Page 381 Guide to Pain Management in Low-Resource Settings

Appendix: Glossary 369

worldwide. Th e expansion of physician-assisted suicide level, avoidance of thought and feeling dominates, along
is expected to be harmful and to be in competition with with (partial) amnesia, limited emotional scope, reduc-
the development of palliative care. Experiences in the tion in interest levels, and alienation. Physiological reac-
countries practicing physician-assisted suicide suggest tions are diffi culties in falling asleep or disturbed sleep,
that too many patients not meeting the original require- increased irritability, inability to concentrate, hypervigi-
ments for this “last resort” are included. Apart from lance, and exaggerated shock reactions. Chronic pain
legal discussions, physician-assisted suicide has to be may also occur after the trauma in connection with in-
balanced against the Hippocratic oath of the physicians juries or even later, particularly in the case of headaches.
and religious teachings.
Psychiatric comorbidity
Placebo
With regard to the prevalence of psychiatric disorders
A “sugar pill” or any dummy medication or treatment such as anxiety, depression, and somatoform disorders
that causes the placebo response. A remarkable phe- in chronic pain patients, there are great diff erences in
nomenon in which a placebo—a fake treatment—can the results of clinical tests. Statements of prevalence
sometimes improve a patient’s condition simply because vary from 18% to 56%; furthermore, the details are de-
the person has the expectation that it will be helpful. pendent on the treatment parameters. Th e prevalence
Expectation plays a potent role in the placebo eff ect. of chronic pain and comorbidity with the depression-
Also, preconditioning eff ects generate a placebo re- anxiety spectrum are nearly consistent across devel-
sponse. Th erefore, testing the “adequate reaction” by a oped and developing countries. Th e age-standardized
placebo will not be able to prove “inadequate analgesic prevalence of chronic pain conditions in the previous 12
demand.” Th e reason is that expectations and precon- months was 37% in developed countries and 41% in de-
ditioning are potent principles that are able to mimic veloping countries, and overall the prevalence of pain is
the analgesic response. To be able to truly test an “ad- greater among females and older persons, but the large
equate reaction” of a patient to an analgesia procedure, majority do not meet the criteria for depression or anxi-
short- and long-acting substances should be tested sub- ety disorder.
sequently. An “inadequate response” would be if the pa-
Public health
tient responds identically to both substances (e.g., short-
acting lidocaine and long-acting bupivacaine in a nerve Th e approach to medicine that is concerned with the
block). health of the community as a whole. Public health is
community health. It has been said that: “Health care is
Postherpetic neuralgia (PHN)
vital to all of us some of the time, but public health is
Neuropathic pain in the aff ected dermatome following vital to all of us all of the time.”
a varicella infection with herpes zoster (“shingles”), usu-
Quackery
ally defi ned as pain longer than 6–12 weeks after the
onset of herpes zoster. Allodynia is often present and Deliberate misrepresentation of the ability of a sub-
diffi cult to treat. stance or device for the prevention or treatment of dis-
ease. We may think that the day of patent medicines is
Post-traumatic stress disorder (PTSD)
gone, but look around you and you will still see them.
Th e reasons for developing PTSD can be manifold. In Th ey appeal to our desire to believe that every disease
the fi eld of research, a number of categories have been is curable or at least treatable. Quackery also applies to
examined—criminal victimization, partner abuse, sex- persons who pretend to be able to diagnose or heal peo-
ual victimization, childhood abuse, political trauma, ple but are unqualifi ed and incompetent.
disasters, or a threat to one’s life. Th e prevalence of
PTSD in pain patients varies from 0.5% to 9%, in com- Receptor
parison to persons without pain, where it ranges from In cell biology, a structure on the surface of a cell (or in-
nearly 0.5% to 3%. An extreme experience of pain dur- side a cell) that selectively receives and binds a specifi c
ing the trauma increases the likelihood of developing substance. Th ere are many receptors; for example, the
the symptoms of PTSD. Th e symptoms of a PTSD are receptor for substance P, a molecule that acts as a mes-
intrusions (involuntary and stressing memories), night- senger for the sensation of pain, is a unique harbor on
mares, and fl ashbacks. On the cognitive and emotional the cell surface where substance P docks.