Although proper investigation of the cause and nature of the pain is essential before a management plan is set in motion, it is generally accepted that adequate analgesia lowers morbidity and improves the patient's quality of life. For instance, pain monitoring using visual analog scales like the Wong and Baker faces Pain Rating Scale for pediatric patients and the numeric rating scale for adult patients can help the medical practitioner asses the patient's pain and take appropriate action for pain control. Also, questionnaires like the McGill Pain Questionnaire allow the physician not only to assess the severity of the patient's pain but also to look at the effect of pain on the patient's quality of life. By trying to quantify and qualify the patient's pain, doctors are now able to reduce morbidity from postoperative, musculoskeletal, traumatic, and cancer pain and improve the quality of life of patients.

Painstaking

    Many minor surgical procedures like excision of small masses, circumcision, or episiotomy are performed using local infiltration of anesthetic agents such as lidocaine or bupivacaine. Postoperative pain, which kicks in after the short-acting local anesthetic has already worn off, is dealt with using convenient oral nonsteroidal antiinflammatory agents (NSAIDs). For breakthrough pain, oral opioids with or without acetaminophen may be used.

    Intermediate surgeries like a Caesarian section, appendectomy, or hysterectomy are dealt with using peripheral nerve blockade, usually via spinal anesthesia or insertion of an epidural catheter to provide continuous infusion of a local anesthetic or an opioid after the surgery.

    Traditionally, intramuscular or intravenous opioids like morphine sulfate, meperidine, and hydromorphone have been used for these procedures. The addition of parenteral or oral NSAIDs has also been shown to reduce the need for higher or more frequent doses of opioid analgesics, especially in patients already receiving opioids intrathecally.

    Major surgeries may require not only peripheral nerve blockade, but also a continuous infusion of an epidural local anesthetic or opioid, plus oral or parenteral NSAIDs and systemic opioids. Although it is an established fact that opioids can provide adequate pain relief, as high as 75 percent of hospitalized patients receiving opioids remain undertreated.

    This undertreatment may be traced to several factors like the fear of opioid addiction and respiratory depression, the failure of many hospitals to do pain monitoring, and perhaps the general acceptance that pain is a normal part of the whole surgical experience. The latter thinking may help explain in part why some patients seldom complain of pain.

    The development of patient-controlled analgesia (PCA) is empowering patients by allowing them direct involvement in managing their pain. In this system, pain relievers (usually opioids) are delivered intravenously via a pump that the patients themselves control with the push of a button.

    While the patient can have a dose on demand, the physician retains total control over how much medication the patient receives per push of the button and the intervals of administration. Modern PCA pumps are sophisticated enough to monitor how much of the analgesic agent the patient has already taken.

    Optimizing postoperative pain management depends on the surgical procedure performed, the kind and dose of pharmacologic agent used, previous exposure of the patient to analgesic agents. Analgesic control is best achieved using at least two kinds of agents that yield a synergistic effect.

Pumping Up

    The World Health Organization Analgesic Ladder initially prescribed for cancer pain management has long been used also to treat musculoskeletal, acute, and postoperative pain. This step-up algorithm has three rungs. In the first rung, NSAIDs and aspirin may be used. If pain is unrelieved adding a local anesthetic or weak opioid to the original regimen would be the next step. If both schemes still do not work, the next step would be to add or use a strong opioid.

    On the other hand, the World Federation of Societies of Anesthesiologists (WFSA) advocates a step-down approach, almost similar to the WHO version in reverse except for the use of strong opioids (via intramuscular or intravenous route) first in combination with a local anesthetic and peripherally acting drugs like NSAIDs. As the pain subsides, weaker opioids and NSAIDs may be given orally, and if the pain decreases further, then the patient may be weaned from the opioid and maintained on aspirin and NSAIDs.

    Paracetamol and aspirin, the simplest drugs on the list of pain medications, are effective in controlling mild to moderate pain. Both also have antipyretic and antiinflammatory activity. Paracetamol is cheap and may be administered orally or intravenously. It may be given at 500 to 1000mg every four to six hours as long as the daily dose does not exceed four grams. For persons with liver disease, the daily dose should not go beyond two grams.

    At oral doses of 325 to 650mg every four hours, aspirin has been shown to be effective in controlling pain and fever. Precautions on aspirin use include Reye syndrome in children and teenagers, and gastrointestinal irritation, and bleeding.

    Diclofenac, ibuprofen, mefenamic acid, naproxen, ketoprofen, ketorolac, indomethacin, piroxicam, diflunisal, etodolac, sulindac, fenoprofen, flubiprofen, meclofenamate, magnesium salicylate, and tolmetin have been used for control of pain and inflammation in many medical conditions like rheumatoid arthritis and osteoarthritis to name a few.

    Chronic NSAID users are often advised to take a proton pump inhibitor (like omeprazole 20 to 40mg or esomeprazole 40mg per day), or prostaglandin (misoprostol) to lower the risk of developing NSAID-induced gastritis. Newer COX-2 inhibitors like celecoxib, rofecoxib, and valdecoxib are safer alternatives for persons who need to take medication for chronic pain. Use of NSAIDs among the elderly should be monitored because of potential nephrotoxicity and bleeding. NSAIDs should also be given with caution to patients with renal impairment and congestive heart failure as they may exacerbate their condition.

    Opioid agonists like morphine, hydromorphone, oxycodone, methadone, fentanyl, hydrocodone, and codeine have been used alone or in combination with NSAIDs to successfully manage moderate to severe pain. Short-acting preparations have also been used and found effective for acute pain.

    Physiologic dependence, constipation, sedation, nausea, respiratory depression, and opioid allergy may occur but only at higher doses. When these happen, the opioid dose may be lowered of the patient may be shifted to another agent.

The Others

    Patient satisfaction has also been observed with the use of nonpharmacologic treatment for pain. Thermotherapy using hot or cold packs, massage, physical therapy, and rehabilitation have proved effective for musculoskeletal pain, although these necessarily do not play any role in the management of postoperative pain.

    Acupuncture, which has long been used for musculoskeletal, acute, and chronic pain, is now also being used in postoperative pain management. In fact, acupuncture has reportedly been used in lieu of local anesthetic in minor surgical procedures. One study performed at the UP-PGH in 1998 involved 11 patients that underwent extracapsular cataract extraction (ECCE). The study by Drs. Estrella Genuino and Celine Zaldivar reported that "ECCE may be safely done using acupuncture analgesia, although adjunctive analgesia with a local anesthetic still have to be used in a few patients."

    Other nonpharmacologic treatment options available are biofeedback, chiropractic, meditation, music therapy, cognitive behavioral therapy, guided imagery, cognitive distraction, and framing. Also, psychotherapy, support groups, and counseling can help deal with the psychological and behavioral aspects associated with pain and pain perception.

 

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