Pain
-
Chronic pain and depression often coexist, but there is still uncertainty about the nature of this relationship. Virtually all the available data are cross-sectional and therefore do not clarify the causal relationship between the two variables. In epidemiological studies, chronic pain has often been defined fairly liberally in terms of the actual duration. ⋯ Those with data on both occasions represent 76% of an initial population of 3059 persons. On logistic regression analysis depressive symptoms at year 1 significantly predicted the development of chronic musculo-skeletal pain at year 8 with an odds ratio of 2.14 for the depressed subjects compared with the non-depressed subjects. In patients in whom pain was present at baseline no socio-demographic variable alone predicted its persistence; however, male sex and white race together with 2 items of the CES-D did predict the persistence of existing pain.(ABSTRACT TRUNCATED AT 250 WORDS)
-
Two psychological processes mediating the influence of anxiety on pain have been proposed: an attributional process in which the pain-relevance of anxiety is the essential factor, and an attentional process in which the focus of attention is the essential factor. The present study investigated the influences of attentional focus, pain-irrelevant anxiety and pain-relevant anxiety in a within-subject design (n = 40). Subjects received painful electrical stimulation in each of 5 experimental conditions. ⋯ The attributional theory seems to hold for autonomic pain responses. However, these responses might as well be considered as fear responses. Whereas there is clear evidence for a role of attentional focus in the influence of anxiety on pain, the role of attributional processes remains to be demonstrated.
-
Randomized Controlled Trial Comparative Study Clinical Trial
Low-dose intra-articular morphine analgesia in day case knee arthroscopy: a randomized double-blinded prospective study.
The aim of this study was to demonstrate the effect of intra-articular morphine following knee arthroscopy performed in infiltration analgesia. Fifty-two healthy patients were randomized to receive either 1 mg of morphine or placebo. The pain was assessed 2, 4, 8 and 24 h after the procedure by (1) a VAS scale and (2) the amount of acetaminophen consumed. ⋯ Stratifying data in therapeutic versus diagnostic arthroscopy indicated additional effect of morphine in patients undergoing therapy (P < 0.1), an aspect supporting the hypothesis of peripherally administered morphine as a potential suppressor of the substance P-mediated cytokine cascade and the peripheral leukocyte activity. Intra-articular morphine (1 mg) after knee arthroscopy offers efficient analgesia lasting more than 24 h. The method is devoid of side effects and deserves wider recognition.
-
Comparative Study
A comparison of pain measurement characteristics of mechanical visual analogue and simple numerical rating scales.
Numerical rating scales and mechanical visual analogue scales (M-VAS) were compared for their capacity to provide ratio scale measures of experimental pain. Separate estimates of experimental pain sensation intensity and pain unpleasantness were obtained by each method, as were estimates of clinical pain. Orofacial pain patients made numerical scale and VAS ratings in response to noxious thermal stimuli (45-51 degrees C) applied for 5 sec to the forearm by a contact thermode. ⋯ Both M-VAS and numerical rating scales produced reliably different stimulus response functions for pain sensation intensity as compared to pain unpleasantness and both provided consistent measures of experimental and clinical pain intensity. Finally, both mechanical and pencil-and-paper VAS produced very similar stimulus-response functions. The ratio scale properties of M-VAS combined with its ease of administration and scoring in clinical settings offer the possibility of a simple yet powerful pain measurement technology in both research and health care settings.
-
Idiosyncrasies of trigeminal neuralgia provide both clues and constraints on candidate hypotheses concerning the underlying neural mechanism. After reviewing the key clinical aspects of the disease, we propose here a novel hypothesis based on recent findings from experimental nerve-injury preparations. The hypothesis states that trigger stimuli set off bursts of activity in a small cluster of trigeminal ganglion (TRG) neurons that have been rendered hyperexcitable as a result of TRG or trigeminal root damage. ⋯ After a brief period of autonomous firing (seconds to minutes), activity is quenched and a refractory period is initiated by an intrinsic suppressive (hyperpolarizing) process engaged as a result of the rapid firing. The primary abnormality resides in the TRG and trigeminal root, rather than in the skin or the CNS. Because of this, sensation is essentially normal between periods of ectopic paroxysmal TRG discharge.