Acute pain is common in the hospital from disease processes and surgery. According to "Miller's Anesthesia," pain is classified into nociceptive, in which the nerve endings sense pain signals, and neuropathic, in which damaged nerves signal pain to the brain. Pain specialists -- typically anesthesiologists -- use a number of different techniques to relieve pain.
Oral and Intravenous Pain Medications
The World Health Organization uses a three-step "analgesic ladder" to describe the delivery of increasingly stronger pain medications. Step 1 is for mild pain, and involves the administration of non-opioid analgesics, including NSAIDs, or nonsteroidal anti-infalmmatory medications such as ibuprofen and ketorolac, the latter being one of the most powerful NSAIDs, according to "Raj's Practical Management of Pain." Step 2 is for moderate pain, and suggests using step 1 drugs plus a mild opioid. Opioids are drugs -- such as morphine -- derived from the poppy plant. Step 3 involves the use of step 1 drugs plus powerful opioids. These drugs can be delivered in many ways, such as a pill by mouth, under the tongue, a patch on the skin or into the veins through an IV catheter.
Spinal Analgesia
Spinal analgesia numbs the nerves of the spinal column. In addition to dulling the sensation of pain, spinal analgesia can affect other nerves as well. Injections of local anesthetics can be made into the spinal fluid. This is possible because while the back bone extends from the head to the hips, the spinal cord does not extend all the way down the back bone. Injections are made below the level of the spinal cord. An epidural is a flexible catheter that is threaded into a space near the spinal nerves to continuously deliver numbing medications to the nerves.
Nerve Blocks
Nerve blocks are more selective of the area numbed than spinal anesthesia. For example, part or all of the left arm could be numbed if this is where the pain is originating. The location of the nerves can be determined using anatomic landmarks or an ultrasound machine. A small needle is used to deliver long-acting numbing medication to the affected area.
References
- "Miller's Anesthesia"; Ronald D. Miller, M.D.; 2009
- "Raj's Practical Management of Pain"; Honorio Benzon, M.D.; 2008
