Challenges in removing an aged spinal cord stimulator: A case study of complete fracture in a 9-year-old S-series paddle lead.

INTRODUCTION: This case report presents an instance of an S-Series™ slim paddle lead fracturing during extraction, highlighting potential risks associated with the removal of this lead. CASE REPORT: A 47-year-old male with complex regional pain syndrome type 2, unresponsive to pharmacotherapy, had undergone the implantation of two spinal cord stimulator (SCS) leads, an Octrode™ cylindrical and an S-series™ slim paddle, using the Epiducer™ system (St Jude Medical) 9 years earlier, with a subsequent intrathecal baclofen pump installed 1 year after SCS. Initially, these interventions stabilized the patient's pain symptoms. However, the diminishing effectiveness of SCS, coupled with a decrease in battery life and increased opioid consumption, necessitated recent surgical procedures. These included the removal and replacement of the implantable pulse generator (IPG) and leads to improve pain management and ensure MRI compatibility. During the removal of the S-series™ slim paddle type lead, complications arose, leading to the retention of an electrode fragment, which necessitated abandoning the replacement of both the IPG and lead. Post-surgical assessments revealed no new neurological impairments, and imaging studies confirmed the stable position of the retained fragment. The patient was discharged with a continued comprehensive pain management plan. CONCLUSION: This case highlights the challenges and risks of percutaneous removal of slim paddle type leads, emphasizing the need for careful procedural planning and consideration of surgical options to avoid complications. Further research is needed to evaluate the long-term durability and removal risks of various SCS lead types.

Atypical Course of Vertebral Artery Identified by Ultrasound Prescan before Performing a Stellate Ganglion Block.

Ultrasound provides direct visualization of blood vessels and soft tissues around the sympathetic chain and potentially minimizes injury to these critical anatomic structures when performing stellate ganglion block (SGB). We report an atypical left vertebral artery course detected during an ultrasound prescan before performing a SGB. The left vertebral and inferior thyroid arteries were identified on the longus colli muscle's ventral surface at the C6 level. This report was the first to demonstrate ultrasound images of a vulnerable vertebral artery to intravascular injection. The study emphasized the importance of identifying the sonoanatomy before performing procedures involving the anterior cervical vertebrae.

Leriche Syndrome Misdiagnosed as Complex Regional Pain Syndrome in a Patient with Neuropathic Pain Caused by a Chip Fracture: A Case Report.

INTRODUCTION: Leriche syndrome is an aortoiliac occlusive disease caused by atherosclerotic occlusion. We report a case of Leriche syndrome with a fracture that was suspected as complex regional pain syndrome (CRPS), as the post-traumatic pain gradually worsened in the form of excruciating neuropathic pain. CASE REPORT: A 52-year-old woman with a history of hypertension was referred to the Department of Pain Medicine from a local orthopedic clinic because of suspected CRPS for excruciating neuropathic pain for one month. She complained of gait dysfunction and severe pain in the right foot following an incident of trauma with the right first toe. The average pain intensity assessed using the visual analog scale (VAS) was 90 (0: no pain, 100: the worst pain imaginable), and the neuropathic pain was evident as a score of 6/10 on Douleur neuropathique 4. Allodynia, hyperalgesia, blue discoloration of the skin, asymmetric temperature change (1.38 °C), and edematous soft tissue changes were observed. Ultrasonography showed a chip fracture in the first distal phalanx of the right first toe. The diagnosis was most probably CRPS type I according to the Budapest research criteria for CRPS. However, multiple pain management techniques were insufficient in controlling the symptoms. A month and a half later, an ankle-brachial index score of less than 0.4 suggested severe peripheral artery disease. Computed tomography angiography showed total occlusion between the infrarenal abdominal aorta and the bilateral common iliac arteries. Therefore, she underwent aortic-bifemoral bypass surgery with a diagnosis of Leriche syndrome. Three months after the surgery, the average pain intensity was graded as 10 on the VAS (0-100), the color of the skin of the right first toe improved and no gait dysfunction was observed. CONCLUSION: A chip fracture in a region with insufficient blood flow could manifest as excruciating neuropathic pain in Leriche syndrome.

Prediction of the Cervical Epidural Space Depth from the Skin Using Cervical X-Ray, During Cervical Epidural Block with Paramedian Approach.

Objective: The purpose of this study is to compare the actual needle depth measured during cervical epidural block (CEB) with the predicted needle depth measured through a cervical flexion x-ray image at the paramedian approach. Methods: The study was conducted based on the medical records of patients who underwent CEB at the pain clinic of Haeundae Paik Hospital. The actual needle distance (AD) was recorded after each successful CEB. The distance from the spinolaminar line to the skin, predicted median depth (PMD), was measured using lateral x-ray images. The medial to lateral distance (MLD), which is the distance from the midline of the spine to the needle insertion point, was measured using anteroposterior (AP) x-rays. The predicted paramedian depth (PPD) was calculated using the Pythagorean formula. The PMD represents the expected depth of the median approach, while the PPD represents the expected depth of the paramedian approach. The PMD, PPD, and AD were compared with each other. Results: Concordance correlation coefficient (CCC) and Bland-Altman analysis were obtained for PMD and PPD. The CCC value of PMD was measured as 0.829, and the CCC value of PPD was measured as 0.830. In the Bland-Altman analysis, PPD was measured at -0.13 ± 8.37 mm, and PMD was measured at 1.29 ± 8.38 mm. Conclusion: When performing CEB through the paramedian approach, the depth can be predicted using a cervical flexion x-ray. At this time, the PMD can also be used to predict the depth during the paramedian approach.

Spontaneous intracranial hypotension following spinal anesthesia initially misdiagnosed as postdural puncture headache.

Spontaneous intracranial hypotension (SIH) is not rare, but its diagnosis remains challenging. SIH tends to be misdiagnosed as postdural puncture headache when orthostatic headache develops subsequent to spinal anesthesia because both have similar symptoms. We report the case of a 35-year-old man with orthostatic headache following spinal anesthesia, who did not respond to conventional therapy for postdural puncture headache. SIH was confirmed after epidural fluid collection was identified at the thoracic spine level on magnetic resonance myelography. Physicians must consider SIH despite a history of neuraxial block. Diagnostic work-up is necessary to identify potential cerebrospinal fluid leakage in refractory cases.

Effect of Remifentanil on Postoperative Vomiting After Strabismus Surgery in Preschool Children: A Prospective Randomized Controlled Trial.

Background: Strabismus surgery and the use of opioid are risk factors of postoperative vomiting. We evaluated whether there is a dose-dependent effect of remifentanil on the incidence of postoperative vomiting. Methods: Sixty pediatric patients who were scheduled for strabismus surgery were enrolled. Patients were randomly divided into three groups; Group H (high-dose remifentanil group), Group L (low-dose remifentanil group), and Group C (control group). After endotracheal intubation, patients in the Group H and L received an intravenous bolus dose of remifentanil of 1.0 µg/kg and 0.5 µg/kg over 2 min, respectively. Group H and L patients received a continuous infusion of remifentanil (0.1 µg/kg/min) during the surgery. The patients in Group C did not have any dose of remifentanil. Intravenous fentanyl (1 µg/kg) was administered to the patients for postoperative pain control. Results: The primary outcome was a difference of the incidence of postoperative vomiting within 24 hours after surgery. There was no significant difference in incidence of postoperative vomiting between three groups. The degree of emergence agitation and postoperative pain did not show any significant difference between three groups. Conclusions: The intraoperative administration of remifentanil did not show dose-dependent effect on postoperative vomiting in pediatric strabismus surgery.

Varicella-Zoster Virus Reactivation During the Incubation Period for Scrub Typhus: A Case Report.

BACKGROUND Herpes zoster caused by the reactivation of latent varicella-zoster virus is thought to result from the waning of specific cell-mediated immunity. Scrub typhus, an acute infectious disease caused by Orientia tsutsugamushi, affects multiple organs and is characterized by microangiopathies that result in significant vascular leakage and subsequent end-organ injury. Very few cases of reactivation of the varicella-zoster virus following scrub typhus occurrence have been reported. Furthermore, no previous studies have directly investigated whether Orientia tsutsugamushi infection is a potential risk factor for herpes zoster. CASE REPORT We present the case of a 64-year-old woman without a previous illness who simultaneously developed herpes zoster of the thoracic dermatome and scrub typhus. Clinical symptoms of scrub typhus appeared during the treatment course for herpes zoster symptoms. Based on positive virus antibody test results, the patient was diagnosed with scrub typhus. This is a unique case of reactivation of the varicella-zoster virus that occurred during a silent incubation period for scrub typhus. CONCLUSIONS This report indicates the possibility of reactivation of latent varicella-zoster virus following Orientia tsutsugamushi infection, although the relationship between the 2 remains undetermined. Physicians should be aware that scrub typhus might be a potential determinant of varicella-zoster virus reactivation.

Effect of phenylephrine infusion on hypotension induced by the beach chair position: A prospective randomized trial.

BACKGROUND: The beach chair position (BCP), used during shoulder surgery, is associated with hypotension, bradycardia, and risk of cerebral hypoperfusion. Phenylephrine is commonly used as a first treatment of choice of intraoperative hypotension during surgery. We evaluated the hemodynamic effects of 2 doses of intravenous phenylephrine infusion administered before being placed in BCP for arthroscopic shoulder surgery. The primary endpoint was the incidence of hypotension after positional change. METHODS: Sixty-six patients were randomized to receive either intravenous normal saline (group NS) or intravenous phenylephrine infusion (0.5 µg/kg/min, group LP or 1.0 µg/kg/min, group HP) for 5 minutes before being placed in the BCP. Mean arterial pressure(MAP), heart rate, stroke volume variation, and cardiac index were measured before and after positional change. RESULTS: The total incidence of hypotension after the BCP was 93.65%, but was not significantly different among the 3 groups. However, there was a significant difference in trends between the groups for MAP for 5 minutes after BCP (P = .028). Comparison of changes in MAP at 1 minute compared to post-induction MAP was significantly different between group HP and group NS (P = .014). CONCLUSION: Infusion of 0.5 and 1.0 µg/kg/min of phenylephrine for 5 minutes before the BCP has no preventive effect for incidence of hypotension. However, this study showed that 1.0 µg/kg/min of phenylephrine infusion for 5 minutes can attenuate the severity of hypotension.

Effect of depth of anesthesia on the phase lag entropy in patients undergoing general anesthesia by propofol: A STROBE-compliant study.

The PLEM100 (Inbody Co., Ltd., Seoul, Korea) is a device for measuring phase lag entropy (PLE), a recently developed index for the quantification of consciousness during sedation and general anesthesia. In the present study, we assessed changes in PLE along with the level of consciousness during the induction of general anesthesia using propofol. PLE was compared with the bispectral index (BIS), which is currently the most commonly used index of consciousness.After obtaining Institutional Review Board approval and written informed consent, we enrolled 15 patients (8 men, 7 women; mean age: 37 ±â€Š9 years; mean height: 168 ±â€Š8 cm; mean weight; 68 ±â€Š11 kg) undergoing nasal bone reduction. PLE and BIS sensors were attached simultaneously, and general anesthesia was induced via target-controlled infusion (TCI) of propofol. PLE and BIS scores were recorded when the calculated effect site concentration shown on the TCI pump was equal to the target concentrations of 1.5, 2.0, 2.5, 2.8, 3.0, 3.2, 3.4, and 3.5 µg/mL (and at each 0.1 µg/mL increase, thereafter). Observer's Assessment of Alertness/Sedation (OAA/S) scores were also recorded until unconsciousness was achieved. Throughout the anesthesia period, all pairs of PLE and BIS data were collected using data acquisition software.The partial correlation coefficients between OAA/S scores and PLE, and between OAA/S scores and BIS were 0.778 (P < .001) and 0.846 (P < .001), respectively. Throughout the period of anesthesia, PLE and BIS exhibited a significant positive correlation. The partial correlation coefficient prior to the loss of consciousness was 0.838 (P < .001), and 0.669 (P < .001) following the loss of consciousness. Intra-class correlation between the 2 indices was 0.889 (P < .001) and 0.791 (P < .001) prior and following the loss of consciousness, respectively.PLE exhibited a strong and predictable correlation with both BIS and OAA/S scores. These results suggest that PLE is reliable for assessing the level of consciousness during sedation and general anesthesia.