自発的な脱水と,システィック線維症における熱不耐性
O Bar-Or1, C J Blimkie, J A Hay
1Children's Exercise and Nutrition Centre, Department of Pediatrics, Hamilton, Ontario, Canada.
Lancet (London, England)
|March 21, 1992
まとめ
結晶性線維症 (CF) の子どもは,暑さでの運動中に,自分の水分需要を過小評価することがあります. これは,渇き反応の減少による過度の脱水につながり,健康上のリスクを高めます.
科学分野:
- 運動生理学 運動生理学
- 小児科は小児科です.
- 肺内医学 肺内医学 肺内医学
背景:
- 運動はシスティック線維症 (CF) 患者にとって有益ですが,熱ストレスは罹病率と死亡率を増加させます.
- CFの患者は,汗塩の含有量が高く,長時間汗をかいたときに渇望の調節を潜在的に変化させる可能性があります.
研究 の 目的:
- 熱い環境での運動中にCFを患っている子供たちが渇き反応が低下しているかどうかを調査する.
- 喉の渇きによる水分補給を受けた対照群と比較して,CF患者の液体摂取量と脱水レベルを評価する.
主な方法:
- CFを患った8人の子供と8人の対照群は,制御された熱い環境 (31-33°C) で2回の運動会を行いました.
- 水分補給は,渇きによって導かれ,またはランダムな順番で制御 (強制飲酒) された.
- 流体摂取量,体重の変化,心拍数回復をモニターした.
主要な成果:
- CFの患者は,渇きを誘導した状態で,対照群 (1.73%および0.78%) よりも著しく少ない量 (0.80%の体重) を飲み,より多くの液体 (1.57%の体重) を失いました.
- 心拍の回復が遅いのがCF患者で観察されましたが,他の熱ストレスの徴候は異なっていません.
- 強制飲酒のセッションでは,グループ間の違いは見つかりませんでした.
結論:
- CFの子供は,暑い環境での運動中に水分補給の必要性を著しく過小評価します.
- この渇き感の障害は,過度の脱水につながり,潜在的健康リスクをもたらします.
- 喉の渇きによる水分補給は,熱の中で運動するCF患者には不十分です.
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