten, the duration of sensory and motor blockade was significantly prolonged in BD patients when compared to BS patients. The Ramsay sedation score measured immediately after surgery was greater in BD group than BS group. BD patients also shown increased time to the first request of postoperative morphine and decreased total morphine consumption as compared with BS patients.Collectively, intravenous administration of DEX without loading dose promoted the efficacy of spinal bupivacaine anesthesia and postoperative analgesia in patients undergoing lower limb surgery.

Dexmedetomidine decreases the emergence agitation in infant patients undergoing cleft palate repair surgery after general anesthesia.

BackgroundTo determine whether continuous intravenous infusion of dexmedetomidine (DEX) can affect the incidence of Emergence Agitation (EA) after general anesthesia in infant undergoing cleft palate repair surgery.MethodsForty infants underwent cleft palate repair surgery under general anesthesia were randomly divided into the DEX (D) group and Placebo (P) groups. Patients in group D received continuous intravenous infusion of DEX 0.8 μg · kg-1 · min-1 after the induction. Patients in group P were administered with continuous intravenous infusion of the equivalent volume of normal saline. Both groups were induced with fentanyl 0.005 mg/Kg, propofol 2 mg/Kg and cisatracurium 0.2 mg/Kg. Anaesthesia was maintained with continuous intravenous infusion of propofol (2 mg/Kg · h), remifentanil (0.1 μg/Kg · h), and inhalation of 1 to 3 % sevoflurane.ResultThe heart rate (HR) in group P was significant higher than that in group D at the time of operation (P < 0.05), postoperative 15 min, 30 min and the time of extubation (P < 0.01). The mean arterial pressure (MAP) in group P was higher comparing with MAP in group D at the time of extubation (P < 0.05). The spontaneous eye opening times and spontaneous arm or leg motion times were longer in group D (P < 0.05). The mean agitation scores of patients in group D were significantly lower than that in group P (P < 0.01). However, the incidence of EA in group P and group D was 90 % and 15 % (P <0.05).ConclusionThe continuous intravenous infusion of DEX after induction could significantly reduce the occurrence of EA.Trial registrationThe Chinese Clinical Trial Register ChiCTR-TRC-13003865

Midazolam with meperidine and dexmedetomidine vs. midazolam with meperidine for sedation during ERCP: prospective, randomized, double-blinded trial

The combination of midazolam and opioid has been widely used as a standard sedative regimen for endoscopic retrograde cholangiopancreatography (ERCP). Following recent evidence that dexmedetomidine may exert a synergistic effect in combination with midazolam, this study compared the sedative effect and adverse events of midazolam - meperidine - dexmedetomidine (MMD) and midazolam - meperidine during ERCP. A total of 110 patients who were scheduled for ERCP were prospectively enrolled and randomly assigned, in a double-blind manner, to the MMD (n = 53) or midazolam - meperidine (n = 57) groups. Each patient received an intravenous (IV) bolus dose of midazolam and meperidine (0.06 mg/kg and 50 mg, 30 % reduction and 25 mg for patients aged ≥ 65 years, respectively). To this dose, a continuous IV infusion of dexmedetomidine (1 μg/kg/h; MMD group) or the same volume of normal saline (midazolam - meperidine group) was added. The sedation level (Ramsay Sedation Scale [RSS]) as well as hemodynamic and respiratory changes were assessed. Adequate sedation (RSS ≥ 3) was maintained during ERCP in 75.5 % and 36.8 % of the MMD and midazolam - meperidine group, respectively (P < 0.001). RSS scores were significantly higher in the MMD group (P < 0.001). Intraoperative bispectral index scores were significantly lower in the MMD group (P < 0.001) than in the midazolam - meperidine group. Lower additional (P = 0.001) and total (P = 0.003) doses of midazolam were required in the MMD group. Patients in the MMD group showed lower pain scores (P < 0.001) and higher satisfaction scores (P < 0.001). Desaturation occurred more frequently in the midazolam - meperidine group (11 vs. 1; P = 0.003). The addition of dexmedetomidine to the midazolam - meperidine regimen provided better sedative efficacy and a superior safety profile during ERCP compared with a midazolam - meperidine regimen.This trial was registered at ClinicalTrials.gov Identifier (NCT01404689).