| Background | The majority of human orthopedic trauma patients are treated with opioids which are frequently associated with negative side effects, including the propensity to become persistent opioid users. |
| Rational and Objective | Multimodal analgesia tailored to individual patients may provide more effective pain management, lower opioid dependence, and result in fewer side effects than opioids alone. |
| Trial Design | Literature review |
| Patient population and location | Human, generalized on age (mostly adult) Separated into isolated injury and polytrauma injury |
| Methods | Literature review of orthopedic pain management methods: Analgesic methods reviewed were topicals (lidocaine, NSAIDS, cryotherapy, transcutaneous electrical nerve stimulation – TENS), oral systemics (acetaminophen, selective NSAIDS/non- selective NSAIDS/COX-2 inhibitors, gabapentoids, muscle relaxants), intravenous systemics (lidocaine, ketamine, alpha-2 agonists, neuraxial, local anesthetics, peripheral nerve blocks, fascial plane blocks ). |
| Endpoints (if applicable) | Not applicable |
| Results | Topicals:NSAIDS provide >50% pain relief in simple trauma (strains/sprains)Lidocaine was effective in neuralgias, no evidence in post-traumatic/postsurgical painCryotherapy and TENS provided limited analgesia in traumaOral Systemics:Acetaminophen does not reduce reported pain and is likely best given as a scheduled medication versus as needed.NSAIDS provide the single most effective analgesic in acute pain; combined with acetaminophen can provide better pain relief than either single agent.Selective COX-2 inhibitor celecoxib provides similar analgesia as non-selective NSAIDS without effecting platelet function.Gabapentoids did not decrease pain scores, but modestly decreased opioid use. Seemed more effective with pronociceptive surgeries.“Muscle relaxants” like methocarbamol provided little relief in acute pain other than lower back pain.Intravenous medicationsLidocaine constant rate infusion is a mild analgesic that is safe and had no significant adverse events in a meta-analysis of 50 trails. Lidocaine is as effective as single dose morphine after acute limb trauma and has multiple positive effects (reduced nausea, decreased hospitalization stay, reduced opioid consumption, reduced intestinal effects).Ketamine is a potent analgesic with clear opioid sparing effects and can reduce short-term and long-term opioid consumption. Ketamine is well tolerated, with some occasional adverse effects including nausea, vomiting and vivid dreams.Alpha-2 agonist dexmedetomidine is an effective opioid sparing analgesic that reduces pain, nausea and opioid doses. Bradycardia and hypotension are common side-effects.Neuraxial and peripheral nerve blocks have the best evidence in a single analgesic with a decrease in pain scores. Fascial plane nerve blocks are preferred over epidural in complex trauma patients due to higher safety margin and improved side effect profiles. Single and continuous nerve blocks both provide excellent analgesia (sometimes better than systemic medications) and can help avoid general anesthesia. |
| Limitations | Comparison of techniques from various studies must be done with caution in literature reviews. |
| Clinical Relevance Conclusions | Multi-modal analgesic practices (versus opioid analgesia) will often improve effectiveness of pain management, tailor pain management to individual needs, reduce recovery side effects, be cost effective, and avoid opioid addiction potential. [Opioid addiction is not usually an issue in veterinary patients.]The superiority of opioids is unclear when compared to other analgesics as single-dose pain relief for extremity trauma.Algorithms for pain management give a starting guide for first line analgesia and second line analgesia based on severity of injury and desired level of analgesia. A multimodal approach and balance with opioids using this algorithm will most likely improve the desired outcome.With simple isolated limb injury, the preferred approach is to maximize first-line analgesics (local anesthetics, topicals, acetaminophen, NSAIDS). [Acetaminophen has some limitations in veterinary medicine.]Complex, multi-system injuries require a comprehensive approach with second-line analgesics (gabapentinoids, intravenous infusions, “muscle relaxants”, neuraxial ). |
