Radiofrequency thermocoagulation of the thoracic splanchnic nerve in functional abdominal pain syndrome -A case report-.

The thoracic splanchnic nerve block has been used in managing abdominal pain, especially for pains arising from abdominal cancers. A 27-year-old male patient who had a constant abdominal pain was referred to our clinic for pain management but had no organic disease. The numeric rating scale (NRS) for pain scored 7/10. We applied a diagnostic thoracic splanchnic nerve block under the diagnosis of functional abdominal pain syndrome. Since the block reduced the pain, we applied a radiofrequency thermocoagulation at the T11 and T12 vertebral level. Thereafter, his symptoms improved markedly with pain decreasing to an NRS score of 2-3/10. Hereby, we report a successful management of functional abdominal pain via radiofrequency thermocoagulation of the thoracic splanchnic nerves.

A comparison of the effects of preanesthetic administration of crystalloid versus colloid on intrathecal spread of isobaric spinal anesthetics and cerebrospinal fluid movement.

BACKGROUND: Movement of the cerebrospinal fluid (CSF) is one of the most important factors in determining the intrathecal spread of isobaric spinal anesthetics. Preanesthetic administration of either crystalloid or colloid immediately before spinal anesthesia (preload) may result in different CSF pulsatile movement because of their different physical properties. We examined whether preload of crystalloid versus colloid may have different effects on the intrathecal spread of isobaric spinal anesthetics as a result of their different CSF dynamics regarding its pulsatile movement. METHODS: In a clinical study of isobaric spinal anesthesia, patients were allocated into 1 of 2 groups according to preload with either crystalloid (n = 30) or colloid (n = 30) before spinal anesthesia with 0.5 isobaric tetracaine. The pulsatile movements of CSF at the L2-3 intervertebral space and midportion of the aqueduct of Sylvius were also examined by magnetic resonance images in healthy volunteers (n = 23) at 0, 30, and 60 minutes after administering either crystalloid or colloid. RESULTS: In the clinical study, the time to reach the peak sensory block level was delayed significantly in the crystalloid preload group (27.2 ± 17.8 minutes; P < 0.01) compared with the colloid preload group (13.9 ± 7.0 minutes). The median sensory block levels of the crystalloid preload group at 15 minutes (T10, P < 0.05) and 20 minutes (T9.5, P < 0.05) were significantly lower than those (T8, T7, respectively) of the colloid preload group. In the magnetic resonance imaging study, cranially directed CSF pulsatile movement decreased significantly at the L2-3 intervertebral intrathecal space at 30 minutes after crystalloid administration, but not after colloid administration. The CSF production rate significantly increased at 30 minutes (637 µL/min, P < 0.05) after crystalloid preload compared with the baseline measurement (448 µL/min), and then slightly decreased (609 µL/min) at 60 minutes. In the colloid preload group, the CSF production rate was not statistically significant compared with the baseline measurement (464, 512, and 542 µL/min at baseline, 30, and 60 minutes, respectively). CONCLUSIONS: Compared with a colloid preload, which may be comparable to the no-preload condition, crystalloid preload prolonged the time to reach the peak sensory block level in isobaric spinal anesthesia, which might have been caused by a significant decrease in CSF pulsatile movement. This attenuated CSF pulsatile movement in the crystalloid preload group might have resulted from significant increases of CSF production.

Cardiovascular effects and predictability of cardiovascular collapse after repeated intravenous bolus injections of absolute ethanol in anesthetized pigs.

PURPOSE: To evaluate the effects of repeated intravenous bolus injections of absolute ethanol on cardiopulmonary hemodynamic changes and to investigate the predictability of ethanol-induced cardiovascular collapse in anesthetized pigs. MATERIALS AND METHODS: Twenty pigs aged 3-6 months and weighing 28-38 kg were enrolled in the study. Absolute ethanol (0.1 mL/kg of body weight) was repeatedly injected through the inferior vena cava central to the renal vein at 10-minute intervals up to a total volume of 1.0 mL/kg. The subjects were divided into a cardiovascular collapse group and a no-collapse group according to the development or absence of cardiac collapse. RESULTS: Among the 20 pigs, 12 died before the final injection. Hemodynamic parameters measured immediately before the injection of absolute ethanol did not differ between the cardiovascular collapse group and the no-collapse group except that among animals with cardiovascular collapse, the injection immediately before the one causing cardiovascular collapse resulted in significant increases in the following hemodynamic parameters: mean pulmonary arterial pressure (P < .01), pulmonary vascular resistance (P = .04), and right ventricular end-diastolic volume (P = .02). No such increases were observed in the no-collapse group. CONCLUSIONS: Hemodynamic profiles in pigs obtained immediately before intravenous injection of absolute ethanol did not predict the subsequent occurrence of cardiovascular collapse except after the injection immediately preceding the one resulting in cardiovascular collapse. In this animal model, significant increases in select hemodynamic parameters occurred after the injection immediately preceding the one resulting in cardiovascular collapse.

Breakage of a thoracic epidural catheter during its removal -A case report-.

The breakage of an epidural catheter is a rare complication during the removal of a thoracic epidural catheter. There are many causes to breakage of an epidural catheter, such as the characteristics of the catheter itself, patient's factors (anatomy, position during insertion and removal of the catheter, and the BMI), and the difficulty of the procedure. Surgical removal is considered if there is a possibility that the retained catheter might cause neurological problems. We experienced a breakage of an epidural catheter during its removal, which led to surgical intervention. To prevent the catheter breakage during its removal, the catheter should be withdrawn without excessive tension. In addition, an understanding of the patient's anatomy is essential.

Determination of adequate entry angle of lumbar sympathetic ganglion block in korean.

BACKGROUND: The target of lumbar sympathetic ganglion block is the anterolateral surface of the L2, 3 and 4 vertebral bodies, where the lumbar sympathetic ganglion usually lies. In most cases, a block-needle is inserted approximately 5-8 cm lateral to spinous process on the skin and directed to the anterolateral surface of vertebral body obliquely. The purpose of this study is to determine the safe entry angle and entry point in Korean by using the abdominal CT scan images. METHODS: The abdominal CT images of eighty five patients were recruited to this study. The minimal angle aimed at the lumbar sympathetic ganglion that can pass through the lateral aspect of body and maximal angle that avoids puncturing the kidney, ureter or retroperitoneal space were measured. The distance from midline to skin entry point was also measured. RESULTS: There was no significant difference in entry angle among L2, 3, and 4 level. The entry angle was similar in the right and left side, and in males and females. The entry angle of old age group was significantly smaller than that of young age group. The calculated safe entry angle was 30.5 +/- 0.4 degrees and entry point was 7.7 +/- 0.2 cm and 6.7 +/- 0.1 cm lateral from midline in males and females respectively. CONCLUSIONS: These measurements can be used as a reference for lumbar sympathetic ganglion block and radiofrequency lesioning. Prior to performing the lumbar sympathetic ganglion block for cancer patients, the abdominal CT scan should be reviewed to prevent complications.

Efficacy of milrinone versus nitroglycerin in controlling pulmonary arterial hypertension induced by intravenous injections of absolute ethanol in anesthetized dogs.

PURPOSE: To compare the attenuating effects of milrinone versus nitroglycerin on pulmonary artery pressure (PAP) increase caused by repeat intravenous bolus injection of absolute ethanol in anesthetized dogs. MATERIALS AND METHODS: Twenty-four dogs were randomly distributed into three groups: a control group (group C), a nitroglycerin group (treated with a continuous infusion of nitroglycerin at 5.0 microg/kg/min; group N), and a milrinone group (treated with a continuous infusion of milrinone at 3.0 microg/kg/min after an initial bolus dose of 100 microg/kg; group M). Absolute ethanol (0.1 mL/kg) was injected at 10-minute intervals via a 5-F angiographic catheter advanced into the proximal portion of the inferior vena cava. Immediately before and after each intravenous injection of absolute ethanol, hemodynamic values were obtained through a pulmonary arterial catheter. RESULTS: Group M showed more stable hemodynamic values of systolic, mean, and diastolic PAP and pulmonary vascular resistance (PVR) compared with groups C and N. In addition, group M showed significantly higher values of cardiac output versus group C at 10 minutes after the 10th bolus of ethanol. After restoration of spontaneous breathing, group M also showed the least hemodynamic changes in systolic, mean, and diastolic PAPs and PVR among the groups. CONCLUSIONS: Although a continuous infusion of nitroglycerin or milrinone effectively prevented cardiovascular deterioration, milrinone was superior to nitroglycerin in managing the acute hemodynamic changes that resulted from repeated intravenous bolus injections of absolute ethanol (0.1 mL/kg) in healthy anesthetized dogs.

Analgesic effects of ketamine infusion therapy in korean patients with neuropathic pain: A 2-week, open-label, uncontrolled study.

BACKGROUND: The overexcitation of the N-methyl-D-aspartate receptor complex appears to play a critical role in the development of neuropathic pain, and ketamine acts as an antagonist to that receptor. Some publications have reported on the prominent relief of neuropathic pain with intravenous or subcutaneous ketamine infusions or a single-dose intravenous ketamine injection despite adverse effects. OBJECTIVES: The primary objective of this study was to determine the analgesic effect of intravenous ketamine infusion therapy for neuropathic pain refractory to conventional treatments. Secondary objectives included identifying the variables related to the analgesic effect and the pain descriptors susceptible to ketamine infusion. METHODS: This 2-week, open-label, uncontrolled study was conducted in Korean patients with neuropathic pain recruited from the Samsung Seoul Hospital (Seoul, Republic of Korea) outpatient pain management unit. Patients were required to have a pain severity score >5 (visual analog scale [VAS], where 0 = no pain and 10 = worst pain imaginable) over a period of ≥1 month while on standard treatment. The patients were required to have shown no benefit from standard treatment and no pain relief lasting over 1 month. The ketamine infusion therapy was composed of 3 sessions performed consecutively every other day. Midazolam was administered concomitantly to reduce the occurrence of central nervous system-related adverse events (AEs) secondary to ketamine. Each session was as follows: ketamine 0.2 mg/kg and midazolam 0.1 mg/kg were administered intravenously for 5 minutes as a loading dose, followed by a continuous infusion of ketamine 0.5 mg/kg/h and midazolam 0.025 mg/kg/h for 2 hours. AEs were assessed in the following ways: close monitoring of ECG, blood pressure, oxygen saturation, and evaluating the need for treatment of AEs during infu- sion and until discharge by an attending anesthesiologist; an open question about discomfort at the end of each session; spontaneous reports about AEs during each session; and the patients' and caregivers' checklist of AEs occurring at home for 2 weeks after discharge. All the descriptors of pain expressed by the patients in Korean were recorded and translated into appropriate English terminology on the basis of the literature on Korean verbal descriptors of pain. Each of the translated pain descriptors was then classified into 1 of 18 sensory items. RESULTS: The overall VAS score for pain decreased from a baseline mean (SD) of 7.20 (1.77) to 5.46 (2.29) (P < 0.001) 2 weeks after treatment in 103 patients (53 males and 50 females; mean age, 52.56 [17.33] years) who completed the study. Variables such as age, sex, and the duration and diagnosis of pain were not found to be associated with analgesic effect. Seven of the 18 pain descriptors were found to have a significant response to ketamine infusion treatment between baseline and 2 weeks follow-up: burning pain (P = 0.008); dull, aching pain (P < 0.001); overly sensitive to touch (P = 0.002); stabbing pain (P = 0.008); electric pain (P = 0.031); tingling pain (P < 0.001); and squeezing pain (P < 0.001). A total of 52 patients reported AEs: 33 during infusion and 44 during recovery and up to 2 weeks follow up. The most commonly reported AEs were snoring (15 [15%]) during infusion and dizziness (43 [42%]) during recovery. CONCLUSIONS: Ketamine infusion therapy was associated with reduced severity of neuropathic pain and generally well tolerated for up to 2 weeks in these patients with neuropathic pain refractory to standard treatment. Variables such as sex, age, and the diagnosis and duration of pain had no association with the analgesic effect of this treatment. Randomized controlled trials are needed to evaluate the efficacy and tolerability of treatment with ketamine infusion.

Is intravenous patient controlled analgesia enough for pain control in patients who underwent thoracoscopy?

This prospective randomized study was conducted to evaluate the efficacy of two common analgesic techniques, thoracic epidural patient-controlled analgesia (Epidural PCA), and intravenous patient-controlled analgesia (IV PCA), in patients undergoing lobectomy by the video-assisted thoracic surgical (VATS) approach. Fifty-two patients scheduled for VATS lobectomy were randomly allocated into two groups: an Epidural PCA group receiving an epidural infusion of ropivacaine 0.2%+fentanyl 5 microg/mL combination at a rate of 4 mL/hr, and an IV PCA group receiving an intravenous infusion of ketorolac 0.2 mg/kg+fentanyl 15 microg/mL combination at a rate of 1 mL/hr. Pain scores were then recorded using the visual analogue scale at rest and during motion (VAS-R and VAS-M, 0-10) for five days following surgery. In addition, we measured the daily morphine consumption, forced vital capacity (FVC), forced expiratory volume in 1 second (FEV(1)), satisfaction score, and the incidence of side effects. Thirty-seven patients out of 52 completed the study (18 in the Epidural PCA group, 19 in the IV PCA group). There were no differences in the pain scores, analgesic requirements, pulmonary function, satisfaction score, and the incidence of side effects between groups. This indicates that IV PCA and Epidural PCA are equally effective to control the postoperative pain after VATS lobectomy, which suggests that IV PCA may be used instead of Epidural PCA.

Fluoroscopy-guided pudendal nerve block and pulsed radiofrequency treatment : A case report.

Pudendal nerve block (PNB) is performed for differential diagnosis and treatment of chronic pelvic and perineal pain. Several block methods, such as transvaginal, transperineal, computerized tomography-, ultrasound- and fluoroscopy-guided approach are currently under practice. Compared to others, a fluoroscopy-guided approach has several advantages, such as its relatively low cost, facility and ease of landmark recognition. We depicted a fluoroscopy-guided PNB technique to selectively block and elaborate a pulsed radiofrequency treatment in a 51-year-old man with chronic pelvic and perineal pain. The patient had undergone a ganglion of impar block with a limited pain relief. Thereafter, a PNB was performed and the pain was relieved significantly for 2 weeks. Further PNB with a pulsed radiofrequency treatment reduced the pain for more than 8 weeks. The pain relief sustained up to the time of this report. The fluoroscopy-guided PNB and pulsed radiofrequency treatment allowed simplicity in manipulation and precision in performing the procedures with a favorable outcome.

Intravascular injection in lumbar medial branch block: a prospective evaluation of 1433 injections.

BACKGROUND: The successful outcome and validity of lumbar medial branch block (MBB) are largely dependent on technique accuracy. Intravascular uptake of injectate causes a false-negative response to block and is associated with various possible complications. In the current study, we prospectively evaluated the incidence of, and the factors associated with, intravascular injection during block. In addition, we assessed the efficiencies of generally accepted safety measures, such as preinjection aspiration and intermittent fluoroscopy to avoid intravascular injections. METHODS: We prospectively examined 1433 lumbar MBBs in 456 patients performed by seven physicians. Aspiration test, spot radiography, and contrast injection under real-time fluoroscopic visualization were performed sequentially without repositioning the needle. Incidences of blood flashback and the presence of intravascular contrast spread on spot radiographic images and during real-time fluoroscopy were checked. The factors studied for intravascular injection included physician experience, patient age and sex, needle gauge, and block spinal level. RESULTS: No specific factors were found to affect the incidence of intravascular uptake during block. The overall incidence of intravascular uptake was 6.1% per nerve block (88/1433), and 30 of these were predicted by preinjection aspiration (sensitivity = 34.1%) and 52 by spot radiography (sensitivity = 59.1%). CONCLUSIONS: The aspiration test with or without spot radiography frequently missed the intravascular uptake of contrast during lumbar MBBs. We strongly advocate the use of real-time fluoroscopy during contrast injection to increase diagnostic and therapeutic value and to avoid possible complications.

The neurological safety of epidural gabapentin in rats: a light microscopic examination.

Gabapentin acts primarily on the central nervous system. Therefore, we hypothesized that the direct epidural administration of gabapentin could have various advantages over its oral administration with respect to required dose, side effects, and efficacy. However, before administering gabapentin into the epidural space in a clinical setting, its neurotoxicity must be examined in animals. Thus, we evaluated neurotoxicity of epidural gabapentin by observing behavioral and sensory-motor changes, and by histopathological examinations of spinal cords and dorsal root ganglia in the rat. Twenty-seven rats were randomly divided into 3 groups, which were administered 0.3 mL (30 mg) of epidural gabapentin (group G, n = 9) and the same volume of epidural alcohol (group A, n = 9) or normal saline (group N, n = 9). No rats in groups G and N showed sensory-motor dysfunction, behavioral change, or histopathological abnormalities over a 3-wk observation period, whereas all rats in group A showed abnormalities. We conclude that the direct epidural injection of gabapentin in rats did not show any neurotoxic evidence in terms of sensory-motor functions and behavior, or by a microscopic histopathological evaluation. This study represents a first promising step toward the trial of epidural gabapentin in a clinical setting.

Thoracic epidural anesthesia does not improve the incidence of arrhythmias after transthoracic esophagectomy.

OBJECTIVE: The incidence of arrhythmias related to an esophagectomy is high, and its clinical significance has been well accepted. Thoracic epidural anesthesia (TEA) can modulate the sympathetic tone and neuroendocrine responses associated with major operation. This study was aimed to evaluate the effects of TEA on the incidence of arrhythmias in transthoracic esophagectomy patients. METHODS: The records of 185 patients who underwent the Ivor-Lewis operation between 2001 and 2004 by the same operator were reviewed. The patients were divided into three groups. Group 1 (n = 58) received post-operative intravenous patient-controlled analgesia without TEA. Group 2 (n = 55) received postoperative epidural patient-controlled analgesia using local anesthetics. The patients of group 3 (n = 72) were anesthetized intra-operatively by the combination technique of thoracic epidural bupivacaine and inhalation agents, and post-operative pain control was done in the same way with group 2. RESULTS: Arrhythmias occurred 29.3, 50 and 29.2% in groups 1, 2 and 3, respectively. There were no statistical differences in the incidences of arrhythmias among the three groups. CONCLUSIONS: This result shows that TEA was not beneficial to reduce the incidence of arrhythmias in the transthoracic esophagectomy patients.

The neurotoxicity of epidural hyaluronic acid in rabbits: a light and electron microscopic examination.

UNLABELLED: Because hyaluronic acid (HA) has an antiinflammatory effect and prevents and/or reduces tissue adhesion, we believed it possible that epidurally-administered HA during epidural adhesiolysis procedures could alleviate pain in patients with chronic lower back pain. Therefore, we performed this pre-clinical trial evaluation of epidurally-administered HA neurotoxicity by light microscopy (LM) and electron microscopy (EM) in rabbits. Twenty rabbits were randomly divided into two groups, a normal saline (NS) group (n = 10) and a HA group (n = 10). Saline (0.2 mL/kg of 0.9% solution) and the same volume of HA were injected into the epidural space. No rabbits showed any sensory-motor or behavior change during the 3-wk period, except for one rabbit in the NS group that showed decreased appetite, activity, and weight loss. By LM, two rabbits in the NS group showed abnormal findings considered to be the result of trauma and infection associated with epidural catheterization. EM findings showed no significant neurotoxic findings in either group. In conclusion, epidurally-administered HA did not cause neurotoxicity in rabbits. IMPLICATIONS: We performed a pre-clinical trial evaluation on the neurotoxicity of hyaluronic acid administered epidurally by light microscopy and electron microscopy in rabbits. Epidurally-administered hyaluronic acid did not produce any sign of neurotoxicity in rabbits.