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Noninvasive blood-pressure measurement device and pulse oximeter are important for patient monitoring. When these are placed on the same side, cuff inflation sometimes causes measurement failure by pulse oximeter.The present study aimed to compare the pulse oximeter alarm frequency and pulse-wave disappearance duration between noninvasive blood-pressure measurement using the deflation method and that using the linear inflation method.The study included 10 healthy subjects. The cuff for automatic sphygmomanometer was wrapped on one side of the upper arm and for pulse oximeter was attached to the thumb of the same side of upper limbs.The alarm frequency was 0 and 26% using the linear inflation and the deflation methods, respectively. Additionally, the pulse-wave disappearance duration was significantly longer using the deflation method than that using the linear inflation method (10.0 ± 1.5 vs 1.7 ± 0.8 s). With the linear inflation method, this duration was or less 3 s. In the deflation method, an excess pressure of 40 mmHg was used, which caused the alarm to turn on. Additionally, the heart rate was found to influence the alarm occurrence during measurement using the deflation method.Heart rate may influence alarm occurrence during blood-pressure measurement using the step deflation method. Using the linear inflation method, the risks of alarm occurrence and measurement failure are low, even when the pulse oximeter and blood-pressure measurement cuffs are installed on the same side, suggesting that this method is suitable for clinical use.

The characteristics of electroencephalogram (EEG) profiles under general anesthesia may depend on age and type of anesthetic. This study investigated age-related differences in EEG waveforms between three inhalational anesthetics used at the same minimum alveolar concentration (MAC), which indicates the level of analgesia. Patients with American Society of Anesthesiologists physical status I–II were divided into three groups according to age: pediatric (≦ 15 years); adult (16–64 years); and elderly (≧ 65 years). Each group was divided into three subgroups according to the inhalational anesthetic used: sevoflurane, isoflurane, and desflurane. Anesthesia was maintained at 1 MAC, followed by assessment of 95% spectral edge frequency (SEF95) values and amplitude of EEG waveform. The 3 age groups comprised a total of 180 patients. The mean (± SD) EEG waveform amplitude and SEF95 values for sevoflurane in the pediatric, adult, and elderly age groups, respectively, were: 32.9 ± 2.9 µV and 16.7 ± 2.4 Hz; 16.4 ± 3.6 µV and 12.2 ± 1.3 Hz; and 11.0 ± 2.1 µV and 13.6 ± 1.6 Hz. EEG waveform amplitude and SEF95 values were significantly higher in the pediatric group than in the other groups. SEF95 value was higher in the elderly group than in the adult group. Similar results were obtained for isoflurane and desflurane. The amplitude of the EEG waveform and SEF95 values varied with age, even at the same analgesic state in patients under general anesthesia. This age-dependent change in EEG waveform was observed for all three inhalational anesthetics, and should be considered in procedures requiring general anesthesia.

Background Cardiopulmonary resuscitation (CPR) requires immediate start of manual chest compression (MCC) and defibrillation as soon as possible. During dental surgery, CPR could be started in the dental chair considering difficulty to move the patient from the dental chair to the floor. However, all types of dental chairs are not stable for MCC. We previously developed a procedure to stabilize a dental chair by using a stool. EUROPEAN RESUSCITATION COUNCIL (ERC) guideline 2015 adopted our procedure when cardiac arrest during dental surgery. The objective of this study was to verify the efficacy of a stool as a stabilizer in different types of dental chairs. Methods Three health care providers participated in this study, and 8 kinds of dental chairs were examined. MCC were performed on a manikin that was laid on the backrest of a dental chair. A stool was placed under the backrest to stabilize the dental chair. The vertical displacement of the backrest by MCC was recorded by a camcorder and measured by millimeter. Next, the vertical displacement of the backrest by MCC were compared between with and without a stool. Results In all 8 dental chairs, the method by using a stool significantly reduced the vertical displacements of the backrest by during MCC. The reduction ratio (mean [interquartile range]) varied between nearly 27 [20] and 87 [5] %. In the largest stabilization case, the displacement was 3.5 [0.5] mm with a stool versus 26 [5.5] mm without a stool (p