UI - 000122

AU - Fogel BS

AU - Fretwell MD

TI - Common mental health problems in geriatric practice. Part II: Insomnia, chronic pain, troubled

families, and other dilemmas

SO - Rhode Island Medical Journal 1991;74:68-7

UI - 000112

AU - Foldes FF

TI - Pain control with intrathecally and peridurally administered opioids and other drugs. [Review]

AB - Sharp pain is conducted rapidly by myelinated delta A fibers and diffused pain slowly by

nonmyelinated C fibers to pseudobipolar neurons in the posterior ganglion and

from there to neurons located in the posterolateral horn of the spinal cord. From here on nociferous impulses

are transmitted by excitatory peptides (e.g. substance P) or amino acids (e.g. glutamate, aspartate) through

interconnecting neurons of the pain pathways, primarily on the contralateral side, to the brain stem and from

there to the sensory cortex, where they are appreciated and acted upon. There are specific inhibitory

receptors located on axon terminals, near to the release sites of the excitatory amino acids and peptides.

Stimulation of these receptors by their appropriate ligands such as endogenous (e.g. enkephalis, endorphins)

or exogenous opioids, clonidine, serotonin, somatostatin inhibits the release of excitatory neurotransmitters

and relieves pain. There are at least 3 different opioid receptors, called mu-, kappa- and delta-receptors in

the spinal cord. These can be differentiated from one another by their specific affinity toward different

endogenous or exogenous opioids and the pure narcotic antagonist, naloxone. It appears that the nociferous

impulses transmitted by parallel pathways equipped with different inhibitory receptors have to be integrated

to produce pain sensation and partial inhibition of transmission in different pathways or complete inhibition

in one of the pathways may relieve pain. In recent years the concept of "selective spinal analgesia" has been

applied clinically for the relief of postoperative, obstetrical and chronic pain. At first it was expected that the

intrathecal or peridural administration of morphine will produce analgesia without the side effects of

systemically administered morphine. It soon became evident, however, that intrathecally and peridurally

administered morphine after several hours of delay reaches the fourth ventricle and by stimulating mu-

receptors may cause respiratory depression and other undesired effects (e.g. nausea, vomiting, pruritus).

Several different approaches are being investigated for the production of selective spinal analgesia without

side effects. They include: a. the use of more lipophilic, long-lasting opioids (e.g. lofentanil) which would be

almost completely absorbed by the spinal cord and therefore would not reach the medullary centers; b. the

development of opioids with specific affinity to kappa- and for delta- and little or no affinity to mu-

receptors, primarily responsible for side effects; and c. combining lower doses of opioid agonists with alpha

2-adrenergic agonists (e.g. clonidine) or with somatostatin. It is conceivable that in the not-too-distant

future, it will be possible to achieve through these measures, selective spinal analgesia without side effects.

[References: 68]

SO - Anaesthesiologie und Reanimation 1991;16:287-29

UI - 000118

AU - Forman WB

AU - Stratton M

TI - Current approaches to chronic pain in older patients. [Review]

AB - As the population ages, primary care physicians face an increasing number of individuals who suffer

from the effects of chronic diseases, including the accompanying chronic pain. This article reviews the

common causes of pain in the elderly and suggests a system for assessing its severity. Five different

approaches to treating pain in this population are outlined, as are guidelines for managing the potential side

effects of treatment. [References: 20]

SO - Geriatrics 1991;46:47-5