Electroanalgesia by transcutaneous stimulation (TNS). Response to the naloxone test

The authors, after a review of the literature about TNS, suggest the comparison between three different TNS techniques from two points of view: A) pain relief estimate; B) Response to Naloxone Test. To this purpose a impulse generator delivered a biphasic square-wave stimulus with duration of 0.40 msec and amplitude (peak to peak) to 130 mVolt, was used. TNS techniques used are so characterized 1) Frequency 80 Hz; Duration 30'; 2) Frequency 80 Hz; Duration over 120'; 3) Frequency 2/4 Hz; Duration over 120'. Although the techniques used for Group (1) provided the best numerical result in the evaluation of the pain relief, endorphine activity cannot be maintained owing to Naloxone Test negativity. pain relief of (2) and (3) Group was statistically significant although not numerically at the same level of (1) Group. In the laters, on the contrary, positivity of Naloxone Test seems to hint at the activation of endorphine. This fact suggest to the authors hypothesis in the purpose to spot TNS site of action.

Cerebrospinal fluid nitric oxide metabolites are novel predictors of pain relief in degenerative lumbar diseases.

This study was undertaken to determine whether or not nitric oxide metabolites (NO(2)(-) plus NO(3)(-): NOx levels) in cerebrospinal fluid (CSF) would be predictors of treatment outcome in patients with degenerative lumbar diseases (DLD) including lumbar disc herniation (LDH) and lumbar spinal canal stenosis (LCS). The NOx levels in CSF were measured using an NO analyzer based on the Griess method. Six healthy volunteers and 18 patients with painless diseases were included in the control group. The pre- and postoperative NOx levels in 25 DLD patients, who underwent herniotomy for LDH (17 patients) or selective decompression for LCS (eight patients), were analyzed. The postoperative follow-up periods were approximately 8 months. Nineteen of 25 DLD patients, whose preoperative NOx levels were two standard deviations higher than the mean NOx levels of an age-matched control group, were included in an NO elevated (NOE) group. Among the 25 DLD patients, the preoperative NOx levels in six patients (young LDH group) were within the normal range. The pain-related Japanese Orthopaedic Association score and the Hirabayashi recovery rate were respectively used to evaluate the pain severity and the degree of pain relief. The preoperative and changes of postoperative NOx levels in the NOE group were negatively correlated with the Hirabayashi recovery rate. Normal postoperative NOx levels and excellent pain relief were achieved in young DLD patients. In conclusion, the preoperative and changes in postoperative NOx levels are quantitative predictors of postoperative pain relief in DLD patients.

Pituitary alcohol injection for cancer pain. Use in a district general hospital.

The use of trans-sphenoidal pituitary alcohol injection was assessed in a district general hospital for the treatment of diffuse bilateral cancer pain in 26 patients. Fourteen patients received a total of 43 injections. Hormonal and non-hormonal dependent cancers were treated, with complete pain relief in ten patients and partial relief in a further seven patients. The duration of relief was variable, and usually less than 6 weeks, although two patients had complete pain relief for 5 and 7 months respectively. No cases of meningitis or cerebrospinal fluid rhinorrhoea occurred. Nasal antiseptics and vasoconstrictors were not used. Temporary pupil dilatation occurred in eight patients, of whom one had prolonged blurred vision for small print. Transient diabetes insipidus was common (53%), although only five patients needed permanent treatment. Death from their disease occurred in 65% of patients within 3 months. Survival was shorter than in series from specialist centres, suggesting later referral for pain relief. The technique is an inexpensive and valid form of treatment for cancer pain in a district hospital, but should not be undertaken lightly in view of the possible complications.

Pancreatoduodenectomy for chronic pancreatitis: anatomic selection criteria and subsequent long-term outcome analysis.

OBJECTIVE: The authors sought to provide a framework through outcome analysis to evaluate operations directed toward the intractable abdominal pain of severe chronic pancreatitis centered in the pancreatic head. Pancreatoduodenectomy (PD) was used as an example. SUMMARY BACKGROUND DATA: Head resection for severe chronic pancreatitis is the treatment of choice for a ductal system in the head obliterated by severe disease when associated with intractable abdominal pain. To evaluate the effectiveness of promising head resection substitutes for PD, a framework is necessary to provide a reference standard (i.e., an outcome analysis) of PD. METHODS: Inclusion criteria were severe chronic pancreatitis centered in the pancreatic head, intractable abdominal pain, and a main pancreatic duct obstruction or stricture resulting in absent drainage into the duodenum from the uncinate process and adjacent pancreatic head areas or the entire gland. Since 1986, 57 consecutive cases with these criteria underwent PD (47 head only and 10 total pancreatectomy). Clinical and anatomic predictor variables were derived from the history, imaging studies, and pathologic examination. These variables then were tested for association with the following outcome events gathered during annual follow-up: pain relief, onset of diabetes, body weight maintenance, and peptic ulceration. RESULTS: Operative mortality was zero. In 57 patients with a mean follow-up of 42 months, the 5-year outcome event for survival was 93% and the onset of diabetes was 32%. All new cases of diabetes occurred more than 1 year after resection. In 43 cases > or =1 year postoperative with a mean follow-up of 55 months, all patients indicated significant pain relief and 76% were pain free. pain relief was more common in patients with diabetes or in those patients with a pancreatic duct disruption. Death was more common in patients with diabetes. Weight maintenance was more common if preoperatively severe ductal changes were not present. Total pancreatectomy was associated with peptic ulceration. CONCLUSIONS: Using selection criteria, the outcome analysis standardized anatomic and clinical variables as to how they were associated with the outcome events (calibrated the effects of the operation with each variable). In these selected patients, PD is safe and significantly relieves pain. Sequelae are from diabetes, provided total pancreatectomy is avoided.

Percutaneous echography-guided alcohol block of the celiac plexus as treatment of painful syndromes of the upper abdomen: study of 21 cases

Celiac plexus block is usually performed under fluoroscopic or tomodensitometric guidance. We report on a new procedure using sonographic guidance. the patient lies in supine position. We use a real-time sonograph with a 3.5 MHz probe. On a transverse plane, the celiac axis is localized emerging from the aorta. Under local anesthesia, the tip of the spinal needle (177 mm, 22 g) is placed close to the aorta (about 5 mm) on both sides. 5 to 10 ml of 1% lidocaine, then 10 to 20 ml of absolute alcohol, are injected on each side. 21 patients (10 males, 11 females, mean age: 61.4) underwent the procedure. They presented with cancer of the pancreas in 14 cases, metastatic nodes from an extra-pancreatic tumor in 5 cases and chronic calcifying pancreatitis (CCP) in 2 cases. No pain relief was secured in 3 patients (14%). One of these presented with CCP, but endoscopic cystic diversion of a small cyst was successful in eradicating pain. Partial pain relief was secured in 5 cases (24%) and total pain relief in 13 cases (62%). No treatment-related complication was observed. We conclude that sonography is a simple and safe method of guidance in performing alcohol block of the celiac plexus. The anterior approach may prevent neurologic complications occurring with other methods of guidance using a posterior approach.

Cannabis use for chronic non-cancer pain: results of a prospective survey.

There has been a surge in interest in medicinal cannabis in Canada. We conducted a questionnaire survey to determine the current prevalence of medicinal cannabis use among patients with chronic non-cancer pain, to estimate the dose size and frequency of cannabis use, and to describe the main symptoms for which relief was being sought. Over a 6-week period in mid-2001, 209 chronic non-cancer pain patients were recruited in an anonymous cross-sectional survey. Seventy-two (35%) subjects reported ever having used cannabis. Thirty-two (15%) subjects reported having used cannabis for pain relief (pain users), and 20 (10%) subjects were currently using cannabis for pain relief. Thirty-eight subjects denied using cannabis for pain relief (recreational users). Compared to never users, pain users were significantly younger (P=0.001) and were more likely to be tobacco users (P=0.0001). The largest group of patients using cannabis had pain caused by trauma and/or surgery (51%), and the site of pain was predominantly neck/upper body and myofascial (68% and 65%, respectively). The median duration of pain was similar in both pain users and recreational users (8 vs. 7 years; P=0.7). There was a wide range of amounts and frequency of cannabis use. Of the 32 subjects who used cannabis for pain, 17 (53%) used four puffs or less at each dosing interval, eight (25%) smoked a whole cannabis cigarette (joint) and four (12%) smoked more than one joint. Seven (22%) of these subjects used cannabis more than once daily, five (16%) used it daily, eight (25%) used it weekly and nine (28%) used it rarely. Pain, sleep and mood were most frequently reported as improving with cannabis use, and 'high' and dry mouth were the most commonly reported side effects. We conclude that cannabis use is prevalent among the chronic non-cancer pain population, for a wide range of symptoms, with considerable variability in the amounts used. Discussions between patients and health care providers concerning cannabis use may facilitate education and follow up, and would allow side effects and potential interactions with other medications to be monitored. Clinical trials of cannabis for chronic non-cancer pain are warranted.

Acupuncture: an evaluation in the painful crises of sickle cell anaemia.

An evaluation of acupuncture for pain relief was made in 10 patients with sickle cell anaemia during 16 pain crises. A model was developed in which the patient served as his own control and in which both patient and examiner were unaware of whether an acupuncture point or a sham site was treated. The results show (1) that pain relief was obtained in 15 of the 16 painful episodes regardless of whether an acupuncture point or a sham site was treated, demonstrating considerable overlap between the effects of needling acupuncture points and sham sites; (2) that needling at acupuncture points for pain relief is not significantly superior to treatment at sham sites; (3) that needling, per se, whether at acupuncture points of at sham sites can be useful for alleviating pain in sickle cell crises. The model could be useful for evaluation of pain relief by needling in other diseases.

Evaluation of selective lumbar radiculography and radicular block

We analyzed 56 patients who received selective lumbar radiculography and radicular block (88 procedures in total). The underlying conditions were spinal diseases in 43 cases, cancer pain in 6 cases, post-herpetic neuralgia (PHN) in 5 cases and reflex sympathetic dystrophy (RSD) in 2 cases. In the spinal disease group, 24 cases showed complete pain relief and 12 cases showed partial pain relief after the therapy, with a success rate of 83.7%. In the cancer pain group, 3 cases showed complete pain relief and one showed partial pain relief (success rate: 66.7%). In the PHN group, 1 case showed complete pain relief and 2 showed partial pain relief (success rate: 60%). In the RSD group, all cases showed pain relief. When examined 3 months after this treatment, the effect had persisted in 15 cases from the spinal disease group, in 1 case from the cancer pain group, in 2 cases from the PHN group and in 2 cases from the RSD group. Selective lumbar radiculography and radicular block are useful in identifying a nerve root responsible for abnormalities. In addition, this procedure is expected to exert a long-lasting therapeutic effect in cases indicated for the procedure.

Non-oncologic chronic pain relief with opioids

Opioids for non cancer pain control are controversial. The evaluation of the pain relief, changes in quality of life and complications due to long term infusion of opioids in the lumbar subarachnoid space in 11 patients with non cancer pain were the goals of this study. Patients were previously treated with drugs and surgical procedures, without significant pain relief. Patients were asked to compare pain characteristics and daily life activities before and after this treatment. The long term spinal opioids through implantable pumps for non-oncologic pain produced pain relief but did not improve the quality of life in the majority of the cases.

Effects and pharmacokinetics of high dose metoprolol on chest pain in patients with suspected or definite acute myocardial infarction.

OBJECTIVE: Pain intensity and the plasma concentrations of metoprolol and its major metabolite alpha-hydroxymetoprolol as well as noradrenaline (NA), adrenaline (A) and neuropeptide Y (NPY) were determined in patients with pain due to definite or suspected acute myocardial infarction (AMI) after graded metoprolol infusion. Pain intensity and metoprolol kinetics were assessed over 8 h. METHODS: Twenty-seven patients of either sex, aged 48-84 years with ongoing chest pain upon arrival to the Coronary Care Unit (CCU) were subdivided into two groups: (1) patients with ECG signs of threatening transmural myocardial damage (n = 15); and (2) patients without such ECG signs (n = 12). Pain intensity was assessed by a numerical rating scale (NRS) and venous blood was obtained for determination of plasma catecholamine and NPY concentrations. A continuous infusion of metoprolol (3 mg.min-1 i.v) was started and serial blood samples for plasma catecholamines, NPY as well as metoprolol and its major metabolite alpha-hydroxymetoprolol were obtained from the contralateral arm. RESULTS: Initial pain intensity was 5.9 (arbitrary units) and 5.4 in the groups with and without signs of transmural myocardial damage, respectively. One third of the patients with ST changes reported full pain relief (NRS = 0) within 70 min after starting metoprolol infusion (accumulated dose, 15-180 mg). Among the patients without ST changes upon arrival, full pain relief was obtained in 70% (accumulated dose, 30-120 mg). There was a dose-dependent relation between accumulated metoprolol dose and pain relief. The diagnosis of acute myocardial infarction (AMI) was confirmed in all 15 patients with ECG signs on arrival of transmural myocardial damage. The mean metoprolol dose in this group was 91(12) mg. The mean metoprolol dose in the 12 patients without ST changes was 64(8) mg. In all, seven of these patients developed definite AMI. The terminal half-life of unchanged metoprolol ranged from 2.5 to 8.5 h in group 1 and from 2.2 to 5.2 h in group 2. In group 1, metoprolol half-life was 4.5 h and total plasma clearance (CL) 54.1 1.h-1. In group 2, the metoprolol half-life was 3.7 h and total plasma clearance 75.4 1.h-1. There was a significant difference in clearance between the groups. After the intravenous metoprolol infusion, alpha-hydroxymetoprolol concentrations increased gradually. In groups 1 and 2, maximal concentrations in plasma (Cmax) were 143 and 135 nmol.1(-1) for alpha-hydroxymetoprolol and 2830 and 1653 nmol.1(-1) for metoprolol, respectively. Plasma NA or NPY did not differ between the groups. In contrast, plasma A was significantly higher during the initial 90 min of observation in patients with ECG signs of transmural myocardial damage. CONCLUSION: High-dose intravenous metoprolol was well tolerated in patients with suspected AMI. There was a more rapid and almost complete pain relief in patients without signs of transmural ischaemia compared with the patients with ECG signs of transmural AMI at arrival. In the later group of patients, plasma clearance of metoprolol was significantly reduced.