Keyl C, Lemberger P, Rödig G, Dambacher M, Frey A
Institut für Anaesthesiologie, Universität Regensburg, Germany.
Br J Anaesth. 1994 Aug;73(2):157-61. doi: 10.1093/bja/73.2.157.
Using pulse oximetry and Holter ECG monitoring on the night before coronary bypass surgery, we studied 30 male patients with coronary artery disease to determine the relationship between nocturnal hypoxaemia and myocardial ischaemia. The patients received intensive anti-angina medication and were sedated with clorazepate. Ten patients developed a total of 42 ischaemic episodes, 24 of which occurred between 22:00 and 06:00. Mean heart rate was significantly higher in patients with ischaemia than in those without ischaemia. In 60% of all patients, heart rate increased > or = 20% at the onset of the ischaemic episode. The patients spent a median of 2 (range 0.02-40.6)% of the night with oxygen saturation (SpO2) < 90% (the minimum SpO2 value recorded was 84 (69-88) %). Only five ischaemic episodes were associated with respiratory events. These were not associated with either extraordinary oxygen desaturation or marked increases in heart rate. Comparing patients with and without ischaemia, there were no significant differences in the extent of nocturnal hypoxaemia or the pattern of desaturation episodes (cyclic variations in saturation characteristic of periodical breathing vs non-cyclic desaturation episodes). Despite marked nocturnal hypoxaemia, simultaneous occurrence of desaturation episodes and myocardial ischaemia was a rare event in our study.
在冠状动脉搭桥手术前一晚，我们对30名男性冠心病患者进行了脉搏血氧饱和度测定和动态心电图监测，以确定夜间低氧血症与心肌缺血之间的关系。患者接受强化抗心绞痛药物治疗，并用氯氮卓进行镇静。10名患者共发生42次缺血发作，其中24次发生在22:00至06:00之间。缺血患者的平均心率显著高于无缺血患者。在所有患者中，60%在缺血发作开始时心率增加≥20%。患者夜间氧饱和度（SpO2）<90%的时间中位数为2（范围0.02 - 40.6）%（记录的最低SpO2值为84（69 - 88）%）。只有5次缺血发作与呼吸事件相关。这些与异常的氧饱和度下降或心率显著增加均无关。比较有缺血和无缺血的患者，夜间低氧血症的程度或饱和度下降发作模式（周期性呼吸特征的饱和度周期性变化与非周期性饱和度下降发作）无显著差异。尽管夜间存在明显的低氧血症，但在我们的研究中，饱和度下降发作与心肌缺血同时发生是罕见事件。
