术后急性疼痛与慢性疼痛关系的研究进展

背景 术后急性疼痛管理仍然不尽人意,如何防治急性疼痛转化为慢性疼痛仍然是临床亟待解决的问题. 目的 阐述术后急性疼痛转化为慢性疼痛的研究进展,为术后疼痛管理以减少慢性疼痛的发生提供参考. 内容 就急性疼痛转化为慢性疼痛的可能性等方面作一综述. 趋向 进一步研究术后急性疼痛转化为慢性疼痛的机制,以明确有效的预防急性疼痛慢性化的方法.     

Effects of noxious stimulation and pain expectations on neuromuscular control of the spine in patients with chronic low back pain

Background context

Alterations of the neuromuscular control of the lumbar spine have been reported in patients with chronic low back pain (LBP). During trunk flexion and extension tasks, the reduced myoelectric activity of the low back extensor musculature observed during full trunk flexion is typically absent in patients with chronic LBP.

Purpose

To determine whether pain expectations could modulate neuromuscular responses to experimental LBP to a higher extent in patients with chronic LBP compared with controls.

Study design

A cross-sectional, case-control study.

Patient sample

Twenty-two patients with nonspecific chronic LBP and 22 age- and sex-matched control participants.

Methods

Trunk flexion-extension tasks were performed under three experimental conditions: innocuous heat, noxious stimulation with low pain expectation, and noxious stimulation with high pain expectation. Noxious stimulations were delivered using a contact heat thermode applied on the skin of the lumbar region (L4–L5), whereas low or high pain expectations were induced by verbal and visual instructions.

Outcome measures

Surface electromyography of erector spinae at L2–L3 and L4–L5, as well as lumbopelvic kinematic variables were collected during the tasks. Pain was evaluated using a numerical rating scale. Pain catastrophizing, disability, anxiety, and fear-avoidance beliefs were measured using validated questionnaires.

Results

Two-way mixed analysis of variance revealed that pain was significantly different among the three experimental conditions (F2,84=317.5; p<.001). Increased myoelectric activity of the low back extensor musculature during full trunk flexion was observed in the high compared with low pain expectations condition at the L2–L3 level (F2,84=9.5; p<.001) and at the L4–L5 level (F2,84=3.7; p=.030). At the L4–L5 level, this effect was significantly more pronounced for the control participants compared with patients with chronic LBP (F2,84=3.4; p=.045). Pearson correlation analysis revealed that increased lumbar muscle activity in full flexion induced by expectations was associated with higher pain catastrophizing in patients with chronic LBP (r=0.54; p=.012).

Conclusions

Repeated exposure to pain appears to generate rigid and less variable patterns of muscle activation in patients with chronic LBP, which attenuate their response to pain expectations. Patients with high levels of pain catastrophizing show higher myoelectric activity of lumbar muscles in full flexion and exhibit greater neuromechanical changes when expecting strong pain.     

Repositioning accuracy and movement parameters in low back pain subjects and healthy control subjects

Study Design: A control group study with repeated measures. Objective: To compare trunk repositioning parameters in chronic low back pain (LBP) and healthy subjects. Summary and background data: Recent evidence suggests that chronic LBP patients exhibit deficits in trunk proprioception and motor control. Trunk repositioning and the various spatio-temporal parameters related to it can be used to evaluate sensori-motor control and movement strategies. Methods: Fifteen control subjects and 16 chronic LBP subjects participated in this study. Subjects were required to reproduce different trunk position in flexion (15°, 30° and 60°) and extension (15°). In the learning phase preceding each condition, visual feedback was provided. Following these learning trials, subjects were asked to perform ten consecutive trials without any feedback. Movement time, movement time variability and peak velocity were obtained and a temporal symmetry ratio was calculated. Peak angular position variability and absolute error in peak angular position were also calculated to evaluate spatial accuracy. Results: Two subgroups of LBP patients were identified. One subgroup of LBP subjects demonstrated longer movement time and smaller peak velocities and symmetry ratios than normal subjects. No group difference was observed for peak angular position variability and absolute error in peak angular position. Conclusion: Chronic LBP patients, when given a sufficient learning period, were able to reproduce trunk position with a spatial accuracy similar to control subjects. Some LBP subjects, however, showed modifications of movement time, peak velocity and acceleration parameters. We propose that the presence of persistent chronic pain could induce an alteration or an adaptation in the motor responses of chronic LBP subjects.     

A prospective observational study to investigate the relationship between local anesthetic infiltration pain before spinal anesthesia and acute and chronic postsurgical pain in women undergoing elective cesarean delivery

BackgroundCesarean delivery is one of the most common procedures performed worldwide. We conducted this prospective cohort study to evaluate the association between local anesthetic infiltration (LAI) pain prior to spinal anesthesia and pain and morphine consumption within 24 h after cesarean delivery (primary outcomes). A secondary objective was to assess the association between LAI pain and pain at one month postoperatively.MethodsRecruitment of 216 eligible women scheduled for elective cesarean delivery. Local infiltration before spinal anesthesia was performed using a 24-gauge needle and 3 mL 2% plain lidocaine. All subjects received 2.2 mL 0.5% hyperbaric bupivacaine with 200 µg morphine for spinal anesthesia. A 0–10 verbal numerical rating scale was used to assess LAI pain severity, and subsequent pain at 24 h, 1, 3 and 12 months.ResultsWe found a moderate correlation between LAI pain intensity and severity of acute pain at rest (rho=0.56, P <0.001) and with movement (rho=0.58, P <0.001) and a weak correlation with morphine consumption (rho=0.17, P=0.01) within 24 h postoperatively. We also found a positive correlation between LAI pain and the severity of persistent wound pain at rest (rho=0.30, P <0.001) and with movement (rho=0.52, P <0.001) at 1 month. The incidence of wound pain at 1, 3 and 12 months postoperatively was 37.1%, 7.0% and 1.4%, respectively.ConclusionsPain from LAI prior to spinal anesthesia is significantly associated with subsequent postoperative pain both acutely and at one month in women scheduled for elective cesarean delivery under spinal anesthesia.     

The impact of aerobic fitness on functioning in chronic back pain

Despite lack of convincing evidence that reduced aerobic fitness is associated with chronic back pain (CBP), exercise programs are regarded as being effective for persons with non-specific CBP. It is unsure whether gain in aerobic fitness following intervention is associated with functioning improvement in persons with CBP. The objective of this prospective cohort study was to study the impact of aerobic fitness on functioning in persons with CBP, at baseline and following 3-week intensive interdisciplinary intervention. This study included persons who had passed 8 weeks of sick-listing because of back pain (n = 94) and were referred to a 3-week intensive biopsychosocial rehabilitation program. Aerobic fitness was assessed with a sub-maximal bicycle test at baseline, at admission to and discharge from the rehabilitation program, and at 6 months follow-up. Contextual factors, body function, activity and participation were evaluated before and after intervention. In addition, working ability was recorded at 3-years follow-up. At baseline aerobic fitness was reduced in most subjects, but improved significantly following intervention. Baseline measurements and intervention effects did not differ among the diagnostic sub-groups. Neither contextual factors nor functioning at baseline were associated with aerobic fitness. Increase in aerobic fitness was not associated with improvements in functioning and contextual factors and work-return following intervention either. From this study we conclude that improvement of aerobic fitness seems of limited value as goal of treatment outcome for patients with CBP.     

SMoC-Wrist: a sensorimotor control-based exercise program for patients with chronic wrist pain

Study designThis is a narrative review.IntroductionChronic wrist pain is a common disorder that can lead to considerable disability in performing activities in daily living and at work. Patients with nonspecific chronic wrist pain are regularly referred to a physiotherapist/hand therapist. Immobilization, avoiding excessive wrist load, steroid injections, and various physical therapy methods predominantly focus on the pain itself. However, these methods often do not result in a satisfactory long-term pain relief.Purpose of the studyIn this article, we will describe the principles behind and content of a sensorimotor control–based exercise program as introduced by Videler et al., modified and substantiated by current insights into sensorimotor control training and wrist kinetics.MethodsBoth structure and content of the modified exercise program (SMoC-wrist) are substantiated by recent scientific literature.ResultsA clear 4-level exercise model based on sensorimotor principles is presented, that is, proprioceptive level, conscious static/isometric level, conscious dynamic level, and unconscious dynamic level. The content of each level and the transition toward the next level are described in detail.DiscussionBesides the substantiation of the exercise program, possible outcome measures for joint position sense and kinesthesia of the wrist are discussed.ConclusionWe modified and substantiated a widely used exercise program for patients with nonspecific chronic wrist pain based on recent insights into sensorimotor control principles and wrist kinematics. The presented exercise program (SMoC-wrist) is not primarily focused on reducing pain but on functional reeducation and strengthening of the neuromusculoskeletal system on the basis of sensorimotor control principles.     

术前疼痛灾难化和全膝关节置换术后慢性疼痛的相关性

目的 探讨膝骨关节炎(KOA)患者术前疼痛灾难化与全膝关节置换术(TKA)术后慢性疼痛(CPSP)的相关性。方法 选择2020年8月至2021年1月行首次单侧TKA患者240例,男105例,女135例,年龄45～64岁,BMI 18～30 kg/m²,ASAⅠ—Ⅲ级。根据是否发生术前疼痛灾难化将患者分为两组：灾难化组(n=78)和非灾难化组(n=162)。所有患者麻醉方法和手术方式一致。记录性别、年龄、BMI、ASA分级、K-L分级、KOA病程、术前合并心血管疾病、术前镇痛药物使用例数和术前1 d C-反应蛋白(CRP)浓度。术前1 d记录医院焦虑抑郁量表(HAD)、中枢敏化问卷(CSQ)和疼痛灾难化量表(PCS),若PCS评分≥30分认为发生疼痛灾难化。记录术中丙泊酚、瑞芬太尼、舒芬太尼用量、出血量、止血带使用时间、手术时间、补救镇痛例数、术后住院时间和术后6个月内使用非甾体抗炎药(NSAIDs)例数。记录术后6个月静息和活动时VAS疼痛评分,若术后6个月静息或(和)活动时VAS疼痛评分>3分记为发生CPSP。采用Poisson回归分析评估发生术前疼痛灾难...     

The relationship between interstitial cystitis and endometriosis in patients with chronic pelvic pain.

OBJECTIVE: This study was designed to determine the relationship between interstitial cystitis (IC), endometriosis (endo), and chronic pelvic pain (CPP) in individuals in whom nongynecological and nonurological problems had been previously ruled out. METHODS: A prospective study of 162 consecutive women with a complaint of chronic pelvic pain seen in the clinic was performed between August 2002 and December 2005. These patients underwent a workup to exclude other causes of pelvic pain, had PUF (Pain Urgency and Frequency) questionnaires filled out, and underwent a laparoscopy and a cystoscopy with hydrodistention. Pain levels were determined, and treatment was reviewed and enumerated. Results were obtained and quantified. RESULTS: In this study, 123 (76%) patients were diagnosed with active endometriosis, 133 (82%) were diagnosed with interstitial cystitis, and 107 (66%) had both disease entities simultaneously. Thirteen (8%) patients were diagnosed with pathologies unrelated to endometriosis and interstitial cystitis. Pain levels were seen to decrease at 6 months in all groups of patients with the exception of those patients with endometriosis only. CONCLUSION: CPP is a difficult, taxing, and frustrating concern for many women in the United States. These individuals have traditionally been difficult to treat. A large number of women with CPP in our patient population have been shown to have endometriosis, interstitial cystitis, or both. Therefore, a workup for premenopausal individuals with CPP involves obtaining a history that keys into possible nongynecologic causes of pain, a complete accounting of urinary problems, and a thorough history of gynecological problems. A physical examination with a comprehensive history should be performed, and the investigation may include the possibility of a simultaneous laparoscopy and cystoscopy if warranted. These procedures can serve as both a means for diagnosis and treatment of these problems when encountered.     

Pathogenesis and mechanisms of pain in chronic pancreatitis

虽然慢性胰腺炎的病理已经十分清楚，但其早期的致病机制尚不明确。慢性胰腺炎的一般特点为纤维化，慢性炎症和胰腺实质的消失，这些特征会随着疾病的发展而逐渐出现，同时还伴有急性胰腺炎的症状。一些专家认为慢性胰腺炎继发于急性胰腺炎。另一些则认为慢性胰腺炎首先发生，急性胰腺炎则在此基础上发生。慢性胰腺炎所引起的疼痛可通过许多机制发生。增高的胰腺压力可干扰神经，影响血流，改变pH值，并引起有毒物质的潴留，激活动作电位。组织的破坏和炎症介质的释放可刺激传入神经。甚至，炎症可直接破坏神经，引起神经性疼痛。掌握疼痛在外周和中枢神经系统中的神经冲动传递路径才能找出减轻胰性疼痛的有效方法。疼痛可以通过内脏、迷走、脊神经和膈神经等外周神经传递。它也可通过脊髓的背侧神经束和脊髓丘脑束中继传递。因此寻找到新的治疗胰性疼痛的方法是可能的。     

Spontaneous movements, local reactions and pain on injection of rocuronium. A comparison between female and male patients

BACKGROUND: We investigated the incidence of withdrawal, local reactions and pain on injection of rocuronium in 120 adult ASA I-II patients undergoing general anaesthesia (group A: 60 male patients, group B: 60 female patients). METHODS: After induction of anaesthesia with propofol and remifentanil, rocuronium 0.6 mg kg(-1) was injected in a separate intravenous cannula on the opposite arm. The patient's response to the injection of rocuronium was graded using a four-point scale. The appearance of local signs (i.e. erythema, venous sequelae) on the arm where rocuronium had been injected was recorded at the end of the injection as well as 1 h and 24 h after recovery from anaesthesia. Moreover, patients were asked 24 h after recovery from anaesthesia whether they had recall of pain or movements in this arm during induction of anaesthesia. RESULTS: In 26 of the 120 patients (22%) included, withdrawal reactions after injection of rocuronium were observed. Of these 26 patients, 16 (13%) had severe movements. The overall incidence of withdrawal reactions after rocuronium as well as the incidence of severe reactions was significantly higher in female patients compared to male patients (overall incidence: 18 females (30%) vs. 8 males (13%), P<0.05; severe reaction: 13 females (22%) vs. 3 males (5%), P<0.05). No local reactions were observed and no patient remembered any pain or movements during induction of anaesthesia. CONCLUSION: The incidence and the degree of withdrawal reactions in response to the injection of rocuronium were significantly higher in women than in men. This was not associated with adverse clinical consequences for the patient's outcome.     

腹内高压与急性胰腺炎严重程度的相关性分析

目的：探讨腹内高压（IAH）与急性胰腺炎（AP）病情严重程度的相关性。 方法： 选取2014年2月—2015年2月收治的AP患者80例,根据入院APACHE II评分,其中轻症胰腺炎（MAP）49例（MAP组）,重症胰腺炎（SAP）31例（SAP组）。采用经膀胱间接测量法监测腹内压（IAP）,4 h/次,连续5 d,连续2次IAP值≥12 mmHg诊断为IAH。比较两组IAH发生率,分析IAP值与APACHE II评分的相关性;比较SAP患者中发生IAH与未发生IAH患者不良临床事件的发生率,采用ROC曲线（AUC）评价APACHE II评分和IAP值预测SAP患者不良临床事件的价值。 结果：SAP组IAH发生率明显高于MAP组（45.2% vs. 0%,P<0.05）;Pearson相关分析结果显示,IAP值与APACHE II评分呈正相关（r=0.752,P<0.05）;SAP患者中,发生IAH者各项不良临床事件发生率均明显高于未发生IAH者（P<0.05）;IAP值预测SAP患者不良临床事件的AUC明显大于APACHE II评分（0.892 vs. 0.610,P<0.05）。 结论：IAH与AP病情严重程度密切相关,并影响AP患者的临床结局。IAP在预测SAP患者不良临床事件发生风险的方面具有重要的临床价值。     

超前镇痛对开胸病人术后慢性疼痛影响的临床研究

目的探讨超前镇痛对开胸病人术后慢性疼痛的影响。方法72例ASAⅠ～Ⅱ级择期开胸手术病人,随机分为两组：术前及术后硬膜外腔罗哌卡因复合吗啡用药组（PE及E组）。记录术后4、8、16、24、30h和48h的疼痛评分,随访患者术后2个月、4个月慢性疼痛的持续情况。结果术后48h内各时间点,PE组与E组的疼痛评分无明显差异（P〉0.05）。PE组术后疼痛持续2个月、4个月的发生率较E组低（χ^2=5.989,P=0.014;χ^2=7.603,P=0.006）;PE组与E组相比,疼痛持续时间缩短（P=0.027）。结论超前镇痛能更有效地降低开胸术后病人慢性疼痛的程度和发生率。     

Acute to chronic postoperative pain in children: preliminary findings

Background/purpose

Chronic postoperative pain is a well-established clinical phenomenon that is associated with adverse outcomes. The incidence of this clinical phenomenon in children, however, is not well established. The purpose of this study was to identify the incidence of chronic pain in children after surgery.

Methods

Following a screening process, a total of 113 children and their parents were enrolled in this cross-sectional study. Data regarding persistence and characteristics of pain after surgery were obtained.

Results

Approximately 13% of the children, most of whom underwent orthopedic procedures, reported the existence of symptoms of chronic postoperative pain. Most of the children indicated that the pain started immediately after surgery, was localized to the surgery site, and was intermittent. Children reported a median duration of pain of 4.1 months, and approximately half of the children experienced pain most days of the week. Up to 30% of the children reported interference of pain in functioning in areas such as extracurricular activities and sleep.

Discussion

Given the large number of children at risk for experiencing chronic postoperative pain, preventative efforts are necessary. Large-scale cohort prospective studies are needed to confirm the results of this cross-sectional study.     

Spinal segmental stabilisation exercises for chronic low back pain: programme adherence and its influence on clinical outcome

Exercise rehabilitation is one of the few evidence-based treatments for chronic non-specific low back pain (cLBP), but individual success is notoriously variable and may depend on the patient’s adherence to the prescribed exercise regime. This prospective study examined factors associated with adherence and the relationship between adherence and outcome after a programme of physiotherapeutic spine stabilisation exercises. A total of 32/37 patients with cLBP completed the study (mean age, 44.0 (SD = 12.3) years; 11/32 (34%) male). Adherence to the 9-week programme was documented as: percent attendance at therapy, percent adherence to daily home exercises (patient diary) and percent commitment to rehabilitation (Sports Injury Rehabilitation Adherence Scale (SIRAS)). The average of these three measures formed a multidimensional adherence index (MAI). Psychological disturbance, fear-avoidance beliefs, catastrophising, exercise self-efficacy and health locus of control were measured by questionnaire; disability in everyday activities was scored with the Roland–Morris disability scale and back pain intensity with a 0–10 graphic rating scale. Overall, adherence to therapy was very good (average MAI score, 85%; median (IQR), 89 (15)%). The only psychological/beliefs variable showing a unique significant association with MAI was exercise self-efficacy (Rho = 0.36, P = 0.045). Pain intensity and self-rated disability decreased significantly after therapy (each P < 0.01). Adherence to home exercises showed a moderate, positive correlation with the reduction in average pain (Rho = 0.54, P = 0.003) and disability (Rho = 0.38, P = 0.036); higher MAI scores were associated with greater reductions in average pain (Rho = 0.48, P = 0.008) and a (n.s.) tendency for greater reductions in disability (Rho = 0.32, P = 0.07) Neither attendance at therapy nor SIRAS were significantly related to any of the outcomes. The benefits of rehabilitation depended to a large extent on the patient’s exercise behaviour outside of the formal physiotherapy sessions. Hence, more effort should be invested in finding ways to improve patients’ motivation to take responsibility for the success of their own therapy, perhaps by increasing exercise self-efficacy. Whether the “adherence–outcome” interaction was mediated by improvements in function related to the specific exercises, or by a more “global” effect of the programme, remains to be examined.     

The neurobiology of chronic pain states

Plasticity enables alterations in transmission in nociceptive systems. It is this plasticity in the nervous system that can alter the linear relation between noxious stimuli and the perception of pain and is important in the switch from acute to chronic pain. In this way, a number of CNS mechanisms can alter neuronal activity, leading to abnormal ongoing and stimulus-evoked pains due to peripheral and central changes. Peripheral nerves can become sensitized, spinal cord neurons can be rendered hyperexcitable and ascending projections to higher centres can further trigger changes in descending controls from the midbrain and brainstem. Together, these changes, all of which appear to involve reversible physiological and pharmacological plasticity, can alter the relationship between an applied stimulus and the perceived response and so lead to persistent pain states.     

慢性疼痛患者自我同情与心理弹性的相关研究

目的 探讨慢性疼痛患者自我同情与心理弹性的相关性,为临床制订心理干预方案提供理论依据.方法 采用一般资料调查表、自我同情量表、心理弹性量表,对2019年6月至2019年12月青岛市市立医院本部疼痛科195例慢性疼痛患者进行调查研究,分析慢性疼痛患者自我同情与心理弹性的影响因素及相关性.结果 慢性疼痛患者自我同情总分为(...     

罗库溴铵和维库溴铵对离体大鼠膈肌神经肌肉接头终板电位起始衰减的影响

目的探讨罗库溴铵和维库溴铵对大鼠膈肌-膈神经不均匀牵拉标本神经肌肉接头终板电位(EPP)最初衰减的影响。方法健康成年Wistar大鼠,体重160～220g,雌雄不拘。快速处死大鼠制备离体膈肌-膈神经不均匀牵拉标本;记录到正常微终板电位和EPP后,分别观察浓度为4×EC_(95)、2×EC_(95)、1×EC_(95)、0．5×EC_(95)的罗库溴铵和维库溴铵对EPP幅度及串EPP最初衰减的影响。结果罗库溴铵和维库溴铵对EPP幅度和串EPP最初衰减均有不同程度的抑制作用。与维库溴铵相比,罗库溴铵的起效时间缩短,且抑制程度较高。结论罗库溴铵和维库溴铵均有一定程度的突触前抑制作用,与维库溴铵相比,罗库溴铵起效更快、作用更强。     

The late results of antero-lateral cordotomy for pain relief

Summary The operation of antero-lateral cordotomy was carried out on 56 patients with intractable pain between 1968 and 1978. The follow-up of these patients was continued for at least three years or until death to determine the late success of this procedure. Of the 33 patients who underwent surgery for malignant pain 95% of survivors had effective relief on discharge from hospital, the success rate falling to 73% at six months, and 55% at one year of follow-up. The operation was judged successful for patients with malignant disease because of short life expectancy.Thirteen patients had chronic pain from non-malignant conditions, and 85% obtained initial relief, the success rate falling to 35% at one year, and 20% at three years of follow-up.Two patients died from respiratory failure, giving an operative mortality of 3.5%. The results and complications of open cordotomy are compared with those of the percutaneous method, and the role of this procedure discussed in relation to alternative stimulatory analgesic procedures.