Shuichi Inaba

Relationship between the Ability to Detect Added Resistance at Rest and Breathlessness during Bronchoconstriction in Asthmatics

The ability to detect added resistance at rest was compared to the magnitude of breathlessness (evaluated by a modified Borg scale) during bronchoconstriction in 27 stable asthmatics. Threshold for resistive load detection was analyzed in terms of the Weber fraction (delta R/R0) and mouth pressure (P) at the threshold. Bronchoconstriction was induced by inhalation of aerosolized acetylcholine. Both delta R/R0 and P correlated inversely with the Borg score during bronchoconstriction (r = -0.537 and r = -0.689, respectively; p less than 0.01). On the other hand, during bronchoconstriction the Borg score did not correlate with increased lung volume, acute changes in arterial blood gas composition and drive and timing component of ventilation during bronchoconstriction, although bronchoconstriction caused significant changes in these variables. These results indicate that central processing of afferent stimuli rather than peripheral sensor contribute both to the ability to detect added resistance at rest and to the magnitude of breathlessness during bronchoconstriction in asthmatics.

Review of Spontaneous Pneumothorax Cases in Eastern Hokkaido.

昭和63年より平成5年まで当科で経験した自然気胸50例について検討した。内訳は男性43例, 女性7例である。そのうち11例22%は安静療法のみで気胸は改善し, 残り39例に対しては胸腔ドレナージを行い, 最終的に30例60%に気胸の改善をみた。しかし残り9例18%の症例は, 手術を必要とした。再発率は初回例39%, 2回目36%であり, 良性疾患で, 内科的治療の再発率は高いが半数以上は再発しない点を治療選択の際どう評価するかが, 意見の分かれるところと考える。さらにこれらの症例を対象に, 特発性自然気胸例における体格と胸部X線写真上で測定される肺の大きさとの関連を検討する目的で, 特発性気胸患者のうち10歳代から30歳代の男性気胸例34例を選択し, 年齢を合致させた男性対照30例についても比較検討した。身長については特発性気胸例については対照より有意に高値を呈し, 体重については低い傾向を示した。また肺の高さについては気胸群は対照群に比し有意に高値を呈し, 従来から言われている長身, 痩せ型の体型で, 肺の高さも高いことが裏づけられた。

Effects of Differences of Oxygen Affinity on Circulatory Response to Hypoxia

It is well known that tissue hypoxia is an important prognostic predictor in patients with chronic obstructive pulmonary disease (COPD). Compensatory responses to acute hypoxia occur in various organs and the magnitude of such response may also be an important factor in prognosis. P50, (oxygen tension at which the hemoglobin is 50% saturated with oxygen) is recognized as one of the factors affecting oxygen supply to the tissue. These studies were made to determine whether differences of P50 affect the circulatory response to acute hypoxia. Studies were made on nineteen male patients with COPD. They were divided into two groups according to low (less than 26.6 torr) or high (greater than 26.6 torr) P50. Isocapnic hypoxia was induced progressively with the patients being under right cardiac catheterization. The low P50 (25.8 +/- SD 0.6 torr) group included ten patients, and the high P50 (27.4 +/- 0.6 torr) group included nine patients. No differences could be detected in respect of pH, PaCO2, PaO2 or any hemodynamic parameters. Heart rate increased in both low and high P50 groups but the degree of the increase (delta HR/HR ROOM AIR x 100) in the high P50 group (20.7 +/- 9.2%) was significantly greater than in the low P50 group (9.4 +/- 10.9%). An increase in cardiac output was observed in the high P50 group (4.4 +/- 0.8 to 5.3 +/- 0.6 1/min), but not in the low P50 group (4.5 +/- 1.0 to 5.0 +/- 0.9 1/min). There was a significant positive relationship (r = 0.903) between hypoxic circulatory response and oxygen transport (TO2).(ABSTRACT TRUNCATED AT 250 WORDS)

Familial factors of airway reactivity and serum IgE levels in bronchial asthma

気管支喘息患者35例,家族に気管支喘息あるいはアレルギー性疾患を有しない健常人9例および気管支喘息患者の兄弟姉妹17例について,気道過敏性検査あるいは血清IgEレベルを検討した.その結果,喘息患者の兄弟姉妹の3例に血清IgEの高値が認められ,全てアトピー性喘息患者の兄弟姉妹であった.気道過敏性は健常人では認められなかつたが,喘息患者の兄弟姉妹の5例に軽度認められ, 1例がアトピー性喘息患者の兄弟姉妹で, 4例が非アトピー性喘息患者の兄弟姉妹例であった.以上の成績から,喘息患者の気道過敏性の亢進には,家族性因子が存在することが示唆された.