【原】【省立疼痛英语晨读】脊髓电刺激程控：速成课程（十）

 英语晨读 ·

山东省立医院疼痛科英语晨读已经坚持10余年的时间了，每天交班前15分钟都会精选一篇英文文献进行阅读和翻译。一是可以保持工作后的英语阅读习惯，二是可以学习前沿的疼痛相关知识。我们会将晨读内容与大家分享，助力疼痛学习。

本次文献选自Sheldon B , Staudt M D , Williams L , et al. Spinal cord stimulation programming: a crash course[J]. Neurosurgical Review, 2020:1-12.

Paresthesia vs. paresthesia-free

Paresthesias are the “tingling” sensations that are designed to overlap a patient’s somatotopic pain distribution, thereby altering the normal sensory pathways and masking the pain. Tonic SCS utilizes low-frequency stimulation between 40 and 100 Hz to produce paresthesias, and it has been theorized that tonic stimulation modulates the lateral discriminatory pathway of pain generation [42]. Although stimulation-induced paresthesias are typically described as pleasant sensations, some patients may find them uncomfortable. When performing programming to improve pain coverage or stimulation intensity, is important to understand how much paresthesia a patient can withstand.

感觉异常VS无感觉异常

感觉异常是一种针刺的感觉，来覆盖人体疼痛区域，从而改变正常感觉传导，覆盖疼痛。紧张性刺激利用频率在40-100Hz之间的低频刺激产生感觉异常，理论上来讲，紧张性刺激可以调控疼痛产生外侧传导通路。虽然刺激产生的异感通常描述为愉快的感觉，但是患者可能会感觉到不舒服。当调节程序改变疼痛覆盖范围及刺激强度时，确认患者能忍受的感觉异常是很重要的。

Despite high-quality evidence demonstrating pain relief from tonic SCS [43, 44], there remained a significant amount of patients who did not respond, including patients with predominant axial back pain. So-called “subthreshold” or paresthesia-free stimulation programs have been created where minimal to no paresthesias are felt, with trials demonstrating efficacy in patients with axial back pain [45]. Two such paresthesia-free settings include high-frequency stimulation (HFS) and burst waveform SCS. A schematic representation of different waveforms is depicted in Fig. 4. When implanting a device, it is important to understand the combinations of stimulation (i.e., HFS, burst, and/or tonic) permitted since they vary depending on the device chosen.

尽管高质量的证据表明紧张性SCS可以缓解疼痛[43,44]，但仍有相当数量的患者对此没有反应，包括主要的中轴性背痛患者。已经生产出亚阈值或无异感刺激系统，其中异感最小到感觉不到，试验证明对中轴性背痛[45]患者有效。两种无异感的设备包括高频刺激(HFS)和脉冲波形SCS。图4描述了不同波形的示意图。在植入设备时，了解允许的刺激组合(即HFS、burst和/或强直刺激)是很重要的，因为它们随设备的选择而不同。

HFS is defined as > 500 Hz by some and greater than 10,000 Hz by others. Stimulation at 10,000 Hz has been found to alleviate chronic back and leg pain more effectively than tonic SCS in a prospective randomized control trial (SENZA) [46]; however, it also had a significant adverse impact on battery life. Burst stimulation is a subthreshold waveform which has been hypothesized to mimic the innate firing of the nervous system and is highly efficient with regard to battery life. It consists of a series of pulses of increasing amplitude (called a “packet”) followed by a brief quiescent period, after which the pattern repeats [47]. Compared to tonic SCS, burst SCS has been demonstrated to confer superior pain control in patients with FBSS [48], and also has the capability of rescuing non-responders to tonic SCS [49]. The recent prospective randomized control of tonic vs burst SCS (SUNBURST) demonstrated superiority of burst stimulation for chronic trunk and/or extremity pain [50].

一些人定义HFS为> 500 Hz，而另一些人则定义为大于10,000 Hz。在一项前瞻性随机对照试验(SENZA)[46]中，发现10000赫兹的刺激比紧张性SCS更能有效缓解慢性背部和腿部疼痛;然而，它也对电池寿命产生了重大的不利影响。脉冲刺激是一种亚阈值波形，假设来模拟神经系统的先天放电，并且在电池寿命方面是非常有效的。它由一系列振幅增加的脉冲(称为“包”)和短暂的静止期组成，之后模式重复[47]。与紧张性SCS相比，脉冲性SCS已被证明在FBSS[48]患者中具有更强的疼痛控制能力，并有能力挽救对紧张性SCS[49]无反应的患者。近期的前瞻性随机对照研究表明，脉冲SCS (SUNBURST)刺激与常规刺激相比对慢性躯干和/或肢体疼痛具有优越性。

When initially establishing a therapeutic burst program, the amplitude is set at half the threshold calculated at the initial programming visit. The burst cycle is a continuous pattern between when stimulation is on and off. Typically, the cycle is 30 to 90 s on and 6 min off, which allows for more efficient energy expenditure. Running a continuous burst cycle is possible, but results in higher energy expenditure and is often uncomfortable for the patient. A starting burst program may have pulses set for 30 s at 40 Hz, individual pulses at 500 Hz, with pulse width maxed out at 1000 μs [47]. This packet would then be followed by the quiescent period for 3 min. As mentioned, the patient should not feel any stimulation during burst programming. As long as pain relief can be maintained, a programmer may opt to increase the quiescent period up to 6 min to further conserve IPG battery life.

当最初建立一个治疗性脉冲方案时，振幅设定为在最初程序设计时计算的阈值的一半。脉冲周期是在刺激开关之间一个连续的模式。通常，周期是30到90秒，关闭6分钟，这允许更有效的能源消耗。运行连续的脉冲周期是可能的，但导致更高的能量消耗，并且患者经常不舒服。起始脉冲程序可设置为将脉冲30秒，频率40 Hz，单个脉冲设置为500 Hz，脉冲宽度最大设置为1000 μs[47]。脉冲之后是3分钟的静止期。如前所述，在脉冲编程过程中，患者不应该感到任何刺激。只要疼痛缓解可以维持，程序员可以选择增加静止时间高达6分钟，以进一步保存IPG电池寿命。