Duration of the action of rocuronium in patients with BMI of less than 25: An observational study.

BACKGROUND: The duration of rocuronium in patients with BMI more than 30 kg m is prolonged. Whether the reverse is true when BMI is less than 18.5 kg m is unclear. OBJECTIVE: The objective of this study was to investigate whether a BMI less than 25 kg m affects the duration of rocuronium in doses adjusted for actual body weight. DESIGN: A prospective, observational, single-centre study. SETTING: The operating room of a teaching hospital from 1 June 2008 to 30 June 2015. PATIENTS: Thirty patients with American Society of Anesthesiologists physical status I or II who were scheduled to undergo elective surgery (BMI < 25 kg m, aged 23 to 74 years) maintained by 0.7 minimum alveolar concentration sevoflurane and remifentanil. MAIN OUTCOME MEASURES: Repetitive train-of-four stimulation was applied and contractions of the adductor pollicis muscle were recorded. Duration of the initial dose of rocuronium (D1) was defined as the time from injection of rocuronium 0.6 mg kg to return of first twitch height to 25% of the control. Duration of additional doses (D2) was the time from a supplement of 0.15 mg kg rocuronium to return of first twitch height to 25% of the control. The relationship between D1 or D2 and BMI was examined using linear regression analysis. RESULTS: Linear regression analysis revealed a significant correlation between duration of initial dose and BMI (R = 0.246; P = 0.00531). A significant correlation between the duration of the additional dose and BMI was also found (R = 0.316; P = 0.00122). CONCLUSION: The lower the BMI, the shorter the duration of rocuronium at initial and additional doses determined by the actual body weight in adult patients with a BMI less than 25 kg m. TRIAL REGISTRATION: www.umin.ac.jp/ctr/index/htm with registry number UMIN 00009337 and UMIN 000015407.

[Evaluation of the Effects of Remifentanil Doses on Hemodynamics and Perfusion Index at the Onset of Pneumoperitoneum during Laparoscopic Surgery].

BACKGROUND: The aim of this study was to investigate whether changes in perfusion index (PI) correlate with non-invasive haemodynamic parameters (HR, BP) following the onset of pneumoperitoneum under two doses (moderate-dose (MD) and high-dose (HD)) of remifentanil and to compare its reliability. METHODS: We divided 33 patients who were scheduled for laparoscopic surgery under general anesthesia into two groups according to the dose of continuously infused remifentanil: moderate dose 0.5 µg x kg(-1) x min(1) (MD group, n = 16) and high dose 1.0 µg x kg(-1) x min(-1) (HD group, n = 17). Non-invasive blood pressure (NIBP), HR, and PI were measured before the start of surgery (time 1), after the start of surgery (time 2), before the start of pneumoperitoneum (time 3), and 1 min after the stable state of pneumoperitoneum (time 4). RESULTS: PI decreased from the baseline after pneumoperitoneum in MD group, on the other hand PI did not change in HD group. Between the two groups, the magnitude of the PI changes was statistically different although MBP and HR were not statistically different CONCLUSIONS: PI may be a reliable and easier alternative to conventional haemodynamic parameters for detection of stress response to pneumoperitoneum during remifentanil anaesthesia in adult patients.

The novel prostaglandin I2 mimetic ONO-1301 escapes desensitization in an antiplatelet effect due to its inhibitory action on thromboxane A2 synthesis in mice.

ONO-1301 [(E)-[5-[2-[1-phenyl-1-(3-pyridyl)methylidene-aminooxy]ethyl]-7,8-dihydronaphthalene-1-yloxy]acetic acid] is a novel prostaglandin (PG) I2 mimetic with inhibitory activity on the thromboxane (TX) A2 synthase. Interestingly, ONO-1301 retains its inhibitory effect on platelet aggregation after repeated administration, while beraprost, a representative agonist for the PGI2 receptor (IP), loses its inhibitory effect after repeated administration. In the present study, we intended to clarify the mechanism by which ONO-1301 escapes desensitization of an antiplatelet effect. In platelets prepared from wild-type mice, ONO-1301 inhibited collagen-induced aggregation and stimulated cAMP production in an IP-dependent manner. In addition, ONO-1301 inhibited arachidonic acid-induced TXA2 production in platelets lacking IP. Despite the decrease in stimulatory action on cAMP production, the antiplatelet effect of ONO-1301 hardly changed after repeated administration for 10 days in wild-type mice. Noteworthy, beraprost could retain its antiplatelet effect after repeated administration in combination with a low dose of ozagrel, a TXA2 synthase inhibitor. Therefore, we hypothesized that chronic IP stimulation by beraprost induces an increase in TXA2 production, leading to reduction in the antiplatelet effect. As expected, repeated administration of beraprost increased the plasma and urinary levels of a TXA2 metabolite, while ONO-1301 did not increase them significantly. In addition, beraprost could retain the ability to inhibit platelet aggregation after repeated administration in mice lacking the TXA2 receptor (TP). These results indicate that TP-mediated signaling participates in platelet desensitization against IP agonists and that simultaneous inhibition of TXA2 production confers resistance against desensitization on IP agonists.

Preoperative morphological analysis by transesophageal echocardiography and predictive value of plasma landiolol concentration during systolic anterior motion mitral valve repair : a report of three cases.

We report three cases with systolic anterior motion (SAM) after mitral valve plasty. Preoperative mitral valve morphology is a risk factor for SAM. The morphological characteristics of SAM have been revealed in several studies. We found a small distance between coaptation and the interventricular septum in all cases, and cases 2, and 3 had a low AL/PL ratio, whereas case 3 had a large PML, which was revealed by transesophageal echocardiography. With the use of 3D transesophageal echocardiography, when mitral valve prolapse was investigated, in all three cases, it was easy to specify lesions. The issue for the future is 3D analysis when SAM is occurring.

[Case report of cardiac arrest during carotid body tumor resection].

We report a case of 30-second cardiac arrest that occurred during carotid body tumor resection due to the carotid sinus reflex. The patient was a 20-year-old man diagnosed with a carotid body tumor and scheduled for tumor resection. General anesthesia was induced and maintained with target controlled infusion of propofol. Analgesia was achieved with continuous administration of remifentanil. When the surgery was initiated, 1% lidocaine 3 ml was locally injected into the carotid bifurcation. When surgery was initiated in the neck region, the patient developed sudden cardiac arrest. Chest compression was immediately initiated, and atropine 0.5 mg was administered; subsequently circulation was restored. Surgery was resumed after placing a temporary pacemaker through the left subclavian vein. The surgery was successfully performed without any other bradycardia complications, and the patient recovered from general anesthesia without sequelae. Thus, the findings indicate the importance of considering the pacemaker placement before carotid body tumor resection.

[Intraoperative evaluation of visceral arteries by transesophageal echocardiography during aortic fenestration].

76-year-old man was diagnosed with DeBakey type IIIb acute aortic dissection, for which he underwent axillo-femoral bypass surgery. Two days postoperatively, hematochezia developed suddenly. Laboratory data revealed AST 5,088 IU x l(-1), ALT 3,822 IU x l(-1), and CK 27,746 IU x l(-1) suggesting intestinal malperfusion due to stenosis of the celiac artery (CEA) and superior mesenteric artery (SMA). The abdominal aorta and visceral arteries were evaluated by transesophageal echocardiography (TEE). Color Doppler imaging revealed increased blood flow velocity (4.0 m x sec(-1)) in CEA due to the stenosis, while that in SMA was decreased. Open abdominal aortic fenestration was performed. The aorta was clamped at the level of the infra-renal and inferior mesenteric arteries, and the septum between the false and true lumens was resected. On postoperative TEE assessment, CEA stenosis was resolved, and flow velocity was improved (3.0 m x sec(-1)). Color Doppler imaging demonstrated that fenestration resulted in recovery of SMA perfusion. Aortic fenestration is useful in the treatment of ischemic complications of aortic dissection. Its advantages include minimal invasiveness and short operative time. Bypass surgery and reoperation were avoided by evaluating visceral arteries by TEE in the case reported here.

[Diagnosing pneumothorax by using transthoracic lung ultrasonography during one lung ventilation].

BACKGROUND: Ultrasound guided neuraxial block or central venous puncture is now becoming popular in our anesthesia practice to reduce the risk of complications. Pneumothorax is a rare, but possible complication related to these interventions even if the ultrasound is used. However, the pneumothorax itself can also be diagnosed by the ultrasound. We therefore examined the efficacy of ultrasound for diagnosing pneumothorax during lung surgery requiring one lung ventilation. METHODS: In 20 elective surgery patients, transthoracic lung ultrasonography was performed. The lung sliding, comet-tail artifact, M-mode, lung pulse, and power sliding were used to eliminate pneumothorax, and the reverberation artifact was used as a sign of the pneumothorax. Ultrasound procedure was videotaped for postprocedure analysis. Both sensitivity and specificity were calculated in each case. RESULTS: Lung sliding and M-mode procedure showed high sensitivity and specificity in diagnosing pneumothorax. Reverberation artifact also showed high sensitivity, but its specificity was too low to determine pneumothorax. CONCLUSIONS: Among six ultrasonic lung findings, lung sliding and M-mode procedure are most useful as screening methods of differentiating a pneumothorax.

[A comparison of the single-use i-gel with the reusable laryngeal mask airway Proseal in anesthetized adult patients in Japanese population].

BACKGROUND: The i-gel is a newly developed, cuffless and single-use supraglottic airway device with gastric drain conduit. This study was designed to compare the performance of the i-gel with the reusable LMA Proseal when used during anesthesia in spontaneously breathing adult patients. METHODS: One hundred adult patients were studied in a prospective randomized controlled study. Insertion time, success rate at the first attempt, necessity for finger insertion along with the device, leak pressure, success rate for gastric tube placement, and the incidence of blood staining on removal, sore throat and hoarseness were compared. For statistical analyses, Student's t test, Mann-Whitney's U test, and Fisher's exact test were used where appropriate, and P<0.01 considered significant. RESULTS: I-gel provided significantly faster insertion time (4.4 vs 16 seconds, P < 0.01). Success rates were higher for i-gel, and i-gel requiring no finger insertion with the device. Leak pressure was similar just after insertion, but higher for i-gel after 10 minutes from insertion (36 vs 28 cmH2O, P < 0.01). Success rate for gastric tube placement and the incidence of complications were similar. CONCLUSIONS: Our result indicated that i-gel can be inserted faster without inserting practitioners' finger into patient oral cavity. Leak pressure was sufficient for clinical use in spontaneous breathing anesthetized adult patients.

The intrinsic prostaglandin E2-EP4 system of the renal tubular epithelium limits the development of tubulointerstitial fibrosis in mice.

Inflammatory responses in the kidney lead to tubulointerstitial fibrosis, a common feature of chronic kidney diseases. Here we examined the role of prostaglandin E(2) (PGE(2)) in the development of tubulointerstitial fibrosis. In the kidneys of wild-type mice, unilateral ureteral obstruction leads to progressive tubulointerstitial fibrosis with macrophage infiltration and myofibroblast proliferation. This was accompanied by an upregulation of COX-2 and PGE(2) receptor subtype EP(4) mRNAs. In the kidneys of EP(4) gene knockout mice, however, obstruction-induced histological alterations were significantly augmented. In contrast, an EP(4)-specific agonist significantly attenuated these alterations in the kidneys of wild-type mice. The mRNAs for macrophage chemokines and profibrotic growth factors were upregulated in the kidneys of wild-type mice after ureteral obstruction. This was significantly augmented in the kidneys of EP(4)-knockout mice and suppressed by the EP(4) agonist but only in the kidneys of wild-type mice. Notably, COX-2 and MCP-1 proteins, as well as EP(4) mRNA, were localized in renal tubular epithelial cells after ureteral obstruction. In cultured renal fibroblasts, another EP(4)-specific agonist significantly inhibited PDGF-induced proliferation and profibrotic connective tissue growth factor production. Hence, an endogenous PGE(2)-EP(4) system in the tubular epithelium limits the development of tubulointerstitial fibrosis by suppressing inflammatory responses.

Thromboxane A2 and prostaglandin F2alpha mediate inflammatory tachycardia.

Systemic inflammation induces various adaptive responses including tachycardia. Although inflammation-associated tachycardia has been thought to result from increased sympathetic discharge caused by inflammatory signals of the immune system, definitive proof has been lacking. Prostanoids, including prostaglandin (PG) D(2), PGE(2), PGF(2alpha), PGI(2) and thromboxane (TX) A(2), exert their actions through specific receptors: DP, EP (EP(1), EP(2), EP(3), EP(4)), FP, IP and TP, respectively. Here we have examined the roles of prostanoids in inflammatory tachycardia using mice that lack each of these receptors individually. The TXA(2) analog I-BOP and PGF(2alpha) each increased the beating rate of the isolated atrium of wild-type mice in vitro through interaction with TP and FP receptors, respectively. The cytokine-induced increase in beating rate was markedly inhibited in atria from mice lacking either TP or FP receptors. The tachycardia induced in wild-type mice by injection of lipopolysaccharide (LPS) was greatly attenuated in TP-deficient or FP-deficient mice and was completely absent in mice lacking both TP and FP. The beta-blocker propranolol did not block the LPS-induced increase in heart rate in wild-type animals. Our results show that inflammatory tachycardia is caused by a direct action on the heart of TXA(2) and PGF(2alpha) formed under systemic inflammatory conditions.

Ideal body weight-based remifentanil infusion is potentially insufficient for anesthetic induction in mildly obese patients.

We evaluated whether the effect of remifentanil treatment differs between normal weight (NW) patients with real body weight-based remifentanil and mildly obese (Ob) patients with ideal body weight based-remifentanil during short-term anesthetic induction. We enrolled 20 patients aged between 20 and 64 years in each group (NW group: 18.5 kg/m(2) ≤ BMI < 25 kg/m(2); Ob group: BMI ≥ 25 kg/m(2)). Tracheal intubation (TI) was performed after administration of 0.5 µg/kg/min remifentanil for 5 min, including 2 min of antecedent administration, with propofol and rocuronium. Hemodynamic parameters (SBP, DBP, and HR) were measured. Percent changes in hemodynamics resulting from anesthetic induction and TI were calculated, and effect-site concentration (ESC) in each patient was calculated by performing pharmacokinetic simulation. All hemodynamic values in the Ob group after TI were significantly higher than those in the NW group. Percent increases in SBP and HR in the Ob group were significantly higher than the corresponding values in the NW group. ESC of remifentanil at the time of TI in the NW group was higher than that in the Ob group. Remifentanil treatment with anesthetic induction based on the Japanese package insert might have insufficient effects in obese patients.

[Comparison of the Supreme Laryngeal Mask Airway(SLMA), single use, with the reusable Proseal Laryngeal Mask Airway(PLMA) in anesthetized adult Japanese patients].

BACKGROUND: Supreme laryngeal mask airway (SLMA) is a single use, new supraglottic airway device with anatomically designed curved airway conduit. It has second channel for gastric tube insertion. We compared the performance of the SLMA with that of the Proseal LMA (PLMA), the older reusable LMA, during anaesthesia in spontaneously breathing adult patients. METHODS: One hundred adult patients were studied in a prospective randomized controlled study. Insertion time, first attempt success rates, leak pressure, ease of gastric tube placement, and the incidence of blood staining on removal, as well as sore throat and hoarseness were compared. For statistical analyses, Student's t test, Mann-Whitney's U test, and Fisher's exact test were used where appropriate, and P<0.01 considered significant. RESULTS: SLMA provided faster insertion time (11 vs 18 seconds, P<0.01). Leak pressure was higher for PLMA (25 vs 28cmH2O, P<0.01). First attempt success rates, gastric tube placement and the incidence of complications were similar. CONCLUSIONS: Our result indicated that SLMA can be inserted faster without inserting one's finger into patient oral cavity. Leak pressure was lower but acceptable for clinical use in spontaneously breathing anesthetized adult patients.

Perioperative Management of Robotic-Assisted Gynecological Surgery in a Super Morbidly Obese Patient.

We report the perioperative management of a 32-year-old woman with super-morbid obesity (body mass index (BMI) of 60.9 kilograms per meter squared (kg/m2)) who underwent a robotic-assisted total laparoscopic hysterectomy in a hospital that was not specialized for obese patients. She successfully reduced her BMI by 10% using dietary restrictions in five weeks, and her surgery was performed two weeks later by consultation between gynecologists and anesthesiologists. This case demonstrates that the determination of the optimal time for surgery by consultation between physicians is crucial in the care of such a complex patient in hospitals that are not specialized for morbidly obese patients. Weight reduction in the preoperative period should be considered for super-morbid obesity patients with malignant diseases, even if the duration of preoperative optimization is shorter than four to eight weeks.

Dexmedetomidine can stabilize hemodynamics and spare anesthetics before cardiopulmonary bypass.

PURPOSE: We previously confirmed the effectiveness of dexmedetomidine (DEX) for stabilizing hemodynamics as well as sparing anesthetics during anesthetic induction in patients undergoing cardiac surgery (Kunisawa et al. in J Clin Anesth 21:194-199, 1). In this study, we investigated whether these effects of DEX continue until the start of cardiopulmonary bypass (CPB). METHODS: Twenty-two patients with mild to moderate cardiovascular disease were randomized into two groups [DF2 group: DEX dose of 0.7 µg/kg/h after initial dose and effect-site concentration (ESC) of fentanyl of 2 ng/ml; PF4 group: saline and ESC of fentanyl of 4 ng/ml]. Propofol was administered for anesthetic induction and maintenance. Hemodynamics, cardiovascular drugs, ESC of propofol, and cardiovascular responses to skin incision (SI) and sternotomy (St) were measured or calculated. RESULTS: Blood pressure (BP) at the pre-/post-SI periods was higher in the DEX group (137 ± 17/140 ± 16 mmHg) than in the placebo group (85 ± 9/109 ± 24 mmHg). Percent increases in cardiovascular response to SI or St were lower in the DEX group than in the placebo group (for example, 1.9 ± 2.2 vs. 27.4 ± 19.9% in systolic BP due to SI). ESCs of propofol at SI and St in the DEX group were lower than those in the placebo group. CONCLUSIONS: DEX combined with 2 ng/ml fentanyl before CPB can suppress the decrease in blood pressure at the pre- and post-SI periods, can blunt the cardiovascular responses to SI and St, and can spare the required ESC of propofol despite fentanyl concentration, which was half of that in the placebo group.

[Administration of sugammadex to a patient with myasthenia gravis with fade of the train-of-four ratio].

A 50-year-old man (weight 87 kg, height 171 cm) with myasthenia gravis (MG) was scheduled for extended thymectomy under general anesthesia. His preanesthetic train-of-four ratio (T4/T1) was 59%. The first twitch of the train-of-four (T1) was 130% after calibration. We administered rocuronium 10 mg (0.11 mg x kg(-1)) for tracheal intubation. Maximal suppression was achieved in 50 seconds. During the operation, we did continuous infusion of rocuronium to maintain T1 at 10%. We discontinued rocuronium infusion before the end of surgery. In patients with MG, deep levels of neuromuscular block can be achieved with less rocuronium. We hypothesized that the requirement of sugammadex in a patient with MG is less than that in normal patients. Therefore, we administered 0.5 mg x kg(-1) of sugammadex. After 5 min, T4/T1 had reached 54%, but T1 had not reached the control value; therefore, we administered additional 1.5 m x kg(-1) of sugammadex. Subsequently, T1 reached 120%. Patients with MG with fade on T4/T1 require a full dose of sugammadex, identical to the dose administered to normal patients.

[Intubation training survey using four types of laryngoscopes among medical students: a comparison of the Macintosh laryngoscopes, Miller laryngoscopes, Airtraq, and Pentax-AWS Airwayscope].

BACKGROUND: Recently, rigid indirect laryngoscopes with integrated tube guidance such as Pentax-AWS (AWS) and Airtraq (ATQ) are clinically available. They are known to improve the laryngeal view and facilitate intubation compared to the Macintosh laryngoscope (MAC). However, whether these new devices are easy to learn for novice laryngoscopists is not well understood. We surveyed medical students regarding their usefulness in intubation procedure on mannequin. METHODS: Sixty-six medical students with no intubation experience were enrolled. A short instruction including practice for four devices (MAC, Miller laryngoscope (MIL), AWS, and ATQ) was given. Four intubation procedures (one for each device) to the mannequin (Laerdal airway trainer) were performed. The time to place the tube, percentage of glottic opening (POGO), incidence of esophageal intubation and teeth click were recorded. Participants were asked to choose the best device for their use. For statistical analyses, ANOVA and Chi-square tests were used where appropriate, and P < 0.01 considered significant. RESULTS: Time for intubation was significantly longer in ATQ (P < 0.01). POGO was significantly higher in AWS, but lower in MAC (P < 0.01). Complications were fewer in AWS (P < 0.01), and 70% of the participants chose AWS as the best device. CONCLUSION: With minimal instruction including practice, the AWS seemed to achieve safer intubation with better laryngeal view for novice laryngoscopists.

[Case report: a normal dose of rocuronium achieved the desired effect in a short time after the administration of sugammadex during reoperation].

A 69-year-old man with normal renal function underwent resection of a parotid tumor under general anesthesia. For tracheal intubation, rocuronium 0.6 mg x kg(-1) was administered, and for facial nerve stimulation, sugammadex 2 mg x kg(-1) was administered immediately after intubation. The operation time was 3 h. At the end of the surgery, sugammadex 2 mg x kg(-1) was administered again. Bleeding occurred 6 h after the surgery. During the second operation, rocuronium 0.6 mg x kg (-1) was administered for tracheal intubation. Maximal suppression was achieved 1 min 42 s after the administration of rocuronium, and the recovery time was 44 min. The times for both maximal suppression and recovery are similar to those when the same dose of rocuronium was used without sugammadex. The half-life of sugammadex is about 2 h. From the observations in this case, we think that after the completion of approximately 3 half-lives, a normal dose of rocuronium can produce the desired effect without the influence of residual sugammadex present in the plasma.

[Postoperative analgesia of continuous intravenous fentanyl or dexmedetomidine for patients receiving anticoagulant therapy].

BACKGROUND: It is difficult to achieve good postoperative analgesia in patients who undergo abdominal aortic surgery without epidural analgesia and who have a bleeding tendency or are undergoing anticoagulation therapy. Intravenous fentanyl analgesia can be used in such patients, but it occasionally causes respiratory depression. Dexmedetomidine is used to achieve postoperative sedation and analgesia without respiratory depression. We compared the methods used to achieve postoperative analgesia after abdominal aortic surgery. METHODS: In the intravenous fentanyl analgesia group (group F, n = 15), 0.5 microg x kg(-1) x hr(-1) fentanyl infusion was initiated during operation and continued to the next morning. In the intravenous dexmedetomidine group (group D, n = 15), 0.4-0.7 microg x kg(-1) x hr(-1) dexmedetomidine infusion was commenced during the operation and decreased to 0.2-0.7 microg x kg(-1) x hr- in the next morning. In the control group (group C, n = 15), continuous intravenous analgesia was not used. The frequency of analgesic use, Ramsay score, PaCO2 value, and rate of nausea and shivering were evaluated on the next morning. RESULTS: The frequency of analgesic use and Ramsay score were similar in groups F and D. The Paco2 value was higher in group F than group D. CONCLUSIONS: With regard to respiratory depression, intravenous dexmedetomidine analgesia is safer and more useful than intravenous fentanyl analgesia.

Dexmedetomidine was safely used for sedation during spinal anesthesia in a very elderly patient.

We safely administered dexmedetomidine (DEX) for sedation during spinal anesthesia in a very elderly patient. The patient was a 98-year-old woman who had hypertension, renal failure, and first-grade atrioventricular block. She was scheduled to undergo internal fixation for fracture of the femoral neck. Initially, DEX (6.0 µg/kg/h) was administered over 10 min, followed by continuous infusion at a dose of 0.7 µg/kg/h. Consequently, her Ramsay sedation score (RSS) increased to 5, and the patient did not grimace in pain while being turned to the lateral position. Epidural catheterization and spinal anesthesia were performed under sedation without any problem. The DEX dose was adjusted to maintain the RSS within 3-4. The surgical operation was performed smoothly without any problem. Since the hemodynamic condition was stable, administration of ephedrine (5 mg) was required only once during surgery. Percutaneous oxygen saturation was maintained at 98% or more; respiratory rate was within 15-21 tpm, and no ventilatory assistance was required. The maximum predicted plasma concentration (pCp) of DEX was 1.56 ng/mL, and the mean pCp of DEX during surgery was approximately 0.45 ng/mL. We found that DEX can be safely used for sedation during spinal anesthesia in a very elderly patient.

Awake intubation under sedation using target-controlled infusion of dexmedetomidine: five case reports.

We used target-controlled infusion (TCI) of dexmedetomidine (DEX) for awake intubation under sedation in 5 patients who had a risk of pulmonary aspiration or difficult airway. Dexmedetomidine level was escalated stepwise until the patients developed tolerance to laryngoscopy. The target DEX concentrations at the time of intubation were 2.10-5.95 ng/ml and were higher than those clinically used for sedation in the intensive care unit (ICU). Chin lift was applied in 1 case, and therefore no assisted ventilation was required and pulse oxygen saturation was maintained at >98% throughout the procedure. Simple pharmacological interventions for blood pressure changes induced by increased target plasma DEX concentrations were needed in 4 cases. However, hemodynamics was stable, and no cardiovascular drug was needed after tracheal intubation. Conditions at laryngoscopy were excellent in all cases, and conditions at tracheal intubation were good except in 1 case. Reflex to intubation was preserved in all cases, and coughing was observed in all cases. The patients had no memory of discomfort and/or intubation. Although further investigations are needed, this method may be useful for awake intubation under sedation.