Jawahar N. Ghia

Acupuncture and chronic pain mechanisms.

&NA; Forty patients with chronic pain below the waist level not amenable to conventional medical and/or surgical treatment were randomly assigned to one of two different methods of acupuncture, after studying the underlying pain mechanisms using a Multidisciplinary Pain Clinic approach and the differential spinal block (DSB). One group received acupuncture needling in the classical acupuncture points referred to as meridian loci needling (MLN) and the other group received tender area needling (TAN) with needles inserted in the dermatomal distribution of the painful areas. The responses between the two groups showed no significant difference. Results were then related to the predetermined somatopsychological basis of the individuals pain problems as classified by the DSB. A group of patients in whom pain relief occurred upon subarachnoid injection of 0.25% procaine followed by sympathetic blockade or 0.5% procaine injection followed by hypalgesia without motor loss, also reported maximum subjective improvement in their pain level following acupuncture therapy performed at a later time. The other group of patients in whom pain persisted despite sensory and motor blockade (1% procaine) responded very poorly to acupuncture therapy. DSB was found to be complimentary to acupuncture therapy in that it facilitated patient selection for the therapy.

Effects of intravenous tetrahydrocannabinol on experimental and surgical pain; Psychological correlates of the analgesic response

Two intravenous doses of tetrahydrocannabinol (THC) (0.022 mg/kg and 0.044 mg/kg) were compared to intravenous diazepam (0.157 mg/kg) and to placebo (Ringers lactate) as premedication for dental extraction in 10 healthy volunteers. Pain detection and tolerance thresholds were measured and psychiatric interviews were supplemented by Minnesota Multiphasic Personality Inventories (MMPI), the Zung Depression Scale (ZDS), Beck Depression Inventories (BDI), and the State‐Trait Anxiety Inventory (STAI). Pain detection thresholds were altered unpredictably with high THC doses, but analgesia as indicated by pain tolerance was less than that after diazepam and placebo. In three subjects low‐dose THC (0.022 mg/kg) was a better analgesic than placebo but not diazepam. Six subjects preferred placebo to low‐dose THC as an analgesic; this group experienced increases in subjective surgical pain and were submissive, rigid, and less introspective with high State Anxiety and MMPI profiles that differed from subjects whose pain was not increased. STAI following THC presaged a poor analgesic response in this group.

Biphasic Depression of Ventilatory Responses to CO2 Following Epidural Morphine

The authors examined the duration of effects of lumbar epidural morphine (0.1 mg/kg) on control of ventilation (CO2 response), pain relief, segmental analgesia (loss of pain in response to a painful stimulus) and loss of temperature discrimination, and plasma morphine concentrations in seven patient

A retrospective study of the incidence and causes of failed spinal anesthetics in a university hospital.

One hundred sequential spinal anesthetic procedures were reviewed retrospectively to study specifically the incidence and causes of spinal anesthesia. Variables examined included the patient population, the technical aspects of performing subarachnoid tap and subsequent blockade, and the level of training of the anesthetists. We found a 17% incidence of spinal failure, defined as the need to use general anesthesia during the surgical procedure. Failure was found to be significantly associated with a lack of free flow of cerebral spinal fluid, the use of tetracaine without epinephrine, and an increased administration of intravenous supplementation. Forty-one% of the failures represented errors in judgement, either in not properly anticipating the duration of surgery or injecting local anesthetic solution in the absence of a free flow of cerebral spinal fluid. An incidental finding was the lack of documentation in many of the variables examined. We attribute the high incidence of failed spinal anesthesia mainly to technical reasons, most of them avioidable. The use of local and regional anesthesia requires considerable technical skills and demands a precise and total understanding of regional anatomic relationships. With the decreasing use of regional anesthesia in our operating room, only those regional anesthesia techniques that require minimum dexterity, such as Spinal and epidural anesthesia, continue to be utilized widely; and even these techniques, safe as they are, are being poorly taught.

Transcutaneous electrical nerve stimulation: an alternative approach to the management of postoperative pain.

HE MANAGEMENT of postoperative pain has T been and continues to be a significant problem in surgical practice in terms of both the additional stress it places on the patient’s physiologic reserves and the symptomatic discomfort it causes. It is well known by practitioners that pain is an individual experience and this fact is reflected in a wide variation in the incidence and severity of pain and in the need for analgesics. A number of factors including age, anesthetic technique, personality of the patient, previous experience, physical status, site of operation, and surgical management affect the incidence of postoperative pain (1, 2). In light of the problems associated with postoperative pain, various strategies for the management of pain have been proposed. The most commonly used method stresses the use of systemic analgesics, narcotics, and related drugs. Regional analgesia offers an attractive alternative to the use of narcotics and tranquilizers in that respiratory depression and sedation are avoided and the patient can be made pain free for extended periods using long-acting local anesthetics.

High versus low intensity acupuncture analgesia for treatment of chronic pain: Effects on platelet serotonin

&NA; The 26 chronic pain patients were tested in a baseline plus cross‐over design. Half of the subjects were first treated with high intensity acupuncture; then they were treated with low intensity acupuncture. For the other 13 subjects the treatment order was reversed. In the first treatment sequence subjects reported lower pain estimates and engaging in more activities of daily living during treatment with high intensity acupuncture — but not with low intensity acupuncture. In addition, under high intensity acupuncture (i.e. with low pain levels), subjects had higher levels of platelet serotonin; this last finding is consistent with recent research which implicates central serotonin in pain control. The results of the second treatment sequence were ambiguous.

Acupuncture and chronic pain mechanisms: The moderating effects of affect, personality, and stress on response to treatment

&NA; The present study, part of a larger project investigating neurophysiological and psychosocial factors affecting response to acupuncture for chronic pain, compares responders and non‐responders to acupuncture on a series of variables assessing personality, affect and stress. Subjects were 40 patients with pain beneath the waist level longer than 6 months duration selected from the roles of the Multidisciplinary Pain Clinic. Responders, defined as 50% or more reduction in pain estimate for greater than two weeks, were found to be less depressed, less passive and overly conventional, have shorter duration of pain, endorse less frequent exposure to stressors, and have less serious non pain‐related illnesses. The findings are viewed as linking the intractability of pain states with psychosocial factors which may directly interfere with response to somatic modes of therapy or which may interfere via alterations of tonic neurohumoral factors. The study also is seen as supporting the importance of considering psychological variables in evaluating patients for pain treatment strategies and suggests inclusion of such variables in investigating response to other modalities of treatment for chronic pain.

Serotonergic Activity in Man as a Function of Pain, Pain Mechanisms, and Depression

Lumbar cerebrospinal fluid levels of 5-hydroxyindoleacetic acid, which are used as indicators of central nervous system serotonergic neuronal activity, were significantly higher in 67 patients with chronic pain and in 32 patients with acute pain (23.6 ± 3.3 and 23.1 ± 3.8, respectively) than in 30 patients (8.8 ± 1.7) who had no pain. However, there was no correlation between levels of 5-hydroxyindoleacetic acid in patients with chronic or acute pain, nor between groups of patients with chronic pain whose pain mechanisms were of psychogenic, sympathetic, somatic, or central origin, based on their responses to differential spinal block; there was also no correlation between levels of depression, as evaluated by the Zung scale, in patients with different types of chronic pain, even though ail of these patients were depressed. The elevated levels of 5-hydroxyindoleacetic acid in the depressed patients with chronic pain are not consistent with previous studies on the etiology and types of chronic pain. As recent research indicates that the perception of pain may be modulated by endogenous analgesic systems involving enkephalin and serotonin (5-HT), this study was undertaken to clarify the association between 5-HT activity and nociception. Our findings did show a link between acute noxious stimulation and central increases in serotonergic activity. However, we could not differentiate between pain mechanisms and degree of depression. Our studies did indicate that, because of both the persistence of pain complaints and the increased levels of brain 5-HT activity, the endogenous analgesic systems are not totally effective as natural inhibitors of pain. Furthermore, the increased depression and continued pain in the presence of elevated 5-HT activity in patients with chronic pain may represent a tolerance or decreased responsiveness to 5-HT.

The pain profile: a computerized system for assessment of chronic pain

&NA; A computer‐based system to assess and quantify three components of the chronic pain experience is described. The system produces a Pain Profile and classification for each patient based on a mathematical comparison of the pathophysiologic, psychological and behavioral aspects of chronic pain. This computer‐based evaluation assists the researcher in analyzing the relative importance of the chronic pain components and helps direct the clinician to the appropriate emphasis of therapy.

Caudal anesthesia in a patient with ankylosing spondylitis for hip surgery.

Rheumatic joint diseases account for a significant proportion of orthopedic procedures, and their multisystem manifestations challenge the anesthetists imagination and proficiency. Particularly troublesome are those patients with ankylosing spondylitis (Marie-Strumpell arthritis) in whom cervical f