Page 54 - herina surgery and possible lawsuits

be 3 months. The IASP allow considerations of further characteristics in relation to

the "appropriateness" of the disorder.
• The two most commonly used chronological markers to denote chrome para have
been three and six months since the initiation of pain, however these distinctions are

arbitrary. [12]
• In acute pain there is an advantage to the individual, as it allows rest and the

inflammatory process of healing to occur. In chronic pam there is no biological value,
as there is no advantage to the individual in experiencing persistent pam.

• The Practice Guidelines of the American Society of Anaesthesiologists for Chrome
Pain Management considered chrome pain as a "persistent or episodic pam of a

duration or intensity that adversely affects the function or well being of the patient,
attributable to any non-malignant etiology"[105].
Characterization of Chronic pain:

Portenoy categorized both acute and chronic pain as nociceptive, neuropathic or psychogenic
in origin. [106]

Nociceptive pam. is due to chronic activation of nociceptive afferent neurons and it may
be somatic or visceral. In nociceptive pain due to tissue inflammation, the sensory
experience reflects the normal adaptive functioning of the pam system.[107]

Neuropathic pam. is caused by a primary lesion or dysfunction m the nervous system. It
is due to central reorganization of sensory processing after injury to an afferent

pathway. It may be sustained by-

(1) mechanisms that involve disturbances in the peripheral nerve or nerve
root- peripheral neuropathic pain, or

(2) the reorganization of nociceptive information processing by the central
nervous system- deafferentation syndrome.[ 12]

• The pathway for pam and temperature is known as the spinothalamic pathway and

their ‘Gate Control theory of pam’ emphasized the central nervous system as an active
system that filters, selects and modulates the inputs of the peripheral nervous system.
It also emphasized the dorsal horns as dynamic activity stations where inhibition,

excitation and modulation can occur. [108]

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