Temperature management for deliberate mild hypothermia during neurosurgical procedures

Deliberate mild hypothermia is safer from the point of view of adverse events and does not require a specific technique, unlike deep or moderate hypothermia. Therefore, mild hypothermia was widely used for neurosurgical procedures. Unfortunately, the neuroprotective efficacy of intraoperative mild hypothermia has not yet been proven; however, temperature management for intraoperative deliberate mild hypothermia has been improved over the past two decades. It is very important to achieve mild hypothermia before the commencement of the main surgery, and to maintain the patient's body temperature until the procedure is completed. In addition, it is also important to complete rewarming by the end of the surgery so that an accurate neurological evaluation can be made. Regarding the effects of mild hypothermia on outcomes, a large randomized controlled study reported that unfavorable outcomes did not differ between participants with or without hypothermia. Apart from these unfavorable outcomes, it is known that temperature management during deliberate intraoperative mild hypothermia has contributed to improvement of anesthesia practice. The accumulation of experience in this field is important. Clinical interest in deliberate mild hypothermia is currently low; however, anesthesiologists should be prepared for the time when it is required again in the future

持続的腎代替療法におけるメシル酸ナファモスタットの血中動態

Continuous renal replacement therapy (CRRT) is the preferred dialysis modality in critical care settings for patients with hemodynamic instability. Nafamostat mesylate (NM) is an anticoagulant commonly used (mainly in Japan) during CRRT in patients with high bleeding risk. In this study, we evaluated the pharmacokinetics of NM during CRRT. Patients undergoing CRRT therapy and using NM as the anticoagulant in the intensive care unit were enrolled in the study. Blood was collected from the CRRT circuit just after blood removal, just before and after the membrane for CRRT, and from the filtrates after the membrane. NM concentrations were measured using high-performance liquid chromatography. NM was detected in the intracorporeal circulation during CRRT in some cases, and liver enzymes were severely elevated in almost all of the cases. Coagulation time was prolonged even before the initiation of NM administration in these cases and may be associated with liver damage. This study suggests that NM dosage should take into account liver damage assessed by elevated liver enzymes.博士（医学）・乙第1531号・令和5年3月15

傾向スコアマッチング解析を用いた、全身麻酔術後の気管抜管後に発生する呼吸数変化を伴わない動脈血酸素飽和度低下の影響

BACKGROUND: It has been suggested that oxygen desaturation may be paradoxically related to the absence of an abnormal respiratory rate (RR) during acoustic respiratory rate (RRa) monitoring in a postoperative setting. We retrospectively compared the incidence of desaruration in patients without an abnormal RR with that in patients with an abnormal RR using propensity scorer matching. We also explored the factors contributing to oxygen desaturation without an RR monitoring alert. METHODS: We used ≤ 8 h postoperative data of the first 935 patients. Outcomes of patients with and without critical RR changes (RR > 30 or 2 min) (critical RR change vs. noncritical RR change) were first compared according to oxygen desaturation levels (SpO₂ 10 s). Multivariate analysis was used to determine oxygen desaturation-associated explanatory factors. RESULTS: Propensity score matching yielded 259 patients without critical RR changes and 259 patients with critical RR changes, respectively. Oxygen desaturation rates were higher in patients without critical RR changes [noncritical RR change vs. critical RR change: 39/220 (15.1%) vs. 16/243 (6.2%)]. An odds ratio and 95% CI for the noncritical RR change was 2.56 (1.38-4.55, P = 0.002). A critical change in the RRa was not observed in 576 patients; of these, oxygen desaturation was observed in 76 (13.2%) patients. Surgery duration (OR, 1.018 per 10 min increase; 95% CI, 1.002 to 1.035) was independently associated with oxygen desaturation without critical RR change. CONCLUSION: Postoperative oxygen desaturation paradoxically occurred more frequently in patients without critical RR changes, whose RR was monitored by the RRa under oxygen therapy. The duration of surgery may explain the possibility of postoperative oxygen desaturation without an RRa device alert.博士（医学）・甲第679号・平成30年3月15日Copyright © 2017 by authors and Via Medica This work is licensed under the Creative Commons Attribution International License (CC BY-NC-ND 4.0). https://creativecommons.org/licenses/by-nc-nd/4.0/The definitive version is available at " http://dx.doi.org/10.5603/AIT.a2017.0038

音響効果と超音波を用いた全身麻酔前後における気道径の比較

Changes in airway dimensions can occur during general anaesthesia and surgery for a variety of reasons. This study explored factors associated with postoperative changes in airway dimensions. Patient airway volume was measured by acoustic reflectometory and neck muscle diameter by ultrasound echography in the pre- and post-anaesthetic periods in a total of 281 patients. Neck circumference was also assessed during these periods. A significant decrease in median (IQR [range]) total airway volume (from 63.8 (51.8–75.7 [14.7–103]) ml to 45.9 (33.5–57.2 [6.4–96.3]) ml, p < 0.0001), and a significant increase in muscle diameter (from 4.3 (3.3–5.6 [2.2–9.0]) mm to 5.8 (4.7–7.3 [2.8–1.3]) mm, p < 0.0001) and neck circumference (from 34.0 (32.5–37.0 [29.5–49.0]) cm to 35.0 (33.5–38.0 [30.5–50.5]) cm, p < 0.0001) were observed. It may be possible that changes in airway volume and neck circumference were influenced by surgical duration or peri-operative fluid management (ρ) = −0.31 (95% CI −0.24 to −0.01), p = 0.0301, −0.17 (−0.23 to −0.06), p = 0.0038, 0.23 (0.12–0.34), p < 0.0001, and 0.16 (0.05–0.27), p = 0.0062, respectively). The intra-oral space can significantly decrease and neck thickness increase after general anaesthesia, and might increase the risk of difficult laryngoscopy and intubation if airway management is required after extubation following general anaesthesia.博士（医学）・甲第626号・平成27年3月16日Copyright © 1999-2015 John Wiley & Sons, Inc. All Rights Reserved.© 2014 The Association of Anaesthetists of Great Britain and Irelan

ヘモグロビン小胞体は無呼吸ラットにおいて循環虚脱までの時間を延長させる

BACKGROUND: Hemoglobin vesicles (HbV) are hemoglobin-based oxygen carriers manufactured by liposome encapsulation of hemoglobin molecules. We hypothesised that the infusion of oxygenated HbV could prolong the time to circulatory collapse during apnea in rats. METHODS: Twenty-four Sprague-Dawley rats were randomly divided into four groups (Air, Oxy, NS and HbV). The rats were anaesthetized with isoflurane and the trachea was intubated using 14-gauge intravenous catheters. Rats in the Air group were mechanically ventilated with 1.5% isoflurane in room air, and those in other groups received 1.5% isoflurane in 100% oxygen. Mechanical ventilation was withdrawn 1 min after the administration of rocuronium bromide to induce apnea. After 30 s, 6 mL saline and HbV boluses were infused at a rate of 0.1 mL/s in the NS and HbV groups, respectively. Circulatory collapse was defined as a pulse pressure < 20 mmHg and the time to reach this point (PP20) was compared between the groups. The results were analysed via a one-way analysis of variance and post-hoc Holm-Sidak test. RESULTS: PP20 times were 30.4 ± 4.2 s, 67.5 ± 9.7 s, 95 ± 17.3 s and 135 ± 38.2 s for the Air (ventilated in room air with no fluid bolus), Oxy (ventilated with 100% oxygen with no fluid bolus), NS (ventilated with 100% oxygen with a normal saline bolus), and HbV (ventilated in 100% oxygen with an HbV bolus) groups, respectively, and differed significantly between the four groups (P = 0.0001). The PP20 times in the HbV group were significantly greater than in the Air (P = 0.0001), Oxy (P = 0.007) and NS (P = 0.04) groups. CONCLUSION: Infusion of oxygenated HbV prolongs the time to circulatory collapse during apnea in rats.博士（医学）・甲第680号・平成30年3月15日© The Author(s). 2017 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated

橈骨遠位端骨折の外科的治療に対する、腕神経叢ブロック（腋窩アプローチ）と全身麻酔との間の患者満足度の比較

Background: Distal radius fracture surgery is performed under general (GA) or regional anesthesia with brachial plexus block (NB). Whether anesthesia type affects patient outcomes is unclear. This study retrospectively compared patient satisfaction between GA and NB after surgery. Methods: This was a historical cohort study of 80 (34 GA and 46 NB) patients who underwent volar plate fixation of distal radius fractures. Propensity score analysis was used to generate a set of matched cases (NB) and controls (GA), yielding 14 matched patient-pairs. The simplified patient satisfaction scale was compared for primary outcomes. Secondary outcomes were anesthesia and surgery duration, hospital stay length, adverse events, postoperative analgesic requirement, and wrist range of motion (ROM) 2 weeks and 3 months postoperatively. Results: After propensity score matching, patients in almost all cases in both groups were “Satisfied” (effect size: 0.1, p = 0.572), indicating little significant difference. Significant differences in adverse events and postoperative analgesic use observed before matching disappeared after matching. Anesthesia duration and hospital stay length were significantly shorter in the NB group (effect size: -1.27 and -0.77, p = 0.00074 and p = 0.0388, respectively), as was surgery duration (effect size: -0.84, p = 0.0122) after matching. Similar to before matching, wrist ROM significantly improved in the NB group (effect size: 1.11, p = 0.0279) in the early postoperative period, but the difference disappeared at 3 months postoperatively. Conclusions: Patient satisfaction between distal radius fracture surgery under GA and NB was similar. Nerve block could help shorten hospital stay length and surgery duration and improve postoperative functional recovery.博士（医学）・乙第1511号・令和3年6月25日Copyright © 2020 by author(s) and Scientific Research Publishing Inc. This work is licensed under the Creative Commons Attribution International License (CC BY 4.0). http://creativecommons.org/licenses/by/4.0

ALMA Measurement of 10 kpc-scale Lensing Power Spectra towards the Lensed Quasar MG J0414+0534

We report the first measurement of lensing power spectra for gravitational potential, astrometric shifts, and convergence perturbations towards the anomalous quadruply lensed quasar MG$\,$J0414+0534. To obtain the spectra, we conducted observations of MG$\,$J0414+0534 using the Atacama Large Millimeter/submillimeter Array (ALMA) with high angular resolution (0.02"-0.05"). We developed a new partially non-parametric method in which Fourier coefficients of potential perturbation are adjusted to minimise the difference between linear combinations of weighted mean de-lensed images. Using positions of radio jet components, extended dust emission on scales $>1\,$kpc, and mid-infrared flux ratios, which are microlensing free, our new multi-wavelength method provides us with a very effective tool for probing cosmological matter fluctuations on scales $< 10\,$kpc. Assuming that contributions from structures on angular scales <1.0" are negligible, on an angular scale of $\sim$1.3" (corresponding to an angular wave number of $l \sim 1.1\times 10^6$ or $\sim 8\,$kpc in the lens plane), the measured convergence, astrometric shift, and potential powers are $\varDelta_\kappa=0.021-0.028$, $\varDelta_\alpha =7-9\,$mas, and $\varDelta_\psi=1.2-1.6\,$$\textrm{mas}^2$, respectively. Our result is consistent with the predicted abundance of haloes in the line of sight and subhaloes in cold dark matter models. Our partially non-parametric lens models suggest a presence of a clump in the vicinity of object Y, a possible dusty dwarf galaxy and some small clumps in the vicinity of lensed quadruple images. Although much fainter than the previous report, we confirmed weak continuum emission from object Y with a peak flux of $\sim 100\,\mu \textrm{Jy}\, \textrm{beam} ^{-1}$ at the $\sim 4\,\sigma$ level.Comment: 29 pages, 35 figures, analyses of models with a possible dwarf galaxy, object Y and that of chi^2 fit in the visibility plane were adde

ウサギ脊髄虚血モデルにおけるミノサイクリンの神経保護作用の評価

OBJECTIVE: To investigate whether postischemic administration of minocycline attenuates hind-limb motor dysfunction and gray and white matter injuries after spinal cord ischemia. DESIGN: A prospective, randomized, laboratory investigation. SETTING: Laboratory in university, single institution. PARTICIPANTS: Male New Zealand White rabbits. INTERVENTION: Spinal cord ischemia was induced by an occlusion of the infrarenal aorta for 15 minutes. The groups were administered minocycline 1 hour after reperfusion (M-1; n = 8), minocycline 3 hours after reperfusion (M-3; n = 8), saline 1 hour after reperfusion (control [C]; n = 8), or saline and no occlusion (sham; n = 4). Minocycline was administered intravenously at 10 mg/kg 6 times at 12-hour intervals until 60 hours after the initial administration. MEASUREMENT AND MAIN RESULTS: Hind-limb motor function was assessed using the Tarlov score. For histologic assessments, gray and white matter injuries were evaluated 72 hours after reperfusion using the number of normal neurons and the percentage of areas of vacuolation, respectively. Motor function 72 hours after reperfusion was significantly better in group M-1 than in group C. The number of neurons in the anterior horn was significantly larger in group M-1 than in groups M-3 or C but did not differ significantly between groups M-3 and C. No significant difference was noted in the percentage of areas of vacuolation among the ischemia groups. CONCLUSIONS: Minocycline administration beginning at 1 hour after reperfusion improved hind-limb motor dysfunction and attenuated gray matter injury in a rabbit spinal cord ischemia model.博士（医学）・乙第1314号・平成25年5月29

Caution: Patient-specific preoperative preparations combined with procedure-specific 5-aminolevulinic acid may lead to critical events

5-Aminolevulinic acid (5-ALA) is orally administered 2-4 hours before surgery to identify tumor location. Hypotension is sometimes observed after 5-ALA administration. Case reoprtWe present a case of a patient with 5-ALA-induced hypotension that resulted in the development of cerebral infarction. An 83-year-old man with a bladder tumor was scheduled for photodynamic diagnosis-assisted transurethral resection of bladder tumor (PDD-TURBT) and right radical nephroureterectomy. 5-ALA was orally administered and his ordinary antihypertensive and antianginal agents were also administered an hour after 5-ALA administration. Following this, his blood pressure dropped, and he developed muscle weakness and paralysis in his left upper extremity. Magnetic resonance imaging showed evidence of cerebral infarction. ConclusionsWe cannot conclude definitively that our patient's cerebral infarction was solely caused by 5-ALA-induced hypotension because hypotension under these circumstances is not rare. We consider that additional factors, such as patient-specific doses of antihypertensive and antianginal agents may have played a role in the development of his cerebral infarction