Alternations in Circadian Variation in Heart Rate Variability in Patients after Cervical Spinal Injury.

引言：众所周知，颈脊髓损伤患者会因损伤而导致自主神经系统（ANS）衰竭。手术刺激可触发病变水平以下的交感神经和副交感神经传入，这些传入不受脊髓上中枢的抑制。这可能导致手术后ANS活动恶化。方法：对12例ASAPS 1级或2级的脊柱手术患者，经医院批准和知情同意后，进行了ANS活动的测定。对6例颈椎病和6例后纵韧带损伤患者行颈椎固定减压术。使用活性示踪剂（AC 300，Suwa Trust，Tokyo）对每位患者进行24小时EEG记录。在术前2天（PRE）和术后进行测量 关于我们 再灌注-1（POD 1）、3（POD 3）、7（POD 7）天。用最大熵方法（Memcalc系统，Suwa Trust，Tokyo）计算功率谱。将心率变异性功率谱分为高频成分（HF：0.15 -0.40 Hz）、低频成分（LF：0.04-0.15 Hz）和比值（HF/LF）两个不同频段。HF用于反映迷走神经药物活性，LF用于反映交感神经和副交感神经的影响。计算LF/HF比值以反映交感迷走神经平衡。在基线（PRE）、POD 1、POD 3和POD 7的24小时内以及日间（8：00-21：00）和夜间（21：00-8：00）分析变量。用重复测量单因素ANOVA分析与基线值的差异，并认为p < 0.05的值具有显著性。结果：与术前相比，术后1天夜间、白天和24小时LF和HF均升高。在POD 3和POD 7下降。手术前心率变异性的昼夜变化减少手术后一周内恢复。结论：这些数据表明，手术操作和全身麻醉改变了颈髓损伤患者的交感神经和副交感神经功能。我们发现，通过比较白天和夜间的心率变异性变量，患者表现出在手术后一周内的昼夜节律城市的模式的改变。手术和麻醉引起的ANS活动和HRV昼夜变化的作用尚不清楚，需要在颈髓损伤患者中进行进一步研究。少

Introduction : Cervical spinal cord injury patients are known to suffer from the autonomic nervous system (ANS) failure as a result of their injury. Surgical stimulation may trigger sympathetic and parasympathetic afferents below the level of the lesion that are not inhibited by supraspinal centers. This can lead to deteriorate the ANS activity after the surgery. Analysis of the heart rate variability (HRV) can assess the changes in the ANS activity.This study was performed to evaluate the ANS activity after the spinal surgery under the general anesthesia.Method : After institutional approval and informed consent, 12 patients (ASAPS 1 or 2) were evaluated. Cervical fixation and decompression was carried out for six patients with cervical spondylosis and six patient with the posterior longitudinal ligament. Twenty-four hour EEG recordings were obtained for each patients with a active tracer (AC300, Suwa Trust, Tokyo). Measurements were performed on 2 day before surgery (PRE) and postope … More rative -1 (POD1), 3 (POD3), 7 (POD7) days. Power spectra were calculated with a maximum entropy method (Memcalc system, Suwa Trust, Tokyo). The power spectrum of HRV was divided into two different frequency bands : high-frequency component (HF:0.l5-0.40 Hz), low-frequency component (LF:0.04-0.15 Hz), and the ratio(HF/LF). The HF was used to reflect the vagally medicated activity and the LF to reflect both sympathetic and parasympathetic influences. The LF/HF ratio was calculated in order to mirror the sympathovagal balance. The variables were analyzed in 24-hours periods and also in daytime (8:00-21:00) and night-time (21:00-8:00) at baseline (PRE), POD1, POD3, and POD7. Difference from the baseline value were analyzed with repeated measure one-way ANOVA and significance was considered for values of p < 0.05. All data were expressed as mean ± SD.Result : LF and HF in night-time, daytime and 24-hours increased at POD1 as compared to PRE. They decreased at POD3 and POD7. The diminished circadian variation in HRV before surgery recovered within a week after the surgery.Conclusion : These data demonstrate that surgical procedure and general anesthesia altered the sympathetic and parasympathtic function in patients with cervical spinal cord injury. We found by comparing daytime and night-time HRV variables, that patients demonstrated alterations in a pattern of circadian rhythm city within a week after the surgery. The role of the changes in the ANS activity and circadian variations of HRV induced by the surgical procedure and anesthesia is still unclear and further studies will be needed in patients with cervical spinal cord injury. Less