Pain II: new approaches to management

There is an intrinsic analgesia system in the brain with both endogenous opioid and biogenic amine links. This system provides a basis for understanding how different therapeutic approaches relieve pain. The present review critically evaluates the analgesic efficacy of the following therapies: placebo administration, transcutaneous electrical nerve stimulation, acupuncture, intrathecal and epidural opiate injection, electrical stimulation of the brain, and psychotropic drugs.     

Neck tongue syndrome: operative management.

A 53-year-old woman with assimilation of the atlas to the occiput presented with paraesthesiae in the right half of her tongue and ipsilateral neck pain aggravated by head turning. After being intermittent for several years, the symptoms eventually became persistent and increasingly incapacitating. At operation, the C2 spinal nerves were found to be compressed by protuberant atlanto-axial joints, particularly on the right side. The superficial parts of the resected C2 spinal nerves showed a loss of both myelinated and unmyelinated nerve fibres. After operation, the patient experienced partial relief of her symptoms.     

Pain management in neonates

Multiple lines of evidence suggest an increased sensitivity to pain in neonates. Repeated and prolonged pain exposure may affect the subsequent development of pain systems, as well as potentially contribute to alterations in long-term development and behavior. Despite impressive gains in the knowledge of neonatal pain mechanisms and strategies to treat neonatal pain acquired during the last 15 years, a large gap still exists between routine clinical practice and research results. Accurate assessment of pain is crucial for effective pain management in neonates. Neonatal pain management should rely on current scientific evidence more than the attitudes and beliefs of care-givers. Parents should be informed of pain relief strategies and their participation in the health care plan to alleviate pain should be encouraged. The need for systemic analgesia for both moderate and severe pain, in conjunction with behavioral/environmental approaches to pain management, is emphasized. A main sources of pain in the neonate is procedural pain which should always be prevented and treated. Nonpharmacological approaches constitute important treatment options for managing procedural pain. Nonpharmacological interventions (environmental and preventive measures, non-nutritive sucking, sweet solutions, skin-skin contact, and breastfeeding analgesia) can reduce neonatal pain indirectly by reducing the total amount of noxious stimuli to which infants are exposed, and directly, by blocking nociceptive transduction or transmission or by activation of descending inhibitory pathways or by activating attention and arousal systems that modulate pain. Opioids are the mainstay of pharmacological pain treatment but there are other useful medications and techniques that may be used for pain relief. National guidelines are necessary to improve neonatal pain management at the institutional level, individual neonatal intensive care units need to develop specific practice guidelines regarding pain treatment to ensure that all staff are familiar with the effects of the drugs being used and to guarantee access and safe administration of pain treatment to all neonates.     

Pain assessment and management

Little research is currently available related to pain management by neuroscience nurses. However, due to concerns about the potential for altering neurological status, some neurosurgery patients may not receive optimal pain management. This paper describes findings from a pain related survey which was distributed during the Canadian Association of Neuroscience Nurses June 1998 national conference. The survey was intended to assess Canadian neuroscience nurses pain management knowledge and to explore pain management techniques after intracranial surgery. While 60% of respondents answered four pain assessment and management case study related questions correctly, some respondents rated pain differently when it was expressed by a smiling or grimacing patient. The most common methods for pain control after intracranial surgery included intermittent codeine and/or morphine, often by intramuscular injection. Findings from this study suggest that some neuroscience nurses require further education about pain management and that many patients do not receive optimal pain management after intracranial surgery.     

Pain following traumatic brain injury: Assessment and management

Traumatic brain injury is frequently associated with painful complaints immediately after injury and subsequently. Early assessment of possible painful conditions can be made at the time of physical examination in those who are unable to give a history. Non-verbal signs of pain, including withdrawal of a painful limb or body part, irritability or tears should draw the attention of the assessing physician to a peripheral painful site. Treatment of conditions giving rise to pain can be made at this stage. Persistent pain may arise from a combination of physical and psychological factors and is best managed in a multidisciplinary pain clinic. Contributions from physicians in pain management, psychologists, physiotherapists and clinical nurse specialists enable a rehabilitation programme to take place. Treatments include analgesic drugs, graded exercise, cognitive-behavioural therapy, and transcutaneous electrical nerve stimulation. Rehabilitation of people who have ahead injury and pain takes longer than usual and separate pain management facilities should be developed for this population.     

Pain following traumatic brain injury: Assessment and management

Traumatic brain injury is frequently associated with painful complaints immediately after injury and subsequently. Early assessment of possible painful conditions can be made at the time of physical examination in those who are unable to give a history. Non-verbal signs of pain, including withdrawal of a painful limb or body part, irritability or tears should draw the attention of the assessing physician to a peripheral painful site. Treatment of conditions giving rise to pain can be made at this stage. Persistent pain may arise from a combination of physical and psychological factors and is best managed in a multidisciplinary pain clinic. Contributions from physicians in pain management, psychologists, physiotherapists and clinical nurse specialists enable a rehabilitation programme to take place. Treatments include analgesic drugs, graded exercise, cognitive-behavioural therapy, and transcutaneous electrical nerve stimulation. Rehabilitation of people who have ahead injury and pain takes longer than usual and separate pain management facilities should be developed for this population.     

The EAE-associated behavioral syndrome: II. Modulation by anti-inflammatory treatments

EAE is associated with sickness behavior symptoms that are temporally correlated with inflammatory processes. To further elucidate the role of inflammatory mediators in the behavioral syndrome, EAE mice were injected daily with anti-inflammatory drugs, beginning at disease onset. Dexamethasone or interleukin-1 (IL-1) receptor antagonist or the prostaglandins synthesis inhibitor indomethacin attenuated the behavioral symptoms. Administration of the tumor necrosis-factor alpha (TNF-alpha) synthesis inhibitor pentoxifylline or targeted deletion of the type I TNF receptor had no behavioral effects whereas administration of pentoxifylline in IL-1ra-treated mice further reversed the behavioral depression. These findings demonstrate the critical involvement of pro-inflammatory cytokines and prostaglandins in the EAE-associated behavioral syndrome, and may have implications for understanding and treating the neuropsychiatric disturbances in multiple sclerosis (MS) patients.     

Pain in diabetic neuropathy case study: whole patient management

Painful diabetic peripheral neuropathy (DPN) is described as a superficial burning pain associated with other positive and/or negative sensory systems affecting the feet and lower extremities. It is one of the most commonly encountered neuropathic pain syndromes in clinical practice. Presentation may be complicated by multiple symptoms, including allodynia, hyperalgesia, other less well characterized dysesthesias, and serious disruption of social functioning and mood. Peripheral nerve function may deteriorate, which can account for patient reports of diminution of pain after several years of follow-up. Although current understanding holds that the pathogenesis of DPN is multifactorial in nature, long-term studies have shown that rigorous glycemic control is the most relevant factor in clinical intervention and can delay the onset and slow the progression of neuropathy. In addition to glycemic control, other treatment approaches must be examined in order to restore quality of life for patients experiencing painful DPN. Differential diagnosis is required to isolate DPN from other unexplained chronic pain. Neurologic testing in painful DPN is an area of active research and is used to assess the neurologic pathways giving rise to the pain, the degree of neural damage and the degree of subclinical damage. Current treatment options for DPN include mainly antidepressants and anticonvulsants, with other agents such as tramadol, dextromethorphan and memantine being employed or studied. This review article includes a case study of a patient with painful DPN to demonstrate the current management strategies for this neuropathic pain syndrome.     

Schwartz-Jampel syndrome: II. Na+ channel defect causes myotonia

Skeletal muscle fibers from a patient with Schwartz-Jampel syndrome were studied in vitro. The fibers had normal resting membrane potentials, but their resting [Ca2+]i was elevated. The resting potentials were unstable and spontaneous depolarizations caused twitching in all fibers. Stimulated contractions were characterized by markedly slowed relaxation which was due to electrical after-activity. Neither curare (0.7 microM), tocainide (50 microM), nor phenytoin (80 microM) had an effect on the myotonic activity. In contrast, procainamide (200 microM) suppressed the hyperexcitability without affecting the twitch amplitude. The steady-state current-voltage relation was normal in 5 fibers, but altered in 3 others. These latter fibers had an increased specific membrane resistance owing to a decreased Cl- conductance. The Na+ channels were investigated in the cell-attached patch clamp mode. In all patches on either type of fiber, depolarizing pulses elicited delayed, synchronized openings of Na+ channels. These abnormal openings occurred even after the surface membrane repolarized. We hypothesize that these altered membrane conductances are responsible for the hyperexcitability and the associated slowed relaxation.     

Athetosis II: the syndrome of mild athetoid cerebral palsy.

We describe 8 patients who presented with continuous, irregular movements occurring independently in individual fingers and, in some cases, toes, in the setting of mild dystonia present since early childhood and not associated with major disability. The finger movements varied from low-amplitude quivering or wriggling to larger amplitude movements in the plane of abduction-adduction as well as flexion-extension; they were asymmetrical but not unilateral. Quivering or working of the facial muscles was seen in 5 patients. Most patients reported worsening of the movements over the years, but there was no other evidence of a progressive neurological disease. We classify the movement disorder as athetosis as described by Hammond and Shaw and the syndrome as mild athetoid cerebral palsy.     

Lumbar Sympathetic Chain Neuromodulation with Implanted Electrodes for Long‐Term Pain Relief in Loin Pain Haematuria Syndrome

Introduction. Loin pain‐hematuria syndrome (LPHS) is a rare clinical entity causing unilateral or bilateral intractable flank and loin pain with hematuria. The etiology is poorly understood, and the diagnosis is made by exclusion of urological and nephrological conditions. The management is mainly symptomatic aiming for pain relief with nonopioid and opioids analgesics, and interventions such as capsaicin infusion into the renal pelvis, percutaneous regional nerve blocks, and laparoscopic or open surgical procedures, none of them providing lasting pain relief. Methods. We describe four cases of LPHS in which long‐term pain relief was achieved successfully by neuromodulation of lumbar sympathetic plexus with implanted electrodes. All patients underwent an initial successful trial of neuromodulation with Stimulong monoelectrode (Pajunk, GmbH, Geisingen, Germany) inserted percutaneously to lie adjacent to L3–L4 vertebral bodies followed by permanent implantation of the stimulation system using four contact electrodes (Medtronic Inc, Minneapolis, Minnesota, USA) in two patients with excellent long‐term pain relief. Results. All our patients had significant reductions in visual analog scale scores and analgesic consumption for the duration of the monoelectrode trial and in one patient beyond six months. Of the two patients who had full implants, pain relief is excellent with minimal analgesic consumption and one has resumed employment. There were no complications. Discussion. LPHS is very difficult to treat with some experts maintaining it is mainly psychological. Conservative treatments are often unsatisfactory and radical measures not reliable. Peripheral stimulation of nerves and plexuses has been successful as shown from case reports. All our patients preferred low‐frequency stimulation although its precise mode of action is uncertain. Conclusion. Our experience shows that lumbar sympathetic chain neuromodulation in intractable LPHS not amenable to conservative therapy is a reasonable alternative before radical interventions. More experience is needed in multiple centers before its recommendation for refractory LPHS.     

Psychological aspects of premenstrual syndrome. II: Utility of standardized measures.

Depressed mood is a salient feature of Premenstrual Syndrome (PMS). Fourteen women with prospectively documented PMS and ten without PMS completed the short form of the Beck Depression Inventory (BDI) and the Zung Self-Rating Scale for Depression (Zung-D) during the follicular and late luteal phases of two consecutive menstrual cycles. The short form of the BDI assesses the more cognitive symptoms of depression, while the Zung-D identifies primarily vegetative symptoms. The short form of the BDI was sensitive to cyclic changes in the PMS women, while the Zung-D was not. The BDI items uniquely endorsed by the PMS women during the late luteal phase were pessimism, sense of failure, dissatisfaction, guilt, self-dislike, and indecision. The premenstrual dysphoria experienced by PMS women thus appears to be more cognitive than vegetative in nature. Finally, differential utility of standardized mood measures to detect premenstrual depression is suggested. The BDI proved to be the more sensitive measure.