[Three cases of ATP-induced bronchospasm during thoracic endovascular aortic repair].

We report three cases (73-year-old, 69-year-old and 76-year-old men) of bronchospasm induced by adenosine triphosphate (ATP) during thoracic endovascular aortic repair (TEVAR). Severe broncospasm occurred soon after administration of ATP to obtain transient asystole during TEVAR. All three cases were complicated with asthma or chronic obstructive pulmonary disease (COPD) before TEVAR, and airway hyper-reactivity was suspected. One case (73-year-old) required postoperative intensive care to treat bronchospasm, and the other two cases recovered during the operation. The possible mechanism of adenosine-induced bronchoconstriction is selective interaction with active mast cells with subsequent release of preformed and newly formed mediators. Careful attention should be paid when ATP is injected during TEVAR in patients with asthma or COPD.

Effect of divided supplementation of remifentanil on seizure duration and hemodynamic responses during electroconvulsive therapy under propofol anesthesia.

PURPOSE: Although a reduced dose of propofol combined with remifentanil is often used in anesthesia for electroconvulsive therapy (ECT), there have been few studies in which the optimal technique for injection of remifentanil was examined in detail. The aim of this study was to evaluate the effects of single and divided injection of remifentanil combined with propofol on seizure duration and hemodynamic responses during ECT. METHODS: Twenty-six ASA I-II patients were enrolled in this study and received a total of 78 ECTs. Each patient received propofol 1.2 mg/kg (group P), remifentanil 1 µg/kg followed by propofol 0.5 mg/kg (group R1), and remifentanil 1 µg/kg followed by propofol 0.5 mg/kg and thereafter remifentanil 2 µg/kg (group R2). Succinylcholine 1 mg/kg was used for muscle paralysis after loss of consciousness. RESULTS: Although mean motor seizure durations were significantly longer in groups R1 and R2 than in group P (P < 0.05), they were similar in groups R1 and R2. Although the percentage increases in mean arterial pressure after ECT were significantly smaller in groups P (P < 0.01) and R2 (P < 0.05) than in group R1, they did not significantly differ between groups P and R2. CONCLUSIONS: Divided use of remifentanil at 1 and 2 µg/kg combined with propofol 0.5 mg/kg produces an acceptable outcome in both seizure duration and hemodynamic stability during ECT compared with the standard hypnotic doses of propofol alone or remifentanil 1 µg/kg followed by propofol 0.5 mg/kg.

Efficacy of the Airtraq(®) laryngoscope with a fiberoptic bronchoscope compared with that of Airtraq(®) alone for tracheal intubation: a manikin study.

PURPOSE: Successful intubation using the Airtraq(®) requires optimal positioning of the glottis in the middle of the viewfinder. If the glottic view cannot be optimized, some glottic manipulation is essential for the Airtraq-assisted successful intubation. We evaluated the efficacy of the combined use of the Airtraq and a fiberoptic bronchoscope (FOB) compared with that of the Airtraq alone for tracheal intubation in simulated airway scenarios. METHODS: Eight anesthesia providers (four staff and four residents) were enrolled in this study. The participants intubated the trachea of the ALS Simulator manikin in five tongue edema scenarios simulating modified Cormack-Lehane grade 1, 2a, 2b, 3, and 4 views and one cervical immobilization scenario. RESULTS: No significant difference in the rate of successful intubation was detected between the combined use and the use of Airtraq alone in all scenarios. However, the duration of intubation attempts with the combined use was significantly shorter in difficult laryngoscopy scenarios (Cormack-Lehane grade 2b-4) (P < 0.01) and were significantly longer in easy laryngoscopy scenarios (grade 1 and 2a) (P < 0.05) than those with Airtraq alone. The rate of successful intubation and duration of intubation attempts were similar between the anesthetists and residents in each intubation technique in all scenarios. CONCLUSION: The combined use of Airtraq(®) and a FOB enables rapid intubation in simulated difficult airway scenarios compared with intubation using Airtraq alone, and the speed of intubation performed by anesthetists and residents is similar in all airway scenarios.

[Case of laryngeal edema occurring after tracheal extubation presumably due to antihypertensive medications].

A 61-year-old woman underwent microlaryngeal surgery for a vocal cord polyp. Anesthesia was induced with propofol, and vecuronium was given after loss of consciousness. The trachea was intubated smoothly with a Portex tracheal tube with a 6.0 mm in inner diameter and the cuff was inflated to the minimal occlusion volume. Anesthesia was maintained with O2-air-sevoflurane. The surgical procedure was completed without any troubles. Immediately after tracheal extubation, she developed dyspnea with stridor. As marked laryngeal edema was found by direct vision with the aide of a laryngoscope, reintubation was performed and methylprednisolone was administered intravenously. She was extubated on the next day, after confirmation of the tracheal tube cuff leak following the reduction in the cuff pressure. At this time, fiberoptic bronchoscopy revealed that the laryngeal edema had disappeared. For the past history, she had taken amlodipine for 10 years and candesertan for 2 months, and had often experienced dyspnea. It should be kept in mind that preoperative antihypertensive medications might have an impact on occurrence of perioperative laryngeal edema.

A comparison of the failure times of pulse oximeters during blood pressure cuff-induced hypoperfusion in volunteers.

Important information may not be obtained if the pulse oximetry signal is lost during inflation of a cuff for blood pressure measurement, particularly in patients with hemodynamic instability. In the present study, we compared the failure times of pulse oximeters during cuff-induced hypoperfusion in volunteers. A pulse oximeter sensor was attached to the index finger, and a blood pressure cuff was attached to the same arm of each volunteer. MasimoSET Radical (Masimo), Nellcor N-395 (N-395), Nellcor N-20PA, and Nellcor D-25 were tested. To evaluate the failure time of each pulse oximeter, time to peak of cuff pressure, time to loss of signal, time to recovery of signal, and failure interval were measured. All measurements were performed three times for each pulse oximeter and were averaged. There were no differences in hemodynamic measurements among the groups. Time to loss of signal was longer in Masimo than the other pulse oximeters. Masimo and N-395 showed significantly shorter times to recovery of signal than those of the other two pulse oximeters. Failure interval was in the order of Masimo << N-395 < Nellcor D-25 = Nellcor N-20PA. Masimo did not lose a signal as rapidly as the other oximeters studied. Masimo was similar in performance to the N-395 at providing useful data sooner than conventional technology after a loss of the signal. These observations suggest that data will be more available with fewer false-positive alarms when using the Masimo oximeter followed by the N-395 when compared with conventional oximeters.