Spinal cord stimulation with sympathetically independent pain and sympathetically maintained pain

BACKGROUND: Complex regional pain syndrome (CRPS) is categorized into sympathetically maintained pain (SMP) and sympathetically independent pain (SIP). Spinal cord stimulation (SCS) is a promising approach in the treatment of severely disabling CRPS. Patients with good responses to sympathetic block before SCS are more likely to have positive responses to SCS than those with negative responses. This study compared the effects of SCS in patients with CRPS, of SMP and SIP categories. METHODS: This was a retrospective study of 16 patients (SMP 8, SIP 8) with CRPS who had undergone trials of SCS. Eleven of the patients had permanent SCS device implants, and the pain relief levels at 1 and 6 months were recorded. RESULTS: Sixteen patients with severe, incapacitating, and therapy-resistant CRPS underwent SCS trials. Five patients (SMP 3, SIP 2) had poor pain relief during the trial despite adequate coverage. The remaining 11 patients (SMP 5, SIP 6) had permanent electrode implantation performed under local anesthesia and experienced good pain relief. The difference in VAS reduction was not significant between the two groups at the 1-month follow-up (P = 0.325) and the 6-month follow-up (P = 0.779). CONCLUSIONS: There were no statistically significant differences in VAS pain scores between the two groups. The favorable outcome in all 11 patients with only minor remaining symptoms or without remaining symptoms or severe recurrences suggests that SCS is an efficient treatment in SMP and SIP.

Percutaneous Radiofrequency Thermocoagulation for Trigeminal Neuralgia / 대한마취과학회지

BACKGROUND: Percutaneous radiofrequency thermocoagulation (RFTC) at the trigeminal rootlets has been suggested as a safe and effective treatment for the trigeminal neuralgia.However, no clinical data of RFTC for the trigeminal neuralgia were reported in Korea.The objective of this study was to analyze the treatment efficacy and complications of the RFTC at the trigeminal rootlets for the relief of trigeminal neuralgia. METHODS: The data of RFTC performed in 22 consecutive trigeminal neuralgia patients from November 2004 to February 2007 were retrospectively collected both by the review of medical records and by the telephone interview using a questionnaire.Age, sex, side of the face, and division (s) of trigeminal nerve involved were recorded. Pain relief, recurrence requiring or not requiring reoperation, and type and rate of complications were also evaluated. RESULTS: Six men and 16 women were included in this study.The mean age were 61 +/- 15 years and mean duration of pain were 71.8 +/- 50.5 months.The 11-point-verbal numerical rating scale scores before and after RFTC were 8.4 +/- 2.0 and 1.5 +/- 2.3, respectively (P < 0.05).According to the Kaplan-Meier analysis, the probabilities of remaining pain relief at 6 and 12 months after the procedure were 90.7% and 55.3%, respectively.The overall satisfaction rate was 95% (21/22).Hypesthesia was the more common side effect (36%). CONCLUSIONS: We confirmed that RFTC at the trigeminal rootlets was a minimally invasive and low-risk technique with a high rate of efficacy.

Lead Breakage in Implanted Spinal Cord Stimulation Systems: A case report / 대한마취과학회지

Spinal cord stimulation (SCS) has become an established clinical option for treatment of refractory chronic pain. Current hardware and implantation techniques for SCS are already highly developed and continuously improving, however equipment failures over the course of the long-term treatment are still encountered in a relatively high proportion of treated cases. Percutaneous SCS leads seem to be particularly prone to dislocation and insulation failures. We describe our experience of lead breakage in implanted SCS which was inserted to a complex regional pain syndrome patient who obtained satisfactory pain relief after the revision of SCS.

Effects of Remote Ischemic Preconditioning on the Expressions of NOS and Akt in the Rat Myocardium / 체질인류학회지

Remote ischemic preconditioning (IP), brief tolerating cycles of ischemia and reperfusion in remote non-vital organs, can reduce ischemic injury of the heart. IP induces cardiac protection by down-regulating iNOS or up-regulating eNOS. In addition, Akt has been known to protect myocardium against ischemia-reperfusion injury. This study was undertaken to observe the expression of iNOS, eNOS, Akt and phospho-Akt (p-Akt) in the rat myocardium after IP. Thirty-five weeks-old male Sprague-Dawley rats were divided into control and IP groups. The IP group was further subdivided into 3 groups based on the number of cycles of IP. For IP, left commom iliac artery was occluded 3, 6 and 10 cycles for 5 min of ischemia alternating with 5 min of reperfusion. The rat were sacrificed at 0, 3, 6, 24 and 72 hours of IP and the heart was removed. The expression of iNOS, eNOS, Akt and p-Akt in the rat myocardium was examined by immunohistochemical staining and Western blot analysis. The expression of iNOS was increased by IP and was higher in 10IP groups than 3IP and 6IP group. The expression of eNOS was increased or decreased by IP and was showed no difference with increasing episode of IP. The expression of Akt was decreased by IP at 24 and 72 hours after reperfusion, and showed no differences with increasing episode of IP. The expression of p-Akt was increased by IP and showed no difference with increasing episode of IP. These results suggest that hind limb ischemic preconditioning provides cardiac protection through up-regulation of eNOS and phosphorylation of Akt, however excessive episodes of remote preconditioning may induce the myocardial ischemic injury through overexpression of iNOS.

Pain Management via a Subcutaneous Infusion of Ketamine in a Patient with Complex Regional Pain Syndrome: A case report / 대한통증학회지

Complex regional pain syndrome (CRPS), which is a syndrome that is defined by pain and sudomotor and/or vasomotor instability, is usually resistant to conventional treatment. Here, a case involving a 30-year-old male patient with CRPS type I who showed severe intractable right shoulder pain with allodynia and hyperalgesia despite being treated with oral medications, nerve blocks including thoracic sympathetic neurolysis, and spinal cord stimulation is described. The patient frequently visited the emergency room due to severe uncontrollable breakthrough pain. Although a favorable effect was observed in response to intermittent ketamine infusion therapies that were performed on an outpatient basis, acute exacerbation of pain occurred frequently during the night and could not be controlled. Therefore, subcutaneous ketamine infusion therapy using a patient-controlled analgesic system was attempted and found to effectively control acute exacerbation of pain during 6 weeks of infusion without serious complications.

Percutaneous Pediculoplasty and Balloon Kyphoplasty in a Vertebral Metastatic Cancer Patient: A case report / 대한통증학회지

Percutaneous vertebroplasty and balloon kyphoplasty have been accepted as effective treatment modalities for vertebral compression fractures in patients with vertebral metastasis. However, when these procedures are conducted in patients with lytic lesions of the vertebral pedicle, polymethylmethacrylate leakage through the lytic lesions that occurs during percutaneous pediculoplasty can increase the procedural risks due to the immediate vicinity of neural structures. In spite of this risk, there are not many available reports on safer methods of pediculoplasty. Here we report a case of vertebral metastasis in which the pedicle infiltration of cancer was successfully treated by pediculoplasty using a bone filler device that contained thick bone cement during a balloon kyphoplasty procedure.

Compression Fractures Diagnosed during the Treatment of Postherpetic Neuralgia : A case report / 대한통증학회지

Vertebral compression fractures can occur due to trauma, a malignancy, or most commonly, osteoporosis. These fractures are frequently seen in elderly women; 30% of postmenopausal women are affected by vertebral compression fractures. These fragile fractures frequently result in both acute and chronic pain, but more importantly, are a source of increased morbidity and possibly, mortality. These injuries can be treated both conservatively and with surgery. The use of percutaneous vertebral augmentation offers a minimally invasive approach for the treatment of vertebral compression fractures. We experienced two cases of compression fractures diagnosed during the treatment of thoracic postherpetic neuralgia. Two patients suffering from postherpetic neuralgia with a sharp and stabbing pain in the thoracic dermatomes that was unresponsive to conservative treatment were transferred to our clinic. During the management of postherpetic neuralgia, we incidentally found thoracic compression fractures after obtaining fluoroscopic guided images. After a balloon kyphoplasty, the preoperative pain related to the postherpetic neuralgia was successfully relieved soon after the procedure, and there were no complications.

Experience of the Pediatric Patients Consulted to Pain Center

BACKGROUND: The aim of this study was to investigate the management of pediatric patients who were referred to the pain center. METHODS: The data was collected based on 32 pediatric patients referred to the pain center from March 2002 to August 2006. The number of patients each year, gender distribution, age, requested departments, clinical causes of consultation, and the pain management before and after the consultation were analyzed retrospectively. RESULTS: 32 pediatric patients (19 males and 13 females), aged 3- 17 years, were enrolled in this study. Fifty-six percent of patients were in adolescence. The major need for the consultation was cancer pain (50.0%), myofascial pain syndrome (10.0%) and central pain (10.0%). Before the consultation, 62.1% of the patients were managed by opioid-based medications of which 26.1% were managed by only partial agonists and 29.6% were managed by only PRN. At the pain center, opioid-based medication was also the main treatment. CONCLUSIONS: The number of pediatric patients referred to the pain center has increased. Under this condition, the pain physician should be concerned about pediatric pain patients and their management.

Comparison of the Two Impairment Classes Publicized by the American Medical Association in Complex Regional Pain Syndrome Patients / 대한통증학회지

BACKGROUND: Complex regional pain syndrome (CRPS) is not regarded as an impairment in Korea. Guidelines for rating this impairment are under development by the Korean Academy of Medical Science based on that of the American Medical Association (AMA). However, no studies have been done on the validity of these guidelines in Korea. We therefore evaluated the validity of these guidelines using the criteria from the chapter on the central and peripheral nervous system (CNS-PNS class) and the worksheet for calculating total pain-related impairment score (TPRIS class). METHODS: TPRIS and CNS-PNS classes were calculated through interviews of 28 CRPS patients. The correlation between the two classes was calculated. RESULTS: TPRIS class and CNS-PNS class were well correlated (r = 0.593, P < 0.05). CONCLUSIONS: Both TPRIS or CNS-PNS classes were well correlated and could be used for evaluation of impairment. However, the CNS-PNS class is simpler and quicker to complete.

Perioperative Pain Management in the Patient with Complex Regional Pain Syndrome: A case report / 대한통증학회지

Complex regional pain syndrome (CRPS) is a syndrome of pain and sudomotor or vasomotor instabilities. The perioperative pain management in CRPS patients is very important, as surgery can aggravate preexisting symptoms, especially when performed around the lesion site. Despite the increasing interest in CRPS research, little is known about the optimal perioperative treatment strategy for CRPS patients. Herein, the case of a female CRPS patient, who underwent elective surgery at the lesion site, is reported. As a preemptive analgesia, the patient was satisfactorily managed with two weeks of patient-controlled epidural analgesia, initiated 2 days prior to surgery. The techniques for the prevention of perioperative pain, including preemptive analgesia, as well as its importance, are discussed.

A Case of Balloon Kyphoplasty in High Risk under Cement Leakage: A case report / 대한통증학회지

A vertebral compression fracture can cause chronic back pain, and may also result in progressive kyphosis. The traditional treatments of a vertebral compression fracture include bed rest, analgesics and bracing. Balloon kyphoplasty can restore the vertebral height and allow safe bone cement injection into the cavity made by the balloon, which significantly reduces the risk of cement leakage compared to vertebroplasty. An 82-year-old female patient suffered from severe low back pain. Due to the intractable pain and immobility, which could not be relieved by conventional care, as well as the empty vertebral body associated with communicated fractures of the vertebral surfaces, balloon kyphoplasty, with a thicker bone cement injection than usual with balloon kyphoplasty, was chosen. The preoperative intractable pain and immobility were dramatically relieved soon after the procedure, without any complications.

An Analysis of Paresthesia Areas Evoked by Spinal Cord Stimulation in Relation to the Position of Electrode Tip / 대한통증학회지

BACKGROUND: Spinal cord stimulation is a well-established method for the management of several types of chronic and intractable pain. This form of stimulation elicits a tingling sensation (paresthesia) in the corresponding dermatomes. The goal of this study was to establish a correlation between the spinal levels of the implanted epidural electrodes and the paresthesia elicited due to stimulation of the neural structures. METHODS: Thirty five patients, who received trial spinal cord stimulation, were evaluated. After the insertion of the lead to the selected position, the areas of paresthesia evoked by stimulation were evaluated. RESULTS: Seventy-one percent of cases showed paresthesia in the shoulder area when the tip of the electrode was located between the C2 C4 levels. At the upper extremities, paresthesia was evoked in 86 93% of cases, regardless of the location of the electrode tip within the cervical spinal segments. The most common tip placement of the leads eliciting hand stimulation was at the C5 level. The most common level of electrode tip placement eliciting paresthesia of the anterior and posterior thigh and the foot were at the T7 T12, T10 L1 and T11 L1 vertebral segments, respectively. CONCLUSIONS: Detailed knowledge of the patterns of stimulation induced paresthesia in relation to the spine level of the implanted electrodes has allowed the more consistent and successful placement of epidural electrodes at the desired spine level.

Comparison of Correlation between Bispectral Index and Hemodynamic Index according to Changes of Anesthetics in Children Undergoing Open Heart Surgery / 대한마취과학회지

BACKGROUND: Cardiac anesthesia with cardiopulmonary bypass is associated with an increased risk of awareness. A new approach to intraoperative EEG procession, the bispectral index (BIS), may allow more reliable quantitative assessment of the level of consciousness during anesthesia. We evaluated the relationships between BIS and commonly used indices of depth of anesthesia in children. METHODS: In the isoflurane group, anesthesia was maintained using isoflurane 0.5 1.0 vol% inhalation, whereas the fentanyl group received high dose fentanyl-midazolam infusion. BIS, mean arterial blood pressure, and heart rate were recorded at baseline, at postinduction (Tbaseline), skin incision (Tincis), sternotomy (Tsterno), aortic cannulation (Tcannul), nadir temperature (Tnadir), immediate post-CPB (TpostCPB), sternal wire (Twire), and at skin closure (Tclose). RESULTS: BIS showed a significant change over time (P < 0.001), with significant differences between groups (P = 0.04). BIS increased significantly during the immediate post-CPB phase (TpostCPB versus Tbaseline, Tnadir, P < 0.01). No correlations were found between BIS and changes in heart rate or mean arterial pressure during surgery. BIS was higher in the fentanyl group than in the isoflurane group at Tincis, Tcannul, and Twire (P < 0.05). CONCLUSIONS: Even though BIS was relatively lower in the isoflurane group compared to the fentanyl group, we were still unable to demonstrate a relationship between the BIS and hemodynamic indices depth for any group. While the increase in BIS during the rewarming phase could reflect an increase in conscious level, larger prospective studies with postoperative memory test for awareness are necessary.