稲桝 丈司

BACKGROUND: For cardiac arrest (CA) victims, brain computed tomography (CT) may serve as a prognosticator. Loss of gray-white matter discrimination (GWMD) and sulcal edema/effacement are reliable CT signs of hypoxia, and a time window may exist for development of these signs. Most data are derived from CA victims of cardiac etiology, however, and CT signs have rarely been evaluated in victims of CA secondary to subarachnoid hemorrhage (SAH). METHODS: A retrospective study was conducted to clarify the incidence, temporal profile, and prognostic significance of early CT signs in resuscitated SAH-CA patients. RESULTS: During a 6-year period, 35 SAH-CA patients were identified. CT signs were observed in 94 %: loss of GWMD was observed in 94 %, whereas sulcal edema/effacement was observed in 77 %. In 29 patients, the interval between CA and the return of spontaneous circulation (ROSC) was estimated. CT signs developed almost invariably when the CA-ROSC interval exceeded 10 min. Loss of GWMD always preceded sulcal edema/effacement. None of the 35 patients achieved long-term survival, regardless of the presence of the CT signs. CONCLUSION: CT signs may develop earlier in patients with SAH-CA than CA of cardiac origin. Because of a poor prognosis, early CT signs are not useful prognosticators in that population.

A case of reversible pontine ischemia following diagnostic cerebral angiography performed to evaluate vertebral artery dissection (VAD) of ischemic onset is reported. A 40-year-old man presented with sudden neck pain, dizziness, difficulty in swallowing, and numbness in the left arm. Neurologically, his symptoms were compatible with incomplete Wallenberg syndrome. Diffusion-weighted magnetic resonance imaging (DWI) revealed a small infarction in the medulla oblongata, and the right VA was irregularly stenotic on magnetic resonance angiography (MRA). We suspected that the right VAD was the cause of the medullary infarction. Following conservative treatment, his deficits resolved quickly despite progression of the VAD as revealed by follow-up MRA. Subsequently, diagnostic cerebral angiography was performed with the purpose of evaluating the patency of the right VA and possibility of a dissecting aneurysm. Despite a seemingly uneventful procedure, however, the patient developed altered mental status and right-sided hemiparesis shortly after the placement of an angiographic catheter into the intact left VA. DWI obtained two hours after the procedure revealed a high-intensity signal in the paramedian pons. Following administration of IV heparin and edaravone, the neurological deficits as well as the high-intensity signal disappeared within 24 h. The patient was discharged without deficits 4 weeks after onset. Although cerebral angiography has been considered the gold standard for the diagnosis of VAD, its role in VAD of ischemic onset has recently been questioned, in light of its relatively benign natural history, improved quality of less invasive imaging modalities, and risks of cerebral angiography. From the perspective of avoiding complications, the common practice of obtaining diagnostic cerebral angiography from every patient with VAD of ischemic onset may have to be reviewed, and decision to perform cerebral angiography for those who have already been diagnosed with less invasive imaging modalities should be made cautiously and on case-by-case basis.

目的：近年，法医学の分野で，死後に血清のケトン体を測定することが，死因の推定において有用であるとする報告がある。我々は当院救命救急センターに搬送された院外心肺停止症例に対し，血清ケトン体である3-ヒドロキシ酪酸（3-hydroxybutyrate; 3-HB）を測定し検討した。対象と方法：2008年1月から2008年4月までの間に当施設に搬送された院外心肺停止症例125例（外傷による心肺停止例，小児例は除く）のうち，3-HBを測定し得た69例を対象とした。69例は3-HB値に基づき4群に分類した。3-HB値が1,000 μmol/l以上をA群，200～1,000 μmol/lをB群，50～200 μmol/lをC群，50 μmol/l以下をD群とした。3-HB値を測定し得た症例の診療録をもとに病歴・身体所見・血液検査所見・画像所見からケトン体の上昇を来す病態（飢餓・高血糖・感染）を有する症例を抽出した。69例のうち自殺・明らかな窒息・溺水の11例を除く内因性の院外心肺停止症例58例について，病悩期間なく突然に心肺停止に至ったものをaccidental episodes群（AE群32例），病悩期間を経て心肺停止に至ったものを非AE群26例とした。両群間の3-HB値を検討し，Mann-Whitney's U testを用いて有意差検定を行い，p<0.05を有意差ありとした。結果：69例の内訳は，男性37例，女性32例，年齢は16歳から92歳（中央値75歳）であった。69例のうち19例にケトン体の上昇を来す病態である飢餓・高血糖・感染を認めた。ケトン体の上昇を来すとされる要因が，それぞれA群で100%（5例），B群で86%（6例），C群で22%（6例），D群で7%（2例）に認められた。またAE群，非AE群間の比較では，非AE群において有意に3-HB値が高値であった。結語：心肺停止患者の3-HB値が高値である場合には，心肺停止に先立ちケトン体の上昇を来す病態が存在した可能性が高い。