Effect of perioperative intravenous ibuprofen versus acetaminophen on postoperative opioid consumption and pain after general anesthesia: a systematic review and meta-analysis with trial sequential analysis of randomized controlled trials.

Background: Ibuprofen and acetaminophen are widely used as adjuvant analgesics for postoperative pain. This meta-analysis compared the effects of intravenous (IV) ibuprofen and acetaminophen on postoperative opioid consumption and pain intensity after general anesthesia. Methods: PubMed/MEDLINE, EMBASE, and Cochrane Library databases were searched to identify relevant studies published up to May 2023. Randomized controlled trials (RCTs) comparing the effects of perioperative IV ibuprofen and acetaminophen on postoperative opioid consumption and pain after general anesthesia were included in the meta-analysis and trial sequential analysis (TSA). Results: Eight studies with 494 participants were included. Compared to IV acetaminophen, IV ibuprofen significantly reduced 24 h opioid consumption, presented as morphine equivalents (mean difference [MD]: -6.01 mg, 95% CI [-8.60, -3.42], P < 0.00001, I2 = 55%), and pain scores (on a scale of 0-10) at 4-6 h (MD: -0.83, 95% CI [-1.29, -0.37], P = 0.0004, I2 = 65%) and 12 h (MD: -0.38, 95% CI [-0.68, -0.08], P = 0.01, I2 = 11%) postoperatively. These results were statistically significant in TSA. Pain scores at 24 h postoperatively and side effects were not significantly different between the two groups in the meta-analysis, and TSA revealed that the sample size was too small to adequately evaluate the effects, requiring further studies for conclusive results. Conclusions: Perioperative IV ibuprofen reduced 24 h opioid consumption and pain severity up to 12 h postoperatively compared to acetaminophen. Additional research is required to assess pain intensity beyond 12 h and side effects.

Effect of 10 Minutes of Prewarming and Prewarmed Intravenous Fluid Administration on the Core Temperature of Patients Undergoing Transurethral Surgery under General Anesthesia.

Background: Patients undergoing transurethral urologic procedures using bladder irrigation are at increased risk of perioperative hypothermia. Thirty minutes of prewarming prevents perioperative hypothermia. However, its routine application is impractical. We evaluated the effect of 10 minutes of prewarming combined with the intraoperative administration of warmed intravenous fluid on patients' core temperature. Methods: Fifty patients undergoing transurethral bladder or prostate resection under general anesthesia were included in this study and were randomly allocated to either the control group or the prewarming group. Patients in the prewarming group were warmed for 10 minutes before anesthesia induction with a forced-air warming device and received warmed intravenous fluid during operations. The patients in control group did not receive preoperative forced-air warming and were administered room-temperature fluid. Participants' core body temperature was measured on arrival at the preoperative holding area (T0), on entering the operating room, immediately after anesthesia induction, and in 10-minute intervals from then on until the end of the operation (Tend), on entering PACU, and in 10-minute intervals during the postanesthesia care unit stay. The groups' incidence of intraoperative hypothermia, change in core temperature (T0 - Tend), and postoperative thermal comfort were compared. Results: The incidence of hypothermia was 64% and 29% in the control group and prewarming group, respectively (P = 0.015). Change in core temperature was 0.93 ± 0.3 °C and 0.55 ± 0.4 °C in the control group and prewarming group, respectively (P = 0.0001). Thermal comfort was better in the prewarming group (P = 0.004). Conclusions: Ten minutes of prewarming combined with warmed intravenous fluid significantly decreased the incidence of intraoperative hypothermia and resulted in better thermal comfort in patients undergoing transurethral urologic surgery under general anesthesia.

Secondary migration of a pre-existing central venous catheter due to a Swan-Ganz catheter insertion - A case report.

BACKGROUND: The entanglement of multiple central venous catheters is a rare and seriouscomplication. The Swan-Ganz catheter is a responsible for various cases. CASE: A 66-year-old male patient was under general anesthesia for a coronary artery bypassgraft surgery. As he had a pre-existing Perm catheter in the right subclavian vein, a SwanGanz catheter was inserted into the left internal jugular vein. Chest radiograph after catheterplacement revealed that the Perm catheter had migrated to the left brachiocephalic vein.The surgeon attempted to reposition it manually, but postoperative radiograph showed thatit had rolled into a loop. On postoperative day 1, radiological intervention was performed tountangle the loop, which was successful. CONCLUSIONS: After placing a Swan-Ganz catheter in patients with a pre-existing central venous catheter, the presence of entanglement should be assessed. In such cases, radiology-guided correction is recommended, as a blind attempt to disentangle can aggravate thecondition.

Psychogenic coma after general anesthesia with remimazolam and remifentanil -a case report.

BACKGROUND: Delayed emergence from general anesthesia is associated with life-threatening conditions with pharmacological, neurological, metabolic, and rarely, psychiatric causes. This case report was presented to report psychogenic coma after recovery from anesthesia with remimazolam and remifentanil. CASE: An elderly woman was unresponsive after recovery from anesthesia with remimazolam and remifentanil. Physical examination, laboratory testing, and radiographic imaging did not reveal any obvious organic causes. Pharmacological or metabolic abnormalities were not found. Absence of those causes strongly suggests that prolonged unconsciousness is related to psychiatric origin. The patient spontaneously regained consciousness after 48 h without any neurological complications. CONCLUSIONS: Anesthesiologists should be aware of the possibility of psychogenic coma for patients with unexplained delay in emergence from anesthesia after the exclusion of other causes.

Comparison of the Effects of Propofol and Sevoflurane Anesthesia on Optic Nerve Sheath Diameter in Robot-Assisted Laparoscopic Gynecology Surgery: A Randomized Controlled Trial.

Optic nerve sheath diameter (ONSD) is used as a surrogate parameter for intracranial pressure. This study was conducted to evaluate the effect of the anesthetics (sevoflurane and propofol) on ONSD in women undergoing robotic surgery. The 42 patients who were scheduled for robot-assisted gynecology surgery were randomly allocated to the sevoflurane group or the propofol group. ONSD was recorded at 10 min after the induction of anesthesia (T0); 5 min, 20 min, and 40 min after carbon dioxide pneumoperitoneum was induced and the patients were put in a steep Trendelenburg position (T1, T2, and T3, respectively); and at skin closure after desufflation of the pneumoperitoneum (T4). Patients were observed for postoperative nausea and vomiting (PONV) during the immediate postoperative period. The propofol group had significantly lower ONSD than the sevoflurane group at T3. Mean ONSD values continuously increased from T0 to T3 in both groups. Two patients in the sevoflurane group experienced PONV. This study suggests that propofol anesthesia caused a lower increase in ONSD than sevoflurane anesthesia.

Anesthesia in a Patient with Potocki-Lupski Syndrome.

INTRODUCTION: Potocki-Lupski syndrome (PTLS) is a rare disease caused by the duplication of a small segment of chromosome 17 (17p11.2). The clinical presentation of this syndrome is quite variable and includes hypotonia, failure to thrive, oropharyngeal dysphagia, developmental delay, and behavioral abnormalities. In addition, congenital heart disease, sleep apnea, and mildly dysmorphic features are common and should be considered during anesthetic management. However, because of the rarity and newness of the syndrome, there are few reports on the anesthetic care of patients with PTLS. Case Report. We report a case of a 4-year-old girl diagnosed with this syndrome who underwent general anesthesia for exotropia surgery. The patient exhibited micrognathia; a mild decrease in muscle tone; and a developmental delay in motor, speech, and cognition. She had a history of swallowing incoordination and gastroesophageal reflux. No abnormalities were found on a preoperative echocardiography. A videolaryngoscope was used for tracheal intubation, and the state of neuromuscular blockade was monitored in addition to standard monitoring. Anesthesia was maintained with sevoflurane and remifentanil. The patient recovered without any adverse events. CONCLUSION: As PTLS patients may have several malformations, preanesthetic evaluation is important. Preoperative echocardiography and cardiologic consultations are required. It is desirable to prepare for the risk of difficult airway and pulmonary aspiration. Postoperatively, close monitoring is needed to prevent airway compromise.

The influence of positive end-expiratory pressure (PEEP) in predicting fluid responsiveness in patients undergoing one-lung ventilation.

Background: Dynamic preload parameters such as pulse pressure variation (PPV) and stroke volume variation (SVV) have widely been used as accurate predictors for fluid responsiveness in patients under mechanical ventilation. To circumvent the limitation of decreased cyclic change of intrathoracic pressure, we performed an intermittent PEEP challenge test to evaluate whether PPV or SVV can predict fluid responsiveness during one-lung ventilation (OLV). Methods: Forty patients undergoing OLV were analyzed. Baseline hemodynamic variables including PPV and SVV and respiratory variables were recorded after chest opening in lateral position under OLV (T1). Five minutes after application of PEEP 10 cmH2O, the parameters were recorded (T2). Thereafter, PEEP was withdrawn to 0 cmH2O for 5 minutes (T3), and fluid loading was performed with balanced crystalloid solution 6 mL/kg of ideal body weight for 5 minutes. Five minutes after completion of fluid loading, all variables were recorded (T4). The patient was classified as fluid responder if SV increased ≥10% after fluid loading and as non-responder if SV increased <10%. Results: Prediction of fluid responsiveness was evaluated with area under the receiver operating characteristic (ROC) curve (AUC). Change in stroke volume variation (ΔSVV) showed AUC of 0.9 (P < 0.001), 95% CI = 0.82-0.99, sensitivity = 88%, specificity = 82% for discrimination of fluid responsiveness. Change in pulse pressure variation (ΔPPV) showed AUC of 0.88 (P < 0.001), 95% CI = 0.78-0.97, sensitivity = 83%, specificity = 72% in predictability of fluid responsiveness. Cardiac index and stroke volume were well maintained after PEEP challenge in non-responders while they increased in responders. Conclusions: ΔPPV and ΔSVV induced by PEEP challenge are reliable parameters to predict fluid responsiveness as well as very good predictors of fluid unresponsiveness during OLV.

Efficacy of intermittent epidural dexamethasone bolus for zoster-associated pain beyond the acute phase.

Herpes zoster develops when latent varicella zoster virus is reactivated in the trigeminal or dorsal root ganglions. Zoster-associated pain (ZAP) is neuropathic pain caused by the herpes zoster virus. Histological studies of postherpetic neuralgia patients suggest that inflammation is involved in ZAP. The effectiveness of local anesthetic and steroid epidural injections in ZAP patients has been reported. However, most studies included patients with acute herpes zoster, and the safety and therapeutic effects of different doses of epidural steroids in ZAP patients remain elusive. In this study, we randomly assigned 42 patients with severe ZAP beyond the acute phase, as determined by a numeric rating scale (NRS) score ≥7, to receive continuous epidural infusion of local anesthetics with either a one-time 5-mg dose or intermittent repeated doses (15 mg total) of dexamethasone. We found that intermittent repeated epidural dexamethasone bolus resulted in reduced NRS scores and an increased likelihood of complete remission in ZAP patients without any adverse effects. Thus, our results suggest that intermittent repeated epidural dexamethasone administration is safe and effective for treatment of ZAP beyond the acute phase.

Risk factors of postoperative major adverse cardiac events after radical cystectomy: implication of diastolic dysfunction.

Radical cystectomy, which is a standard treatment of muscle invasive and high-grade non-invasive bladder tumour, is accompanied with high rates of postoperative complications including major adverse cardiac events (MACE). Diastolic dysfunction is associated with postoperative complications. We evaluated perioperative risk factors including diastolic dysfunction related with MACE within 6 months after radical cystectomy. The 546 patients who underwent elective radical cystectomy were included. Diastolic dysfunction was defined as early transmitral flow velocity (E)/early diastolic mitral annulus velocity (e') > 15. Logistic regression analysis, Kaplan-Meier survival analysis and log-rank test were performed. MACE within 6 months after radical cystectomy developed in 43 (7.9%) patients. MACE was related with female (odds ratio 2.546, 95% confidence interval 1.166-5.557, P = 0.019) and diastolic dysfunction (odds ratio 3.077, 95% confidence interval 1.147-8.252, P = 0.026). The 6-month mortality were significantly higher in the MACE group, and hospital stay and intensive care unit stay were significantly longer in the MACE group compared to the non-MACE group. Accordingly, preoperative diastolic dysfunction (E/e' > 15) was related with postoperative MACE and MACE was related with 6-month survival after radical cystectomy. These results suggest that preoperative diastolic dysfunction can provide useful information on postoperative complications.

Correction to: Mitral regurgitation detected during the intraoperative period after atrial septal defect closure: a case report.

The original article [1] contained a typo in author, Joo Hyun Jun's name. This has now been corrected.

Is Tube Thermosoftening Helpful for Videolaryngoscope-Guided Nasotracheal Intubation?: A Randomized Controlled Trial.

BACKGROUND: Thermosoftening of the endotracheal tube (ETT) and telescoping the ETT into a rubber catheter have been suggested as a method for reducing epistaxis during nasotracheal intubation (NTI). However, thermosoftening technique is known to make it difficult to navigate the ETT into trachea without the use of Magill forceps during NTI. The cuff inflation technique has been suggested as an effective alternative to the use of Magill forceps to improve the oropharyngeal navigation of the ETT, irrespective of their stiffness, during direct laryngoscope-guided NTI. We evaluated whether thermosoftening of the ETT telescoped into rubber catheters has an additional benefit in reducing nasal injury. Simultaneously, we also evaluated whether thermosoftening of the ETT worsened orotracheal navigability during cuff inflation-supplemented videolaryngoscope-guided NTI. METHODS: One hundred forty patients were randomly assigned to 1 of the 2 groups depending on whether the ETT was softened by warming or not. The primary outcome was the incidence of epistaxis during NTI. The secondary outcome was nasotracheal navigability of the ETT, assessed by navigation grade and time required for insertion of ETT in each phase (from nose to oropharynx, from oropharynx to glottic inlet aided by cuff inflation if needed, and from glottic inlet to trachea). RESULTS: The ETTs were successfully inserted through the selected nostril of all 140 patients. In the thermosoftening group, the incidence and severity of epistaxis was significantly lower (7% vs 51%; difference of 44.2%; 95% confidence interval, 29.9%-56.2%; P < .001), and the ETT passed through the nasal cavity with lower resistance (P = .001) and less time (P < .001) when compared to the control group. No difference was found in the ease of ETT insertion (navigation grade and time required) from the oropharynx to the glottic inlet (P > .99 and P = .054, respectively) and from the glottic inlet to the trachea (P > .99 and P = .750, respectively) between the 2 groups. In both groups, all ETTs could be navigated into the trachea without the use of Magill forceps. CONCLUSIONS: Supplemented with cuff inflation during videolaryngoscope-guided NTI, thermosoftening of the ETT telescoped into rubber catheters has a substantial benefit because it significantly reduces the incidence of epistaxis without worsening the oropharyngeal navigability of the ETT.

Mitral regurgitation detected during the intraoperative period after atrial septal defect closure: a case report.

BACKGROUND: Atrial septal defect (ASD) is a congenital cardiac defect often diagnosed in adult patients. Mitral regurgitation (MR) observed in ASD patients mostly improves after ASD closure. However, a subset of adult ASD patients present new-onset MR or aggravation of preexisting MR after ASD closure. Intraoperative MR aggravation after surgical ASD closure is a rare occurrence which has not been reported in the literature to date. CASE PRESENTATION: A 54-year-old woman was referred to our center due to large secundum ASD with a diameter of 17 mm which was incidentally detected on pre-operative echocardiography at a local clinic. Surgical repair of ASD under mini-thoracotomy was performed. After completion of the operation, intra-operative transesophageal echocardiography showed newly developed Grade II MR which subsequently deteriorated to severe level on postoperative day 3. Because the patient was asymptomatic, we decided to observe closely and treat conservatively with diuretics. Thereafter, echocardiography was evaluated on postoperative day 10 and MR disappeared to trivial level. CONCLUSIONS: Intraoperative MR aggravation is a rare complication following ASD closure. The possibility of MR aggravation should be evaluated in all ASD patients prior to surgery. This case highlights the importance of mitral leaflet examination after ASD closure for early detection of MR.

Efficacy of forced-air warming and warmed intravenous fluid for prevention of hypothermia and shivering during caesarean delivery under spinal anaesthesia: A randomised controlled trial.

BACKGROUND: Peri-operative hypothermia and shivering are frequent events in patients during caesarean delivery under spinal anaesthesia. OBJECTIVE: We assessed the efficacy of combined pre-anaesthetic forced-air warming in combination with warmed intravenous fluid infusion for preventing hypothermia and shivering during caesarean delivery under spinal anaesthesia. DESIGN: A randomised controlled study. SETTING: A tertiary care teaching hospital from July 2017 to April 2018. PATIENTS: A total of 50 pregnant women, American Society of Anaesthesiologists physical status 2, aged 20 to 45 years, scheduled for caesarean delivery under spinal anaesthesia. INTERVENTION: Patients were enrolled and randomised into two groups: an active warming group (n = 25), which received combined pre-anaesthetic whole body forced-air warming for 15 min and prewarmed intravenous fluids, and a control group, which received no active warming or warmed fluids (C group; n = 25). Spinal anaesthesia was induced with 10 mg bupivacaine containing fentanyl (10 µg). MAIN OUTCOME MEASURES: Tympanic membrane temperature and shivering severity were measured at baseline and every 10 min during surgery, and then every 10 min for 1 h postoperatively. Neonatal outcomes (tympanic membrane temperature at birth, umbilical venous blood pH, Apgar score) were also recorded. RESULTS: The incidences of peri-operative hypothermia (0 vs. 48%, P < 0.001) and shivering (22 vs. 52%, P = 0.031) were significantly lower in the active warming than in the C group. The maximum temperature change was also significantly lower in the active warming than in the C group. Maternal thermal comfort scores were higher in the active warming than in the C group. Neonatal parameters were not significantly different between the groups. CONCLUSION: The combination of pre-anaesthetic forced-air warming and warmed intravenous fluid infusions appears to be effective for preventing hypothermia and shivering during caesarean delivery under spinal anaesthesia. TRIAL REGISTRATION: This trial was registered with Clinical Trials.gov (identifier: NCT03256786).

Effect of pre-warming on perioperative hypothermia during holmium laser enucleation of the prostate under spinal anesthesia: a prospective randomized controlled trial.

BACKGROUND: The purpose of this study is to assess whether the application of preoperative forced air warming set to high temperature (> 43 °C) for brief period can increase temperature on admission to the postanesthesia care unit (PACU) and prevent hypothermia or shivering during holmium laser enucleation of the prostate performed under spinal anesthesia. METHODS: Fifty patients were enrolled were assigned randomly to receive passive insulation (control group, n = 25) or forced-air skin surface warming for 20 min before spinal anesthesia (pre-warming group, n = 25). The primary outcome was temperature at PACU admission. RESULTS: The pre-warming group had a significantly higher temperature on admission to the PACU than the control group (35.9 °C [0.1] vs 35.6 °C [0.1], P = 0.023; 95% confidence interval of mean difference, 0.1 °C-0.5 °C). The trend of decreasing core temperature intraoperatively was not different between groups (P = 0.237), but intraoperative core temperature remained approximately 0.2 °C higher in the pre-warming group (P = 0.005). The incidence of hypothermia on admission to the PACU was significantly lower in the pre-warming group (56% vs 88%, P = 0.025). Shivering occurred in 14 patients in the control group, and 4 patients in the pre-warming group (P = 0.007). CONCLUSION: Brief pre-warming at 45 °C increased perioperative temperature and decreased the incidence of hypothermia and shivering. However, it was not sufficient to modify the decline of intraoperative core temperature or completely prevent hypothermia and shivering. Continuing pre-warming to immediately before induction of spinal anesthesia or combining pre-warming with intraoperative active warming may be necessary to produce clearer thermal benefits in this surgical population. TRIAL REGISTRATION: This trial was registered with Clinicaltrials.gov, NCT03184506 , 5th June 2017.

Effect of Mannitol on Ultrasonographically Measured Optic Nerve Sheath Diameter as a Surrogate for Intracranial Pressure During Robot-Assisted Laparoscopic Prostatectomy with Pneumoperitoneum and the Trendelenburg Position.

INTRODUCTION: CO2 pneumoperitoneum and the steep Trendelenburg position during robot-assisted laparoscopic prostatectomy (RALP) can increase intracranial pressure (ICP). Mannitol is widely used to treat increased ICP. However, no studies to date have specifically evaluated the effect of mannitol on ICP in patients undergoing RALP. Ultrasonographic measurement of the optic nerve sheath diameter (ONSD) is considered a reliable technique to noninvasively evaluate the ICP. Therefore, this study compared ONSDs as a surrogate for ICP before and after mannitol administration in prostate cancer patients undergoing RALP. METHODS: Mannitol (0.5 g/kg) was administered after pneumoperitoneum establishment and shifting to the Trendelenburg position. ONSDs were measured at six predetermined time points: 10 minutes after anesthesia induction (T0); 5 minutes after pneumoperitoneum and the Trendelenburg position before mannitol administration (T1); 30 minutes (T2), 60 minutes (T3), and 90 minutes (T4) after completion of mannitol administration during pneumoperitoneum and the Trendelenburg position; and at skin closure in the supine position (T5). Moreover, intraoperative hemodynamic and respiratory variables were evaluated simultaneously. RESULTS: Thirty-six patients were analyzed. ONSDs were significantly lower at T2, T3, and T4 than at T1 (all p < 0.001), with the greatest decrease observed at T4 compared with T1 (4.46 ± 0.2 mm vs 4.81 ± 0.3 mm, p < 0.001). Regional cerebral oxygen saturation, cardiac output, corrected flow time, peak velocity, body temperature, arterial CO2 partial pressure, peak airway pressure, plateau airway pressure, dynamic compliance, and static compliance were not significantly different during pneumoperitoneum and the Trendelenburg position; however, mean arterial blood pressure and heart rate were significantly different. CONCLUSIONS: Mannitol decreases the ONSD in patients undergoing RALP with CO2 pneumoperitoneum and the steep Trendelenburg position. This result provides useful information on the beneficial effects of mannitol administration on prostate cancer patients who may develop increased ICP during RALP.

Impact of anesthetic agents on overall and recurrence-free survival in patients undergoing esophageal cancer surgery: A retrospective observational study.

Given that surgical stress response and surgical excision may increase the likelihood of post-surgery cancer dissemination and metastasis, the appropriate choice of surgical anesthetics may be important for oncologic outcomes. We evaluated the association of anesthetics used for general anesthesia with overall survival and recurrence-free survival in patients who underwent esophageal cancer surgery. Adult patients (922) underwent elective esophageal cancer surgery were included. The patients were divided into two groups according to the anesthetics administered during surgery: volatile anesthesia (VA) or intravenous anesthesia with propofol (TIVA). Propensity score and Cox regression analyses were performed. There were 191 patients in the VA group and 731 in the TIVA group. In the entire cohort, VA was independently associated with worse overall survival (HR 1.58; 95% CI 1.24-2.01; P < 0.001) and recurrence-free survival (HR 1.42; 95% CI 1.12-1.79; P = 0.003) after multivariable analysis adjustment. Similarly, in the propensity score matched cohorts, VA was associated with worse overall survival (HR 1.45; 95% CI 1.11-1.89; P = 0.006) and recurrence-free survival (HR 1.44; 95% CI 1.11-1.87; P = 0.006). TIVA during esophageal cancer surgery was associated with better postoperative survival rates compared with volatile anesthesia.

Effective dose of dexmedetomidine to induce adequate sedation in elderly patients under spinal anesthesia.

BACKGROUND: During sedation with dexmedetomidine, a dose adjustment may be needed based on the invasiveness of the procedure, the patient's general condition, and their age. We aim here to determine the effective dose (ED) of dexmedetomidine to induce an adequate depth of sedation in elderly patients undergoing spinal anesthesia. METHODS: In this study, 47 patients aged 65 years or older, American Society of Anesthesiologists physical status I or II, undergoing spinal anesthesia were included. Patients were randomly allocated into group I, II, III, IV or V according to the dexmedetomidine loading dose of 0.1, 0.3, 0.5, 0.7 and 1.0 µg/kg, respectively. After spinal anesthesia, the assigned loading dose of dexmedetomidine was infused intravenously for 10 minutes, after which infusion was maintained at a rate of 0.3 µg/kg/h for the next 10 minutes in all groups. We assessed the depth of sedation with the Ramsay sedation scale every five minutes and measured vital signs and the oxygen saturation. The ED50 and ED95 of dexmedetomidine to obtain adequate sedation (Ramsay sedation score ≥ 3) upon the completion of the loading dose were calculated with logistic regression. RESULTS: The ED50 and ED95 of dexmedetomidine for adequate sedation were 0.29 µg/kg (95% confidence intervals [CI] 0.14-0.44) and 0.86 µg/kg (95% CI 0.52-1.20), respectively. Hypotension was frequent in groups IV, V compared to groups I, II, III (31.6 vs. 3.6%, P = 0.013). CONCLUSIONS: ED95 of dexmedetomidine loading dose for adequate sedation is 0.86 µg/kg. However, dose higher than 0.5 µg/kg can lead to hemodynamic instability.