Department of Anesthesiology, Duesseldorf University Hospital, Duesseldorf, Germany.
Institute of Plant Biochemistry, Cluster of Excellence on Plant Sciences (CEPLAS), Heinrich-Heine-University Duesseldorf, Duesseldorf, Germany.
PLoS One. 2019 Dec 10;14(12):e0226146. doi: 10.1371/journal.pone.0226146. eCollection 2019.
Mild systemic hypothermia increases gastric mucosal oxygenation (μHbO2) during hemorrhagic shock in dogs. In the context of critical blood loss hypothermia might be fatal due to adverse side effects. Selective regional hypothermia might overcome these limitations. The aim of our study was to analyze the effects of regional gastric and oral mucosal hypothermia on μHbO2 and perfusion (μflow). In a cross-over study six anesthetized dogs were subjected to local oral and gastric mucosal hypothermia (34°C), or maintenance of local normothermia during normovolemia and hemorrhage (-20% blood volume). Macro- and microcirculatory variables were recorded continuously. During normovolemia, local hypothermia increased gastric microcirculatory flow (μflow) without affecting oxygenation (μHbO2) or oral microcirculation. During mild hemorrhagic shock gastric μHbO2 decreased from 72±2% to 38±3% in the normothermic group. This was attenuated by local hypothermia, where μHbO2 was reduced from 74±3% to 52±4%. Local perfusion, oral microcirculation and macrocirculatory variables were not affected. Selective local hypothermia improves gastric μHbO2 during hemorrhagic shock without relevant side effects. In contrast to systemic hypothermia, regional mucosal hypothermia did not affect perfusion and oxygen supply during hemorrhage. Thus, the increased μHbO2 during local hypothermia rather indicates reduced mucosal oxygen demand.
轻度全身低温可增加失血性休克犬胃黏膜的氧合（μHbO2）。在大量失血的情况下，低温可能因不良反应而致命。选择性区域低温可能克服这些限制。我们的研究目的是分析胃和口腔黏膜局部低温对μHbO2 和灌注（μflow）的影响。在一项交叉研究中，六只麻醉犬接受局部口腔和胃黏膜低温（34°C），或在正常血容量和出血（-20%血容量）期间维持局部正常体温。连续记录宏观和微循环变量。在正常血容量下，局部低温增加胃微循环流量（μflow），而不影响氧合（μHbO2）或口腔微循环。在轻度失血性休克期间，正常体温组胃黏膜的 μHbO2 从 72±2%降至 38±3%。局部低温可减轻这种降低，μHbO2 从 74±3%降至 52±4%。局部灌注、口腔微循环和宏观循环变量不受影响。选择性局部低温可改善失血性休克期间胃黏膜的 μHbO2，而无明显不良反应。与全身低温相比，区域黏膜低温在出血期间不影响灌注和氧供应。因此，局部低温期间 μHbO2 的增加表明黏膜氧需求减少。
