Acute Pain
Acute pain is the symptom of a larger disease process, and is usually nocioceptive in nature. This means that a noxious (unpleasant) event stimulates the intact nervous system to produce the sensation of pain. Examples of this noxious event include a surgical incision, labor pain, acute pancreatitis or a myocardial infarction.
Acute pain can be somatic or visceral or neuropathic in origin. Somatic pain is sharp and well localized in nature, usually to an external site. Visceral pain tends to be dull and vaguely localized to a deep site, and is frequently associated with nausea. Acute pain is self-limiting, and resolves when the noxious stimulus ceases.
Physiological and psychological responses to acute pain are directed toward escape from the painful situation. Acute pain usually triggers a neuroendocrine stress response, which is proportional to the intensity of the pain. This is a variant of the fight-or-flight response. Catecholamines are released, increasing heart rate, blood pressure, and systemic vascular resistance. Other effects of this catecholamine release may include urinary retention, ileus, stress ulcers, increased work of breathing, nausea, and constipation.
The predominant emotional response to acute pain is anxiety, although anger toward caretakers may also be expressed. These emotional responses indicate that the patient believes the pain to be temporary and “fixable”, and represent an attempt to escape from the painful stimulus.
Acute pain usually responds well to non-steroidal pain relievers and/or narcotics. Frequently, neural blockade can effectively relieve acute pain and de-
crease the likelihood of developing a chronic pain syndrome.
Antipyretic medications include acetaminophen (Tylenol, Tempra and others), NSAIDs such as ibuprofen (Advil, Motrin and others) and aspirin. They all act by interrupting chemical messengers which act to raise your child’s temperature “set point”. Aspirin is no longer recommended for children and adolescents because of the association with aspirin use and viral infections (influenza and chicken pox) leading to Reye+Syndrome, a syndrome of acute liver and brain inflammation.
Proper dosing of fever medication is very important–if under-dosed it will not be effective, and if overdosed it can be toxic. You should always check the concentration of the medication you are using. For example, Infants’ Tylenol Concentrated Drops is 80 mg per 0.8 ml, whereas Children’s Tylenol Elixir is 80 mg per ¬Ω teaspoon or 2.5 ml. Under the age of 6 months you should contact your physician regarding fever medication for your child. Guidelines for children over the age of 6 months are as follows: (see “Medicine Cabinet” for calculating a dose based on your child’s exact weight)
acetaminophen dosing
10-15 milligrams (mg) per kilogram (kg) body weight every 4 to 6 hours as needed
ibuprofen dosing
10 mg per kg every 6 to 8 hours
Treating a fever does not treat the underlying infection. Nor does response to fever therapy indicate that the infection is less severe. However, it is important to treat fevers to ease your child’s discomfort, as well as to lower your child’s metabolic rate ( important when asthma and respiratory problems are a concern).