Nursing - Pain Management Essay Example | Topics and Well Written Essays - 1500 words

Nursing - Pain Management - Essay Example Cyclooxygenases Prostaglandin endoperoxide H synthase (commonly known as Cyclooxygenases) was purified in 1976 and cloned in 1988. This enzyme is the key catalytic protein in the synthesis of prostaglandins from arachidonic acid, resulting in pain and inflammation, and is subject to inhibition by non ­steroidal anti-inflammatory drugs (NSAIDS). In 1991, several laboratories identified a second gene product with COX activity, now termed COX-2. It is clear now that both isoforms, COX-l and COX-2 are expressed in both peripheral tissues and several areas of the CNS (Prochazkova et al., 2006). Theories of Pain Gatchel, Polatin, and Kinney (1995) state that there are two prominent theories of pain: the traditional specificity theory of pain and the gate control theory of pain. The former, still widely taught, proposes that pain is a specific sensation and that the intensity of pain is proportional to the extent of tissue damage. This theory implies a fixed, straight-through transmission system from somatic pain receptors to a pain center in the brain (p.416). In 1965, Melzack and Wall proposed the gate control theory. This theory suggests that there are physiological and neural mechanisms in the body that can have an effect on the perception of the painful stimulus (Hawthorn & Redmond 2001). The theory postulates that there are two controls that affect the gate. ... This gating mechanism depends on the relative quantity of information being received over the larger fibers versus the smaller fibers. In essence, the two peripheral impulses interfere with each other to alter pain perception. The gate control theory has received the most recognition in the field of pain research (Gatchel, Polatin, and Kinney 416). Anatomy & Physiology The complexities associated with the experience of pain are immense. Hall (1994) addresses those that deal with the physiological aspects by observing that medical science has not fully explained pain mechanisms. The specialization of receptors has been discovered. This refers to receptors being more sensitive to one stimulus than others. Hall (1994) continues with the identification of the receptor that is "incriminated" in the reception of pain, the unmyelinated or thinly myelinated nerve ending, an "unencapsulated" nerve ending. Hall describes the myelin sheath covering that encloses nerve fibers. The thickness of t his sheath varies throughout the body, from none in the periphery, to very thick where nerves enter bones, and other parts of the body. The covering acts as insulation to keep stimuli from entering the nerve from regions other than those served by the nerve (p. 11). Hall (1994) goes on to describe the receptor as a "primitive unorganized nerve ending and often has a weed-like appearance. It has many branches and overlaps with other receptors to totally cover the area which it serves" (p. 11). The area that a particular nerve serves is called a dermatome, which may serve an area of skin, a muscle, or any organ of the body. Hall states, "It is important to realize that the strength of stimulus is a critical factor in the production of pain in this and other